AMARIN CORP PLC\UK - Quarter Report: 2015 September (Form 10-Q)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

For the quarterly period ended September 30, 2015

OR

For the transition period from                      to                     

Commission File No. 000-21392

Amarin Corporation plc

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: +353 (0) 1 6699 020

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    YES  x    NO  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§229.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    YES  x    NO  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    YES  ¨    NO  x

182,530,173 shares held as American Depository Shares (ADSs), each representing one Ordinary Share, 50 pence par value per share, and 956,654 ordinary shares, were outstanding as of November 1, 2015.

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INDEX TO FORM 10-Q

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PART I

AMARIN CORPORATION PLC

CONDENSED CONSOLIDATED BALANCE SHEETS

(Unaudited, in thousands, except share amounts)

See notes to condensed consolidated financial statements.

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AMARIN CORPORATION PLC

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited, in thousands, except per share amounts)

See notes to condensed consolidated financial statements.

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AMARIN CORPORATION PLC

CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS’ DEFICIT

(Unaudited, in thousands, except share amounts)

See notes to condensed consolidated financial statements.

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AMARIN CORPORATION PLC

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited, in thousands)

See notes to condensed consolidated financial statements.

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AMARIN CORPORATION PLC

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

For purposes of this Quarterly Report on Form 10-Q, our ordinary shares may also be referred to as “common shares” or “common stock.”

Nature of Business

Amarin Corporation plc (“Amarin” or the “Company”) is a biopharmaceutical company with expertise in lipid science focused on the commercialization and development of therapeutics to improve cardiovascular health.

The Company’s lead product, Vascepa^® (icosapent ethyl) capsules, is approved by the U.S. Food and Drug Administration, or FDA, for use as an adjunct to diet to reduce triglyceride levels in adult patients with severe (TG ³500 mg/dL) hypertriglyceridemia. Vascepa is available in the United States by prescription only. The Company began selling and marketing Vascepa in the United States in January 2013. The Company sells Vascepa principally to a limited number of major wholesalers, as well as selected regional wholesalers and specialty pharmacy providers, or collectively, its Distributors, that in turn resell Vascepa to retail pharmacies for subsequent resale to patients and health care providers. The Company markets Vascepa through its sales force of approximately 150 sales professionals, including sales representatives and their managers. In May 2014, Kowa Pharmaceuticals America, Inc. commenced co-promotion of Vascepa in accordance with a co-promotion agreement with the Company. Kowa Pharmaceuticals America, Inc. co-promotes Vascepa through its approximately 250 sales representatives who now devote a substantial portion of their time to promoting Vascepa in conjunction with the promotion of Kowa Pharmaceutical America, Inc.’s primary product, a branded statin for patients with high cholesterol. The Company operates in one business segment.

The Company is also developing Vascepa for FDA approval of potential additional indications for use. In particular, the Company is conducting a cardiovascular outcomes study of Vascepa, titled REDUCE-IT (Reduction of Cardiovascular Events with EPA—Intervention Trial). The REDUCE-IT study is designed to evaluate the efficacy of Vascepa in reducing major cardiovascular events in a high-risk patient population on statin therapy.

Basis of Presentation

The condensed consolidated financial statements included herein have been prepared by the Company, without audit, in accordance with accounting principles generally accepted in the United States of America (the “U.S.” or the “United States”) and pursuant to the rules and regulations of the Securities and Exchange Commission, or the SEC. Certain information in the footnote disclosures of the financial statements has been condensed or omitted where it substantially duplicates information provided in the Company’s latest audited consolidated financial statements, in accordance with the rules and regulations of the SEC. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and notes included in its Annual Report on Form 10-K for the fiscal year ended December 31, 2014, or the 2014 Form 10-K, filed with the SEC. The balance sheet amounts as of December 31, 2014 in this report were derived from the Company’s audited 2014 consolidated financial statements included in the 2014 Form 10-K.

The condensed consolidated financial statements reflect all adjustments of a normal and recurring nature that, in the opinion of management, are necessary to present fairly the Company’s financial position, results of operations and cash flows for the periods indicated. The preparation of the Company’s condensed consolidated financial statements in conformity with U.S. Generally Accepted Accounting Principles (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. The results of operations for the three and nine months ended September 30, 2015 and 2014, are not necessarily indicative of the results for the entire fiscal year or any future period.

The accompanying condensed consolidated financial statements of the Company and subsidiaries have been prepared on a basis which assumes that the Company will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities and commitments in the normal course of business. The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

As of September 30, 2015, the Company had cash and cash equivalents of $119.0 million. The Company’s condensed consolidated balance sheets also include derivative liabilities as well as long-term debt and exchangeable senior notes. The outstanding January 2012 exchangeable senior notes, or the 2012 Notes, and May 2014 exchangeable senior notes, or the 2014 Notes, may be redeemed on or after January 19, 2017 and January 19, 2019, respectively, at the option of the holders and it is not puttable by the holders prior to

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these dates except upon the occurrence of certain contingent events. The 2012 Notes are exchangeable under certain circumstances into cash, American Depository Shares, or ADSs, or a combination of cash and ADSs, at the Company’s election. The 2014 Notes are exchangeable under certain circumstances into ADSs. Accordingly, the long-term debt and exchangeable senior notes do not represent a short-term claim on the liquid assets of the Company.

The Company believes its cash and cash equivalents will be sufficient to fund its projected operations for at least the next twelve months.

Principles of Consolidation

The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Use of Estimates

Accounting estimates are based on historical experience and other factors that are considered reasonable under the circumstances. Estimates are used in determining such items as provisions for sales returns, rebates and incentives, chargebacks, and other sales allowances, depreciable/amortizable lives, asset impairments, valuation allowance on deferred taxes, probabilities of achievement of performance conditions for certain equity awards, amounts recorded for licensing revenue, contingencies and accruals, and valuations of derivative and long-term debt instruments. Because of the uncertainties inherent in such estimates, actual results may differ from these estimates. Management periodically evaluates estimates used in the preparation of the condensed consolidated financial statements for continued reasonableness.

Use of Forecasted Financial Information in Accounting Estimates

The use of forecasted financial information is inherent in many of the Company’s accounting estimates, including but not limited to, determining the estimated fair values of derivatives, debt instruments and intangible assets, and evaluating the need for valuation allowances for deferred tax assets. Such forecasted financial information is comprised of numerous assumptions regarding the Company’s future revenues, cash flows, and operational results. Management believes that its financial forecasts are reasonable and appropriate based upon current facts and circumstances. Because of the inherent nature of forecasts, however, actual results may differ from these forecasts. Management regularly reviews the information related to these forecasts and adjusts the carrying amounts of the applicable assets prospectively, if and when actual results differ from previous estimates.

Revenue Recognition

The Company sells Vascepa principally to a limited number of major wholesalers, as well as selected regional wholesalers and specialty pharmacy providers, or collectively, its Distributors, that in turn resell Vascepa to retail pharmacies for subsequent resale to patients and health care providers. Patients are required to have a prescription in order to purchase Vascepa. In accordance with GAAP, the Company’s revenue recognition policy requires that: (i) there is persuasive evidence that an arrangement exists between the Company and the Distributor, (ii) delivery has occurred, (iii) collectability is reasonably assured and (iv) the price is fixed or determinable.

The Company commenced its commercial launch in the United States in January 2013. Prior to 2013, the Company recognized no revenue from Vascepa sales. In accordance with GAAP, until the Company had the ability to reliably estimate returns of Vascepa from its Distributors, revenue was recognized based on the resale of Vascepa for the purposes of filling patient prescriptions, and not based on sales from the Company to such Distributors. Beginning in January 2014, the Company concluded that it had developed sufficient history such that it can reliably estimate returns and as a result, began to recognize revenue based on sales to its Distributors. The change in revenue recognition methodology resulted in the recognition of previously deferred revenue. As of December 31, 2013, the Company had deferred approximately $1.7 million in amounts billed to Distributors that was not recognized as revenue. This change in revenue recognition methodology resulted in the recognition of such deferred revenues in the three months ended March 31, 2014.

The Company has contracts with its primary Distributors and delivery occurs when a Distributor receives Vascepa. The Company evaluates the creditworthiness of each of its Distributors to determine whether revenues can be recognized upon delivery, subject to satisfaction of the other requirements, or whether recognition is required to be delayed until receipt of payment or when the product is utilized. In order to conclude that the price is fixed or determinable, the Company must be able to (i) calculate its gross product revenues from the sales to Distributors and (ii) reasonably estimate its net product revenues. The Company calculates gross product

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revenues based on the wholesale acquisition cost that the Company charges its Distributors for Vascepa. The Company estimates its net product revenues by deducting from its gross product revenues (a) trade allowances, such as invoice discounts for prompt payment and distributor fees, (b) estimated government and private payor rebates, chargebacks and discounts, such as Medicaid reimbursements, (c) reserves for expected product returns and (d) estimated costs of incentives offered to certain indirect customers, including patients.

Trade Allowances: The Company generally provides invoice discounts on Vascepa sales to its Distributors for prompt payment and pays fees for distribution services, such as fees for certain data that Distributors provide to the Company. The payment terms for sales to Distributors generally include a 2% discount for payment within 30 days while the fees for distribution services are based on contractual rates agreed with the respective Distributors. Based on judgment and experience, the Company expects its Distributors to earn these discounts and fees, and deducts the full amount of these discounts and fees from its gross product revenues and accounts receivable at the time such revenues are recognized.

Rebates, Chargebacks and Discounts: The Company contracts with Medicaid, other government agencies and various private organizations, or collectively, Third-party Payors, so that Vascepa will be eligible for purchase by, or partial or full reimbursement from, such Third-party Payors. The Company estimates the rebates, chargebacks and discounts it will provide to Third-party Payors and deducts these estimated amounts from its gross product revenues at the time the revenues are recognized. The Company estimates the rebates, chargebacks and discounts that it will provide to Third-party Payors based upon (i) the Company’s contracts with these Third-party Payors, (ii) the government-mandated discounts applicable to government-funded programs, (iii) information obtained from the Company’s Distributors and (iv) information obtained from other third parties regarding the payor mix for Vascepa.

Product Returns: The Company’s Distributors have the right to return unopened unprescribed Vascepa during the 18-month period beginning six months prior to the labeled expiration date and ending twelve months after the labeled expiration date. The expiration date for Vascepa is three years after it has been converted into capsule form, which is the last step in the manufacturing process for Vascepa and generally occurs within a few months before Vascepa is delivered to Distributors. As of September 30, 2015, the Company had experienced a de minimis quantity of product returns. The Company estimates future product returns on sales of Vascepa based on: (i) data provided to the Company by its Distributors (including weekly reporting of Distributors’ sales and inventory held by Distributors that provided the Company with visibility into the distribution channel in order to determine what quantities were sold to retail pharmacies and other providers), (ii) information provided to the Company from retail pharmacies, (iii) data provided to the Company by a third party data provider which collects and publishes prescription data, and other third parties, (iv) historical industry information regarding return rates for similar pharmaceutical products, (v) the estimated remaining shelf life of Vascepa previously shipped and currently being shipped to Distributors and (vi) contractual agreements intended to limit the amount of inventory maintained by the Company’s Distributors.

Other Incentives: Other incentives that the Company offers to indirect customers include co-pay mitigation rebates provided by the Company to commercially insured patients who have coverage for Vascepa and who reside in states that permit co-pay mitigation programs. The Company’s co-pay mitigation program is intended to reduce each participating patient’s portion of the financial responsibility for Vascepa’s purchase price to a specified dollar amount. Based upon the terms of the program and information regarding programs provided for similar specialty pharmaceutical products, the Company estimates the average co-pay mitigation amounts and the percentage of patients that it expects to participate in the program in order to establish its accruals for co-pay mitigation rebates and deducts these estimated amounts from its gross product revenues at the time the revenues are recognized. The Company adjusts its accruals for co-pay mitigation rebates based on actual redemption activity and estimates regarding the portion of issued co-pay mitigation rebates that it estimates will be redeemed.

The following table summarizes activity in each of the net product revenue allowance and reserve categories described above for the nine months ended September 30, 2015 (in thousands):

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Such net product revenue allowances and reserves are included within accrued expenses and other current liabilities within the condensed consolidated balance sheets, with the exception of trade allowances and chargebacks, which are included within accounts receivable, net as discussed below.

Multiple-Element Arrangements and Licensing Revenue

When evaluating multiple-element arrangements, the Company identifies the deliverables included within the agreement and evaluates which deliverables represent separate units of accounting based on whether the delivered element has stand-alone value to the customer or if the arrangement includes a general right of return for delivered items.

The consideration received is allocated between each of the separable elements in the arrangement using the relative selling price method. The selling price used for each separable element will be based on vendor specific objective evidence (“VSOE”) if available, third party evidence if VSOE is not available, or estimated selling price if neither VSOE nor third party evidence is available. Revenue is then recognized as each of the separable elements to which the revenue has been allocated is delivered.

The Company may receive up-front, non-refundable payments when licensing its intellectual property in conjunction with research, development and commercialization agreements. In determining the units of accounting, management evaluates whether the license has stand-alone value from the undelivered elements to the collaborative partner based on the consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination include the stage of development of the license delivered, research and development capabilities of the partner and the ability of partners to develop and commercialize Vascepa independent of the Company.

When management believes the license to its intellectual property does not have stand-alone value from the other deliverables to be provided in the arrangement, the Company generally recognizes revenue attributable to the license over the Company’s contractual or estimated performance period. Any unrecognized portion of license revenue is classified within deferred revenue in the accompanying condensed consolidated balance sheets. When management believes the license to its intellectual property has stand-alone value, the Company recognizes revenue attributed to the license upon delivery. The periods over which revenue is recognized is subject to estimates by management and may change over the course of the agreement. Such a change could have a material impact on the amount of revenue the Company records in future periods.

Milestones

Contingent consideration from activities that is earned upon the achievement of a substantive milestone is recognized in its entirety in the period in which the milestone is achieved. At the inception of each arrangement that includes milestone payments, the Company evaluates whether each milestone is substantive. This evaluation includes an assessment of whether: (a) the consideration is commensurate with either (1) the entity’s performance to achieve the milestone, or (2) the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the entity’s performance to achieve the milestone, (b) the consideration relates solely to past performance and (c) the consideration is reasonable relative to all of the deliverables and payment terms within the arrangement. The Company evaluates factors such as the scientific, clinical, regulatory, commercial and other risks that must be overcome to achieve the respective milestone, the level of effort and investment required and whether the milestone consideration is reasonable relative to all deliverables and payment terms in the arrangement in making this assessment.

Distribution Costs

The Company records distribution costs related to shipping product to its customers, primarily through the use of common carriers or external distribution services, in cost of goods sold.

Cash and Cash Equivalents

Cash and cash equivalents consist of cash, deposits with banks and short-term highly liquid money market instruments with remaining maturities at the date of purchase of 90 days or less. Restricted cash represents cash and cash equivalents pledged to guarantee repayment of certain expenses which may be incurred for business travel under corporate credit cards held by employees.

Accounts Receivable, net

Accounts receivable, net, comprised of trade receivables, are generally due within 30 days and are stated at amounts due from customers. The Company does not currently maintain an allowance for doubtful accounts and has not historically experienced any credit losses.

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The following table summarizes the impact of accounts receivable reserves on the gross trade accounts receivable balances as of September 30, 2015 and December 31, 2014 (in thousands):

Inventory

The Company states inventories at the lower of cost or market value. Cost is determined based on actual cost using the average cost method. An allowance is established when management determines that certain inventories may not be saleable. If inventory cost exceeds expected market value due to obsolescence, damage or quantities in excess of expected demand, the Company will reduce the carrying value of such inventory to market value. The Company received FDA approval for Vascepa on July 26, 2012 and after that date began capitalizing inventory purchases of saleable product from approved suppliers. Until an active pharmaceutical ingredient, or API, supplier is approved, all Vascepa API purchased from such supplier is included as a component of research and development expense. Upon sNDA approval of each additional supplier, the Company capitalizes subsequent Vascepa API purchases from such supplier as inventory. Purchases of Vascepa API received and expensed before such regulatory approvals is not subsequently capitalized, and all such purchases are quarantined and not used for commercial supply until such time as the sNDA for the supplier that produced the API is approved. The Company expenses inventory identified for use as marketing samples when they are packaged. The average cost reflects the actual purchase price of Vascepa API.

Property, Plant and Equipment

The Company provides for depreciation and amortization using the straight-line method by charges to operations in amounts that depreciate the cost of the fixed asset over its estimated useful life. The estimated useful lives, by asset classification, are as follows:

Upon retirement or sale of assets, the cost of the assets disposed and the related accumulated depreciation are removed from the balance sheet and any resulting gain or loss is credited or expensed to operations. Repairs and maintenance costs are expensed as incurred.

Long-Lived Asset Impairment

The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of these assets is determined by comparing the forecasted undiscounted net cash flows of the operation to which the assets relate to their carrying amount. If impairment is indicated, the assets are written down to fair value. Fair value is determined based on discounted forecasted cash flows or appraised values, depending on the nature of the assets.

Intangible Asset, net

Intangible assets consist of a milestone payment paid to the former shareholders of Laxdale Limited related to the 2004 acquisition of the rights to Vascepa, which is the result of Vascepa receiving marketing approval for the first indication and is amortized over its estimated useful life on a straight-line basis. See Note 7—Commitments and Contingencies for further information regarding other obligations related to the acquisition of Laxdale Limited.

Beneficial Conversion Features

The Company issued Series A preference shares in a private placement transaction executed in two tranches that each contain a conversion feature whereby such shares are convertible into ordinary shares at a fixed rate. The conversion price on the date of issuance was less than the market price of the Company’s ordinary shares. It was determined that these discounts represent contingent beneficial conversion features, which were valued based on the difference between the conversion price and the market price of the

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ordinary shares on the date of issuance, which is the commitment date. These features are analogous to preference dividends and were each recorded as a non-cash return to preferred shareholders through accumulated deficit upon the earliest possible date of conversion, which occurred in the three months ended June 30, 2015 upon effectiveness of the related resale Registration Statement on Form S-3 and in the three months ended September 30, 2015 upon shareholder approval received at the Company’s Annual General Meeting of Shareholders. See Note 8—Equity for further discussion.

Costs for Patent Litigation and Legal Proceedings

Costs for patent litigation or other legal proceedings are expensed as incurred and included in selling, general and administrative expenses.

Research and Development Costs

The Company charges research and development costs to operations as incurred. Research and development expenses are comprised of costs incurred by the Company in performing research and development activities, including: salary and benefits; stock-based compensation expense; laboratory supplies and other direct expenses; contractual services, including clinical trial and pharmaceutical development costs; commercial supply investment in its drug candidates; and infrastructure costs, including facilities costs and depreciation expense. In addition, research and development costs include the costs of product supply received from suppliers when such receipt by the Company is prior to regulatory approval of the supplier.

Selling, General and Administrative Costs

The Company charges selling, general and administrative costs to operations as incurred. Selling, general and administrative costs include costs of salaries, programs and infrastructure necessary for the general conduct of the Company’s business, including those incurred as a result of the commercialization of Vascepa in the United States as well as co-promotion fees payable to Kowa Pharmaceuticals America, Inc.

Income Taxes

Deferred tax assets and liabilities are recognized for the future tax consequences of differences between the carrying amounts and tax bases of assets and liabilities and operating loss carryforwards and other attributes using enacted rates expected to be in effect when those differences reverse. Valuation allowances are provided against deferred tax assets that are not more likely than not to be realized.

The Company provides reserves for potential payments of tax to various tax authorities or does not recognize tax benefits related to uncertain tax positions and other issues. Tax benefits for uncertain tax positions are based on a determination of whether a tax benefit taken by the Company in its tax filings or positions is more likely than not to be realized, assuming that the matter in question will be decided based on its technical merits. The Company’s policy is to record interest and penalties in the provision for income taxes.

The Company regularly assesses the realizability of deferred tax assets. Changes in historical earnings performance and future earnings projections, among other factors, may cause the Company to adjust its valuation allowance on deferred tax assets, which would impact the Company’s income tax expense in the period in which it is determined that these factors have changed.

Derivative Instruments

Derivative financial liabilities are recorded at fair value, with gains and losses arising for changes in fair value recognized in the statement of operations at each period end while such instruments are outstanding. If the Company issues shares to discharge the liability, the derivative financial liability is derecognized and common stock and additional paid-in capital are recognized on the issuance of those shares. The warrants are valued using a Black-Scholes option pricing model due to the nature of instrument. The long-term debt redemption features are valued using probability-weighted models incorporating management estimates for potential change in control, and by determining the fair value of the debt with and without the change in control provision included.

If the terms of warrants that initially require the warrant to be classified as a derivative financial liability lapse, the derivative financial liability is reclassified out of financial liabilities into equity at its fair value on that date. The cash proceeds received from exercises of warrants are recorded in common stock and additional paid-in capital.

Loss per Share

Basic net loss per share is determined by dividing net loss by the weighted average shares of common stock outstanding during the period. Diluted net loss per share is determined by dividing net loss by diluted weighted average shares outstanding. Diluted weighted average shares reflects the dilutive effect, if any, of potentially dilutive common shares, such as common stock options and warrants

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calculated using the treasury stock method and convertible notes using the “if-converted” method. In periods with reported net operating losses, all common stock options and warrants are deemed anti-dilutive such that basic net loss per share and diluted net loss per share are equal. However, in certain periods in which there is a gain recorded pursuant to the change in fair value of the warrant derivative liability, for diluted net loss per share purposes, the impact of such gains is reversed and the treasury stock method is used to determine diluted net loss per share.

The Company’s preferred stock is entitled to receive dividends on an as-if-converted basis in the same form as dividends actually paid on common shares. Accordingly, the preferred stock is considered a participating security and the Company is required to apply the two-class method to consider the impact of the preferred stock on the calculation of basic and diluted earnings per share. The Company is currently in a net loss position and is therefore not required to present the two-class method, however, in the event the Company is in a net income position, the two-class method must be applied by allocating all earnings during the period to common shares and preferred stock based on their contractual entitlements assuming all earnings were distributed.

The calculation of net loss and the number of shares used to compute basic and diluted net loss per share for the three and nine months ended September 30, 2015 and 2014 are as follows:

For the three and nine months ended September 30, 2015 and 2014, the following potentially dilutive securities were not included in the computation of net loss per share because the effect would be anti-dilutive:

Debt Instruments

Debt instruments are initially recorded at fair value, with coupon interest and amortization of debt issuance discounts recognized in the statement of operations as interest expense each period in which such instruments are outstanding. If the Company issues shares to discharge the liability, the debt obligation is derecognized and common stock and additional paid-in capital are recognized on the issuance of those shares. The conversion features in both the 2012 Notes and 2014 Notes qualify for the exception from derivative accounting in accordance with ASC 815-40. The 2012 Notes may be settled, at the Company’s discretion, in any combination of ADSs or cash upon conversion and have been accounted for in accordance with ASC 470-20. Under ASC 470-20, the fair value of the liability component of the 2012 Notes was determined and deducted from the initial proceeds to determine the proceeds allocated to the conversion option, which has been recorded in equity. The difference between the initial fair value of the liability component and the amount repayable is amortized over the expected term of the instrument. The conversion feature in the 2014 Notes may only be settled in ADSs upon conversion and has been accounted for as part of the debt host.

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The conversion options in both the 2012 Notes and 2014 Notes continue to be evaluated on a quarterly basis to determine if they still receive an exception from derivative accounting in accordance with ASC 815-40. The 2014 Notes were recognized initially at fair value as part of an extinguishment of a portion of the 2012 Notes (see further discussion in Note 6). As a result, the debt was initially recognized at a discount of $27.9 million. This discount will be amortized through interest expense over the expected term of the note.

Stock-Based Compensation

Stock-based compensation cost is generally measured at the grant date, based on the fair value of the award, and is recognized as compensation expense over the requisite service period. For awards with performance conditions, if the achievement of the performance conditions is deemed probable, the Company recognizes compensation expense based on the fair value of the award over the estimated service period. The Company reassesses the probability of achievement of the performance conditions for such awards each reporting period.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to credit risk consist primarily of cash and cash equivalents and accounts receivable. The Company maintains substantially all of its cash and cash equivalents in financial institutions believed to be of high-credit quality.

A significant portion of the Company’s sales are to wholesalers in the pharmaceutical industry. The Company monitors the creditworthiness of customers to whom it grants credit terms and has not experienced any credit losses. The Company does not require collateral or any other security to support credit sales. The Company’s top three customers accounted for 95% of gross product sales for each of the nine months ended September 30, 2015 and 2014, and represented 95% and 96% of the gross accounts receivable balance as of September 30, 2015 and 2014, respectively. The Company has not experienced any write-offs of its accounts receivable.

Concentration of Suppliers

The Company has contractual freedom to source the API for Vascepa and has entered into supply agreements with multiple suppliers. The Company’s supply of product for commercial sale and clinical trials is dependent upon relationships with third party manufacturers and key suppliers, in particular three suppliers of API for Vascepa.

The Company cannot provide assurance that its efforts to procure uninterrupted supply of Vascepa API to meet market demand will continue to be successful or that it will be able to renew current API supply agreements on favorable terms or at all. Significant alteration to or termination of the Company’s current API supply chain or its failure to enter into new and similar agreements, if needed, could have a material adverse effect on its business, condition (financial and other), prospects or results of operations.

The Company currently has manufacturing agreements with three FDA-approved commercial API encapsulators for Vascepa manufacturing. Each of these companies has qualified its manufacturing processes and is capable of manufacturing Vascepa. There can be no guarantee that these or other suppliers with which the Company may contract in the future to encapsulate API will continue to be qualified to manufacture the product to its specifications or that these and any future suppliers will have the manufacturing capacity to meet anticipated demand for Vascepa.

Foreign Currency

All subsidiaries use the U.S. dollar as the functional currency. Monetary assets and liabilities denominated in a foreign currency are remeasured into U.S. dollars at period-end exchange rates. Gains and losses from the remeasurement are included in other (expense) income, net in the condensed consolidated statements of operations. For transactions settled during the applicable period, gains and losses are included in other (expense) income, net in the condensed consolidated statements of operations. Certain supply contracts are denominated in currencies other than the U.S. dollar.

Debt Issuance Costs

Debt issuance costs are initially recorded as a deferred cost and amortized to interest expense using the effective interest method over the expected term of the related debt. Unamortized debt issuance costs related to extinguishment of debt are expensed at the time the debt is extinguished and recorded in other (expense) income, net in the condensed consolidated statements of operations.

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Fair Value of Financial Instruments

The Company provides disclosure of financial assets and financial liabilities that are carried at fair value based on the price that would be received upon sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value measurements may be classified based on the amount of subjectivity associated with the inputs to fair valuation of these assets and liabilities using the following three levels:

Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2—Inputs include quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (i.e., interest rates, yield curves, etc.) and inputs that are derived principally from or corroborated by observable market data by correlation or other means (market corroborated inputs).

Level 3—Unobservable inputs that reflect the Company’s estimates of the assumptions that market participants would use in pricing the asset or liability. The Company develops these inputs based on the best information available, including its own data.

The following tables present information about the Company’s assets and liabilities as of September 30, 2015 and December 31, 2014 that are measured at fair value on a recurring basis and indicate the fair value hierarchy of the valuation techniques the Company utilized to determine such fair value:

The carrying amounts of cash, cash equivalents, accounts payable and accrued liabilities approximate fair value because of their short-term nature. The carrying amounts and the estimated fair values of debt instruments as of September 30, 2015 and December 31, 2014 are as follows:

The estimated fair value of the long-term debt pursuant to the December 2012 financing is calculated utilizing the same Level 3 inputs utilized in valuing the related derivative liability (see Long-Term Debt Redemption Features below). The estimated fair value of the 2012 Notes and 2014 Notes is calculated based on Level 1 quoted bond prices. The carrying value of the 2012 Notes as of September 30, 2015 and December 31, 2014 does not include a debt discount, as it had been fully amortized as non-cash interest expense over the expected term of the 2012 Notes. The carrying value of the 2014 Notes as of September 30, 2015 and December 31, 2014 includes a debt discount of $23.9 million and $28.2 million, respectively, which is being amortized as non-cash interest expense over the expected term of the 2014 Notes. The change in the estimated fair values of these liabilities from December 31, 2014 to September 30, 2015 is largely related to changes in the quoted bond prices.

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Derivative Liabilities

Warrant Derivative Liability

The Company’s warrant derivative liability is carried at fair value and is classified as Level 3 in the fair value hierarchy due to the use of significant unobservable inputs. Effective October 16, 2014, the Company entered into a series of warrant amendment agreements in order to extend the expiration date of certain outstanding warrants from its previously scheduled expiration date of October 16, 2014 to the close of business on February 27, 2015. Of the 8,087,388 warrants outstanding as of December 31, 2014, 1,844,585 warrants were exercised and the remaining 6,242,803 warrants expired on February 27, 2015. As such, no warrants were outstanding as of September 30, 2015 and the related derivative liability was extinguished.

As of December 31, 2014, the fair value of the warrant derivative liability was determined to be $0.1 million using the Black-Scholes option valuation model applying the following assumptions: (i) risk-free rate of 0.04%, (ii) remaining term of 0.16 years, (iii) no dividend yield, (iv) volatility of 79%, and (v) the stock price on the date of measurement. As there were no warrants outstanding as of September 30, 2015, the warrant derivative liability was extinguished. The $0.1 million decrease in the fair value of the warrants during the nine months ended September 30, 2015 was recognized as a $0.1 million gain on change in fair value of derivative liability.

Long-Term Debt Redemption Features

The Company’s December 2012 financing agreement with BioPharma Secured Debt Fund II Holdings Cayman LP (discussed in Note 6 below) contains a redemption feature whereby, upon a change of control, the Company would be required to repay $150 million, less any previously repaid amount. The Company determined this redemption feature to be an embedded derivative, which is carried at fair value and is classified as Level 3 in the fair value hierarchy due to the use of significant unobservable inputs. The fair value of the embedded derivative was calculated using a probability-weighted model incorporating management estimates of future revenues and for a potential change in control, and by determining the fair value of the debt with and without the change in control provision included. The difference between the two was determined to be the fair value of the embedded derivative. As of September 30, 2015, the fair value of the derivative was determined to be $5.1 million, and the debt was valued by comparing debt issues of similar companies with (i) remaining terms of between 2.3 and 5.4 years, (ii) coupon rates of between 8.9% and 12.5% and (iii) market yields of between 10.5% and 18.8%. The Company recognized a $0.3 million loss on change in fair value of derivative liability for the nine months ended September 30, 2015. As of December 31, 2014, the fair value of the derivative was determined to be $4.8 million, and the debt was valued by comparing debt issues of similar companies with (i) remaining terms of between 2.3 and 3.6 years, (ii) coupon rates of between 9.8% and 10.8% and (iii) market yields of between 10.0% and 16.8%.

The Company’s 2014 Notes contain a redemption feature whereby, upon occurrence of a change in control, the Company would be required to repurchase the notes. The Company determined this redemption feature to be an embedded derivative, requiring bifurcation in accordance with ASC 815. The derivative is carried at fair value and is classified as Level 3 in the fair value hierarchy due to the use of significant unobservable inputs. The fair value of the embedded derivative was calculated using a probability-weighted model incorporating management estimates of the probability of a change in control occurring, and by determining the fair value of the debt with and without the change in control provision included. The difference between the two was determined to be the fair value of the embedded derivative. As of September 30, 2015, the fair value of the derivative was determined to be $1.8 million, and the debt was valued by using (i) the estimated remaining term of the notes, (ii) a bond yield of 22.9%, (iii) a risk-free interest rate of 2.7% and (iv) volatility of 83.0%. The Company recognized a $0.8 million gain on change in fair value of derivative liability for the nine months ended September 30, 2015. As of December 31, 2014, the fair value of the derivative was determined to be $2.6 million, and the debt was valued by using (i) the estimated remaining term of the notes, (ii) a bond yield of 24.8%, (iii) a risk-free interest rate of 2.7% and (iv) volatility of 82.0%.

Preferred Stock Purchase Option Derivative Liability

Pursuant to a pre-existing contractual right to participate in certain private placement transactions effected by the Company in connection with the subscription agreement executed on March 5, 2015, the Company determined that such right represented a derivative liability (see Note 8). This preferred stock purchase option derivative liability was carried at fair value and classified as Level 3 in the fair value hierarchy due to the use of significant unobservable inputs. The fair value of this liability was calculated using a Black-Scholes model and was determined to be $0.9 million at inception. On March 30, 2015, this right was exercised and the liability was marked to fair value through such date. The liability was then reclassified to permanent equity on such date.

Any changes in the assumptions used to value the derivative liabilities, including the probability of a change in control, could result in a material change to the carrying value of such liabilities.

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The change in the fair value of derivative liabilities for the nine months ended September 30, 2015 and 2014 is as follows (in thousands):

Segment and Geographical Information

Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated on a regular basis by the chief operating decision-maker, or decision-making group, in deciding how to allocate resources to an individual segment and in assessing performance of the segment. The Company currently operates in one business segment, which is the development and commercialization of Vascepa. A single management team that reports to the Company’s chief decision-maker, who is the Chief Executive Officer, comprehensively manages the business. Accordingly, the Company does not have separately reportable segments.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board, or FASB, and are adopted by the Company as of the specified effective date. The Company considered the following recent accounting pronouncements which were not yet adopted as of September 30, 2015:

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). This amendment provides principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services, and is effective for annual periods beginning after December 15, 2016 (the original effective date). In April 2015, the FASB issued a proposal, which was subsequently adopted in July 2015, to defer the original effective date of this standard by one year, such that the amendment is effective for the Company’s fiscal year beginning January 1, 2018. Early adoption is permitted, but not before the original effective date. The Company is currently evaluating the accounting, transition and disclosure requirements of the standard and cannot currently estimate the financial statement impact of adoption.

In June 2014, the FASB issued guidance for accounting for share-based payments when the terms of an award provide that a performance target could be achieved after the requisite service period. The standard states that a performance target in a share-based payment that affects vesting and that could be achieved after the requisite service period should be accounted for as a performance condition. As such, the performance target should not be reflected in estimating the grant-date fair value of the award. The Company is required to adopt this standard in the first quarter of fiscal 2016 and early adoption is permitted. This standard is not expected to have an impact on the Company’s condensed consolidated financial statements.

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In August 2014, the FASB issued ASU No. 2014-15, Presentation of Financial Statements—Going Concern, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40). ASU 2014-15 requires management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards. Specifically, the ASU (i) provides a definition of the term substantial doubt, (ii) requires an evaluation every reporting period including interim periods, (iii) provides principles for considering the mitigating effect of management’s plans, (iv) requires certain disclosures when substantial doubt is alleviated as a result of consideration of management’s plans, (v) requires an express statement and other disclosures when substantial doubt is not alleviated and (vi) requires an assessment for a period of one year after the date that the financial statements are issued (or available to be issued). This standard is effective for fiscal years ending after December 15, 2016, and for annual and interim periods thereafter. Early application is permitted. The Company is currently evaluating the accounting, transition and disclosure requirements of the standard and cannot currently estimate the financial statement impact of adoption.

In April 2015, the FASB issued ASU No. 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The amendments in this ASU require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The Company is required to adopt this standard in the first quarter of fiscal 2016 on a retrospective basis. The implementation of this standard will result in the reclassification of certain debt issuance costs from other assets to a reduction in the carrying amount of the related debt liability within the condensed consolidated balance sheets.

In July 2015, the FASB issued Accounting Standards Update (ASU) No, 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. The amendments in this ASU require that in-scope inventory should be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The amendments do not apply to inventory that is measured using last-in, first-out (LIFO) or the retail inventory method but applies to all other inventory, which include inventory that is measured using first-in, first-out (FIFO) or average cost. This standard is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early application is permitted. The Company is currently evaluating the accounting, transition and disclosure requirements of the standard and cannot currently estimate the financial statement impact of adoption.

The Company believes that the impact of other recently issued but not yet adopted accounting pronouncements will not have a material impact on condensed consolidated financial position, results of operations, and cash flows, or do not apply to the Company’s operations.

Intangible assets consist of the historical acquisition cost of certain technology rights for Vascepa and have an estimated remaining useful life of 14.8 years. The carrying value as of September 30, 2015 and December 31, 2014 is as follows (in thousands):

After approval of Vascepa on July 26, 2012 by the FDA, the Company began capitalizing its purchases of saleable inventory of Vascepa from suppliers that have been qualified by the FDA. Inventories as of September 30, 2015 and December 31, 2014 consist of the following (in thousands):

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October 2009 Warrants Derivative Liability

On October 16, 2009, the Company completed a $70.0 million private placement with both existing and new investors resulting in $62.3 million in net proceeds and an additional $3.6 million from bridge notes converted in conjunction with the private placement. In consideration for the $62.3 million in net cash proceeds Amarin issued 66.4 million units, each unit consisting of (i) one ADS (representing one ordinary share) at a purchase price of $1.00 and (ii) a warrant with a five year term to purchase 0.5 of an ADS at an exercise price of $1.50 per ADS. In consideration for the conversion of $3.6 million of convertible bridge notes, Amarin issued 4.0 million units, each unit consisting of (i) one ADS (representing one ordinary share) at a purchase price of $0.90 and (ii) a warrant with a five year term to purchase 0.5 of an ADS at an exercise price of $1.50 per ADS. The total number of warrants issued in conjunction with the financing was 35.2 million.

In conjunction with the October 2009 financing, the Company issued an additional 0.9 million warrants to three former officers. The warrants issued in connection with the October 2009 financing contained a pricing variability feature which provided for an increase to the exercise price if the exchange rate between the U.S. dollar and British pound adjusts such that the warrants could be exercised at a price less than the £0.5 par value of the common stock—that is, if the exchange rate exceeded U.S. $3.00 per £1.0 sterling. Due to the potential variable nature of the exercise price, the warrants are not considered to be indexed to the Company’s common stock. Accordingly, the warrants do not qualify for the exception to classify the warrants within equity and are classified as a derivative liability.

The fair value of this warrant derivative liability is remeasured at each reporting period, with changes in fair value recognized in the statement of operations. Upon exercise, the fair value of the warrants exercised is remeasured and reclassified from warrant derivative liability to additional paid-in-capital. Although the warrants contain a pricing variability feature, the number of warrants issuable remains fixed. Therefore, the maximum number of common shares issuable as a result of the October 2009 private placement is 36.1 million. The change in fair value of the warrant derivative liability is discussed in Note 2.

In October 2014, the Company and the holders of the remaining October 2009 warrants mutually agreed to extend the expiration date of such warrants from October 16, 2014 to February 27, 2015. Of the 8,087,388 warrants outstanding as of December 31, 2014, 1,844,585 warrants were exercised, resulting in net proceeds to the Company of $2.7 million, and the remaining 6,242,803 warrants expired on February 27, 2015. As such, no warrants were outstanding as of September 30, 2015.

July 2009 Warrants

The Company issued several warrants in July 2009. As of September 30, 2015 and December 31, 2014, there were no July 2009 warrants outstanding. During the year ended December 31, 2014, 1,684,888 of the July 2009 warrants were exercised, resulting in proceeds to the Company of $1.7 million.

Long-Term Debt—December 2012 Financing

On December 6, 2012, the Company entered into an agreement with BioPharma Secured Debt Fund II Holdings Cayman LP, or BioPharma. Under this agreement, the Company granted to BioPharma a security interest in future receivables associated with the Vascepa patent rights, in exchange for $100 million received at the closing of the agreement which occurred in December 2012. Under these terms, the Company continues to own all Vascepa intellectual property rights, however, such rights, as described below, could be used by BioPharma as collateral for repayment of the remaining unpaid balance under this agreement if the Company defaults on making required payments under the agreement. In the agreement, the Company agreed to repay BioPharma up to $150 million with such repayment based on a portion of revenues and receivables generated from Vascepa after the date of the agreement.

As of September 30, 2015, the remaining amount to be repaid to BioPharma is $139.4 million. During the three and nine months ended September 30, 2015, the Company made repayments under the agreement of $1.8 million and $5.0 million, respectively, to BioPharma and an additional $2.1 million is scheduled to be paid in November 2015. These payments were calculated based on the threshold limitation, as described below, as opposed to the scheduled quarterly repayments. Additional quarterly repayments, subject to the threshold limitation, are scheduled to be paid.

The maximum quarterly amounts which could be due for payment, except upon a change of control and subject each quarter to the threshold limitation, is in accordance with the following schedule: $10.0 million in the first quarter of 2016, $15.0 million per quarter in each of the next four quarters, and a final payment of $13.0 million scheduled for payment in May 2017. All such payments reduce the remainder of the $150 million in aggregate payments to BioPharma. These quarterly payments are subject to a quarterly threshold amount whereby, if a calculated threshold, based on quarterly Vascepa revenues, is not achieved, the quarterly payment payable in that quarter can at the Company’s election be reduced and with the reduction carried forward without interest for payment in a future

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period. The payment of any carried forward amount is subject to similarly calculated threshold repayment amounts based on Vascepa revenue levels. Except upon a change of control in Amarin, the agreement does not expire until $150 million in aggregate has been repaid. Except in the event of the Company’s default, there is no compounding of interest and no scheduled cliff payment due under this agreement. Rather, payment is intended, subject to the threshold limitation, until $150 million in aggregate has been repaid, including payments made previously. The Company can prepay an amount equal to $150 million less any previously repaid amount.

The Company currently estimates that its Vascepa revenue levels will not be high enough in each quarter to support repayment to BioPharma in accordance with the maximum quarterly amounts in the repayment schedule. For each quarterly period since the inception of the debt, revenues were below the contractual threshold amount such that cash payments were calculated for each period reflecting the optional reduction amount as opposed to the contractual threshold payment due for each quarterly period. In accordance with the agreement with BioPharma, quarterly differences between the calculated optional reduction amounts and the repayment schedule amounts are rescheduled for payment beginning in the second quarter of 2017. Any such deferred repayments will remain subject to continued application of the quarterly ceiling in amounts due established by the calculated threshold limitation based on quarterly Vascepa revenues. No additional interest expense or liability is incurred as a result of such deferred repayments. These estimates will be reevaluated each reporting period by the Company and adjusted if necessary, prospectively.

The Company determined the redemption feature upon a change of control to be an embedded derivative requiring bifurcation. The fair value of the embedded derivative was calculated by determining the fair value of the debt with the change in control provision included and also without the change in control provision. The difference between the two fair values of the debt was determined to be the fair value of the embedded derivative, and upon closing the Company recorded a derivative liability of $14.6 million as a reduction to the note payable. The fair value of this derivative liability is remeasured at each reporting period, with changes in fair value recognized in the statement of operations and any changes in the assumptions used in measuring the fair value of the derivative liability could result in a material increase or decrease in its carrying value. The Company recognized a loss on change in fair value of derivative liability of $0.3 million and a gain on change in fair value of derivative liability of $6.5 million during the nine months ended September 30, 2015 and 2014, respectively.

During the nine months ended September 30, 2015, the Company recorded $4.9 million and $1.4 million of cash and non-cash interest expense, respectively, in connection with the BioPharma debt. During the nine months ended September 30, 2014, the Company recorded $5.5 million and $1.4 million of cash and non-cash interest expense, respectively. The Company will periodically evaluate the remaining term of the agreement and the effective interest will be recalculated each period based on the Company’s most current estimate of repayment.

To secure the obligations under the agreement with BioPharma, the Company granted BioPharma a security interest in the Company’s patents, trademarks, trade names, domain names, copyrights, know-how and regulatory approvals related to the covered products, all books and records relating to the foregoing and all proceeds of the foregoing, referred to collectively as the collateral. If the Company (i) fails to deliver a payment when due and does not remedy that failure within a specific notice period, (ii) fails to maintain a first-priority perfected security interest in the collateral in the United States and does not remedy that failure after receiving notice of such failure or (iii) becomes subject to an event of bankruptcy, then BioPharma may attempt to collect the maximum amount payable by the Company under this agreement (after deducting any payments the Company has already made).

January 2012 Exchangeable Senior Notes

In January 2012, the Company issued $150.0 million in principal amount of 3.5% exchangeable senior notes due 2032, a portion of which were subsequently exchanged (see discussion of May 2014 Exchangeable Senior Notes below). The 2012 Notes were issued by Corsicanto Limited, an Irish limited company acquired by Amarin in January 2012. Corsicanto Limited is a wholly-owned subsidiary of Amarin. The general, unsecured, senior obligations are fully and unconditionally guaranteed by Amarin but not by any of the Company’s other subsidiaries. Corsicanto Limited has no assets, operations, revenues or cash flows other than those related to the issuance, administration and repayment of the 2012 Notes and 2014 Notes. There are no significant restrictions on the ability of Amarin to obtain funds from Corsicanto Limited in the form of cash dividends, loans, or advances. Net proceeds to the Company, after payment of underwriting fees and expenses, were approximately $144.3 million.

The 2012 Notes have a stated interest rate of 3.5% per year, payable semiannually in arrears on January 15 and July 15 of each year beginning on July 15, 2012, and ending upon the 2012 Notes’ maturity on January 15, 2032. The 2012 Notes are subject to repurchase by the Company at the option of the holders on each of January 19, 2017, January 19, 2022, and January 19, 2027, at a price equal to 100% of the principal amount of the 2012 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the repurchase date. The 2012 Notes are exchangeable under certain circumstances into cash, ADSs, or a combination of cash and ADSs, at the Company’s election, with an initial exchange rate of 113.4752 ADSs per $1,000 principal amount of 2012 Notes (equivalent to an initial exchange price of approximately $8.8125 per ADS), subject to adjustment in certain circumstances, including adjustment if the Company pays cash dividends. If the Company elected physical settlement, the net remaining outstanding portion of the 2012 Notes would be exchangeable into 3,547,916 ADSs after the May 2014 exchange of a portion of the 2012 Notes (see below for further discussion of the May 2014 exchange). Based on the closing price of the Company’s stock as of September 30, 2015, the principal amount of the 2012 Notes would exceed the value of the shares if converted on that date by $24.4 million.

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Additional covenants include: (i) limitations on future indebtedness under certain circumstances, (ii) the timely filing of documents and reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 with both the SEC and the Trustee and (iii) maintaining the tradability of the 2012 Notes. The Company is required to use commercially reasonable efforts to procure and maintain the listing of the 2012 Notes on the Global Exchange Market operated under the supervision of the Irish Stock Exchange (or other recognized stock exchange as defined in the Note Indenture) prior to July 15, 2012. If the 2012 Notes are not freely tradable, as a result of restrictions pursuant to U.S. securities law or the terms of the Indenture or the 2012 Notes, the Company shall pay additional interest on the 2012 Notes at the rate of 0.50% per annum of the principal amount of 2012 Notes outstanding for each day during such period for which the Company’s failure to file has occurred and is continuing or for which the 2012 Notes are not freely tradable.

The Company may not redeem the 2012 Notes prior to January 19, 2017, other than in connection with certain changes in the tax law of a relevant taxing jurisdiction that results in additional amounts becoming due with respect to payments and/or deliveries on the 2012 Notes. On or after January 19, 2017 and prior to the maturity date, the Company may redeem for cash all or part of the 2012 Notes at a redemption price equal to 100% of the principal amount of the 2012 Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. There is no prepayment penalty or sinking fund provided for the 2012 Notes. If the Company undergoes a change in control, holders may require the Company to repurchase for cash all or part of their 2012 Notes at a repurchase price equal to 100% of the principal amount of the 2012 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the change in control repurchase date. The 2012 Notes are the Company’s senior unsecured obligations and rank senior in right of payment to the Company’s future indebtedness that is expressly subordinated in right of payment to the 2012 Notes and equal in right of payment to the Company’s future unsecured indebtedness that is not so subordinated. The 2012 Notes are effectively junior in right of payment to future secured indebtedness to the extent of the value of the assets securing such indebtedness.

The 2012 Notes are exchangeable under certain circumstances. At the time of issuance, the Company calculated the fair value of the liability component of the outstanding 2012 Notes to be $126.2 million, and the excess of the principal amount of the debt over the liability component of $23.8 million was allocated to the conversion option resulting in a discount on the debt and corresponding increase in equity as a result of the cash settlement feature. The discount created from allocating proceeds to the conversion option was amortized to interest expense using the effective interest method over the 2012 Notes’ estimated remaining life, which was calculated to be a period of twenty-four months. As of September 30, 2015 and December 31, 2014, the discount created from the allocation of the proceeds to the conversion option was fully amortized. The conversion option will not be subsequently remeasured as long as it continues to meet the criteria for equity classification.

The Company also recorded a debt discount to reflect the value of the underwriter’s discounts and offering costs. A portion of the debt discount from underwriter’s discounts and offering costs was allocated to the equity and liability components of the 2012 Notes in proportion to the proceeds allocated to each component. The portion of the debt discount from underwriter’s discounts and offering costs allocated to the liability component was amortized as interest expense over the estimated life of the 2012 Notes of twenty-four months. As of September 30, 2015 and December 31, 2014, the debt discount was fully amortized and the carrying value of the 2012 Notes was $31.3 million after an exchange of a portion of the 2012 Notes (see below for further discussion of the May 2014 exchange).

May 2014 Exchangeable Senior Notes

In May 2014, the Company entered into separate, privately negotiated exchange agreements with certain holders of the 2012 Notes pursuant to which Corsicanto exchanged $118.7 million in aggregate principal amount of the existing 2012 Notes for $118.7 million in aggregate principal amount of new 3.50% May 2014 Exchangeable Senior Notes due 2032, following which $31.3 million in aggregate principal amount of the 2012 Notes remained outstanding with terms unchanged (the 2012 Notes and 2014 Notes are referred to collectively as the “Notes”).

The 2014 Notes have a stated interest rate of 3.5% per year, payable semiannually in arrears on January 15 and July 15 of each year beginning on July 15, 2014, and ending upon the 2014 Notes’ maturity on January 15, 2032, unless earlier repurchased or redeemed by Corsicanto or exchanged by the holders. At any time after the issuance of the 2014 Notes and prior to the close of business on the second business day immediately preceding January 15, 2032, holders may exchange the 2014 Notes at their option. If prior to January 15, 2018, a make-whole fundamental change (as defined in the Indenture) occurs or the Company elects to redeem the 2014 Notes in connection with certain changes in tax law, in each case as described in the Indenture, and a holder elects to exchange its 2014 Notes in connection with such make-whole fundamental change or election, as the case may be, such holder may be entitled to an increase in the exchange rate as described in the Indenture. In the event of physical settlement, the 2014 Notes would be exchangeable into 45,666,925 ADSs. The initial exchange rate is 384.6154 ADSs per $1,000 principal amount of the 2014 Notes (equivalent to an initial exchange price of approximately $2.60 per ADS, or the Exchange Price), subject to adjustment in certain

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circumstances. The exchange rate is subject to adjustment from time to time upon the occurrence of certain events, including, but not limited to, the payment of cash dividends. Based on the closing price of the Company’s stock as of September 30, 2015, the principal amount of the 2014 Notes would exceed the value of the shares if converted on that date by $30.6 million.

Prior to January 19, 2018, the Company may not redeem the 2014 Notes at its option other than in connection with certain changes in the tax law of a relevant taxing jurisdiction that results in additional amounts (as defined in the Indenture) becoming due with respect to payments and/or deliveries on the 2014 Notes. On or after January 19, 2018, the Company may redeem for cash all or a portion of the 2014 Notes at a redemption price of 100% of the aggregate principal amount of the 2014 Notes to be redeemed, plus accrued and unpaid interest to, but not including, the redemption date. If a fundamental change (as defined in the Indenture) occurs, holders may require the Company to repurchase all or part of their 2014 Notes for cash at a fundamental change repurchase price equal to 100% of the aggregate principal amount of the 2014 Notes to be repurchased, plus accrued and unpaid interest to, but not including, the fundamental change repurchase date. In addition, holders of the 2014 Notes may require the Company to repurchase all or any portion of the 2014 Notes on each of January 19, 2019, January 19, 2024 and January 19, 2029 for cash at a price equal to 100% of the aggregate principal amount of the 2014 Notes to be repurchased, plus accrued and unpaid interest to, but not including, the repurchase date.

The Company may elect at its option to cause all or any portion of the 2014 Notes to be mandatorily exchanged in whole or in part at any time prior to the close of business on the business day preceding January 15, 2032 if the Daily VWAP (as defined in the Indenture) equals or exceeds 110% of the Exchange Price then in effect for at least 20 VWAP Trading Days (as defined in the Indenture) in any 30 VWAP Trading Day period. The Company may only exercise its optional exchange rights upon satisfaction of specified equity conditions, including that the ADSs issuable upon exchange of the 2014 Notes be eligible for resale without registration by non-affiliates and listed on The NASDAQ Global Market, its related exchanges or the New York Stock Exchange. If Corsicanto elects to exercise its optional exchange rights on or prior to January 15, 2018, each holder whose 2014 Notes are exchanged will upon exchange receive a specified number of additional ADSs as set forth in the Indenture. Upon such a declaration of acceleration, such principal and accrued and unpaid interest, if any, will be due and payable immediately. Upon the occurrence of certain events of bankruptcy, insolvency or reorganization involving Corsicanto, 100% of the principal of and accrued and unpaid interest, if any, on all of the 2014 Notes will become due and payable automatically. Notwithstanding the foregoing, the Indenture will provide that, to the extent Corsicanto elects and for up to 360 days, the sole remedy for an event of default relating to certain failures by Corsicanto or the Company, as the case may be, to comply with certain reporting covenants in the Indenture consists exclusively of the right to receive additional interest on the 2014 Notes. Additional covenants pertaining to the 2012 Notes (as described above for the January 2012 Exchangeable Senior Notes) are also applicable to the May 2014 Notes.

As a result of the note exchange (as described above), the Company assessed both quantitative and qualitative aspects of the features of the 2014 Notes as compared to the 2012 Notes. Such assessment resulted in the conclusion that the features of the 2014 Notes represent a substantive modification from the 2012 Notes as the terms of the exchange resulted in a substantive modification to the embedded conversion feature within the 2012 Notes, and as such should be accounted for as an extinguishment of debt. In accordance with ASC 470-20, the Company extinguished the 2012 Notes by recording a gain on extinguishment of the liability component of $38.0 million and repurchase of the conversion option in equity through a reduction to additional paid-in capital of $10.1 million. The 2014 Notes were recorded at fair value of $90.8 million representing a $27.9 million discount to par. In addition the Company recognized $2.5 million in underwriter’s fees and offering costs and recognized those costs as deferred assets. The Company further allocated $3.5 million of the $90.8 million fair value of the 2014 Notes to the derivative liability related to the fundamental change redemption feature (as described above), which will be measured at fair value on an ongoing basis. During the nine months ended September 30, 2015, the Company recognized a $0.8 million gain on the change in fair value of the redemption feature. The fair value of this derivative liability is remeasured at each reporting period, with changes in fair value recognized in the statement of operations and any changes in the assumptions used in measuring the fair value of the derivative liability could result in a material increase or decrease in its carrying value.

Because the conversion option in the 2014 Notes receives an exception from derivative accounting and only requires gross physical settlement in shares, the embedded option does not require separate accounting and is therefore accounted for as part of the debt host at amortized cost. The debt discount is being amortized as interest expense over the estimated life of the 2014 Notes and recognized in the statement of operations as interest expense. As of September 30, 2015 and December 31, 2014, the carrying value of the 2014 Notes, net of the unamortized debt discount, was $94.8 million and $90.6 million, respectively. During the nine months ended September 30, 2015, the Company recognized aggregate interest expense of $8.5 million related to the Notes, of which $4.6 million represents amortization of the debt discount and $3.9 million represents contractual coupon interest. During the nine months ended September 30, 2014, the Company recognized aggregate interest expense of $6.7 million related to the Notes, of which $2.8 million represents non-cash interest and $3.9 million represents contractual coupon interest.

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As of September 30, 2015 and December 31, 2014, the Company had accrued interest on the Notes of $1.1 million and $2.4 million, respectively, which is included in other current liabilities. The Company made the contractual interest payments due on the Notes during the nine months ended September 30, 2015 and 2014 of $5.3 million.

Litigation

In the ordinary course of business, the Company is from time to time involved in lawsuits, claims, investigations, proceedings, and threats of litigation relating to its business. “Item 3. Legal Proceedings” of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014 includes a discussion of the Company’s current legal proceedings. There have been no material changes to those disclosures as of the date of this filing other than as set forth below.

On May 7, 2015, the Company and a group of independent physicians filed a federal lawsuit to permit the Company to share truthful and non-misleading information, including, but not limited to, the ANCHOR trial clinical data, with healthcare professionals in the United States about certain uses of Vascepa not included with approved FDA labeling of Vascepa and thus not permitted under the FDA’s interpretation of applicable law. The lawsuit, captioned Amarin Pharma, Inc., et al. v. Food & Drug Administration, et al. (1:15-cv-03588-PAE), was filed in the United States District Court for the Southern District of New York and seeks a judicial declaration based on several legal theories. On August 7, 2015, the Court granted the Company’s request for preliminary relief in this litigation through a declaratory judgment that confirmed the Company may engage in truthful and non-misleading speech with healthcare professionals promoting the off-label use of Vascepa, i.e., to treat patients with persistently high triglycerides, and such speech may not form the basis of a misbranding action under the Federal Food and Drug Cosmetic Act. FDA did not appeal the Court’s preliminary ruling prior to the October 6, 2015 deadline for appeal. The underlying litigation has been stayed for settlement discussion and the parties are working toward settlement. The Company cannot predict the outcome of settlement negotiations or this litigation.

On May 28, 2015, the U.S. District Court for the District of Columbia granted the Company’s motion for summary judgment in the Company’s lawsuit against the FDA, captioned Amarin Pharmaceuticals Ireland Ltd. v. Food & Drug Administration, et al., Civ. A. No. 14-0324 (D.D.C.). This lawsuit sought an order requiring FDA to recognize five-year, New Chemical Entity (“NCE”) marketing exclusivity for Vascepa. The decision vacated the FDA’s denial of the Company’s claim for such exclusivity and remanded to the FDA for proceedings consistent with the decision. On July 22, 2015, Watson Laboratories Inc., the purported first Vascepa ANDA filer, sought to intervene and appeal the Court’s decision. The Company intends to continue to litigate the case vigorously, but cannot predict the outcome of this litigation. FDA did not appeal the Court’s decision prior to the July 28, 2015 deadline for appeal.

Based on the May 28, 2015 U.S. District Court for the District of Columbia order granting the Company’s motion for summary judgment in the NCE litigation, on June 26, 2015, the parties to the related Vascepa patent litigation that followed acceptance by FDA of abbreviated new drug applications, or ANDAs, to Vascepa agreed to a full stay of proceeding in that patent litigation. Based on subsequent FDA notification to the ANDA filers that FDA had changed the status of their ANDAs to submitted, but no longer accepted, the Company believes the statutory basis for the patent litigation (accepted ANDAs) no longer exists. Thus, on July 24, 2015, the Company moved to dismiss the pending patent infringement lawsuits against each of the Vascepa ANDA applicants. The Company cannot predict the outcome of this motion to dismiss or litigation. If the motion to dismiss is granted, the Company plans to defend the exclusivity of Vascepa through patent litigation after notification that FDA has accepted an ANDA application related to Vascepa which, assuming NCE exclusivity, the Company would expect no sooner than late July 2016.

On June 29, 2015, the U.S. District Court for the District of New Jersey granted the Company’s motion to dismiss the putative consolidated class action lawsuit captioned In re Amarin Corporation plc, Securities Litigation, No. 3:13-cv-06663 (D.N.J. Nov. 1, 2013). The class action was dismissed without prejudice with leave for plaintiffs to file an amended complaint. The lawsuit sought unspecified monetary damages and attorneys’ fees and costs alleging that Amarin and certain of its current and former officers and directors made misstatements and omissions regarding the FDA’s willingness to approve Vascepa’s ANCHOR indication and related contributing factors and the potential relevance of data from the ongoing REDUCE-IT trial to that potential approval. On July 29, 2015, plaintiffs filed an amended complaint alleging facts similar to those in the original complaint. Like the first complaint, the amended complaint seeks unspecified monetary damages and attorneys’ fees and costs. The Company believes it has valid defenses and will continue to vigorously defend against this lawsuit, but cannot predict the outcome. The Company has insurance coverage that is anticipated to cover any significant loss exposure that may arise from this action.

Milestone and Supply Purchase Obligations

The Company entered into several product development agreements with, subject to performance obligations, certain milestone and supply purchase obligations.

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The Company entered into long-term supply agreements with multiple FDA-approved API suppliers and encapsulators. Certain supply agreements require annual minimum volume commitments by the Company and certain volume shortfalls may require payments for such shortfalls. The Company continues to meet its contractual volume obligations.

Under the 2004 share repurchase agreement with Laxdale Limited, or Laxdale, upon receipt of marketing approval in Europe for the first indication for Vascepa (or first indication of any product containing Amarin Neuroscience intellectual property acquired from Laxdale in 2004), the Company must make an aggregate stock or cash payment to the former shareholders of Laxdale (at the sole option of each of the sellers) of £7.5 million (approximately $11.4 million as of September 30, 2015). Also under the Laxdale agreement, upon receipt of a marketing approval in the United States or Europe for a further indication of Vascepa (or further indication of any other product using Amarin Neuroscience intellectual property), the Company must make an aggregate stock or cash payment (at the sole option of each of the sellers) of £5 million (approximately $7.6 million as of September 30, 2015) for each of the two potential market approvals (i.e., £10 million maximum, or approximately $15.2 million as of September 30, 2015).

The Company has no provision for any of the obligations above since the amounts are either not probable or able to be estimated as of September 30, 2015.

Warrants

During the nine months ended September 30, 2015, the Company issued 1,844,585 shares upon the exercise of warrants, resulting in gross and net proceeds of $2.8 million and $2.7 million, respectively. During the nine months ended September 30, 2014, the Company issued 1,684,888 shares upon the exercise of warrants, resulting in gross and net proceeds of $1.7 million.

Incentive Equity Awards

As of September 30, 2015, there were an aggregate of 17,626,803 stock options and 11,001,361 restricted stock units (“RSUs”) outstanding, representing approximately 7% and 4%, respectively, of outstanding shares (including common and preferred shares) on a fully diluted basis.

During the nine months ended September 30, 2015 and 2014, the Company issued 18,020 and 234,500 shares, respectively, as a result of the exercise of stock options, resulting in gross and net proceeds of $31 thousand and $0.3 million, respectively, for each period.

On July 6, 2015, the Company granted a total of 1,455,000 RSUs and 5,470,000 stock options to employees under the Amarin Corporation plc Stock Incentive Plan (the “2011 Plan”). The RSUs granted vest over a four year period. Of the total stock options granted, 3,670,000 stock options vest over a four year period while the remaining 1,800,000 stock options vest upon the achievement of certain performance conditions. During the nine months ended September 30, 2015, the Company issued 84,688 common shares related to the vesting of these RSUs, of which 17,734 shares were retained as treasury shares as settlement of employee tax obligations.

Also on July 6, 2015, the Company granted a total of 413,500 RSUs and 288,657 stock options to members of the Company’s Board of Directors under the 2011 Plan. Of the total awards granted, 283,500 RSUs and 121,506 stock options vest in equal installments over a three year period upon the earlier of the one-year anniversary of the grant date or the Company’s annual general meeting of shareholders in such anniversary year, while the remaining 130,000 RSUs and 167,151 stock options vest in full upon the earlier of the one-year anniversary of the grant date or the Company’s annual general meeting of shareholders in such anniversary year. Upon termination of service to the Company or upon a change of control, each Director shall be entitled to a payment equal to the fair market value of one share of Amarin common stock, which is required to be made in shares.

On January 29, 2015, the Company granted a total of 2,564,251 RSUs and 1,622,500 stock options to employees under the 2011 Plan. The RSUs vest annually over a three year period and the stock options vest over a four year period. Also on January 29, 2015, the Company granted 5,455,500 RSUs to employees under the 2011 Plan that vest upon the achievement of certain performance conditions. The issuance of these performance RSUs was contingent upon shareholder approval to increase the aggregate number of shares authorized for issuance under the 2011 Plan, which was obtained at the Company’s Annual General Meeting of Shareholders held on July 6, 2015.

On March 11, 2014, the Company granted a total of 173,348 RSUs and 205,890 stock options to members of the Company’s Board of Directors under the 2011 Plan. Upon termination of service to the Company or upon a change of control, each Director shall be entitled to a payment equal to the fair market value of one share of Amarin common stock, which is required to be made in shares. The RSUs vest in equal installments over a three year period upon the earlier of the anniversary of the grant date or the Company’s annual general meeting of shareholders in such anniversary year. The stock options vest in full upon the earlier of the anniversary of the grant date or the Company’s annual general meeting of shareholders in such anniversary year.

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On January 8, 2014, the Company granted a total of 2,082,000 RSUs and 2,605,500 stock options to employees under the 2011 Plan. The RSUs vest annually over a three year period and the stock options vest monthly over a four year period. During the nine months ended September 30, 2015, the Company issued 639,500 common shares related to the vesting of these RSUs, of which 114,258 shares were retained as treasury shares as settlement of employee tax obligations.

During the three months ended September 30, 2014, the Company received a refund of $3.2 million for UK stamp duty taxes paid in prior periods related to the issuance of common stock. Such proceeds were recorded as an increase to additional paid-in capital.

Preferred Stock

On March 5, 2015, the Company entered into a subscription agreement with four institutional investors (the “Purchasers”), including both existing and new investors, for the private placement of 352,150,790 restricted American Depositary Shares, each representing one (1) share of Amarin’s Series A Convertible Preference Shares, par value £0.05 per share, in the capital of the Company (“Series A Preference Shares”), resulting in gross proceeds to the Company of $52.8 million. The closing of the private placement occurred on March 30, 2015.

For each restricted American Depositary Share, the Purchasers paid a negotiated price of $0.15 (equating to $1.50 on an as-converted to ordinary share basis), resulting in $52.8 million in aggregate gross proceeds to the Company, before deducting estimated offering expenses of approximately $0.7 million. The net proceeds are reflected as preferred stock in the accompanying condensed consolidated balance sheets.

Each ten (10) Series A Preference Shares may be consolidated and redesignated as one (1) ordinary share, par value £0.50 per share, in the capital of the Company, each ordinary share to be represented by American Depositary Shares (“ADSs”), provided that consolidation will be prohibited if, as a result, the holder of such Series A Preference Shares and its affiliates would beneficially own more than 4.99% of the total number of Amarin ordinary shares or ADSs outstanding following such redesignation (the “Beneficial Ownership Limitation”). By written notice to the Company, a holder may from time to time increase or decrease the Beneficial Ownership Limitation to any other percentage not in excess of 19.9% specified in such notice; provided that any such increase will not be effective until the sixty-first (61st) day after such notice is delivered to the Company. This consolidation and redesignation may be effected by a holder of Series A Preference Shares following the first to occur of the resale of the ADSs representing the ordinary shares being registered for resale under the Securities Act pursuant to an effective registration statement, following any sale of the ADSs representing the ordinary shares pursuant to Rule 144 under the Securities Act, or if such ADSs representing the ordinary shares are eligible for sale under Rule 144, following the expiration of the one-year holding requirement under Rule 144. During the nine months ended September 30, 2015, at the request of the holders, a portion of the Series A Preference Shares were consolidated and redesignated, resulting in the issuance of 6,283,333 ADSs such that a maximum of 32,818,464 ordinary shares remain issuable upon future consolidation and redesignation of the remaining Series A Preference Shares, inclusive of the shares issued in July 2015 as discussed below, subject to certain adjustments for dilutive events.

Except as otherwise provided in the Series A Preference Share Terms or as required by applicable law, the Series A Preference Shares have no voting rights. However, as long as any Series A Preference Shares are outstanding, the Company cannot, without the approval of the holders of seventy-five percent (75%) of the then outstanding Series A Preference Shares, alter or change adversely the powers, preferences or rights attaching to the Series A Preference Shares or enter into any agreement with respect to the foregoing.

Holders of the Series A Preference Shares are entitled to receive, and the Company is required to pay, dividends (other than dividends in the form of ordinary shares) on the Series A Preference Shares equal (on an as-if-converted-to-ordinary-shares basis) to and in the same form as dividends (other than dividends in the form of ordinary shares) actually paid on ordinary shares when, as and if such dividends (other than dividends in the form of ordinary shares) are paid on the ordinary shares.

The restricted American Depositary Shares and Series A Preference Shares have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), or state securities laws and may not be offered or sold in the United States absent registration with the Securities and Exchange Commission (SEC) or an applicable exemption from registration requirements. The Company filed a registration statement with the SEC covering the resale of the restricted American Depositary Shares and the ADSs representing ordinary shares created by the consolidation and redesignation of the Series A Preference Shares (the “Registrable Securities”) on April 9, 2015. In addition, the Company agreed to use its commercially reasonable best efforts to effect and to keep the registration, and any qualification, exemption or compliance under state securities laws which the Company determines to obtain, continuously effective, and to keep the Registration Statement free of any material misstatements or omissions, until the earlier of (a) March 11, 2017 or (b) the date on which all Registrable Securities held by Purchasers may be sold or transferred in compliance with Rule 144 under the Securities Act, without any volume or manner of sale restrictions.

The Series A Preference Shares contain a contingent beneficial conversion feature (BCF) because they contain a conversion feature at a fixed rate that was in-the-money when issued. The BCF was recorded in the three months ended June 30, 2015 as a result of the related Form S-3 Registration Statement being declared effective, which represents the resolution of the contingency to convert the Series A Preference Shares. The BCF was recognized in stockholders’ deficit and was measured by allocating a portion of the

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proceeds equal to the intrinsic value of that feature to additional paid-in capital. The effective purchase price of the ordinary shares into which the preferred shares are convertible was $1.50, which was used to compute the intrinsic value. The intrinsic value was calculated as the difference between the effective purchase price of the ordinary shares and the market value ($2.39 per share) on the date the preferred shares were issued, multiplied by the number of shares into which the preferred shares are convertible. The BCF resulting from the issuance of the Series A Preference Shares was determined to be $31.3 million. The BCF was recorded as a non-cash dividend to preferred shareholders through accumulated deficit, and is therefore reflected as an adjustment to net loss applicable to common shareholders for earnings per common share purposes in accordance with GAAP.

On March 30, 2015, in connection with the closing of the private placement, and pursuant to a pre-existing contractual right to participate in certain private placement transactions effected by the Company, the Company entered into a separate subscription agreement with an existing investor, Sofinnova Venture Partners VII L.P. (Sofinnova), for the purchase of an additional $5.8 million of restricted American Depositary Shares, each representing one (1) share of the Company’s Series A Preference Shares, at the same price per share and otherwise on substantially the same terms as the initial private placement (the “Second Private Placement”). In accordance with applicable marketplace rules of the NASDAQ Stock Market, the consummation of the Second Private Placement was conditioned upon approval by the Company’s shareholders at a future meeting of the Company’s shareholders. Such approval was received at the Company’s Annual General Meeting of Shareholders on July 6, 2015 and as a result, the closing of the Second Private Placement occurred on July 10, 2015. The Company issued 38,867,180 restricted ADSs, each representing one Series A Preference Share, which may be consolidated and redesignated from time to time up to a maximum of 3,886,718 ordinary shares, each ordinary share to be represented by one ADS. For each restricted ADS, Sofinnova paid a negotiated price of $0.15 (equating to $1.50 on an as converted to ordinary share basis) resulting in gross proceeds to the Company of $5.8 million. Dr. James Healy, a member of the Company’s Board, is a managing member of Sofinnova Management VII, L.L.C., the general partner of Sofinnova.

The existence of this preferred stock purchase option was determined to be a derivative liability effective March 5, 2015, the date in which the private placement was initially subscribed. The fair value of this liability was calculated using a Black-Scholes model and was determined to be $0.9 million at inception and was charged to accumulated deficit as a deemed non-cash dividend to Sofinnova. The liability was then marked to fair value as of March 30, 2015, the date on which the Company executed a subscription agreement with Sofinnova, resulting in a charge of $0.9 million through (loss) gain on change in fair value of derivatives. The liability of $1.8 million was reclassified to permanent equity (additional paid-in capital) on such date. Subsequent to approval of the Second Private Placement, the Company recorded the remaining value of the BCF related to this share issuance as a non-cash dividend to preferred shareholders through accumulated deficit. The value of the BCF was determined on the same basis as the first private placement and amounted to $3.4 million less $1.8 million previously recorded for the preferred stock purchase option for a net non-cash charge of $1.6 million.

On March 31, 2014, the Company entered into a Co-Promotion Agreement (the Agreement) with Kowa Pharmaceuticals America, Inc. related to the commercialization of Vascepa^® (icosapent ethyl) capsules in the United States. Under the terms of the Agreement, Amarin granted to Kowa Pharmaceuticals America, Inc. the right to be the sole co-promoter, together with the Company, of Vascepa in the United States during the term. The initial term of the Agreement extends through 2018.

During the term, Kowa Pharmaceuticals America, Inc. and Amarin have agreed to use commercially reasonable efforts to promote, detail and optimize sales of Vascepa in the United States. The performance requirements include a negotiated minimum number of details to be delivered by each party in the first and second position, and the use of a negotiated number of minimum sales representatives from each party, including no less than 250 Kowa Pharmaceuticals America, Inc. sales representatives. Kowa Pharmaceuticals America, Inc. has agreed to continue to bear the costs incurred for its sales force associated with the commercialization of Vascepa and to pay for certain incremental costs associated with the use of its sales force, such as sample costs and costs for promotional and marketing materials. Amarin will continue to recognize all revenue from sales of Vascepa and will use commercially reasonable efforts to maintain a minimum amount of inventory of Vascepa for use in the United States.

In exchange for Kowa Pharmaceuticals America, Inc.’s co-promotional services, Kowa Pharmaceuticals America, Inc. is entitled to a quarterly co-promotion fee based on a percentage of Vascepa gross margin that increases during the Agreement’s term, from the high single digits in 2014 to the low twenty percent level in 2018. The co-promotion fee also varies based on sales levels and whether the FDA has approved an ANCHOR indication labeling expansion for Vascepa or has permitted the use of data generated to support obtaining FDA approval of the ANCHOR indication in the promotion of Vascepa, in which case the co-promotion fee would be decreased if specified requirements are met. In certain circumstances, upon the earlier of the expiration or termination of the Agreement in accordance with its terms, Kowa Pharmaceuticals America, Inc. may be eligible for a co-promotion tail fee equal to declining fractions of the co-promote fee in effect prior to such expiration or termination for periods ranging from one to three years following such expiration or termination.

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As of September 30, 2015 and December 31, 2014, the Company had a net payable of $0.4 million and a net receivable of $0.6 million, respectively, from Kowa Pharmaceuticals America, Inc. representing co-promotion fees payable to Kowa Pharmaceuticals America, Inc. net of reimbursable amounts incurred for samples and other marketing expenses.

On February 26, 2015, the Company entered into a Development, Commercialization and Supply Agreement (the “DCS Agreement”) with Eddingpharm (Asia) Macao Commercial Offshore Limited (“Eddingpharm”) related to the development and commercialization of Vascepa in Mainland China, Hong Kong, Macau and Taiwan (the “China Territory”). Under the terms of the DCS Agreement, the Company granted to Eddingpharm an exclusive (including as to the Company) license with right to sublicense to develop and commercialize Vascepa in the China Territory for uses that are currently commercialized and under development by the Company based on the Company’s MARINE, ANCHOR and ongoing REDUCE-IT clinical trials of Vascepa.

Under the DCS Agreement, Eddingpharm will be solely responsible for development and commercialization activities in the China Territory and associated expenses. The Company will provide development assistance and be responsible for supplying finished and later bulk drug product at defined prices under negotiated supply terms. The Company will retain all Vascepa manufacturing rights. Eddingpharm has agreed to certain restrictions regarding the commercialization of competitive products globally and the Company has agreed to certain restrictions regarding the commercialization of competitive products in the China Territory.

The Company and Eddingpharm agreed to form a joint development committee to oversee regulatory and development activities for Vascepa in the China Territory in accordance with a negotiated development plan and to form a separate joint commercialization committee to oversee Vascepa commercialization activities in the China Territory. Development costs will be paid by Eddingpharm to the extent such costs are incurred in connection with the negotiated development plan or otherwise incurred by Eddingpharm. Eddingpharm will be responsible for preparing and filing regulatory applications in all countries of the China Territory at Eddingpharm’s cost with the Company’s assistance. The DCS Agreement also contains customary provisions regarding indemnification, packaging, record keeping, audit rights, reporting obligations, and representations and warranties that are customary for an arrangement of this type.

The term of the DCS Agreement expires, on a product-by-product basis, upon the later of (i) the date on which such product is no longer covered by a valid claim under a licensed patent in the China Territory, or (ii) the twelfth (12th) anniversary of the first commercial sale of such product in Mainland China. The DCS Agreement may be terminated by either party in the event of a bankruptcy of the other party and for material breach, subject to customary cure periods. In addition, at any time following the third anniversary of the first commercial sale of a product in Mainland China, Eddingpharm has the right to terminate the DCS Agreement for convenience with twelve months’ prior notice. Neither party may assign or transfer the DCS Agreement without the prior consent of the other party, provided that the Company may assign the DCS Agreement in the event of a change of control transaction.

Upon closing of the DCS Agreement, the Company received a non-refundable $15.0 million up-front payment, which it will recognize as revenue over the estimated period in which the Company is required to provide initial and on-going regulatory and development support and clinical supply for obtaining regulatory approvals in the China Territory and through the estimated period in which the Company is required to provide commercial supply, which is currently estimated to be a period of approximately 16 years. Consequently, the Company recognized $0.5 million of the up-front payment as licensing revenue during the nine months ended September 30, 2015 and recorded $14.5 million as deferred revenue as of September 30, 2015. In addition to the non-refundable, up-front payment, the Company is entitled to receive development, regulatory and sales-based milestone payments of up to an additional $154.0 million as well as tiered double-digit percentage royalties on net sales of Vascepa in the China Territory escalating to the high teens. Revenues relating to these milestone payments and royalties will be recognized upon satisfaction of the applicable performance obligations or over the period in which such performance obligations are completed, as applicable.

The Company has evaluated subsequent events from September 30, 2015 through the date of the issuance of these condensed consolidated financial statements.

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This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. These forward-looking statements reflect our plans, estimates and beliefs. These statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “anticipates,” “believes,” “could,” “estimates,” “expects,” “intends,” “may,” “plans,” “potential,” “predicts,” “projects,” “should,” “would” and similar expressions intended to identify forward-looking statements. Forward-looking statements reflect our current views with respect to future events and are based on assumptions and subject to risks and uncertainties. Because of these risks and uncertainties, the forward-looking events and circumstances discussed in this report may not transpire. We discuss many of these risks in Part I, Item 1A under the heading “Risk Factors” of our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 and below under Part II, Item IA, “Risk Factors”.

Given these uncertainties, you should not place undue reliance on these forward-looking statements. Also, forward-looking statements represent our estimates and assumptions only as of the date of this document. You should read this document with the understanding that our actual future results may be materially different from what we expect. Except as required by law, we do not undertake any obligation to publicly update or revise any forward-looking statements contained in this report, whether as a result of new information, future events or otherwise.

Overview

We are a biopharmaceutical company with expertise in lipid science focused on the commercialization and development of therapeutics to improve cardiovascular health.

Our lead product, Vascepa^® (icosapent ethyl) capsules, is approved by the U.S. Food and Drug Administration, or FDA, for use as an adjunct to diet to reduce triglyceride levels in adult patients with severe (TG ³500 mg/dL) hypertriglyceridemia. Vascepa is available in the United States by prescription only. We began selling and marketing Vascepa in the United States in January 2013. In August 2015, we also began marketing Vascepa in the United States for the treatment of patients with high (TG ³200 mg/dL and <500 mg/dL) triglyceride levels who are also on statin therapy for elevated low-density lipoprotein cholesterol, or LDL-C, levels which we refer to as mixed dyslipidemia. We sell Vascepa principally to a limited number of major wholesalers, as well as selected regional wholesalers and specialty pharmacy providers, or collectively, its Distributors, that in turn resell Vascepa to retail pharmacies for subsequent resale to patients and health care providers. We market Vascepa through our sales force of approximately 150 sales professionals, including sales representatives and their managers. In March 2014, we entered into a co-promotion agreement with Kowa Pharmaceuticals America, Inc. under which approximately 250 Kowa Pharmaceuticals America, Inc. sales representatives began to devote a substantial portion of their time to promoting Vascepa starting in May 2014.

In February 2015, we announced an exclusive agreement with Eddingpharm (Asia) Macao Commercial Offshore Limited, or Eddingpharm, to develop and commercialize Vascepa capsules in Mainland China, Hong Kong, Macau and Taiwan (the “China Territory”). We are also assessing other partnership opportunities for licensing Vascepa in other territories outside of the United States.

Triglycerides are fats in the blood. Hypertriglyceridemia refers to a condition in which patients have high levels of triglycerides in the bloodstream. It is estimated that over 70 million adults in the United States have elevated triglyceride levels (TG >150 mg/dL), approximately 40 million adults in the United States have high triglyceride levels (TG >200 mg/dL), and approximately 4.0 million people in the United States have severely high triglyceride levels (TG >500 mg/dL), commonly known as very high triglyceride levels. Many patients with high triglycerides also have other lipid level abnormalities such as high cholesterol. The patient condition of having more than one lipid level abnormality is referred to as mixed dyslipidemia. According to The American Heart Association Scientific Statement on Triglycerides and Cardiovascular Disease (2011), triglycerides provide important information as a marker associated with the risk for heart disease and stroke, especially when an individual also has low high-density lipoprotein cholesterol, or HDL-C (often referred to as “good” cholesterol), and elevated levels of LDL-C (often referred to as “bad” cholesterol). Guidelines for the management of very high triglyceride levels suggest that reducing triglyceride levels is the primary goal in patients to reduce the risk of acute pancreatitis. The effect of Vascepa on cardiovascular mortality and morbidity, or the risk for pancreatitis, in patients with hypertriglyceridemia has not been determined.

We are currently focused on completing the ongoing REDUCE-IT (Reduction of Cardiovascular Events with EPA—Intervention Trial) cardiovascular outcomes study of Vascepa, which we started in December 2011. REDUCE-IT, a multinational, prospective, randomized, double-blind, placebo-controlled study, is the first prospective cardiovascular outcomes study of any drug in a population of patients who, despite stable statin therapy, have elevated triglyceride levels. Based on the results of REDUCE-IT, we plan to seek additional indicated uses for Vascepa. In REDUCE-IT, cardiovascular event rates for patients on stable statin therapy plus

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four grams per day of Vascepa will be compared to cardiovascular event rates for patients on stable statin therapy plus placebo. The REDUCE-IT study is designed to be completed after reaching an aggregate number of cardiovascular events. Based on projected event rates, we estimate the REDUCE-IT study can be completed in or about 2017 with results then expected to be available and published in 2018. An interim review of the efficacy and safety results of the trial is scheduled to occur upon reaching 60% of the target aggregate number of cardiovascular events. We currently expect this interim review by the independent data monitoring committee (DMC) to occur during 2016 and it is our expectation that the trial will run to completion. The DMC has been more frequently examining interim reviews of the safety data from the study. Following each of these reviews, the DMC has communicated to us that we should continue the study as planned. We remain blinded to all data from the study. Over 97% of the 8,000 patients targeted for enrollment in the REDUCE-IT study have been enrolled.

The potential efficacy and safety of Vascepa (known in its development stage as AMR 101) has been studied in two Phase 3 clinical trials, the MARINE trial and the ANCHOR trial. At a daily dose of 4 grams of Vascepa, the dose at which Vascepa is FDA approved, these trials showed favorable clinical results in their respective patient populations in reducing triglyceride levels without increasing LDL-C levels in the MARINE trial and with a statistically significant decrease in LDL-C levels in the ANCHOR trial, in each case, relative to placebo. These trials also showed favorable results, particularly with the 4-gram dose of Vascepa, in other important lipid and inflammation biomarkers, including apolipoprotein B (apo B), non-high-density lipoprotein cholesterol (non-HDL-C), total-cholesterol (TC), very low-density lipoprotein cholesterol (VLDL-C), lipoprotein-associated phospholipase A2 (Lp-PLA2), and high sensitivity C-reactive protein (hs-CRP). In these trials, the most commonly reported adverse reaction (incidence >2% and greater than placebo) in Vascepa-treated patients was arthralgia (joint pain) (2.3% for Vascepa vs. 1.0% for placebo).

We also developed Vascepa for FDA approval for the treatment of patients with high (TG ³200 mg/dL and <500 mg/dL) triglyceride levels who are also on statin therapy for elevated low-density lipoprotein cholesterol, or LDL-C, levels which we refer to as mixed dyslipidemia. We refer to this second proposed indication for Vascepa as the ANCHOR indication.

On October 16, 2013, the FDA convened an advisory committee to review our supplemental new drug application, or sNDA, seeking marketing approval of Vascepa for use in the ANCHOR indication. This advisory committee was not asked by the FDA to evaluate whether Vascepa is effective in lowering triglycerides in the studied population, the ANCHOR indication as specified in the sNDA. Rather, the advisory panel was asked whether Vascepa would improve cardiovascular outcomes or whether approval of the ANCHOR indication should wait for successful completion of the REDUCE-IT study. The advisory committee voted 9 to 2 against recommending approval of the ANCHOR indication based on information presented at the meeting.

The ANCHOR clinical study was conducted under a special protocol assessment, or SPA, agreement with the FDA. On October 29, 2013, the FDA rescinded the ANCHOR study SPA agreement because the FDA determined that a substantial scientific issue essential to determining the effectiveness of Vascepa in the studied population was identified after testing began. On April 27, 2015, following three attempts by us to appeal the SPA agreement rescission decision by the FDA, we received a Complete Response Letter, or CRL, from the FDA regarding our ANCHOR sNDA. In the CRL, the FDA acknowledged that Vascepa yielded a treatment difference showing reduced triglyceride levels compared to placebo in patients treated in the ANCHOR study. The FDA concluded that, for regulatory approval purposes, there are insufficient data at this time to support a drug-induced change in serum triglycerides as a surrogate for reducing cardiovascular risk in the ANCHOR population. The FDA views the ANCHOR indication as ostensibly and impliedly an indication to reduce cardiovascular risk. The FDA did not determine that the drug-induced effects of Vascepa, which go beyond triglyceride-lowering, would not actually reduce cardiovascular risk in this population. We had proposed to the FDA multiple alternative indications, data presentations, disclaimers and other regulatory pathways to approval under the ANCHOR sNDA, but the FDA determined not to approve label expansion reflecting the ANCHOR clinical trial efficacy data at this time. Safety data from the ANCHOR study remain in the currently approved label for Vascepa. Vascepa remains FDA approved for use as an adjunct to diet to reduce triglyceride levels in adult patients with severe hypertriglyceridemia, and current Vascepa labeling remains unchanged. The CRL has no effect on the SPA agreement for the REDUCE-IT study or the anticipated timing for results from the REDUCE-IT study. Based on our communications with the FDA, we expect that final positive results from the REDUCE-IT outcomes study will be required for label expansion for Vascepa.

On May 7, 2015, we and a group of independent physicians filed a lawsuit in federal court to permit us to promote to healthcare professionals the use of Vascepa in patients with mixed dyslipidemia so long as the promotion is truthful and non-misleading. This use reflects recognized medical practice but is not covered by current FDA-approved labeling for the drug and is thus considered by FDA to be illegal off-label promotion. On August 7, 2015, we were granted preliminary relief in the form of a declaratory judgment in this lawsuit. The court declaration permits us to promote to healthcare professionals the FDA-reviewed and agreed effects of Vascepa demonstrated in the ANCHOR clinical trial and presentation of the current state of scientific research related to the potential of Vascepa to reduce the risk of cardiovascular disease including through use of peer-reviewed scientific publications of available data. The FDA did not appeal the court’s ruling prior to the October 6, 2015 deadline. The underlying litigation has been stayed for settlement discussion and the parties are working toward settlement.

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Commercialization – United States

We commenced the commercial launch of Vascepa in the United States in January 2013. We commenced sales and shipments of Vascepa at that time to our network of U.S.-based wholesalers. We now market Vascepa in the United States through our sales force of approximately 150 sales professionals and their managers. Commencing in May 2014, in addition to promotion by our sales representatives, approximately 250 Kowa Pharmaceuticals America, Inc. sales representatives began promoting Vascepa. We also employ various marketing personnel to support our commercialization of Vascepa.

Under our co-promotion agreement with Kowa Pharmaceuticals America, Inc., both parties have agreed to use commercially reasonable efforts to promote, detail and optimize sales of Vascepa in the United States and have agreed to specific performance requirements detailed in the related agreement. The performance requirements include a negotiated minimum number of sales details to be delivered by each party in the first and second position, the use of a negotiated number of minimum sales representatives from each party, including no less than 250 Kowa Pharmaceuticals America, Inc. sales representatives and the achievement of minimal levels of Vascepa revenue in 2015 and beyond. Kowa Pharmaceuticals America, Inc. has also agreed to continue to bear the costs incurred for its sales force associated with the commercialization of Vascepa and to pay for certain incremental costs associated with the use of its sales force, such as sample costs and costs for promotional and marketing materials. We will continue to recognize all revenue from sales of Vascepa. In exchange for Kowa Pharmaceuticals America, Inc.’s co-promotional services, Kowa Pharmaceuticals America, Inc. is entitled to a quarterly co-promotion fee based on a percentage of aggregate Vascepa gross margins that increases during the term. The percentage of aggregate Vascepa gross margins earned by Kowa Pharmaceuticals America, Inc. is scheduled to increase from the high single digits in 2014, to fifteen percent (15%) in 2015, and to the low twenty percent levels in 2018, subject to certain adjustments. The term of this co-promotion agreement expires on December 31, 2018.

Based on monthly compilations of data provided by a third party, Symphony Health Solutions, the estimated number of normalized total Vascepa prescriptions for the three months ended September 30, 2015 was approximately 199,000 compared to 176,000, 154,000, and 132,000 in the three months ended June 30, 2015, March 31, 2015, and September 30, 2014, respectively. According to data from another third party, IMS Health, the estimated number of normalized total Vascepa prescriptions for the three months ended September 30, 2015 was approximately 176,000 compared to 157,000, 137,000, and 113,000 in the three months ended June 30, 2015, March 31, 2015, and September 30, 2014, respectively. Normalized total prescriptions represent the estimated total number of Vascepa prescriptions shipped to patients, calculated on a normalized basis (i.e., total capsules shipped divided by 120 capsules, or one month’s supply). The data reported above is based on information made available to us from third party resources and may be subject to adjustment and may overstate or understate actual prescriptions. Timing of shipments to wholesalers, as used for revenue recognition purposes, and timing of prescriptions as estimated by these third parties may differ from period to period. Although we believe these data are prepared on a period-to-period basis in a manner that is generally consistent and that such results are generally indicative of current prescription trends, these data are based on estimates and should not be relied upon as definitive. While we expect to be able to grow Vascepa revenues over time, no such guidance should be inferred from the operating metrics described above. We also anticipate that such sales growth may be inconsistent from period to period. We believe that investors should view the above-referenced operating metrics with caution, as data for this limited period may not be representative of a trend consistent with the results presented or otherwise predictive of future results. Seasonal fluctuations in pharmaceutical sales, for example, may affect future prescription trends of Vascepa, as could changes in prescriber sentiment and other factors. We believe investors should consider our results over several quarters, or longer, before making an assessment about potential future performance.

The commercialization of a new pharmaceutical product is a complex undertaking, and our ability to effectively and profitably commercialize Vascepa will depend in part on our ability to generate market demand for Vascepa through education, marketing and sales activities, our ability to achieve market acceptance of Vascepa, our ability to generate product revenue and our ability to receive adequate levels of reimbursement from third-party payers. See “Risk Factors—Risks Related to the Commercialization and Development of Vascepa.”

In August 2015, we and our co-promotion partner began communicating ANCHOR clinical trial data to targeted healthcare professionals. Such qualified communications are being made pursuant to the August 7, 2015 federal district court declaration allowing truthful and non-misleading promotion of the FDA-reviewed and agreed effects of Vascepa demonstrated in the ANCHOR clinical trial and presentation of the current state of scientific research related to the potential of Vascepa to reduce the risk of cardiovascular disease including through use of peer-reviewed scientific publications of available data.

Commercialization – Outside the United States

In February 2015, we announced an exclusive agreement with Eddingpharm to develop and commercialize Vascepa capsules in the territories of Mainland China, Hong Kong, Macau and Taiwan (the “China Territory”) for uses that are currently commercialized and under development by us in the United States based on the MARINE, ANCHOR and ongoing REDUCE-IT clinical trials of Vascepa.

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Under the agreement, Eddingpharm is responsible for development and commercialization activities in the China Territory and associated expenses. We will provide development assistance and be responsible for supplying the product. Terms of the agreement include up-front and milestone payments to us of up to $169.0 million, including a non-refundable $15.0 million up-front payment received at closing, and development, regulatory and sales-based milestone payments of up to an additional $154.0 million. Eddingpharm will also pay us tiered double-digit percentage royalties on net sales of Vascepa in the China Territory escalating to the high teens. We will supply finished product to Eddingpharm under negotiated supply terms.

We continue to assess other partnership opportunities for licensing Vascepa in other territories outside of the United States.

Research and Development

REDUCE-IT is the first prospective cardiovascular outcomes study of any drug in a population of patients who, despite stable statin therapy, have elevated triglyceride levels. REDUCE-IT is a multinational, prospective, randomized, double-blind, placebo-controlled study designed to assess the cumulative effect on the rate of cardiovascular events for patients treated with Vascepa as an add-on to statin therapy compared to the corresponding rate of cardiovascular events for patients treated with placebo on top of statin therapy. Based on the results of REDUCE-IT, we may seek additional indications for Vascepa beyond the indications studied in the ANCHOR or MARINE trials.

REDUCE-IT is designed to enroll 8,000 patients, of which over 7,700 patients have been enrolled. We currently estimate that we will complete patient enrollment in this study near the end of 2015.

Completion of the REDUCE-IT study is designed to occur after reaching an aggregate number of cardiovascular events. Based on projected event rates, we estimate the REDUCE-IT study can be completed in or about 2017 with results then expected to be available in 2018. An interim review of the efficacy and safety results of the trial is scheduled to occur upon reaching 60% of the target aggregate number of cardiovascular events. We currently expect this interim review by the independent data monitoring committee, or DMC, to occur during 2016. As is typical, the statistical threshold for defining overwhelming efficacy on the primary endpoint at the interim analysis is considerably higher than the threshold for defining statistical significance at the end of the study and it is our expectation that the trial will run to completion. Amarin remains blinded to all data from the study. Unless overwhelming efficacy and safety is declared by the DMC at the interim look or the study is halted due to a patient safety concern, Amarin personnel will remain blinded to the efficacy and safety data from the REDUCE-IT study until the study is complete. The DMC has periodically reviewed unblinded safety data since initiation of the REDUCE-IT study in 2011 and, after each such meeting to date, has recommended that the study be continued as planned. The pre-specified interim review at 60% of the target aggregate number of cardiovascular events will involve a look by the DMC in closed session at all efficacy and safety data available from the REDUCE-IT study at that time. Interim looks by independent DMCs are common in large, long-term outcomes studies. By design, it is most common for cardiovascular outcomes studies not to be stopped upon an interim look.

Our scientific rationale for the REDUCE-IT study is supported by (i) epidemiological data that suggests elevated triglyceride levels correlate with increased cardiovascular disease risk, (ii) genetic data that suggests triglyceride and/or triglyceride-rich lipoproteins (as well as low-density lipoprotein cholesterol (LDL cholesterol), known as bad cholesterol) are independently in the causal pathway for cardiovascular disease and (iii) clinical data that suggest substantial triglyceride reduction in patients with elevated baseline triglyceride levels correlates with reduced cardiovascular risk. Our scientific rationale for the REDUCE-IT study is also supported by research on the putative cardioprotective effects of EPA as presented in scientific literature. It is possible that the effects of EPA may be due not to a single mode of action, such as triglyceride lowering, but rather to multiple mechanisms working together. Studies in the scientific literature explore potentially beneficial effects of EPA on multiple atherosclerosis processes, including endothelial function, oxidative stress, foam cell formation, inflammation/cytokines, plaque formation/progression, platelet aggregation, thrombus formation, and plaque rupture. The REDUCE-IT study is needed to determine the clinical benefit, if any, of EPA therapy in statin-treated patients with elevated triglyceride levels.

Commercial Supply

To date, all of our active pharmaceutical ingredient, or API, that has been utilized in product sold has been manufactured by two suppliers: Nisshin Pharma, Inc., or Nisshin, and Chemport, Inc., or Chemport. A significant portion of such API was purchased from Nisshin at a price that is higher than expected future average API costs. During 2015, we began purchasing API from a third supplier, Finorga SAS, or Novasep. The amount of supply we seek to purchase in future periods will depend on the level of growth of Vascepa revenues and minimum purchase commitments with certain suppliers.

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Financial Position

We believe that our cash and cash equivalents balance of $119.0 million as of September 30, 2015 is sufficient to fund our projected operations for at least the next twelve months. Included in our cash balance as of September 30, 2015 was a $15.0 million non-refundable, up-front payment we received upon the execution of our first ex-U.S. licensing agreement in China and surrounding territories and net proceeds of $57.7 million we received from the issuance and sale of our Series A Preference Shares.

Financial Operations Overview

Product Revenue, net. All of our product revenue is derived from product sales of Vascepa, net of allowances, discounts, incentives, rebates, chargebacks and returns. We sell product to a limited number of major wholesalers, as well as selected regional wholesalers and specialty pharmacy providers, or collectively, our Distributors, who resell the product to retail pharmacies for purposes of their reselling the product to fill patient prescriptions. We commenced our commercial launch in the United States in January 2013. In accordance with U.S. Generally Accepted Accounting Principles (“GAAP”), until we had the ability to reliably estimate returns of Vascepa from our Distributors, revenue was recognized based on the resale of Vascepa for the purposes of filling patient prescriptions, and not based on our sales to such Distributors. Beginning in January 2014, we concluded that we had developed sufficient history such that we can reliably estimate returns and as a result, began to recognize revenue based on sales to our Distributors. Through September 30, 2015, product returns were de minimis.

Licensing revenue. Licensing revenue currently consists of revenue attributable to the receipt of an up-front, non-refundable payment related to a Vascepa license agreement in China, which is being recognized over the estimated period in which we are required to provide regulatory and development support and clinical and commercial supply pursuant to the agreement, which is currently anticipated to be a period of approximately 16 years.

Cost of Goods Sold. Cost of goods sold includes the cost of API for Vascepa on which revenue was recognized during the period, as well as the associated costs for encapsulation, packaging, shipment, supply management, insurance and quality assurance. The cost of the API included in cost of goods sold reflects the average cost method of inventory valuation and relief. This average cost reflects the actual purchase price of Vascepa API.

Selling, General and Administrative Expense. Selling, general and administrative expense consists primarily of salaries and other related costs for personnel, including stock-based compensation expense, in our sales, marketing, executive, business development, finance and information technology functions and co-promotion fees payable to Kowa Pharmaceuticals America, Inc. Other costs primarily include facility costs and professional fees for accounting, consulting and legal services.

Research and Development Expense. Research and development expense consists primarily of fees paid to professional service providers in conjunction with independent monitoring of our clinical trials and acquiring and evaluating data in conjunction with our clinical trials, fees paid to independent researchers, costs of qualifying contract manufacturers, services expenses incurred in developing and testing products and product candidates, salaries and related expenses for personnel, including stock-based compensation expense, costs of materials, depreciation, rent, utilities and other facilities costs. In addition, research and development expenses include the cost to support current development efforts, including patent costs and milestone payments, as well as the cost to support regulatory and development activities related to our development and commercialization agreement with our international partner, Eddingpharm. We expense research and development costs as incurred. In addition, research and development costs include the costs of product supply we received from suppliers when such receipt is prior to regulatory approval of the supplier.

(Loss) Gain on Change in Fair Value of Derivative Liabilities. (Loss) gain on change in fair value of derivative liabilities is comprised of: (i) the change in fair value of the warrant derivative liability, (ii) the change in fair value of the derivative liability related to the change in control provision associated with the December 2012 financing with BioPharma Secured Debt Fund II Holdings Cayman LP, or BioPharma, (iii) the change in fair value of the derivative liability related to the change in control provision associated with the May 2014 exchangeable senior notes; and (iv) the change in fair value of the derivative liability related to the preferred stock purchase option.

Interest and Other (Expense) Income, Net. Interest expense consists of interest incurred under lease obligations, interest incurred under our 3.5% exchangeable notes and interest incurred under our December 2012 financing arrangement with BioPharma. Interest expense under our exchangeable notes includes the amortization of the conversion option related to our exchangeable debt, the amortization of the related debt discounts and debt obligation coupon interest. Interest expense under our BioPharma financing arrangement is calculated based on an estimated repayment schedule. Interest income consists of interest earned on our cash and cash equivalents. Other (expense) income, net, consists primarily of foreign exchange losses and gains.

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Critical Accounting Policies and Significant Judgments and Estimates

Our discussion and analysis of our financial condition and results of operations is based on our condensed consolidated financial statements and notes, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenue and expenses. On an ongoing basis, we evaluate our estimates and judgments, including those related to derivative financial liabilities. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. A summary of our significant accounting policies is contained in Note 2 to our condensed consolidated financial statements included elsewhere in this Quarterly Report on Form 10-Q. We believe the following critical accounting policies affect our more significant judgments and estimates used in the preparation of our condensed consolidated financial statements.

Revenue Recognition—We sell Vascepa principally to a limited number of Distributors, that in turn resell Vascepa to retail pharmacies that subsequently resell it to patients and health care providers. In accordance with GAAP, our revenue recognition policy requires that: (i) there is persuasive evidence that an arrangement exists between us and the Distributor, (ii) delivery has occurred, (iii) collectability is reasonably assured and (iv) the price is fixed or determinable.

We began recognizing revenue from the sale of Vascepa following our commercial launch in the United States in January 2013. Prior to 2013, we recognized no revenue from Vascepa sales. We sell Vascepa to Distributors. In accordance with GAAP, until we had the ability to reliably estimate returns of Vascepa from our Distributors, revenue was recognized based on the resale of Vascepa for the purposes of filling patient prescriptions, and not based on our sales to such Distributors. Beginning in January 2014, we concluded that we had developed sufficient history such that we can reliably estimate returns and as a result, began to recognize revenue based on sales to our Distributors. Consequently, we recognized revenues of $54.6 million and $37.7 million based on sales to Distributors during the nine months ended September 30, 2015 and 2014, respectively. Through September 30, 2015, product returns were de minimis.

We have written contracts with our Distributors, and delivery occurs when a Distributor receives Vascepa. We evaluate the creditworthiness of each of our Distributors to determine whether revenues can be recognized upon delivery, subject to satisfaction of the other requirements, or whether recognition is required to be delayed until receipt of payment. In order to conclude that the price is fixed or determinable, we must be able to (i) calculate our gross product revenues from the sales to Distributors and (ii) reasonably estimate our net product revenues. We calculate gross product revenues based on the wholesale acquisition cost that we charge our Distributors for Vascepa. We estimate our net product revenues by deducting from our gross product revenues (a) trade allowances, such as invoice discounts for prompt payment and distributor fees, (b) estimated government and private payor rebates, chargebacks and discounts, such as Medicaid reimbursements, (c) reserves for expected product returns and (d) estimated costs of incentives offered to certain indirect customers, including patients.

When evaluating multiple-element arrangements, we identify the deliverables included within the agreement and evaluate which deliverables represent separate units of accounting based on whether the delivered element has stand-alone value to the collaborator or if the arrangement includes a general right of return for delivered items. We may receive up-front, non-refundable payments when licensing our intellectual property in conjunction with research and development agreements. In determining the units of accounting, we evaluate whether the license has stand-alone value from the undelivered elements to the collaborative partner based on the consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination include the stage of development of the license delivered, research and development capabilities of the partner and the ability of partners to develop and commercialize Vascepa independently.

When we believe a license to our intellectual property does not have stand-alone value from the other deliverables to be provided in the arrangement, we generally recognize revenue attributable to the license over the contractual or estimated performance period. Any unrecognized portion of license revenue is classified within deferred revenue in the accompanying condensed consolidated balance sheets. When we believe a license to our intellectual property has stand-alone value, we recognize revenue attributed to the license upon delivery. The periods over which revenue is recognized is subject to estimates and may change over the course of the agreement. Such a change could have a material impact on the amount of revenue we record in future periods.

Derivative Financial Liabilities—Derivative financial liabilities are initially recorded at fair value. They are subsequently held at fair value, with gains and losses arising for changes in fair value recognized in the statement of operations. The fair value of derivative financial liabilities is determined using various valuation techniques. We use our judgment to select a variety of methods and make assumptions that are mainly based on market conditions existing at each balance sheet date. Fluctuations in the assumptions used in the valuation model would result in adjustments to the fair value of the derivative liabilities reflected on our balance sheet and, therefore, our statement of operations. If we issue shares to discharge the liability, the derivative financial liability is derecognized and common stock and additional paid-in capital are recognized on the issuance of those shares. For options and warrants treated as

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derivative financial liabilities, at settlement date the carrying value of the options and warrants are transferred to equity. The cash proceeds received from shareholders for additional shares are recorded in common stock and additional paid-in capital. We have recorded financial derivatives related to certain outstanding warrants (extinguished as of September 30, 2015), the change in control provision associated with our December 2012 debt financing and the change in control provision associated with our May 2014 exchangeable senior notes.

Inventory—Prior to July 26, 2012, when we received approval from the FDA to market and sell Vascepa in the United States for the MARINE indication, Vascepa was considered a product candidate under development. All supply of Vascepa purchased prior to July 26, 2012 was not capitalized and instead charged as a component of research and development expense in the period received. After Vascepa was approved, we began to capitalize inventory purchased from Nisshin, the API supplier approved in the NDA. Prior to April 2013, Nisshin was the only FDA-approved supplier of API for Vascepa. In 2013, the FDA qualified additional API suppliers to produce Vascepa with approval of our sNDAs covering Chemport, Slanmhor Pharmaceutical, Inc., or Slanmhor, in a consortium which included Novasep as the manufacturer for Slanmhor, and a fourth API supplier which we subsequently reached mutual agreement to terminate due to production challenges. All supply purchases from API suppliers prior to FDA approval of these API suppliers in 2013 were not capitalized and instead charged as a component of research and development expense in the period received. Subsequent to the approval of these suppliers, we capitalize API purchases from them. Until an API supplier is approved, all Vascepa API purchased from such supplier is included as a component of research and development expense. Upon sNDA approval of each additional supplier, we capitalize subsequent Vascepa API purchases from such supplier as inventory. We state inventories at the lower of cost or market value. Cost is determined based on actual cost using the average cost method. An allowance is established when management determines that certain inventories may not be saleable. If inventory cost exceeds expected market value due to obsolescence, damage or quantities in excess of expected demand, we will reduce the carrying value of such inventory to market value. We expense inventory identified for use as marketing samples when they are packaged. The average cost reflects the actual purchase price of Vascepa API. Additionally, the determination of the classification of our inventory requires the use of estimates in order to determine the portion of inventories anticipated to be utilized within twelve months of the balance sheet date.

Income Taxes—Deferred tax assets and liabilities are recognized for the future tax consequences of differences between the carrying amounts and tax bases of assets and liabilities and operating loss carryforwards and other attributes using enacted rates expected to be in effect when those differences reverse. Valuation allowances are provided against deferred tax assets that are not more likely than not to be realized.

We provide reserves for potential payments of tax to various tax authorities or do not recognize tax benefits related to uncertain tax positions and other issues. Tax benefits for uncertain tax positions are based on a determination of whether a tax benefit taken by us in our tax filings or positions is more likely than not to be realized, assuming that the matter in question will be decided based on its technical merits. Our policy is to record interest and penalties in the provision for income taxes.

We assess our ability to realize deferred tax assets at each reporting period. The realization of deferred tax assets depends on generating future taxable income during the periods in which the tax benefits are deductible or creditable. We have been historically profitable in the United States. When making our assessment about the realization of its U.S. deferred tax assets as of September 30, 2015, we considered all available evidence, placing particular weight on evidence that could be objectively verified. The evidence considered included the (i) historical profitability of our U.S. operations, (ii) sources of future taxable income, giving weight to sources according to the extent to which they can be objectively verified and (iii) the risks to our business related to the commercialization and development of Vascepa. Based on our assessment, we concluded that the U.S. deferred tax assets are more likely than not to be realizable as of September 30, 2015. The majority of our deferred tax assets are held outside of the United States, for which we have established a full valuation allowance. Changes in historical earnings performance and future earnings projections, among other factors, may cause us to adjust our valuation allowance on deferred tax assets, which would impact our income tax expense in the period in which we determine that these factors have changed. In the event sufficient taxable income is not generated in future periods, additional valuation allowances could be required relating to these U.S. deferred tax assets.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board, or FASB, and are adopted by us as of the specified effective date. We considered the following recent accounting pronouncements which were not yet adopted as of September 30, 2015:

In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606).” This amendment provides principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services, and is effective for annual periods beginning after December 15, 2016 (the original effective date). In April 2015, the FASB issued a proposal, which was subsequently adopted in July 2015, to defer the original effective date of this standard by one year, such that the amendment is effective for our

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fiscal year beginning January 1, 2018. Early adoption is permitted, but not before the original effective date. We are currently evaluating the accounting, transition and disclosure requirements of the standard and cannot currently estimate the financial statement impact of adoption.

In June 2014, the FASB issued guidance for accounting for share-based payments when the terms of an award provide that a performance target could be achieved after the requisite service period. The standard states that a performance target in a share-based payment that affects vesting and that could be achieved after the requisite service period should be accounted for as a performance condition. As such, the performance target should not be reflected in estimating the grant-date fair value of the award. We are required to adopt this standard in the first quarter of fiscal 2016 and early adoption is permitted. This standard is not expected to have an impact on our condensed consolidated financial statements.

In August 2014, the FASB issued ASU No. 2014-15, Presentation of Financial Statements—Going Concern, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40). ASU 2014-15 requires management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards. Specifically, the ASU (i) provides a definition of the term substantial doubt, (ii) requires an evaluation every reporting period including interim periods, (iii) provides principles for considering the mitigating effect of management’s plans, (iv) requires certain disclosures when substantial doubt is alleviated as a result of consideration of management’s plans, (v) requires an express statement and other disclosures when substantial doubt is not alleviated and (vi) requires an assessment for a period of one year after the date that the financial statements are issued (or available to be issued). This standard is effective for fiscal years ending after December 15, 2016, and for annual and interim periods thereafter. Early application is permitted. We are currently evaluating the accounting, transition and disclosure requirements of the standard and cannot currently estimate the financial statement impact of adoption.

In April 2015, the FASB issued ASU No. 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The amendments in this ASU require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. We are required to adopt this standard in the first quarter of fiscal 2016 on a retrospective basis. The implementation of this standard will result in the reclassification of certain debt issuance costs from other assets to a reduction in the carrying amount of the related debt liability within the condensed consolidated balance sheets.

In July 2015, the FASB issued Accounting Standards Update (ASU) No, 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. The amendments in this ASU require that in-scope inventory should be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The amendments do not apply to inventory that is measured using last-in, first-out (LIFO) or the retail inventory method but applies to all other inventory, which include inventory that is measured using first-in, first-out (FIFO) or average cost. This standard is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early application is permitted. We are currently evaluating the accounting, transition and disclosure requirements of the standard and cannot currently estimate the financial statement impact of adoption.

We believe that the impact of other recently issued but not yet adopted accounting pronouncements will not have a material impact on condensed consolidated financial position, results of operations, and cash flows, or do not apply to our operations.

Results of Operations

Comparison of Three Months Ended September 30, 2015 and September 30, 2014

Product Revenue, net. We recorded product revenue of $21.3 million and $14.1 million during the three months ended September 30, 2015 and 2014, respectively, an increase of $7.2 million, or 51%. This increase in revenue was driven by an increase in estimated normalized total Vascepa prescriptions of approximately 67,000 and 63,000 based on data provided by Symphony Health Solutions and IMS Health, respectively, representing growth of 51% and 56%, respectively, over the three months ended September 30, 2014. The level of inventory held by our customers as of September 30, 2015 approximated the inventories held as of September 30, 2014 based on days on hand. All of our product revenue in the three months ended September 30, 2015 and 2014 was derived from product sales of Vascepa, net of allowances, discounts, incentives, rebates, chargebacks and returns. Through September 30, 2015, product returns of Vascepa were de minimis. Timing of shipments to wholesalers, as used for revenue recognition, and timing of prescriptions as estimated by third party sources such as Symphony Health Solutions and IMS Health may differ from period to period.

During the quarters ended September 30, 2015 and 2014, our net product revenue included an adjustment for co-pay mitigation rebates provided by us to commercially insured patients. Such rebates are intended to offset the differential for patients of Vascepa not covered by commercial insurers at the time of launch on Tier 2 for formulary purposes, resulting in higher co-pay

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amounts for such patients. Our cost for these co-payment mitigation rebates was up to $75 per prescription filled prior to February 20, 2014 and up to $70 per prescription filled after February 20, 2014. Since launch, certain third-party payors have added Vascepa to their Tier 2 coverage, which results in lower co-payments for patients covered by these third-party payors. In connection with such Tier 2 coverage, we have agreed to pay customary rebates to these third-party payors on the resale of Vascepa to patients covered by these third-party payors. As a result of expanded commercial coverage and improved formulary positioning, rebates provided for in 2015 will be higher than in prior periods resulting in a slight decrease in the net selling price of Vascepa.

As is typical for the pharmaceutical industry, the majority of Vascepa sales are to major commercial wholesalers which then resell Vascepa to retail pharmacies.

Licensing Revenue. Licensing revenue during the three months ended September 30, 2015 was $0.2 million. We did not record licensing revenue prior to 2015. Licensing revenue relates to the amortization of a $15.0 million up-front payment received in February 2015 associated with a Vascepa licensing agreement for the China Territory. The up-front payment is being recognized over the estimated period in which we are required to provide regulatory and development support and clinical and commercial supply, which is currently anticipated to be a period of approximately 16 years. The amount of licensing revenue recorded may be variable from period to period based on changes in estimates of the timing and level of support required.

Cost of Goods Sold. Cost of goods sold during the three months ended September 30, 2015 and 2014 was $7.5 million and $5.4 million, respectively, an increase of $2.1 million, or 39%. Cost of goods sold includes the cost of API for Vascepa on which revenue was recognized during the period, as well as the associated costs for encapsulation, packaging, shipment, supply management, insurance and quality assurance. The cost of the API included in cost of goods sold reflects the average cost of API included in inventory. This average cost reflects the actual purchase price of Vascepa API.

The API included in the calculation of the average cost of goods sold during the nine months ended September 30, 2015 and 2014 was sourced from three API suppliers. The contracted cost of supply from our initial API supplier is higher than the contracted cost from our other API suppliers. In the future, we anticipate making continued purchases from this initial supplier and to make additional lower unit cost purchases of Vascepa API from other API suppliers. As of September 30, 2015, we classified all of our inventory as current. As a result of lower inventory balances on hand at the end of 2014 compared to the end of 2013 as well as anticipated increases in revenue during 2015 compared to 2014, we anticipate purchasing more API during 2015 than in 2014 with the amount of such purchases dependent on the rate of our revenue growth.

Our gross margin on product sales for the three months ended September 30, 2015 and 2014 was 65% and 62%, respectively. This improvement was primarily driven by lower unit cost API purchases. In addition, over time we expect continued lower average unit cost purchases of API. We also expect that API costs will be lower in the future due to advantages derived from the mix of our suppliers. The average cost may be variable from period to period depending upon the timing and quantity of API purchased from each supplier.

Selling, General and Administrative Expense. Selling, general and administrative expense for the three months ended September 30, 2015 and 2014 was $26.7 million and $19.3 million, respectively, an increase of $7.4 million, or 38%. Selling, general and administrative expenses for the three months ended September 30, 2015 and 2014 are summarized in the table below (in thousands):

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Research and Development Expense. Research and development expense for the three months ended September 30, 2015 and 2014 was $13.1 million and $14.5 million, respectively, a decrease of $1.4 million, or 10%. Research and development expenses for the three months ended September 30, 2015 and 2014 are summarized in the table below (in thousands):

The decrease in research and development expenses for the quarter ended September 30, 2015, as compared to the prior year period, is primarily due to quarterly variability in costs related to the REDUCE-IT study, including the timing of shipment of clinical trial materials.

(Loss) Gain on Change in Fair Value of Derivative Liabilities. (Loss) gain on change in fair value of derivative liabilities for the three months ended September 30, 2015 was a loss of $0.2 million versus a gain of $4.5 million in the prior year period. (Loss) gain on change in fair value of derivative liabilities is comprised of (i) the change in fair value of the warrant derivative liability, (ii) the change in fair value of the derivative liability related to the change in control provision associated with the December 2012

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BioPharma financing, (iii) the change in fair value of the derivative liability related to the change in control provision associated with the May 2014 exchangeable senior notes; and (iv) the change in fair value of the derivative liability related to the preferred stock purchase option.

The warrant derivative liability is related to the change in fair value of warrants issued in conjunction with the October 2009 private placement. In October 2009, we issued 36.1 million warrants at an exercise price of $1.50 and recorded a $48.3 million warrant derivative liability, representing the fair value of the warrants issued. As these warrants have been classified as a derivative liability, they are revalued at each reporting period, with changes in fair value recognized in the statement of operations. In October 2014, we and the holders of the remaining October 2009 warrants mutually agreed to extend the expiration date of such warrants from October 16, 2014 to February 27, 2015. Of the 8,087,388 warrants outstanding as of December 31, 2014, 1,844,585 warrants were exercised and the remaining 6,242,803 warrants expired on February 27, 2015. As such, no warrants were outstanding as of September 30, 2015 and no gain or loss was recognized for the three months ended September 30, 2015. The fair value of the warrant derivative liability as of June 30, 2014 was $4.5 million and we recognized a $4.1 million gain on change in fair value of derivative liability for the three months ended September 30, 2014. The change in fair value of the warrant derivative liability for the quarter ended September 30, 2014 is due primarily to the change in the price of our common stock on the date of valuation.

Our December 2012 financing agreement with BioPharma contains a redemption feature whereby, upon a change of control, we would be required to repay $150 million, less any previously repaid amount. The fair value of the derivative liability is recalculated at each reporting period using a probability-weighted model incorporating management estimates for potential change in control, and by determining the fair value of the debt with and without the change in control provision included. The difference between the two fair values of the debt was determined to be the fair value of the embedded derivative. As of June 30, 2015, the fair value of the derivative was determined to be $5.6 million, and as of September 30, 2015, the fair value of the derivative was determined to be $5.1 million. As such, we recognized a $0.5 million gain on change in fair value of derivative liability for the three months ended September 30, 2015. As of June 30, 2014, the fair value of the derivative was determined to be $6.1 million, and as of September 30, 2014, the fair value of the derivative was determined to be $4.6 million. As such, we recognized a $1.5 million gain on change in fair value of derivative liability for the three months ended September 30, 2014.

Our 2014 Notes, issued in May 2014, contain a redemption feature whereby, upon occurrence of a change in control, we would be required to repurchase the notes. The fair value of the embedded derivative was calculated using a probability-weighted model incorporating management estimates of the probability of a change in control occurring, and by determining the fair value of the debt with and without the change in control provision included. The difference between the two was determined to be the fair value of the embedded derivative. As of June 30, 2015, the fair value of the derivative was determined to be $1.1 million, and as of September 30, 2015, the fair value of the derivative was determined to be $1.8 million. As such, we recognized a $0.7 million loss on change in fair value of derivative liability for the three months ended September 30, 2015. As of June 30, 2014, the fair value of the derivative was determined to be $3.3 million, and as of September 30, 2014, the fair value of the derivative was determined to be $4.4 million. As such, we recognized a $1.1 million loss on change in fair value of derivative liability for the three months ended September 30, 2014.

Any changes in the assumptions used to value the derivative liabilities could result in a material change to the carrying value of such liabilities.

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Interest Expense, net. Net interest expense for the three months ended September 30, 2015 and 2014 was $5.1 million and $4.9 million, respectively, an increase of $0.2 million, or 4%. Net interest expense for the three months ended September 30, 2015 and 2014 is summarized in the table below (in thousands):

Other (Expense) Income, net. Other (expense) income, net, for the three months ended September 30, 2015 was expense of $0.1 million versus expense of $0.2 million in the prior year period. Other (expense) income, net, primarily consists of losses and gains on foreign exchange transactions.

Benefit from (Provision for) Income Taxes. Benefit from (provision for) income taxes for the three months ended September 30, 2015 was a $0.5 million benefit versus a $0.4 million provision in the prior year period. The current benefit (provision) relates entirely to the U.S. subsidiary operations. We are profitable in the United States as a result of intercompany transactions between our U.S. subsidiary and our other companies.

Comparison of Nine Months Ended September 30, 2015 and September 30, 2014

Product Revenue, net. We recorded product revenue of $54.6 million and $37.7 million during the nine months ended September 30, 2015 and 2014, respectively, an increase of $16.9 million, or 45%. This increase in revenue was driven by an increase in estimated normalized total Vascepa prescriptions of approximately 194,000 and 186,000 based on data provided by Symphony Health Solutions and IMS Health, respectively, representing growth of 58% and 65%, respectively, over the nine months ended September 30, 2014. The difference in the percentage of revenue growth as compared to the percentage of prescription growth is primarily due to a change in revenue recognition methodology in 2014 as described below. The level of inventory held by our customers as of September 30, 2015 approximated the inventories held as of September 30, 2014 based on days on hand. All of our product revenue in the nine months ended September 30, 2015 and 2014 was derived from product sales of Vascepa, net of allowances, discounts, incentives, rebates, chargebacks and returns. In accordance with GAAP, prior to 2014, product revenue was recognized based on the resale of Vascepa for the purposes of filling patient prescriptions and not based on sales to our Distributors. During the three months ended March 31, 2014, we concluded that we had developed sufficient history such that we can reliably estimate returns and, as a result, began to recognize product revenue based on sales to our Distributors. Through September 30, 2015, product returns of Vascepa were de minimis. Timing of shipments to wholesalers, as used for revenue recognition, and timing of prescriptions as estimated by third party sources such as Symphony Health Solutions and IMS Health may differ from period to period.

During the nine months ended September 30, 2015 and 2014, our net product revenue included an adjustment for co-pay mitigation rebates provided by us to commercially insured patients. Such rebates are intended to offset the differential for patients of

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Vascepa not covered by commercial insurers at the time of launch on Tier 2 for formulary purposes, resulting in higher co-pay amounts for such patients. Our cost for these co-payment mitigation rebates was up to $75 per prescription filled prior to February 20, 2014 and up to $70 per prescription filled after February 20, 2014. Since launch, certain third-party payors have added Vascepa to their Tier 2 coverage, which results in lower co-payments for patients covered by these third-party payors. In connection with such Tier 2 coverage, we have agreed to pay customary rebates to these third-party payors on the resale of Vascepa to patients covered by these third-party payors. As a result of expanded commercial coverage and improved formulary positioning, rebates provided for in 2015 will be higher than in prior periods resulting in a slight decrease in the net selling price of Vascepa.

As is typical for the pharmaceutical industry, the majority of Vascepa sales are to major commercial wholesalers which then resell Vascepa to retail pharmacies.

Licensing Revenue. Licensing revenue during the nine months ended September 30, 2015 was $0.5 million. We did not record licensing revenue prior to 2015. The licensing revenue relates to the amortization of a $15.0 million up-front payment received in February 2015 associated with a Vascepa licensing agreement for the China Territory. The up-front payment is being recognized over the estimated period in which we are required to provide regulatory and development support and clinical and commercial supply, which is currently anticipated to be a period of approximately 16 years. The amount of licensing revenue recorded may be variable from period to period based on changes in estimates of the timing and level of support required.

Cost of Goods Sold. Cost of goods sold during the nine months ended September 30, 2015 and 2014 was $19.5 million and $14.6 million, respectively, an increase of $4.9 million, or 34%. Cost of goods sold includes the cost of API for Vascepa on which revenue was recognized during the period, as well as the associated costs for encapsulation, packaging, shipment, supply management, insurance and quality assurance. The cost of the API included in cost of goods sold reflects the average cost of API included in inventory. This average cost reflects the actual purchase price of Vascepa API.

The API included in the calculation of the average cost of goods sold for the nine months ended September 30, 2015 and 2014 was sourced from three API suppliers. The contracted cost of supply from our initial API supplier was higher than the contracted cost from our other API suppliers. In the future, we anticipate making continued purchases from this initial supplier and to make additional lower unit cost purchases of Vascepa API from other API suppliers. As of September 30, 2015, we classified all of our inventory as current. As a result of lower inventory balances on hand at the end of 2014 compared to the end of 2013 as well as anticipated increases in revenue during 2015 compared to 2014, we anticipate purchasing more API during 2015 than in 2014 with the amount of such purchases dependent on the rate of our revenue growth.

Our gross margin on product sales for the nine months ended September 30, 2015 and 2014 was 64% and 61%, respectively. This improvement was primarily driven by lower unit cost API purchases. In addition, over time we expect continued lower average unit cost purchases of API. We also expect that API costs will be lower in the future due to advantages derived from the mix of our suppliers. The average cost may be variable from period to period depending upon the timing and quantity of API purchased from each supplier.

Selling, General and Administrative Expense. Selling, general and administrative expense for the nine months ended September 30, 2015 and 2014 was $77.5 million and $60.9 million, respectively, an increase of $16.6 million, or 27%. Selling, general and administrative expenses for the nine months ended September 30, 2015 and 2014 are summarized in the table below (in thousands):

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Research and Development Expense. Research and development expense for the nine months ended September 30, 2015 and 2014 was $37.7 million and $37.9 million, respectively, a decrease of $0.2 million, or 1%. Research and development expenses for the nine months ended September 30, 2015 and 2014 are summarized in the table below (in thousands):

The decrease in research and development expenses for the nine months ended September 30, 2015, as compared to the prior year period, is primarily due to quarterly variability in costs related to the REDUCE-IT study partially offset by an increase in internal staffing and overhead and non-cash stock-based compensation.

(Loss) Gain on Change in Fair Value of Derivative Liabilities. (Loss) gain on change in fair value of derivative liabilities for the nine months ended September 30, 2015 was a loss of $0.4 million versus a gain of $11.9 million in the prior year period. (Loss) gain on change in fair value of derivative liabilities is comprised of (i) the change in fair value of the warrant derivative liability, (ii) the change in fair value of the derivative liability related to the change in control provision associated with the December 2012

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BioPharma financing, (iii) the change in fair value of the derivative liability related to the change in control provision associated with the May 2014 exchangeable senior notes; and (iv) the change in fair value of the derivative liability related to the preferred stock purchase option.

The warrant derivative liability is related to the change in fair value of warrants issued in conjunction with the October 2009 private placement. In October 2009, we issued 36.1 million warrants at an exercise price of $1.50 and recorded a $48.3 million warrant derivative liability, representing the fair value of the warrants issued. As these warrants have been classified as a derivative liability, they are revalued at each reporting period, with changes in fair value recognized in the statement of operations. The fair value of the warrant derivative liability as of December 31, 2014 was $0.1 million and we recognized a $0.1 million gain on change in fair value of derivative liability for the nine months ended September 30, 2015 for these warrants. The fair value of the warrant derivative liability as of December 31, 2013 was $6.9 million and we recognized a $6.3 million gain on change in fair value of derivative liability for the nine months ended September 30, 2014. The change in fair value of the warrant derivative liability for the nine months ended September 30, 2015 is due to the expiration of the warrants and the resulting extinguishment of the liability, while the change in fair value for the nine months ended September 30, 2014 is due primarily to the change in the price of our common stock on the date of valuation. In October 2014, we and the holders of the remaining October 2009 warrants mutually agreed to extend the expiration date of such warrants from October 16, 2014 to February 27, 2015. Of the 8,087,388 warrants outstanding as of December 31, 2014, 1,844,585 warrants were exercised and the remaining 6,242,803 warrants expired on February 27, 2015. As such, no warrants were outstanding as of September 30, 2015.

Our December 2012 financing agreement with BioPharma contains a redemption feature whereby, upon a change of control, we would be required to repay $150 million, less any previously repaid amount. The fair value of the derivative liability is recalculated at each reporting period using a probability-weighted model incorporating management estimates for potential change in control, and by determining the fair value of the debt with and without the change in control provision included. The difference between the two fair values of the debt was determined to be the fair value of the embedded derivative. As of December 31, 2014, the fair value of the derivative was determined to be $4.8 million, and as of September 30, 2015, the fair value of the derivative was determined to be $5.1 million. As such, we recognized a $0.3 million loss on change in fair value of derivative liability for the nine months ended September 30, 2015. As of December 31, 2013, the fair value of the derivative was determined to be $11.1 million, and as of September 30, 2014, the fair value of the derivative was determined to be $4.6 million. As such, we recognized a $6.5 million gain on change in fair value of derivative liability for the nine months ended September 30, 2014.

Our 2014 Notes, issued in May 2014, contain a redemption feature whereby, upon occurrence of a change in control, we would be required to repurchase the notes. The fair value of the embedded derivative was calculated using a probability-weighted model incorporating management estimates of the probability of a change in control occurring, and by determining the fair value of the debt with and without the change in control provision included. The difference between the two was determined to be the fair value of the embedded derivative. As of December 31, 2014, the fair value of the derivative was determined to be $2.6 million, and as of September 30, 2015, the fair value of the derivative was determined to be $1.8 million. As such, we recognized a $0.8 million gain on change in fair value of derivative liability for the nine months ended September 30, 2015. As of September 30, 2014, the fair value of the derivative was determined to be $4.4 million and we recognized a $0.9 million loss on change in fair value of derivative liability for the nine months ended September 30, 2014.

In connection with the closing of a private placement transaction in March 2015, we recorded a derivative liability pursuant to a pre-existing contractual right. This preferred stock purchase option was determined to be a derivative liability effective March 5, 2015, the date in which the private placement was initially subscribed. The fair value of this liability was calculated using a Black-Scholes model and was determined to be $0.9 million at inception and was charged to accumulated deficit as a deemed non-cash dividend. The liability was then marked to fair value through March 30, 2015, the date on which we executed a subscription agreement with the investor, resulting in a charge of $0.9 million through (loss) gain on change in fair value of derivatives in the nine months ended September 30, 2015. The liability was reclassified to permanent equity on such date.

Any changes in the assumptions used to value the derivative liabilities could result in a material change to the carrying value of such liabilities.

Gain on Extinguishment of Debt. On May 15, 2014, we entered into separate, privately negotiated exchange agreements with certain holders of our exchangeable senior notes pursuant to which we exchanged $118.7 million in aggregate principal amount of existing exchangeable senior notes for $118.7 million in aggregate principal amount of new 3.50% exchangeable senior notes due 2032. The key changes in the terms of the new notes included moving the first put date from January 2017 to January 2019, adding an issuer conversion option whereby we can opt to convert the notes into equity should the Daily VWAP (as defined in the Indenture) exceed $2.86 for a certain number of days and reducing the conversion price (see Note 6). As a result of the exchange, we assessed the value of the notes immediately prior to the exchange and immediately after the exchange and determined that the exchange resulted in a substantial modification of the terms of the notes resulting in an extinguishment of the original notes. We recorded a gain on extinguishment of the original notes of $38.0 million in the nine months ended September 30, 2014. There was no such gain in the nine months ended September 30, 2015.

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Interest Expense, net. Net interest expense for the nine months ended September 30, 2015 and 2014 was $14.8 million and $13.6 million, respectively, an increase of $1.2 million, or 9%. Net interest expense for the nine months ended September 30, 2015 and 2014 is summarized in the table below (in thousands):

Other (Expense) Income, net. Other (expense) income, net, for the nine months ended September 30, 2015 was expense of $0.1 million versus income of $4.0 million in the prior year period. Other (expense) income, net, in the nine months ended September 30, 2015 primarily consists of losses and gains on foreign exchange transactions. Other (expense) income, net in the nine months ended September 30, 2014 primarily consists of $4.1 million received in the second quarter of 2014 with respect to settlement agreements with one of our suppliers and one of our encapsulators that provided for the reimbursement of certain amounts previously paid by us.

Benefit from (Provision for) Income Taxes. Benefit from (provision for) income taxes for the nine months ended September 30, 2015 was a $1.5 million benefit versus a $1.3 million provision in the prior year period. The current benefit (provision) relates entirely to the U.S. subsidiary operations. We are profitable in the United States as a result of intercompany transactions between our U.S. subsidiary and our other companies.

Liquidity and Capital Resources

Our sources of liquidity as of September 30, 2015 include cash and cash equivalents of $119.0 million. In February 2015, we received a $15.0 million non-refundable, up-front payment upon the execution of our first ex-U.S. licensing agreement which agreement covers China and surrounding territories. In March 2015, we entered into a subscription agreement with four institutional investors for the issuance and sale of our Series A Preference Shares resulting in net proceeds to us of $52.0 million. Also in March 2015, we entered into a separate subscription agreement with an existing investor, Sofinnova Venture Partners VII L.P. (Sofinnova), for the issuance and sale of our Series A Preference Shares resulting in net proceeds to us of $5.7 million upon closing of the private placement in July 2015. Both the $15.0 million up-front payment from the ex-U.S. licensing agreement and the $57.7 million in net

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proceeds from the issuance and sale of Series A Preference Shares are included in our September 30, 2015 cash balance. Our projected uses of cash include commercialization of Vascepa , the continued funding of the REDUCE-IT cardiovascular outcomes study, working capital and other general corporate activities. Our cash flows from operating, investing and financing activities, as reflected in the condensed consolidated statements of cash flows, are summarized in the following table (in thousands):

On December 6, 2012 we entered into a financing agreement with BioPharma. Under this agreement, we granted to BioPharma a security interest in future receivables associated with Vascepa patent rights, in exchange for $100 million received at the closing of the agreement which closing occurred in December 2012. We have agreed to repay BioPharma up to $150 million of future revenue and receivables. As of September 30, 2015, the net remaining amount to be repaid to BioPharma is $139.4 million. To date, our revenues have been below the contractual threshold amount such that each payment made has reflected the calculated optional reduction amount as opposed to the contractual threshold payments for each quarterly period. The maximum amount payable under the contractual threshold for 2015 is $15.0 million. The quarterly repayments through September 30, 2015 represented interest only. In accordance with the agreement with BioPharma, quarterly differences between the calculated optional reduction amounts and the repayment schedule amounts are rescheduled for payment beginning in the second quarter of 2017. Any such deferred payments will remain subject to continued application of the quarterly ceiling in amounts due established by the calculated threshold based on quarterly Vascepa revenues. No additional interest expense or liability is incurred as a result of such deferred repayments and no cliff payment of the remaining balance is due except in the event of Company default or Company change of control. The agreement does not expire until $150 million in aggregate has been repaid. We can prepay an amount equal to $150 million less any previously repaid amount. We currently estimate that Vascepa revenue levels will not be high enough in each quarter to support repayment to BioPharma in accordance with threshold amounts in the repayment schedule.

On January 9, 2012, Amarin, through our wholly-owned subsidiary Corsicanto Limited, or Corsicanto, a private limited company incorporated under the laws of Ireland, completed a private placement of $150.0 million in aggregate principal amount of its 3.5% exchangeable senior notes due 2032, or the 2012 Notes. The proceeds we received from the January 2012 debt offering were approximately $144.3 million, net of fees and transaction costs. On May 20, 2014, we entered into separate, privately negotiated exchange agreements with certain holders of the 2012 Notes pursuant to which Corsicanto exchanged $118.7 million in aggregate principal amount of the 2012 Notes for $118.7 million in aggregate principal amount of new 3.50% May 2014 Exchangeable Senior Notes due 2032, or the 2014 Notes, following which $31.3 million in aggregate principal amount of the 2012 Notes remain outstanding with terms unchanged.

The 2012 Notes were issued pursuant to an indenture dated as of January 9, 2012, by and among Corsicanto, us as guarantor, and Wells Fargo Bank, National Association, as trustee. The notes are the senior unsecured obligations of Corsicanto and are guaranteed by us. The 2012 Notes bear interest at a rate of 3.5% per annum, payable semi-annually in arrears on January 15 and July 15 of each year, beginning on July 15, 2012. The notes mature on January 15, 2032, unless earlier repurchased, redeemed or exchanged. On or after January 19, 2017, we may elect to redeem for cash all or a portion of the notes for the principal amount of the notes plus accrued and unpaid interest. On each of January 19, 2017, January 19, 2022 and January 19, 2027, the holders of the notes may require that we repurchase in cash the principal amount of the notes plus accrued and unpaid interest. At any time prior to January 15, 2032, upon certain circumstances, which circumstances include our issuing a notice of redemption to the note holders, the price of our shares trading above 130% of the exchange price, or certain other events defined in the note agreement, the holders of the notes may elect to convert the notes. The exchange rate for conversion is 113.4752 ADSs per $1,000 principal amount of the notes (equivalent to an initial exchange price of approximately $8.8125 per ADS), subject to adjustment in certain circumstances, including adjustment if we pay cash dividends. Upon exchange, the notes may be settled, at our election, subject to certain conditions, in cash, ADSs or a combination of cash and ADSs.

The 2014 Notes were issued pursuant to an indenture dated May 20, 2014 by and among Corsicanto, us as grantor, and Wells Fargo Bank, National Association, as trustee. The notes are senior unsecured obligations of Corsicanto and are guaranteed by us. The 2014 Notes have a stated interest rate of 3.5% per year, payable semiannually in arrears on January 15 and July 15 of each year beginning on July 15, 2014, and ending upon the Notes’ maturity on January 15, 2032, unless earlier repurchased or redeemed by Corsicanto or exchanged by the holders. At any time after the issuance of the 2014 Notes and prior to the close of business on the

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second business day immediately preceding January 15, 2032, holders may exchange their 2014 Notes at their option. If prior to January 15, 2018, a make-whole fundamental change (as defined in the Indenture) occurs or we elect to redeem the 2014 Notes in connection with certain changes in tax law, in each case as described in the Indenture, and a holder elects to exchange its 2014 Notes in connection with such make-whole fundamental change or election, as the case may be, such holder may be entitled to an increase in the exchange rate as described in the Indenture. The initial exchange rate is 384.6154 ADSs per $1,000 principal amount of the 2014 Notes (equivalent to an initial exchange price of approximately $2.60 per ADS, or the Exchange Price), subject to adjustment in certain circumstances. The exchange rate is subject to adjustment from time to time upon the occurrence of certain events, including, but not limited to, the payment of cash dividends.

On March 30, 2015, in connection with the closing of the initial private placement, and pursuant to a pre-existing contractual preemptive right to participate in certain private placement transactions effected by us, we entered into a separate subscription agreement with an existing investor, Sofinnova Venture Partners VII L.P. (Sofinnova), for the purchase of an additional 38,867,180 restricted ADSs, each representing one (1) share of our Series A Preference Shares, at the same price per share and otherwise on substantially the same terms as the initial private placement, for potential proceeds of $5.8 million. In accordance with applicable marketplace rules of the NASDAQ Stock Market, the consummation of the second private placement was conditioned upon approval by our shareholders at a future meeting of our shareholders. Such approval was received at our Annual General Meeting of Shareholders on July 6, 2015 and as a result, the closing of this second private placement occurred on July 10, 2015. We issued 38,867,180 restricted ADSs, each representing one Series A Preference Share, which may be consolidated and redesignated from time to time up to a maximum of 3,886,718 ordinary shares, each ordinary share to be represented by one ADS (see Note 8 – Equity). For each restricted ADS, Sofinnova paid a negotiated price of $0.15 (equating to $1.50 on an as converted to ordinary share basis) resulting in gross proceeds to us of $5.8 million. Dr. James Healy, a member of our Board, is a managing member of Sofinnova Management VII, L.L.C., the general partner of Sofinnova.

As of September 30, 2015, we had cash and cash equivalents of $119.0 million, a decrease of $0.5 million from December 31, 2014. The decrease is primarily due to the net proceeds from equity financings of $57.7 million and a $15.0 million up-front payment received from an ex-U.S. licensing agreement offset by net cash used in operating activities in support of the continued commercialization of Vascepa and the continued funding of REDUCE-IT, less accounts receivable collections. We have incurred annual operating losses since our inception and, as a result, we had an accumulated deficit of $1.1 billion as of September 30, 2015. We believe that our cash and cash equivalents balance of $119.0 million as of September 30, 2015 will be sufficient to fund our projected operations for at least the next twelve months. We anticipate that quarterly net cash outflows in future periods will be variable.

Contractual Obligations

We have Vascepa API supply agreements with three independent companies from which we purchase qualified API supply: Nisshin, Chemport and Finorga SAS, or Novasep. We also have encapsulation agreements with three FDA-approved commercial API encapsulators for Vascepa manufacturing: Patheon, Inc. (formerly Banner Pharmacaps), Catalent Pharma Solutions, and Capsugel Plöermel SAS, LLC, or Capsugel. Our agreements with Chemport, Novasep, and Capsugel contain minimum annual purchase levels to enable us to maintain certain supply exclusivity and also contain a provision that any shortfall in the minimum purchase commitments is payable in cash. Each supplier is required to meet certain performance obligations and the agreements may be terminated by us in the event of non-performance.

We have operating lease costs consisting of leases for facilities in Dublin, Ireland and Bedminster, NJ.

We have scheduled interest payments due under the terms of the 2012 Notes and 2014 Notes, assuming that the 2012 Notes remain outstanding through January 19, 2017 and that the 2014 Notes remain outstanding through January 19, 2019 and they have not been exchanged for ADSs.

Under the 2004 share repurchase agreement with Laxdale Limited, or Laxdale, upon approval of Vascepa by the FDA on July 26, 2012, we were required to make a milestone payment to Laxdale of £7.5 million. We made this payment in 2012 and capitalized this Laxdale milestone payment of $11.6 million as a component of other long-term assets. This long-term asset is being amortized over the estimated useful life of the intellectual property we acquired from Laxdale and we recognized amortization expense of $0.5 million in each of the nine months ended September 30, 2015 and 2014. Also under the Laxdale agreement, upon receipt of marketing approval in Europe for the first indication for Vascepa (or first indication of any product containing Amarin Neuroscience intellectual property acquired from Laxdale in 2004), we must make an aggregate stock or cash payment to the former shareholders of Laxdale (at the sole option of each of the sellers) of £7.5 million (approximately $11.4 million as of September 30, 2015). Additionally, upon receipt of a marketing approval in the United States or Europe for a further indication of Vascepa (or further indication of any other product using Amarin Neuroscience intellectual property), we must make an aggregate stock or cash payment (at the sole option of each of the sellers) of £5 million (approximately $7.6 million as of September 30, 2015) for each of the two potential market approvals (i.e. £10 million maximum, or approximately $15.2 million as of September 30, 2015).

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In January 2015, we granted a total of 5,455,500 performance-based RSUs (“PSUs”) to employees for the right to receive payment in the form of ordinary shares, or any combination of cash and shares. Payment in the form of ordinary shares was subject to shareholder approval of a sufficient increase in the number of shares reserved for issuance under the Amarin Corporation plc 2011 Stock Incentive Plan. Such shareholder approval was obtained at our Annual General Meeting on July 6, 2015.

We have recorded a liability of $0.4 million for uncertain tax positions in other long-term liabilities as of September 30, 2015. We are not able to reasonably estimate in which future periods these amounts will ultimately be settled.

We do not enter into financial instruments for trading or speculative purposes. As of September 30, 2015, we had no outstanding forward exchange contracts.

Off-Balance Sheet Arrangements

We do not have any special purpose entities or other off-balance sheet arrangements.

There have been no material changes with respect to the information appearing in PART II, Item 7A “Quantitative and Qualitative Disclosures about Market Risk” of our Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 3, 2015.

Evaluation of Disclosure Controls and Procedures

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in the reports that we file or submit under the Securities Exchange Act of 1934 is (1) recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms and (2) accumulated and communicated to our management, including our principal executive officer and principal financial officer, to allow timely decisions regarding required disclosure.

As of September 30, 2015, our management, with the participation of our principal executive officer and principal financial officer, evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934). Our management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives, and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Our principal executive officer and principal financial officer have concluded, based upon the evaluation described above that, as of September 30, 2015, our disclosure controls and procedures were effective at the reasonable assurance level.

Changes in Internal Control over Financial Reporting

During the quarter ended September 30, 2015, there have been no changes in our internal control over financial reporting, as such term is defined in Rules 13a-15(f) and 15(d)-15(f) promulgated under the Securities Exchange Act of 1934, that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II

In the ordinary course of business, we are from time to time involved in lawsuits, claims, investigations, proceedings, and threats of litigation relating to our business. “Item 3. Legal Proceedings” of our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 includes a discussion of our current legal proceedings. There have been no material changes to those disclosures as of the date of this filing other than as set forth below.

On May 7, 2015, we and a group of independent physicians filed a federal lawsuit to permit us to share truthful and non-misleading information, including, but not limited to, the ANCHOR trial clinical data, with healthcare professionals in the United States about certain uses of Vascepa not included with approved FDA labeling of Vascepa and thus not permitted under the FDA’s interpretation of applicable law. The lawsuit, captioned Amarin Pharma, Inc., et al. v. Food & Drug Administration, et al. (1:15-cv-03588-PAE), was filed in the United States District Court for the Southern District of New York and seeks a judicial declaration based on several legal theories. On August 7, 2015, the Court granted our request for preliminary relief in this litigation through a declaratory judgment that confirmed that we may engage in truthful and non-misleading speech promoting the off-label use of Vascepa, i.e., to treat patients with persistently high triglycerides, and such speech may not form the basis of a misbranding action under the Federal Food and Drug Cosmetic Act. FDA did not appeal the Court’s preliminary ruling prior to the October 6, 2015 deadline for appeal. The underlying litigation has been stayed for settlement discussion and the parties are working toward settlement. We cannot predict the outcome of settlement negotiations or this litigation.

On May 28, 2015, the U.S. District Court for the District of Columbia granted our motion for summary judgment in our lawsuit against the FDA, captioned Amarin Pharmaceuticals Ireland Ltd. v. Food & Drug Administration, et al., Civ. A. No. 14-0324 (D.D.C.). This lawsuit sought an order requiring FDA to recognize five-year, New Chemical Entity (“NCE”) marketing exclusivity for Vascepa. The decision vacated the FDA’s denial of our claim for such exclusivity and remanded to the FDA for proceedings consistent with the decision. On July 22, 2015, Watson Laboratories Inc., the purported first Vascepa ANDA filer, sought to intervene and appeal the Court’s decision. We intend to continue to litigate the case vigorously, but cannot predict the outcome of this litigation. FDA did not appeal the Court’s decision prior to the July 28, 2015 deadline for appeal.

Based on the May 28, 2015, U.S. District Court for the District of Columbia order granting our motion for summary judgment in the NCE litigation, on June 26, 2015, the parties to the related Vascepa patent litigation that followed acceptance by FDA of abbreviated new drug applications, or ANDAs, to Vascepa agreed to a full stay of proceeding in that patent litigation. Based on subsequent FDA notification to the ANDA filers that FDA had changed the status of their ANDAs to submitted, but no longer accepted, we believe the statutory basis for the patent litigation (accepted ANDAs) no longer exists. Thus, on July 24, 2015, we moved to dismiss the pending patent infringement lawsuits against each of the Vascepa ANDA applicants. We intend to vigorously enforce our intellectual property rights relating to Vascepa consistent with the time period contemplated by the Hatch-Waxman Act, but we cannot predict the outcome of these lawsuits. We cannot predict the outcome of this motion to dismiss or litigation. If the motion to dismiss is granted, we plan to defend the exclusivity of Vascepa through patent litigation after notification that FDA has accepted an ANDA application related to Vascepa which, assuming NCE exclusivity, we would expect no sooner than late July 2016.

On June 29, 2015, the U.S. District Court for the District of New Jersey granted our motion to dismiss the putative consolidated class action lawsuit captioned In re Amarin Corporation plc, Securities Litigation, No. 3:13-cv-06663 (D.N.J. Nov. 1, 2013). The class action was dismissed without prejudice with leave for plaintiffs to file an amended complaint. The lawsuit sought unspecified monetary damages and attorneys’ fees and costs alleging that we and certain of our current and former officers and directors made misstatements and omissions regarding the FDA’s willingness to approve Vascepa’s ANCHOR indication and related contributing factors and the potential relevance of data from the ongoing REDUCE-IT trial to that potential approval. On July 29, 2015, plaintiffs filed an amended complaint alleging facts similar to those in the original complaint. Like the first complaint, the amended complaint seeks unspecified monetary damages and attorneys’ fees and costs. We believe we have valid defenses and will continue to vigorously defend against this lawsuit, but cannot predict the outcome. We have insurance coverage that is anticipated to cover any significant loss exposure that may arise from this action.

This Quarterly Report on Form 10-Q contains forward-looking information based on our current expectations. Because our actual results may differ materially from any forward-looking statements that we make or that are made on our behalf, this section includes a discussion of important factors that could affect our actual future results, including, but not limited to, our capital resources, our ability to successfully commercially launch Vascepa, the progress and timing of our clinical programs, the safety and efficacy of our product candidates, risks associated with regulatory filings, the potential clinical benefits and market potential of our product candidates, commercial market estimates, future development efforts, patent protection, effects of healthcare reform, reliance on third parties, and other risks set forth below.

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Those risk factors below denoted with a “*” are newly added or have been materially updated from our Annual Report on Form 10-K filed with the SEC on March 3, 2015.

Risks Related to the Commercialization and Development of Vascepa

*We are substantially dependent upon sales of Vascepa in the United States.

As a result of our reliance on a single product, Vascepa (icosapent ethyl) capsules, and our primary focus on the U.S. market in the near-term, much of our near-term results and value as a company depends on our ability to execute our commercial strategy for Vascepa in the United States. If commercialization efforts for Vascepa are not successful, our business will be materially and adversely affected.

Even if we are able to develop Vascepa outside the United States or develop additional products from our research and development efforts, the development time cycle for products typically takes several years. This restricts our ability to respond to adverse business conditions for Vascepa. If we are not successful with development, or if there is not adequate demand for Vascepa or the market for such product develops less rapidly than we anticipate, we may not have the ability to effectively shift our resources to the development of alternative products or do so in a timely manner without suffering material adverse effects on our business. As a result, the lack of alternative markets and products we develop could constrain our ability to generate revenues and achieve profitability.

*The uncertain effect of Vascepa on its ultimate targeted clinical benefit makes it more difficult to achieve a level of market acceptance by physicians, patients, healthcare payors and others in the medical community necessary for commercial success.

In January 2013, we launched Vascepa based on FDA approval of our MARINE indication, for use as an adjunct to diet to reduce triglyceride levels in adult patients with severe (TG ³500 mg/dL) hypertriglyceridemia. Approximately 4.0 million people in the United States have severely high triglyceride levels (TG >500 mg/dL), commonly known as very high triglyceride levels. Guidelines for the management of very high triglyceride levels suggest that reducing triglyceride levels is the primary goal in patients to reduce the risk of acute pancreatitis. A secondary goal for this patient population is to reduce cardiovascular risk. The effect of Vascepa on cardiovascular mortality and morbidity, or the risk for pancreatitis, in patients with hypertriglyceridemia has not been determined and our FDA-approved labeling and promotional efforts state these facts.

In August 2015, based on a federal court order, we also began marketing Vascepa in the United States to healthcare professionals for the treatment of patients with high (TG ³200 mg/dL and <500 mg/dL) triglyceride levels who are also on statin therapy for elevated low-density lipoprotein cholesterol, or LDL-C, levels, based on results from the ANCHOR study of Vascepa. It is estimated that approximately 40 million adults in the United States have high triglyceride levels (TG >200 mg/dL), and many patients with high triglycerides also have other lipid level abnormalities such as high cholesterol and are on statin therapy. FDA did not approve Vascepa for use in this population due to the uncertain effect of pharmaceutically induced triglyceride reduction in this patient population on cardiovascular risk reduction, the ultimate targeted clinical benefit. Our promotional efforts disclose this fact and the current state of research on both triglyceride reduction and the active pharmaceutical ingredient in Vascepa, EPA, as each relate to the potential of Vascepa to reduce cardiovascular risk.

The uncertainties around the ultimate clinical benefit of Vascepa make it more difficult for Vascepa to gain market acceptance by physicians, patients, healthcare payors and others in the medical community. If Vascepa does not achieve an adequate level of acceptance, we may not generate significant product revenues and we may not become profitable. The degree of market acceptance of Vascepa for the MARINE indication and in ANCHOR patients and any future approved indications will depend on a number of factors, including:

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*Our current and planned commercialization efforts may not be successful in increasing sales of Vascepa.

In January 2013, we began selling and marketing Vascepa in the United States through our own, newly established sales and marketing teams and through a newly established third-party commercial distribution infrastructure. We hired key personnel in these areas over the last several years and hired and trained a professional sales force in early January 2013. In October 2013, following an FDA advisory committee recommendation against approval for the ANCHOR indication, we implemented a plan to reduce our workforce and our team of sales professionals in half.

In May 2014 we began co-promoting Vascepa in the United States with Kowa Pharmaceuticals America, Inc. under a co-promotion agreement we entered into in March 2014. Under the agreement, approximately 250 Kowa Pharmaceuticals America, Inc. sales representatives devote a substantial portion of their time to promoting Vascepa with Amarin’s approximately 130 sales representatives based on a plan designed to substantially increase both the number of sales targets reached and the frequency of sales calls on existing sales targets. However, the commercialization of a new pharmaceutical product is a complex undertaking for a company to manage, and we have very limited experience as a company operating in this area and co-promoting a pharmaceutical product with a partner.

We are also expanding our commercialization activities to markets outside of the United States through partnering arrangements. On February 26, 2015, we entered into a Development, Commercialization and Supply Agreement (the “DCS Agreement”) with Eddingpharm (Asia) Macao Commercial Offshore Limited (“Eddingpharm”) related to the development and commercialization of Vascepa in Mainland China, Hong Kong, Macau and Taiwan (the “China Territory”). Under the DCS Agreement, Eddingpharm will be solely responsible for development and commercialization activities in the China Territory and associated expenses. Significant commercialization of Vascepa in the China Territory is several years away. If Eddingpharm is not able to effectively develop and commercialize Vascepa in the China Territory, we may not be able to generate revenue from the DCS Agreement resulting from the sale of Vascepa in the China Territory.

We have limited experience working with ex-U.S. partners such as Eddingpharm to develop and market our products in foreign countries. In order for Eddingpharm, or us, to market and sell Vascepa in any country outside of the United States for any indication, it will be necessary to obtain regulatory approval from the appropriate regulatory authorities. The requirements and timing for regulatory approval vary widely from country to country and may in some cases be different than or more rigorous than requirements in the United States. Any failure by us or Eddingpharm to obtain approval for Vascepa in any countries outside of the United States in a timely manner may limit the commercial success of Vascepa and our ability to grow our revenues.

Factors related to building and managing a sales and marketing organization that can inhibit our efforts to successfully commercialize Vascepa include:

If we are not successful in our efforts to market and sell Vascepa, our anticipated revenues will be materially and negatively affected, and we may not obtain profitability, may need to cut back on research and development activities or need to raise additional funding that could result in substantial dilution.

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*We expect final positive results from the REDUCE-IT outcomes study will be required for FDA-approved label expansion for Vascepa.

Since January 2013 we have marketed Vascepa for use in the FDA-approved MARINE indication in the United States.

In April 2015, we received a CRL from the FDA on our Supplemental New Drug Application, or sNDA, that sought approval for the use of Vascepa in patients with high triglyceride levels (TG ³200 mg/dL and <500 mg/dL) who are also on statin therapy, which we refer to as the ANCHOR indication. In regulatory dialogue, the FDA acknowledged that the results of the ANCHOR trial as we presented them to FDA were valid and truthful in that, for example, Vascepa reduced triglyceride levels compared to placebo in patients treated in the ANCHOR study. The clinical rationale for reducing serum triglycerides with Vascepa and modifying other lipid/lipoprotein parameters shown in ANCHOR among statin-treated patients with triglycerides 200-499 mg/dL is to reduce cardiovascular risk. In not approving our ANCHOR sNDA, the FDA concluded that, for regulatory approval purposes, there are insufficient data at this time to support a drug-induced change in serum triglycerides as a surrogate for reducing cardiovascular risk in the ANCHOR population. The FDA did not determine that the drug-induced effects of Vascepa, which go beyond triglyceride-lowering, would not actually reduce cardiovascular risk in this population.

In August 2015, based on a federal court order, we began marketing Vascepa in the United States to healthcare professionals for the treatment of patients in the ANCHOR population through use of a set of qualified statements that reflect the current state of research related to this use. While an indication for this patient population has yet to be granted, our ability to reach full potential in the commercialization of Vascepa in the United States is dependent upon marketing claims associated with Vascepa that are granted with the approval of an indication statement by the FDA.

Based on our communications with the FDA, we expect that final positive results from the REDUCE-IT outcomes study will be required for FDA approval of a new indication or other label expansion for Vascepa. Any delay in obtaining, or an inability to obtain, further expansion of our marketing approval rights with an FDA approval could prevent us from growing revenue at greater than our current pace and could therefore have a material adverse effect on our operations and financial condition, including our ability to reach profitability. Even if we obtain additional regulatory approvals for Vascepa, the timing or scope of any approvals may prohibit or reduce our ability to commercialize the product successfully. For example, if the approval process for any expanded indication takes too long, we may miss market opportunities and give other companies the ability to develop competing products or establish market dominance. If the FDA does not approve any expanded indication at all, it could have a material impact on our future results of operations and financial condition. Additionally, the terms of any approvals, including the approval received from the FDA in July 2012 for the MARINE indication, may prove to not have the scope or breadth needed for us to successfully commercialize Vascepa or become profitable.

*Our lawsuit to allow for promotion of truthful and non-misleading information to healthcare professionals in the United States about uses of Vascepa may not achieve its intended goal.

On May 7, 2015, we and a group of independent physicians filed a lawsuit in federal court to permit us to promote to healthcare professionals certain uses of Vascepa that reflect recognized medical practice but are not covered by current FDA-approved labeling for the drug, so long as the promotion is truthful and non-misleading. The uses at issue are consistent with multiple national and international treatment guidelines and relevant to tens of millions of patients in the United States at risk of cardiovascular disease. Because, for example, the efficacy results from the ANCHOR trial have not been approved by the FDA for inclusion in FDA labeling of Vascepa, truthful and non-misleading promotion of such information is considered off-label and thus illegal under FDA’s interpretation of its regulatory structure. The lawsuit, captioned Amarin Pharma, Inc. et al. v. Food & Drug Administration, et al., was filed in the United States District Court for the Southern District of New York and seeks a judicial declaration based on applicable precedent, First Amendment freedom of speech principles and Fifth Amendment restrictions against overly vague laws. The lawsuit seeks a declaration to permit promotion of the FDA-reviewed and agreed effects of Vascepa demonstrated in the ANCHOR clinical trial and use of peer-reviewed scientific publications that present the current state of scientific research related to the potential of Vascepa to reduce the risk of cardiovascular disease. The physicians in the suit regularly treat patients at risk of cardiovascular disease and, as the complaint contends, have First Amendment rights to receive accurate information. The goal of the lawsuit is to supply accurate information to physicians about Vascepa so they can make informed decisions on how to treat patients based on current, scientific data and consistent with numerous national and international cardiovascular treatment guidelines and position statements.

In connection with this litigation, the FDA sent a detailed letter to us on June 5, 2015 that confirmed the validity of the ANCHOR trial results. The letter also sought to clarify how, in the FDA’s view, applicable law and FDA policies apply to the communications proposed in Amarin’s complaint. FDA stated in this letter that it did not have concerns with much of the information Amarin proposed to communicate and provided Amarin with guidance on the FDA’s view of lawful, but limited paths for the dissemination and communication to healthcare professionals of the effects of Vascepa demonstrated in the ANCHOR clinical trial and use of peer-reviewed scientific publications in the context of appropriate disclaimers. The litigation continued after receipt of this

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letter because significant issues remained despite the significant steps forward provided by the June 5 letter. Such issues included, but were not limited to, the ability of Amarin to engage in a full and truthful dialogue with healthcare professionals about the success of the ANCHOR trial and the potential effectiveness of Vascepa as a treatment to reduce cardiovascular risk.

On August 7, 2015, we were granted the request we made for preliminary relief in this litigation through the Court’s declaratory judgment that confirmed we may engage in truthful and non-misleading speech promoting the off-label use of Vascepa to healthcare professionals, i.e., to treat patients with persistently high triglycerides, and that such speech may not form the basis of a misbranding action under the Federal Food and Drug Cosmetic Act. FDA did not appeal the Court’s preliminary ruling prior to the October 6, 2015 deadline for appeal. The underlying litigation has been stayed for settlement discussion and the parties are working toward settlement. We cannot predict the outcome of settlement negotiations or this litigation. The legal process can be unpredictable, costly and time-consuming and even if we are successful the remedies available to us may be less beneficial to us than we currently believe.

We may not be able to compete effectively against our competitors’ pharmaceutical products.

The biotechnology and pharmaceutical industries are highly competitive. There are many pharmaceutical companies, biotechnology companies, public and private universities and research organizations actively engaged in the research and development of products that may be similar to our products. It is probable that the number of companies seeking to develop products and therapies similar to our products will increase. Many of these and other existing or potential competitors have substantially greater financial, technical and human resources than we do and may be better equipped to develop, manufacture and market products. These companies may develop and introduce products and processes competitive with or superior to ours. In addition, other technologies or products may be developed that have an entirely different approach or means of accomplishing the intended purposes of our products, which might render our technology and products noncompetitive or obsolete.

Our competitors both in the United States and Europe include large, well-established pharmaceutical companies, specialty pharmaceutical sales and marketing companies, and specialized cardiovascular treatment companies. GlaxoSmithKline plc, which currently sells Lovaza^®, a prescription-only omega-3 fatty acid indicated for patients with severe hypertriglyceridemia was approved by FDA in 2004 and has been on the market in the United States since 2005. As described below, multiple generic versions of Lovaza are now available in the United States. Other large companies with competitive products include AbbVie, Inc., which currently sells Tricor^® and Trilipix^® for the treatment of severe hypertriglyceridemia and mixed dyslipidemia and Niaspan^®, which is primarily used to raise HDL-C, but is also used to lower triglycerides. Generic versions of Tricor, Trilipix, and Niaspan are also now available in the United States. In addition, in May 2014, Epanova^® (omega-3-carboxylic acids) capsules, a free fatty acid form of omega-3 (comprised of 55% EPA and 20% DHA), was approved by the FDA for patients with severe hypertriglyceridemia. Epanova was developed by Omthera Pharmaceuticals, Inc., and is now owned by AstraZeneca Pharmaceuticals LP (AstraZeneca). We expect AstraZeneca will utilize its substantial commercial resources to market its product imminently. Also, in April 2014, Omtryg, another omega-3-acid fatty acid composition developed by Trygg Pharma AS, received FDA approval for severe hypertriglyceridemia. We are not aware of the commercialization plan for Omtryg. Each of these competitors, other than Trygg, has greater resources than we do, including financial, product development, marketing, personnel and other resources.

In April 2014, Teva Pharmaceuticals USA Inc., or Teva, launched a generic version of Lovaza after winning its patent litigation against Pronova BioPharma Norge AS, now owned by BASF, which owns such patents rights. In June 2014 and September 2014, Par Pharmaceutical Inc., or Par, and Apotex Inc., or Apotex, received FDA approval of their respective versions of generic Lovaza. In March 2011, Pronova/BASF entered into an agreement with Apotex to settle its patent litigation in the United States related to Lovaza. Pursuant to the terms of the settlement agreement, we believe Pronova/BASF granted Apotex a license to enter the U.S. market with a generic version of Lovaza in the first quarter of 2015, the details of which are not known to us. In the first quarter of 2015, Prasco Labs announced it also has a generic version of Lovaza.

In addition, we are aware of other pharmaceutical companies that are developing products that, if approved and marketed, would compete with Vascepa. We understand that Acasti Pharma, a subsidiary of Neptune Technologies & Bioresources Inc., announced in late 2012 that it intends to conduct a Phase 3 clinical program to assess the safety and efficacy of its omega-3 prescription drug candidate derived from krill oil for the treatment of hypertriglyceridemia. We believe Catabasis Pharmaceuticals, or Catabasis, Resolvyx Pharmaceuticals, or Resolvyx, and Sancilio & Company are also developing potential treatments for hypertriglyceridemia based on omega-3 fatty acids. To our knowledge, Catabasis initiated a Phase 2 clinical trial of its product in December 2013; Resolvyx’s compound remains in Phase 1 clinical testing; and Sancilio is preparing to commence Phase 3 clinical testing. In addition, we are aware that Matinas BioPharma, Inc. is developing an omega-3-based therapeutic for the treatment of severe hypertriglyceridemia and mixed dyslipidemia. Matinas BioPharma, Inc. has filed an Investigational New Drug Application with the FDA to conduct a human study in the treatment of severe hypertriglyceridemia. Isis Pharmaceuticals announced favorable Phase 2 results of ISIS-APOCIII_Rx a drug candidate administered through weekly subcutaneous injections, in patients with high triglycerides and type 2 diabetes and in patients with moderate to severe high triglycerides. Finally, Madrigal Pharmaceuticals has completed Phase 1 clinical testing of MGL-3196 for the treatment of high triglycerides and various lipid parameters in patients.

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*Our suit against FDA challenging its denial of five-year, NCE exclusivity to Vascepa under the Hatch-Waxman Amendments may not achieve its intended goal to delay generic competition challenges to Vascepa.

The timelines and conditions under the ANDA process that permit the start of patent litigation and allow the FDA to approve generic versions of brand name drugs like Vascepa differ based on whether a drug receives three-year, or five-year, new chemical entity (NCE) marketing exclusivity. The FDA typically makes a determination on marketing exclusivity in connection with an NDA approval of a drug for a new indication. We applied to the FDA for five-year, NCE marketing exclusivity for Vascepa in connection with the NDA for our MARINE indication, which NDA was approved by the FDA on July 26, 2012. On February 21, 2014, in connection with the July 26, 2012 approval of the MARINE indication, the FDA denied a grant of NCE marketing exclusivity to Vascepa and granted three-year marketing exclusivity. Under applicable regulations, subject to our related litigation with FDA over NCE marketing exclusivity, such three-year exclusivity would have extended through July 25, 2015 and be supplemented by a 30-month stay that we believe would have extended into September 2016, if the related Vascepa patent litigation were not resolved against us sooner.

NCE marketing exclusivity, not granted to Vascepa at this time, precludes approval during the five-year exclusivity period of certain 505(b)(2) applications and ANDAs submitted by another company for another version of the drug. However, an application may be submitted after four years if it contains a certification of patent invalidity or non-infringement. In this case, the pioneer drug company may be afforded the benefit of a 30-month stay against the launch of such a competitive product that would extend from the end of the five-year exclusivity period, and may also be afforded other extensions under applicable regulations, including a six-month pediatric exclusivity extension or a judicial extension if applicable requirements are met. Another drug sponsor could also gain a form of marketing exclusivity under the provisions of the FDCA, as amended by the Hatch-Waxman Amendments, if such company can, under certain circumstances, complete a human clinical trial process and obtain regulatory approval of its product.

The three-year period of exclusivity granted to Vascepa under the Hatch-Waxman Amendments is for a drug product that contains an active moiety that has been previously approved when the application contains reports of new clinical investigations (other than bioavailability studies) conducted by the sponsor that were essential to approval of the application. Our MARINE clinical trial was a new clinical investigation that was essential to the approval of our new drug application. We are entitled to three-year exclusivity even though FDA determined that the EPA moiety was previously approved in Lovaza because our MARINE clinical investigation was essential for the approval of our new drug product, Vascepa.

Such three-year exclusivity protection precludes the FDA from approving a marketing application for an ANDA, a product candidate that the FDA views as having the same conditions of approval as Vascepa (for example, the same indication and/or other conditions of use), or a 505(b)(2) NDA submitted to the FDA with Vascepa as the reference product, for a period of three years from the date of FDA approval. The FDA may accept and commence review of such applications during the three-year exclusivity period. Such three-year exclusivity grant does not prevent a company from challenging the validity of our patents at any time. In this case, Amarin would be, and has been, afforded the benefit of a 30-month stay against the launch of such a competitive product that extends from the period that Amarin receives notice of the patent challenge (the paragraph IV notice), assuming Amarin responds to the patent challenge within 45 days, and Amarin may also be afforded a judicial extension if applicable requirements are met. This three-year form of exclusivity may also not prevent the FDA from approving an NDA that relies only on its own data to support the change or innovation.

On February 27, 2014, we commenced a lawsuit against the FDA, captioned Amarin Pharmaceuticals Ireland Ltd. v. Food & Drug Administration, et al., Civ. A. No. 14-0324 (D.D.C.), that challenges FDA’s denial of our request for five-year NCE exclusivity for Vascepa based on our reading of the relevant statute, our view of FDA’s inconsistency with its past actions in this area and the retroactive effect of what we believe is a new policy at FDA as it relates to our situation. Our complaint requested that the court vacate FDA’s decision, declare that Vascepa is entitled to the benefits of five-year statutory exclusivity, bar the FDA from accepting any ANDA or similar application for which Vascepa is the reference-listed drug until after the statutory exclusivity period and set aside what we contend are—due to the denial of five-year exclusivity to Vascepa—prematurely accepted pending ANDA applications.

On May 28, 2015, the U.S. District Court for the District of Columbia granted our motion for summary judgment in this lawsuit. The decision vacated the FDA’s denial of our claim for such exclusivity and remanded to the FDA for proceedings consistent with the decision. On July 22, 2015, Watson Laboratories Inc., or Watson, the purported first Vascepa ANDA filer, sought to intervene and appeal the Court’s decision. FDA did not appeal the Court’s decision prior to the July 28, 2015 deadline for appeal and has joined in our opposition to Watson’s sought intervention and appeal. The legal process can be unpredictable, costly and time-consuming. We intend to continue to litigate the case vigorously, but cannot predict its outcome.

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*Generic company competitors are seeking approval of generic versions of Vascepa.

The Food Drug and Cosmetic Act, or FDCA, as amended by the Drug Price Competition and Patent Term Restoration Act of 1984, as amended, or the Hatch-Waxman Amendments, permit the FDA to approve abbreviated new drug applications, or ANDAs, for generic versions of brand name drugs like Vascepa. We refer to the process of generic drug applications as the “ANDA process.” The ANDA process permits competitor companies to obtain marketing approval for a drug product with the same active ingredient, dosage form, strength, route of administration, and labeling as the approved brand name drug, but without having to conduct and submit clinical studies to establish the safety and efficacy of the proposed generic product. In place of such clinical studies, an ANDA applicant needs to submit data demonstrating that its product is bioequivalent to the brand name product, usually based on pharmacokinetic studies.

The Hatch-Waxman Amendments require an applicant for a drug product that relies, in whole or in part, on the FDA’s prior approval of Vascepa, to notify us of its application, a paragraph IV notice, if the applicant is seeking to market its product prior to the expiration of the patents that claim Vascepa. A bona fide paragraph IV notice may not be given under the Hatch-Waxman Amendments until after the generic company receives from the FDA an acknowledgement letter stating that its ANDA is sufficiently complete to permit a substantive review.

The paragraph IV notice is required to contain a detailed factual and legal statement explaining the basis for the applicant’s opinion that the proposed product does not infringe our patents, that our patents are invalid, or both. After receipt of a valid notice, we would have the option of bringing a patent infringement suit in federal district court against any generic company seeking approval for its product within 45 days from the date of receipt of each notice. If such a suit is commenced within this 45 day period, we will be entitled to receive a 30 month stay on FDA’s ability to give final approval to any of the proposed products that reference Vascepa that begins on the date we receive the paragraph IV notice. The stay may be shortened or lengthened if either party fails to cooperate in the litigation and it may be terminated if the court decides the case in less than 30 months. If the litigation is resolved in favor of the applicant before the expiration of the 30 month period, the stay will be immediately lifted and the FDA’s review of the application may be completed. Such litigation is often time-consuming and costly, and may result in generic competition if such patents are not upheld or if the generic competitor is found not to infringe such patents.

We received six paragraph IV notices notifying us of submitted ANDAs to Vascepa under the Hatch-Waxman Amendments based on the FDA’s determination that we were entitled to three, and not five-year exclusivity. As a result, until recently, we have been engaged in costly litigation with the ANDA applicants to protect our patent rights.

Based on the May 28, 2015, U.S. District Court for the District of Columbia order granting our motion for summary judgment in the NCE litigation, the parties to the related Vascepa patent litigation that followed acceptance by FDA of abbreviated new drug applications, or ANDAs, to Vascepa agreed to a stay of proceeding in that patent litigation pending a new FDA determination on Vascepa exclusivity. Based on subsequent FDA notification to the ANDA filers that FDA had changed the status of their ANDAs to submitted, but no longer accepted, we believe the statutory, constructive infringement basis for the patent litigation (accepted ANDAs) no longer exists. Thus, on July 24, 2015, we moved to dismiss the pending patent infringement lawsuits against each of the Vascepa ANDA applicants. Under the terms of the parties’ agreement to stay this litigation, proceedings related to our motion to dismiss continue; the motion to dismiss is not subject to the stay. We cannot predict the outcome of this motion to dismiss or litigation. The legal process can also be costly and time-consuming. If the motion to dismiss is granted, we plan to defend the exclusivity of Vascepa through patent litigation after notification that FDA has accepted an ANDA application related to Vascepa which, assuming NCE exclusivity, we would expect no sooner than late July 2016.

If an ANDA filer is ultimately successful in patent litigation against us, it meets the requirements for a generic version of Vascepa to the satisfaction of the FDA under its ANDA (after any applicable regulatory exclusivity period and the litigation-related 30-month stay period expires), and is able to supply the product in significant commercial quantities, the generic company could introduce a generic version of Vascepa. Such a market entry would likely limit our U.S. sales, which would have an adverse impact on our business and results of operations. In addition, even if a competitor’s effort to introduce a generic product is ultimately unsuccessful, the perception that such development is in progress and/or news related to such progress could materially affect the perceived value of our company and our stock price.

In addition to the six paragraph IV notices received to date, in February 2014, prior to the FDA’s three-year exclusivity determination for Vascepa, we received a purported paragraph IV notice from a generic drug company with respect to an ANDA to Vascepa. The FDA confirmed with us after we received the notice and before the exclusivity determination was made that the FDA had not accepted for review any ANDA to Vascepa. The FDA has repeatedly taken the position that paragraph IV notices delivered to pioneer companies such as Amarin prior to the acceptance by the FDA for review of a submitted ANDA are not effective under the Hatch-Waxman Amendments. The generic company may challenge the FDA’s position on whether the notice is valid in court in connection with patent litigation. Generic companies are thought to send such premature notices to seek to avail themselves of the

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180-day generic exclusivity period for an approved product under an ANDA based on the generic’s view that it would then have first-to-file status and to seek an early end to related patent litigation with the branded drug company and the associated 30-month stay. Because we and the FDA do not believe this purported paragraph IV notice is an effective notice under the Hatch-Waxman Amendments and because FDA is not accepting ANDAs after submission at this time, we do not plan to initiate patent litigation against the generic company that submitted the ANDA until within the 45-day period after we receive a valid paragraph IV notice from such applicant.

*Vascepa is a prescription-only omega-3 fatty acid product. Omega-3 fatty acids are also marketed by other companies as non-prescription dietary supplements. As a result, Vascepa is subject to non-prescription competition and consumer substitution.

Our only current product, Vascepa, is a prescription-only omega-3 fatty acid. Mixtures of omega-3 fatty acids are naturally occurring substances contained in various foods, including fatty fish. Omega-3 fatty acids are also marketed by others as non-prescription dietary supplements. We cannot be sure physicians will view the pharmaceutical grade purity and tested safety of Vascepa as having a superior therapeutic profile to naturally occurring omega-3 fatty acids and dietary supplements. In addition, the FDA has not enforced what we view as illegal drug claims made by certain supplement manufacturers to the extent we believe appropriate under applicable law and regulations, for example, claims that such supplements reduce triglyceride levels. Also, for more than a decade now, the FDA has expressly permitted dietary supplement manufacturers that sell supplements containing the omega-3 fatty acids EPA and/or DHA to make the following qualified health claim directly to consumers: Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease. Under the preliminary ruling in our First Amendment litigation, we may now make this claim to healthcare professionals subject to certain qualifications. These factors enable dietary supplements to effectively compete with Vascepa. In addition, to the extent the net price of Vascepa after insurance and offered discounts is significantly higher than the prices of commercially available omega-3 fatty acids marketed by other companies as dietary supplements (through that lack of coverage by insurers or otherwise), physicians and pharmacists may recommend these commercial alternatives instead of writing or filling prescriptions for Vascepa or patients may elect on their own to take commercially available omega-3 fatty acids. Either of these outcomes may adversely impact our results of operations by limiting how we price our product and limiting the revenue we receive from the sale of Vascepa due to reduced market acceptance.

We may not be successful in our Vascepa co-promotion effort with Kowa Pharmaceuticals America, Inc.

In March 2014, we entered into a co-promotion agreement with Kowa Pharmaceuticals America, Inc. to co-promote Vascepa in the United States under which approximately 250 Kowa Pharmaceuticals America, Inc. sales representatives devote a substantial portion of their time to promoting Vascepa with Amarin’s approximately 130 sales representatives. Co-promotion under the agreement commenced in May 2014 based on a plan designed to substantially increase both the number of sales targets reached and the frequency of sales calls on existing sales targets. While our agreement provides for minimum performance criteria, we have little control over Kowa Pharmaceuticals America, Inc., and it may fail to devote the necessary resources and attention to promote Vascepa effectively. If that were to occur, depending on Vascepa revenues, we may have to curtail the continued development of Vascepa for approval for additional indications or increase our planned expenditures and undertake additional development or commercialization activities at our own expense. Or, we may seek to terminate the agreement and search for another commercialization partner. If we elect to increase our expenditures to fund development or commercialization activities on our own, depending on Vascepa’s revenues, we may need to obtain additional capital, which may not be available to us on acceptable terms, or at all, or which may not be possible due to our other financing arrangements. If we do not generate sufficient funds from the sale of Vascepa or, to the extent needed to supplement funds generated from product revenue, cannot raise sufficient funds, we may not be able to devote resources sufficient to market and sell Vascepa on our own in a manner required to realize the full market potential of Vascepa.

*The commercial value to us of current and sought marketing rights may be smaller than we anticipate.

There can be no assurance as to the adequacy for commercial success of the scope and breadth of the marketing rights we currently have or, if approved, an indication based on a successful outcome of the REDUCE-IT study. Even if we obtain marketing approval for additional indications, the FDA may impose restrictions on the product’s conditions for use, distribution or marketing and in some cases may impose ongoing requirements for post-market surveillance, post-approval studies or clinical trials. Also, the number of actual patients with conditions within the scope of our marketing efforts may be smaller than we anticipate. If any such marketing right or approved indication is narrower than we anticipate, the market potential for our product would suffer.

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*Our SPA agreement for ANCHOR was rescinded and our SPA agreement for REDUCE-IT is not a guarantee of FDA approval of Vascepa for the proposed REDUCE-IT indication.

A SPA is an evaluation by the FDA of a protocol with the goal of reaching an agreement that the Phase 3 trial protocol design, clinical endpoints, and statistical analyses are acceptable to support regulatory approval of the drug product candidate with respect to effectiveness for the indication studied. The ANCHOR trial was, and the REDUCE-IT trial is, being conducted under an SPA agreement with the FDA. In each case, the FDA agreed that, based on the information we submitted to the agency, the design and planned analysis of the trial is adequate to support use of the conducted study as the primary basis for approval with respect to effectiveness. A SPA agreement is generally binding upon the FDA except in limited circumstances, such as if the FDA identifies a substantial scientific issue essential to determining safety or efficacy after the study begins, or if the study sponsor fails to follow the protocol that was agreed upon with the FDA.

On October 29, 2013, the FDA notified us that it rescinded the ANCHOR study SPA agreement because the FDA determined that a substantial scientific issue essential to determining the effectiveness of Vascepa in the studied population was identified after testing began. In April 2015, we received a CRL from the FDA stating that the FDA determined not to approve label expansion reflecting the ANCHOR clinical trial efficacy data at this time.

Thus, even though we have received regulatory approval of Vascepa for the MARINE indication under an SPA agreement, our ANCHOR SPA agreement was rescinded and there is no assurance that the FDA will not rescind our REDUCE-IT SPA agreement. The inability to obtain marketing approval in the ANCHOR or REDUCE-IT indications has and would prevent us from growing revenue more significantly, and it has had, and could continue to have, a material adverse effect on our operations and financial condition, including our ability to reach profitability.

The commercial value to us of sales of Vascepa under the DCS Agreement with Eddingpharm may be smaller than we anticipate.

There can be no assurance as to the adequacy for commercial success under the DCS Agreement with Eddingpharm. Even if we and Eddingpharm obtain marketing approval in countries within the China Territory, applicable regulatory agencies may impose restrictions on the product’s conditions for use, distribution or marketing and in some cases may impose ongoing requirements for post-market surveillance, post-approval studies or clinical trials. Also, with regard to any indications for which we may gain approval in these countries, the number of actual patients with the condition included in such approved indication may be smaller than we anticipate. If any such approved indication is narrower than we anticipate, the market potential in these countries for our product would suffer.

Our products and marketing efforts are subject to extensive post-approval government regulation.

Once a product candidate receives FDA marketing approval, numerous post-approval requirements apply. Among other things, the holder of an approved NDA is subject to periodic and other monitoring and reporting obligations enforced by the FDA and other regulatory bodies, including obligations to monitor and report adverse events and instances of the failure of a product to meet the specifications in the approved application. Application holders must also submit advertising and other promotional material to regulatory authorities and report on ongoing clinical trials.

With respect to sales and marketing activities including direct-to-healthcare provider and direct-to-consumer advertising and promotional activities involving the internet, advertising and promotional materials must comply with FDA rules in addition to other applicable federal and local laws in the United States and in other countries. Our recent First Amendment ruling may cause the government to scrutinize our promotional efforts or otherwise monitor our business more closely. Industry-sponsored scientific and educational activities also must comply with FDA and other requirements. In the United States, the distribution of product samples to physicians must comply with the requirements of the U.S. Prescription Drug Marketing Act. Manufacturing facilities remain subject to FDA inspection and must continue to adhere to the FDA’s current good manufacturing practice requirements, or cGMPs. Application holders must obtain FDA approval for product and manufacturing changes, depending on the nature of the change. We also are subject to the new federal transparency requirements under the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, which require manufacturers of certain drugs, devices, biologics, and medical supplies to report to the Centers for Medicare & Medicaid Services, or CMS, information related to payments and other transfers of value to physicians and teaching hospitals and physician ownership and investment interests. We may also be subject, directly or indirectly through our customers and partners, to various fraud and abuse laws, including, without limitation, the U.S. Anti-Kickback Statute, U.S. False Claims Act, and similar state laws, which impact, among other things, our proposed sales, marketing, and scientific/educational grant programs. If we participate in the U.S. Medicaid Drug Rebate Program, the Federal Supply Schedule of the U.S. Department of Veterans Affairs, or other government drug programs, we will be subject to complex laws and regulations regarding reporting and payment obligations. We must also comply with requirements to collect and report adverse events and product complaints associated with our products. For example, in September 2014, we participated in a routine inspection from the FDA in which the FDA made observations on perceived deficiencies related to our processes for collection and processing of adverse events. We have responded to FDA with respect to these observations and continue to work with FDA to show that we have improved related systems and we

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believe that we have demonstrated to FDA that we have adequately responded to these observations. Our activities are also potentially subject to U.S. federal and state consumer protection and unfair competition laws. Similar requirements exist in many of these areas in other countries.

Depending on the circumstances, failure to meet these post-approval requirements can result in criminal prosecution, fines or other penalties, injunctions, recall or seizure of products, total or partial suspension of production, denial or withdrawal of pre-marketing product approvals, or refusal to allow us to enter into supply contracts, including government contracts. We may also be held responsible for the non-compliance of our partners, such as Kowa Pharmaceuticals America, Inc. In addition, even if we comply with FDA and other requirements, new information regarding the safety or effectiveness of a product could lead the FDA to modify or withdraw a product approval. Adverse regulatory action, whether pre- or post-approval, can potentially lead to product liability claims and increase our product liability exposure. We must also compete against other products in qualifying for coverage and reimbursement under applicable third party payment and insurance programs. In addition, all of the above factors may also apply to any regulatory approval for Vascepa obtained within the China Territory under the DCS agreement with Eddingpharm. Given our inexperience with marketing and commercializing products in the China Territory, we will need to rely on Eddingpharm to assist us in dealing with any such issues.

*The FDA and other regulatory agencies strictly regulate the promotional claims that may be made about prescription products. If we or Kowa Pharmaceuticals America, Inc. are found to have improperly promoted uses of Vascepa, we may become subject to significant fines and other liability. The government may seek to find means to prevent our promotion of truthful and non-misleading information beyond our current court ruling.

The FDA and other regulatory agencies strictly regulate the promotional claims that may be made about prescription products. In particular, in general, the U.S. government’s position has been that a product may not be promoted for uses that are not approved by the FDA as reflected in the product’s approved labeling. The government’s current position is not clear. Even though we received FDA marketing approval for Vascepa for the MARINE indication and we believe our recent First Amendment court ruling affords us a limited degree of protection for other promotional efforts, physicians may still prescribe Vascepa to their patients for use in the treatment of conditions that are not included as part of the indication statement in our FDA-approved Vascepa label or our court ruling. If we are found to have promoted Vascepa outside the terms of the court ruling or in violation of what the government may determine to be acceptable, we may become subject to significant government fines and other related liability. The government may also seek to hold us responsible for the non-compliance of our co-promotion partner, Kowa Pharmaceuticals America, Inc., or our ex-U.S. commercialization partner, Eddingpharm. For example, the Federal government has levied large civil and criminal fines against companies for alleged improper promotion and has enjoined several companies from engaging in off-label promotion. The FDA has also requested that companies enter into consent decrees or permanent injunctions under which specified promotional conduct is changed or curtailed.

In addition, incentives exist under applicable laws that encourage competitors, employees and physicians to report violations of rules governing promotional activities for pharmaceutical products. These incentives could lead to so-called whistleblower lawsuits as part of which such persons seek to collect a portion of moneys allegedly overbilled to government agencies due to, for example, promotion of pharmaceutical products beyond labeled claims. These incentives could also lead to suits that we have mischaracterized a competitor’s product in the marketplace and may, as a result, be sued for alleged damages to our competitors. Such lawsuits, whether with or without merit, are typically time-consuming and costly to defend. Such suits may also result in related shareholder lawsuits, which are also costly to defend.

Even though we have the benefit of a preliminary ruling and may be ultimately successful with a final settlement or final ruling in our current litigation related to promotion beyond FDA-approved labeling, our promotion would still be subject to a high, perhaps abnormally high, degree of scrutiny to ensure that our promotion remains within the permitted scope. Likewise, the government may seek to find other means to prevent our promotion of truthful and non-misleading information.

The REDUCE-IT cardiovascular outcomes trial may fail to show that Vascepa can reduce major cardiovascular events in an at-risk patient population on statin therapy, and the long-term clinical results of Vascepa may not be consistent with the clinical results we observed in our Phase 3 clinical trial, in which case our sales of Vascepa may then suffer.

In accordance with the SPA for our MARINE and ANCHOR trials, efficacy was evaluated in these trials compared to placebo at twelve weeks. No placebo-controlled studies have been conducted regarding the long-term effect of Vascepa on lipids, and no outcomes study has been conducted evaluating Vascepa. The REDUCE-IT study is designed to evaluate the efficacy of Vascepa in reducing major cardiovascular events in an at-risk patient population on statin therapy.

Outcomes studies of certain other lipid-modifying therapies have failed to achieve the endpoints of such studies. For example, in 2010, the results of the ACCORD-Lipid trial were published. This trial studied the effect of adding fenofibrate onto open-

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label simvastatin therapy on cardiovascular outcomes. The addition of fenofibrate did not show any treatment benefit on cardiovascular outcomes over simvastatin monotherapy in this study. In 2011, the results of the AIM-HIGH trial were published. This trial studied the effect of adding a second lipid-altering agent, extended-release niacin, to simvastatin therapy on cardiovascular outcomes in people at high risk for cardiovascular events. No significant incremental treatment benefit with extended-release niacin was observed. In addition, in September 2012, researchers published in the Journal of the American Medical Association, or JAMA, the results of a retrospective meta-analysis of twenty previously conducted studies regarding the use of omega-3 supplements across various patient populations. This meta-analysis suggested that the use of such supplements was not associated with a lower risk of all-cause death, cardiac death, sudden death, heart attack, or stroke. We believe the results of these studies may not be directly applicable to the use of Vascepa over time. For instance, the outcomes studies for fenofibrates and niacin were conducted in patient populations in which the majority of patients studied had triglycerides below 200 mg/dL and fenofibrates and niacin are believed to work differently than Vascepa in the body and do not have as favorable a side-effect profile, and nineteen of the twenty studies included in the JAMA meta-analysis involved the use of omega-3 supplements containing a mixture of EPA and DHA, and most were evaluated at relatively lower doses. In addition, in May 2013, The New England Journal of Medicine published the results of an outcome study of 1 gram per day of an omega-3 acid ethyl ester composition. In that study, the composition failed to show a benefit in reducing the rate of death from cardiovascular causes or hospitalization for cardiovascular causes when administered to patients with cardiovascular risk factors under different study conditions than in the REDUCE-IT study. Vascepa is comprised of highly-pure ethyl-EPA, and has been approved by the FDA for use in adult patients with severe hypertriglyceridemia at a dose of 4 grams per day and is being studied in REDUCE-IT at 4 grams per day.

The only other outcomes study involving the use of a highly-pure formulation of ethyl-EPA, called the Japan EPA Lipid Intervention Study (JELIS), suggested that use of a highly-pure formulation of ethyl-EPA in Japan, when used in conjunction with statins, reduced cardiovascular events by 19% compared to the use of statins alone. However, there are several limitations to the JELIS study. First, the patient population was exclusively Japanese, the majority of the participants were women, and at baseline patients had a much higher LDL, limiting its generalizability to the intended target population. Also, a low dose of statins was used. It is unknown whether the positive treatment effects would have persisted if these patients had been optimally treated with statins using contemporary LDL targets in the United States. In addition, JELIS was an open-label trial, which could influence patient and physician behavior and reporting of symptoms, decisions regarding hospitalization, and referral of events for adjudication. This may be particularly relevant since hospitalizations for unstable angina was a primary contributor of the overall positive result, and is considered a softer endpoint than fatal cardiovascular events.

Further, FDA determined that JELIS results could not be used as support for or against the use of triglyceride levels as a surrogate for cardiovascular risk reduction. Patients treated with EPA and statin in JELIS achieved triglyceride levels that were only 5% lower, on average, than those achieved among patients treated with statin alone; however, the reduction in cardiovascular risk in the primary endpoint analysis was 19%. Likewise, within the primary and secondary prevention sub-analyses, triglyceride levels were lowered only 5% on average in the EPA plus statin group compared with the statin alone group; however, the relative risk reduction was 53% in the primary prevention population with elevated triglyceride (> 150mg/dL) and low HDL-C (< 40mg/dL) levels and 23% in the secondary prevention population with established coronary artery disease. These large differences in magnitude between triglyceride reduction and risk reduction in JELIS suggest that the effects of EPA on triglyceride levels alone may not be responsible for, or predict, the observed differences in cardiovascular events between treatment groups in JELIS. JELIS was not designed to evaluate primary and secondary prevention populations. It is possible that the putative cardioprotective effects of EPA observed in JELIS are due not to a single mode of action, such as triglyceride lowering, but rather to multiple mechanisms working together, such as purported beneficial effects on multiple atherosclerosis processes, including endothelial function, oxidative stress, foam cell formation, inflammation/cytokines, plaque formation/progression, platelet aggregation, thrombus formation, and plaque rupture. The REDUCE-IT study is needed to determine the clinical benefit, if any, of EPA therapy in statin-treated patients with elevated triglyceride levels.

Although we believe the results of the JAMA meta-analysis and other studies are not directly applicable to the potential long-term clinical experience with Vascepa, there can be no assurance that the endpoints of the REDUCE-IT cardiovascular outcomes study will be achieved or that the lipid-modifying effects of Vascepa in REDUCE-IT or any other study of Vascepa will not be subject to variation beyond twelve weeks. If the REDUCE-IT trial fails to achieve its clinical endpoints or if the results of these long-term studies are not consistent with the 12-week clinical results, it could prevent us from expanding the label of any approved product or even call into question the efficacy of any approved product.

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The prospective interim efficacy and safety analysis of the REDUCE-IT cardiovascular outcomes trial may not be completed in the contemplated timeframe in 2016 and may not demonstrate to the independent committee monitoring the study a sufficient benefit risk result to warrant the independent committee recommending stopping the study early for overwhelming efficacy. The study may also be stopped for futility or for safety concerns.

In accordance with the SPA agreement for our REDUCE-IT cardiovascular outcomes trial, an interim review of the efficacy and safety results of the trial is scheduled to occur upon reaching 60% of the target aggregate number of cardiovascular events. We currently expect this interim review by the study’s independent data monitoring committee (DMC) to occur during 2016 based on our understanding of the current event rates in the study and expected future event rates. It may actually take longer to reach the targeted number of events, which would delay the DMC assessment of data for the interim analysis.

Further, as is typical of interim analyses, the statistical threshold for defining overwhelming efficacy on the primary endpoint that would call for stopping the study early in connection with such analysis is considerably higher than the threshold for defining statistical significance after the expected completion of the study in 2017. We do not expect the study to be stopped due to overwhelming efficacy at this interim look. For example, even if the appropriate studied cardiovascular events in the trial occur at sufficiently low rates in the active, Vascepa, group as compared to the placebo group such that the study would be a success at completion, the more rigorous statistical analysis applied by the DMC at the interim analysis may not warrant stoppage of the study for overwhelming efficacy in connection with the interim analysis. The study may also be stopped pursuant to recommendation by the DMC at this interim analysis for lack of signals of a favorable result at completion, so called stoppage for futility.

Moreover, it is the DMC that will make the formal recommendation as to whether to stop the study early or continue as planned. Amarin is blinded to the interim analysis and is informed by the DMC of the recommendation to stop the study or to continue as planned. The DMC may consider factors outside the pre-specified statistical analysis plan when assessing whether to continue the study as planned. For example, even if study results are sufficiently positive at the interim analysis to demonstrate overwhelming efficacy, the DMC at its discretion may recommend continuation of the study as planned with the goal of arriving at more robust results at the planned study completion if they believe that waiting for more robust results outweighs the potential medical benefit of stopping and unblinding the study early.

The DMC has multiple times per year assessed safety data generated in the ongoing study and has thus far recommended to continue the study as planned. Thus, multiple safety analyses to date have not warranted study stoppage. Nevertheless, the study may be stopped at any time based on recommendations of the DMC due to safety concerns identified by the DMC during its ongoing and regularly scheduled safety data assessments.

We may not be successful in developing or marketing future products if we cannot meet the extensive regulatory requirements of the FDA and other regulatory agencies for quality, safety and efficacy.

The success of our research and development efforts is dependent in part upon our ability, and the ability of our partners or potential partners, to meet regulatory requirements in the jurisdictions where we or our partners or potential partners ultimately intend to sell such products once approved. The development, manufacture and marketing of pharmaceutical products are subject to extensive regulation by governmental authorities in the United States, the China Territory under the DCS Agreement with Eddingpharm, the European Union, Japan and elsewhere. In the United States, the FDA generally requires pre-clinical testing and clinical trials of each drug to establish its safety and efficacy and extensive pharmaceutical development to ensure its quality before its introduction into the market. Regulatory authorities in other jurisdictions impose similar requirements. The process of obtaining regulatory approvals is lengthy and expensive and the issuance of such approvals is uncertain. The commencement and rate of completion of clinical trials and the timing of obtaining marketing approval from regulatory authorities may be delayed by many factors, including:

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Even if we obtain positive results from early stage pre-clinical or clinical trials, we may not achieve the same success in future trials. Clinical trials that we or potential partners conduct may not provide sufficient safety and efficacy data to obtain the requisite regulatory approvals for product candidates. The failure of clinical trials to demonstrate safety and efficacy for our desired indications could harm the development of that product candidate as well as other product candidates, and our business and results of operations would suffer. For example, the efficacy results of our Vascepa Phase 3 clinical trials for the treatment of Huntington’s disease were negative. As a result, we stopped development of that product candidate, revised our clinical strategy and shifted our focus to develop Vascepa for use in the treatment of cardiovascular disease.

Any approvals that are obtained may be limited in scope, may require additional post-approval studies or may require the addition of labeling statements focusing on product safety that could affect the commercial potential for our product candidates. Any of these or similar circumstances could adversely affect our ability to earn revenues from the sale of such products. Even in circumstances where products are approved by a regulatory body for sale, the regulatory or legal requirements may change over time, or new safety or efficacy information may be identified concerning a product, which may lead to the withdrawal of a product from the market or similar use restrictions. The discovery of previously unknown problems with a product or in connection with the manufacturer of products may result in restrictions on that product or manufacturer, including withdrawal of the product from the market, which would have a negative impact on our potential revenue stream.

Legislative or regulatory reform of the health care system in the United States and foreign jurisdictions may affect our ability to profitably sell Vascepa.

Our ability to commercialize our future products successfully, alone or with collaborators, will depend in part on the extent to which coverage and reimbursement for the products will be available from government and health administration authorities, private health insurers and other third-party payors. The continuing efforts of the U.S. and foreign governments, insurance companies, managed care organizations and other payors of health care services to contain or reduce health care costs may adversely affect our ability to set prices for our products which we believe are fair, and our ability to generate revenues and achieve and maintain profitability.

Specifically, in both the United States and some foreign jurisdictions, there have been a number of legislative and regulatory proposals to change the health care system in ways that could affect our ability to sell our products profitably. For example, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or collectively the PPACA, enacted in March 2010, substantially changes the way healthcare is financed by both governmental and private insurers. Among other cost-containment measures, PPACA establishes:

We expect further federal and state proposals and health care reforms to continue to be proposed by legislators, which could limit the prices that can be charged for the products we develop and may limit our commercial opportunity.

The continuing efforts of government and other third-party payors to further contain or reduce the costs of health care through various means may limit our commercial opportunity. It will be time consuming and expensive for us to go through the process of seeking coverage and reimbursement from Medicare and private payors. Our products may not be considered cost effective, and government and third-party private health insurance coverage and reimbursement may not be available to patients for any of our future products or sufficient to allow us to sell our products on a competitive and profitable basis. Our results of operations could be adversely affected by PPACA and by other health care reforms that may be enacted or adopted in the future. In addition, increasing emphasis on managed care in the United States will continue to put pressure on the pricing of pharmaceutical products. Cost control initiatives could decrease the price that we or any potential collaborators could receive for any of our future products and could adversely affect our profitability.

In some foreign countries, including major markets in the European Union and Japan, the pricing of prescription pharmaceuticals is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take 6 to 12 months or longer after the receipt of regulatory marketing approval for a product. To obtain reimbursement or pricing approval in some countries, we may be required to conduct a pharmacoeconomic study that compares the cost-effectiveness of Vascepa to other available therapies. Such pharmacoeconomic studies can be costly and the results uncertain. Our business could be harmed if reimbursement of our products is unavailable or limited in scope or amount or if pricing is set at unsatisfactory levels.

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As we evolve from a company primarily involved in research and development to a company also focused on establishing an infrastructure for commercializing Vascepa, we may encounter difficulties in managing our growth and expanding our operations successfully.

We hired and trained a professional sales force of approximately 275 sales representatives and commenced our commercial launch of Vascepa in the MARINE indication in the United States in early January 2013. The process of establishing a commercial infrastructure is difficult, expensive and time-consuming. Our October 2013 worldwide reduction in force, which included the termination of approximately 50% of the then-staffed sales force, has made this process more difficult. As our operations expand with the anticipated growth of our produce sales, we expect that we will need to manage additional relationships with various collaborative partners, suppliers and other third parties. Future growth will impose significant added responsibilities on members of management, including the need to identify, recruit, maintain and integrate additional employees. Our future financial performance and our ability to commercialize Vascepa and to compete effectively will depend, in part, on our ability to manage our future growth effectively. To that end, we must be able to manage our development efforts effectively, and hire, train, integrate and retain additional management, administrative and sales and marketing personnel. We may not be able to accomplish these tasks, and our failure to accomplish any of them could prevent us from successfully growing our company.

Risks Related to our Reliance on Third Parties

Our supply of product for commercial supply and clinical trials is dependent upon relationships with third party manufacturers and key suppliers.

We have no in-house manufacturing capacity and rely on contract manufacturers for our clinical and commercial product supply. We cannot assure you that we will successfully manufacture any product we may develop, either independently or under manufacturing arrangements, if any, with our third party manufacturers. Moreover, if any manufacturer should cease doing business with us or experience delays, shortages of supply or excessive demands on their capacity, we may not be able to obtain adequate quantities of product in a timely manner, or at all.

Any manufacturing problem, natural disaster affecting manufacturing facilities, or the loss of a contract manufacturer could be disruptive to our operations and result in lost sales. Additionally, we will be reliant on third parties to supply the raw materials needed to manufacture Vascepa. Any reliance on suppliers may involve several risks, including a potential inability to obtain critical materials and reduced control over production costs, delivery schedules, reliability and quality. Any unanticipated disruption to future contract manufacture caused by problems at suppliers could delay shipment of products, increase our cost of goods sold and result in lost sales. If our suppliers were unable to supply us with adequate volumes of active pharmaceutical ingredient (drug substance) or encapsulated bulk product (drug product), it would have a material adverse effect on our ability to continue to commercialize Vascepa.

We initially purchased all of our supply of the bulk compound (ethyl-EPA), which constitutes the only active pharmaceutical ingredient, or API, of Vascepa, from a single supplier, Nisshin Pharma, Inc., or Nisshin, located in Japan. Nisshin was approved by the FDA as a Vascepa API supplier as part of our FDA marketing approval for the MARINE indication in July 2012. In April 2013, we announced the approval by the FDA of Chemport, Inc. and BASF (formerly Equateq Limited) as additional Vascepa API suppliers. We purchase and use commercial supply from Chemport in addition to Nisshin. We terminated our agreement with BASF due to its inability to meet the agreement requirements, may enter into a new development and supply agreement with BASF, and may purchase API from BASF. In 2014, we obtained sNDA approval of a fourth supplier of API, which includes the manufacturing facility of Finorga SAS (Novasep). Each of the API manufacturers obtains supply of the key raw material to manufacture API from other third party sources of supply.

While we have contractual freedom to source the API for Vascepa and have entered into supply agreements with multiple suppliers who also rely on other third party suppliers of the key raw material to manufacture the API for Vascepa, Nisshin and Chemport currently supply all of our API for Vascepa. Our strategy in adding API suppliers beyond Nisshin has been to expand manufacturing capacity and to partially mitigate the risk of reliance on one supplier.

Expanding manufacturing capacity and qualifying such capacity is difficult and subject to numerous regulations and other operational challenges. The resources of our suppliers vary and are limited; costs associated with projected expansion and qualification can be significant. For example, Chemport, which was approved as one of our API suppliers in April 2013, is a privately-held company and their commitment to Vascepa supply has required them to seek additional resources. There can be no assurance that the expansion plans of any of our suppliers will be successful. Our aggregate capacity to produce API is dependent upon the qualification of our API suppliers. Each of our API suppliers has outlined plans for potential further capacity expansion. If no additional API supplier is approved by the FDA, our API supply will be limited to the API we purchase from previously approved suppliers. If our third party manufacturing capacity is not expanded and compliant with application regulatory requirements, we may

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not be able to supply sufficient quantities of Vascepa to meet anticipated demand. We cannot assure you that we can contract with any future manufacturer on acceptable terms or that any such alternative supplier will not require capital investment from us in order for them to meet our requirements. Alternatively, our purchase of supply may exceed actual demand for Vascepa.

We currently have encapsulation agreements with three commercial API encapsulators for the encapsulation of Vascepa: Patheon, Inc. (formerly Banner Pharmacaps), Catalent Pharma Solutions, and Capsugel US, LLC. These companies have qualified their manufacturing processes and are capable of manufacturing Vascepa. There can be no guarantee that additional other suppliers with which we have contracted to encapsulate API will be qualified to manufacture the product to our specifications or that these and any future suppliers will have the manufacturing capacity to meeting anticipated demand for Vascepa. We cannot assure you that we can contract with any future manufacturer on acceptable terms or that any such alternative supplier will not require capital investment from us in order for them to meet our requirements.

We may not be able to maintain our exclusivity with our certain third-party Vascepa suppliers if we do not meet minimum purchase obligations due to lower than anticipated sales of Vascepa.