Sorrento Therapeutics, Inc. - Quarter Report: 2014 March (Form 10-Q)

Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

For the quarterly period ended March 31, 2014

OR

For the transition period from             to            

Commission file number 001-36150

SORRENTO THERAPEUTICS, INC.

(Exact Name of Registrant as Specified in Its Charter)

6042 Cornerstone Ct. West,

Suite B

San Diego, California 92121

(Address of Principal Executive Offices)

(858) 210-3700

(Registrant’s Telephone Number, Including Area Code)

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 (§232.405 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 file 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. (Check one):

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

The number of shares of the issuer’s common stock, par value $0.0001 per share, outstanding as of May 12, 2014 was 23,053,100.

Table of Contents

Sorrento Therapeutics, Inc.

(a Development Stage Company)

Index to Consolidated Financial Statements

Table of Contents

PART I. FINANCIAL INFORMATION

SORRENTO THERAPEUTICS, INC.

(A DEVELOPMENT STAGE COMPANY)

CONSOLIDATED BALANCE SHEETS

(In thousands, except for share amounts)

See accompanying notes

1

Table of Contents

SORRENTO THERAPEUTICS, INC.

(A DEVELOPMENT STAGE COMPANY)

CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited)

(In thousands, except per share amounts)

See accompanying notes

2

Table of Contents

SORRENTO THERAPEUTICS, INC.

(A DEVELOPMENT STAGE COMPANY)

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(Unaudited)

(In thousands, except for share amounts)

See accompanying notes

3

Table of Contents

SORRENTO THERAPEUTICS, INC.

(A DEVELOPMENT STAGE COMPANY)

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

(In thousands)

See accompanying notes

4

Table of Contents

SORRENTO THERAPEUTICS, INC.

NOTES TO UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS

MARCH 31, 2014

(In thousands, except for share amounts)

1. Nature of Operations, Summary of Significant Accounting Policies and Business Activities

Nature of Operations and Basis of Presentation

Sorrento Therapeutics, Inc. (NASDAQ: SRNE), together with its wholly-owned subsidiaries (collectively, the “Company”) is a biopharmaceutical company focused on the discovery, acquisition, development and commercialization of proprietary drug therapeutics for addressing significant unmet medical needs in the U.S., Europe and additional international markets. The Company’s primary therapeutic focus is oncology, including the treatment of chronic cancer pain, but is also developing therapeutic products for other indications, including immunology and infectious diseases. The Company’s pipeline consists of its lead oncology product candidate Cynviloq™, a micellar paclitaxel formulation, resiniferatoxin (or RTX), a non-opiate, ultra potent and selective agonist of the TRPV-1 receptor for intractable pain in end-stage disease, as well as fully human therapeutic antibodies derived from our proprietary G-MAB^® library platform and antibody drug conjugates, or ADCs, and recombinant intravenous immunoglobulin, or rIVIG. In addition, the Company generates revenues from sales and services from the sale of customized reagents and providing professional services.

As of March 31, 2014, the Company had devoted substantially all of its efforts to product development, raising capital and building infrastructure, and had not realized revenues from its planned principal operations. Accordingly, the Company is considered to be in the development stage.

The accompanying interim consolidated financial statements have been prepared by the Company, without audit, in accordance with the instructions to Form 10-Q and, therefore, do not necessarily include all information and footnotes necessary for a fair statement of its financial position, results of operations and cash flows in accordance with GAAP. The accompanying consolidated financial statements include the accounts of the Company’s wholly-owned subsidiaries, IgDraSol, Inc., or IgDraSol, Sherrington Pharmaceuticals, Inc., or Sherrington, Concortis Biosystems, Corp., or Concortis, Ark Animal Therapeutics, Inc., and Sorrento Therapeutics, Inc. Hong Kong Limited, or Sorrento Hong Kong, which was registered effective December 4, 2012. Sorrento Hong Kong and Sherrington had no operating activity through March 2014. All intercompany balances and transactions have been eliminated in consolidation.

The balance sheet at December 31, 2013 is derived from the audited consolidated balance sheet at that date which is not presented herein.

In the opinion of management, the unaudited financial information for the interim periods presented reflects all adjustments, which are only normal and recurring, necessary for a fair statement of financial position, results of operations and cash flows. These consolidated financial statements should be read in conjunction with the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2013. Operating results for interim periods are not expected to be indicative of operating results for the Company’s 2014 fiscal year.

Liquidity

The Company anticipates that it will continue to incur net losses into the foreseeable future as it: (i) conducts its bioequivalence, or BE, registration trial related to Cynviloq and prepares for its New Drug Application filing anticipated in 2015, (ii) advance RTX into clinical trials and potentially pursue other human or veterinary indications, (iii) continues to identify and advance a number of potential mAb and ADC drug candidates into preclinical and clinical development activities, (iv) continues development of, and seeks regulatory approvals for, its product candidates, and begin to commercialize any approved products, and (v) expand corporate infrastructure, including the costs associated with being a NASDAQ public company.

In March 2014, the Company entered into an amended and restated loan and security agreement, increasing the September 2013 facility to $12,500 from $5,000, with the same two banks, which was funded at closing. The interest rate on the amended and restated loan is 7.95% per annum. The Company will make interest only payments on the outstanding amount of the loan on a monthly basis until October 1, 2014, after which equal monthly payments of principal and interest are due until the Term Loan maturity date of September 30, 2017. In the event the Company raises $30 million of net equity or proceeds from a collaboration, if any, the interest only period will be extended by six months. See Note 4. Management believes the Company has the ability to meet all obligations due over the course of the next twelve months.

The Company plans to continue to fund its operating losses and capital funding needs through public or private equity or debt financings, strategic collaborations, licensing arrangements, asset sales, government grants or other arrangements. The Company filed a universal shelf registration statement on Form S-3 with the Securities and Exchange Commission (“SEC”), which was declared

5

Table of Contents

effective by the SEC in July 2013. The Shelf Registration Statement provides the Company the ability to offer up to $100 million of securities, including equity and other securities as described in the registration statement. After the October 2013 underwritten offering (see Note 5), the Company has the ability to offer up to $65.4 million of additional securities. Pursuant to the Shelf Registration Statement, the Company may offer such securities from time to time and through one or more methods of distribution, subject to market conditions and the Company’s capital needs. Specific terms and prices will be determined at the time of each offering under a separate prospectus supplement, which will be filed with the SEC at the time of any offering. However, the Company cannot be sure that such additional funds will be available on reasonable terms, or at all. If the Company is unable to secure adequate additional funding, the Company may be forced to make reductions in spending, extend payment terms with suppliers, liquidate assets where possible, and/or suspend or curtail planned programs. In addition, if the Company does not meet its payment obligations to third parties as they come due, it may be subject to litigation claims. Even if the Company is successful in defending against these claims, litigation could result in substantial costs and be a distraction to management. Any of these actions could materially harm the Company’s business, results of operations, and future prospects.

If the Company raises additional funds by issuing equity securities, substantial dilution to existing stockholders would result. If the Company raises additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict the Company’s ability to operate its business.

Use of Estimates

The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Management believes that these estimates are reasonable; however, actual results may differ from these estimates.

Cash and Cash Equivalents

The Company considers all highly liquid investments purchased with original maturities of three months or less to be cash equivalents. The Company minimizes its credit risk associated with cash and cash equivalents by periodically evaluating the credit quality of its primary financial institution. The balance at times may exceed federally insured limits. The Company has not experienced any losses on such accounts.

Fair Value of Financial Instruments

The Company’s financial instruments consist of cash and cash equivalents, grants and accounts receivable, prepaid expenses and other assets, accounts payable and accrued expenses. Fair value estimates of these instruments are made at a specific point in time, based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of significant judgment and therefore cannot be determined with precision. As of March 31, 2014 and December 31, 2013, the carrying amount of cash and cash equivalents, grants and accounts receivable, prepaid expenses and other assets, accounts payable and accrued liabilities are generally considered to be representative of their respective fair values because of the short-term nature of those instruments.

Grants and Accounts Receivable

Grants receivable at March 31, 2014 and December 31, 2013 represent amounts due under several federal contracts with the National Institute of Allergy and Infectious Diseases, or NIAID, a division of the National Institutes of Health, or NIH, collectively, the NIH Grants. The Company considers the grants receivable to be fully collectible; accordingly, no allowance for doubtful amounts has been established. If amounts become uncollectible, they are charged to operations.

Accounts receivable at March 31, 2014 and December 31, 2013 consists of trade receivables from sales and services provided to certain customers, which are generally unsecured and due within 30 days. Estimated credit losses related to trade accounts receivable are recorded as general and administrative expenses and as an allowance for doubtful accounts within grants and accounts receivable, net. The Company reviews reserves and makes adjustments based on historical experience and known collectability issues and disputes. When internal collection efforts on accounts have been exhausted, the accounts are written off by reducing the allowance for doubtful accounts. As of March 31, 2014 and December 31, 2013, the allowance for doubtful accounts was $9 and $0, respectively.

Property and Equipment

Property and equipment are carried at cost less accumulated depreciation. Depreciation of property and equipment is computed using the straight-line method over the estimated useful lives of the assets, which are generally three to five years. Leasehold improvements are amortized over the lesser of the life of the lease or the life of the asset. Repairs and maintenance are charged to expense as incurred.

6

Table of Contents

Acquisitions and Intangibles

The Company has engaged in business combination activity. The accounting for business combinations requires management to make judgments and estimates of the fair value of assets acquired, including the identification and valuation of intangible assets, as well as liabilities assumed. Such judgments and estimates directly impact the amount of goodwill recognized in connection with each acquisition, as goodwill presents the excess of the purchase price of an acquired business over the fair value of its net tangible and identifiable intangible assets.

Patent rights are stated at cost and depreciated on a straight-line basis over the estimated useful lives of the assets, determined to be approximately nineteen years from the date of transfer of the rights to the Company in April 2013. Amortization expense for the three months ended March 31, 2014 and for the period from inception (January 25, 2006) (“Inception”) through March 31, 2014 was $1 and $5, respectively, which has been included in intangibles amortization.

License rights are stated at cost and depreciated on a straight-line basis over the estimated useful lives of the assets, determined to be approximately fifteen years from the date of acquisition of the rights in September 2013. Amortization expense for the three months ended March 31, 2014 and for the period from Inception through March 31, 2014 was $475 and $1,061, respectively, which has been included in intangibles amortization.

Acquired technology is stated at cost and depreciated on a straight-line basis over the estimated useful lives of the assets, determined to be approximately nineteen years from the date of acquisition of the technology in December 2013. Amortization expense for the three months ended March 31, 2014 and for the period from Inception through March 31, 2014 was $44 and $50, respectively, which has been included in intangibles amortization.

Customer relationships are stated at cost and depreciated on a straight-line basis over the estimated useful lives of the assets, determined to be approximately five years from the date of acquisition in December 2013. Amortization expense for the three months ended March 31, 2014 and for the period from Inception through March 31, 2014 was $66 and $75, respectively, which has been included in intangibles amortization.

Impairment of Long-Lived Assets

The Company evaluates its long-lived assets with definite lives, such as property and equipment, acquired technology, customer relationships, patent and license rights, for impairment by considering competition by products prescribed for the same indication, the likelihood and estimated future entry of non-generic and generic competition with the same or similar indication and other related factors. The factors that drive the estimate of the life are often uncertain and are reviewed on a periodic basis or when events occur that warrant review. Recoverability is measured by comparison of the assets’ book value to future net undiscounted cash flows that the assets are expected to generate. There have not been any impairment losses of long-lived assets through March 31, 2014.

Goodwill

Goodwill represents the excess of purchase price over fair value of net assets acquired in a business combination accounted for by the acquisition method of accounting and is not amortized, but subject to impairment testing at least annually or when a triggering event is identified that could indicate a potential impairment. We test our goodwill annually, or quarterly when events or changes in circumstances warrant, for impairment in the fourth quarter of each year. We are organized as a single reporting unit and perform impairment testing by comparing the carrying value of the reporting unit to the market value of the Company.

Revenue Recognition

The Company’s inception to date revenues are generated primarily from three NIH and two U.S. Department of Treasury (or U.S. Treasury) grant awards and a feasibility study agreement, or the Collaboration Agreement entered into with a third party in July 2010, and from revenues generated from sales and services are from the sale of customized reagents and providing professional services. The revenue from the NIH and U.S. Treasury grant awards are based upon subcontractor and internal costs incurred that are specifically covered by the grant, and where applicable, a facilities and administrative rate that provides funding for overhead expenses. These revenues are recognized when expenses have been incurred by subcontractors or when the Company incurs internal expenses that are related to the grant.

The revenue from the Collaboration Agreement was derived from the completion of certain development services and the reimbursement of certain development costs incurred to provide such development services. Revenue from upfront, nonrefundable service fees are recognized when earned, as evidenced by written acknowledgement from the collaborator, or other persuasive evidence that all service deliverables have been achieved, provided that the service deliverables are substantive and their achievability was not reasonably assured at the inception of the Collaboration Agreement. Any amounts received prior to satisfying the Company’s revenue recognition criteria are recorded as deferred revenue.

Revenues from sales and services are generated from the sale of customized reagents and providing professional services. Reagents are used for preparing ADCs, these reagents include industrial standard cytotoxins, linkers, and linker-toxins. The professional services include providing synthetic expertise to customer’s synthesis by delivering them proprietary cytotoxins, linkers and linker-toxins and ADC service using industry standard toxin and antibodies provided by customers. Revenue is recognized when (i) persuasive evidence of an arrangement exists, (ii) the product has been shipped or the services have been rendered, (iii) the price is fixed or determinable, and (iv) collectability is reasonably assured.

7

Table of Contents

The Company is obligated to accept from customers the return of products sold that are damaged or don’t meet certain specifications. The Company may authorize the return of products sold in accordance with the terms of its sales contracts, and estimates allowances for such amounts at the time of sale. The Company has not experienced any sales returns.

Acquired In-Process Research and Development Expense

The Company has acquired and may continue to acquire the rights to develop and commercialize new drug candidates. The up-front payments to acquire a new drug compound, as well as future milestone payments, are immediately expensed as acquired in-process research and development provided that the drug has not achieved regulatory approval for marketing and, absent obtaining such approval, have no alternative future use.

Research and Development Costs and Collaborations

All research and development costs are charged to expense as incurred. Such costs primarily consist of lab supplies, contract services, stock-based compensation expense, salaries and related benefits.

Income Taxes

The provisions of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 740-10, Uncertainty in Income Taxes, address the determination of whether tax benefits claimed or expected to be claimed on a tax return should be recorded in the financial statements. Under ASC 740-10, the Company may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by taxing authorities, based on the technical merits of the position. The Company has determined that it has no uncertain tax positions.

The Company accounts for income taxes using the asset and liability method to compute the differences between the tax basis of assets and liabilities and the related financial amounts, using currently enacted tax rates.

The Company has deferred tax assets, which are subject to periodic recoverability assessments. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount that more likely than not will be realized. The Company evaluates the recoverability of the deferred tax assets annually. As of March 31, 2014, the Company maintained a full valuation allowance against its deferred tax assets.

Stock-based Compensation

The Company accounts for stock-based compensation in accordance with FASB ASC Topic 718, which establishes accounting for equity instruments exchanged for employee services. Under such provisions, stock-based compensation cost is measured at the grant date, based on the calculated fair value of the award, and is recognized as an expense, under the straight-line method, over the employee’s requisite service period (generally the vesting period of the equity grant).

The Company accounts for equity instruments, including restricted stock or stock options, issued to non-employees in accordance with authoritative guidance for equity based payments to non-employees. Stock options issued to non-employees are accounted for at their estimated fair value determined using the Black-Scholes option-pricing model. The fair value of options granted to non-employees is re-measured as they vest, and the resulting increase in value, if any, is recognized as expense during the period the related services are rendered. Restricted stock issued to non-employees is accounted for at their estimated fair value as they vest.

Net Loss per Share

Net loss per share is presented as both basic and diluted net loss per share. Basic net loss per share excludes any dilutive effects of options, shares subject to repurchase and warrants. Diluted net loss per share includes the impact of potentially dilutive securities. No dilutive effect was calculated for the three months ended March 31, 2014 and 2013 as the Company reported a net loss for each respective period and the effect would have been anti-dilutive. The Company had outstanding common share equivalents of 1,820,126 and 423,800 at March 31, 2014 and 2013, respectively.

Comprehensive Income (Loss)

Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company is required to record all components of comprehensive loss in the consolidated financial statements in the period in which they are recognized. Net income (loss) and other comprehensive loss, including foreign currency translation adjustments and unrealized gains and losses on investments, are reported, net of their related tax effect, to arrive at comprehensive loss. For the three months ended March 31, 2014 and 2013, the comprehensive loss was equal to the net loss.

8

Table of Contents

New Accounting Standards

During the quarter ended March 31, 2014, there were no new accounting pronouncements or updates to recently issued accounting pronouncements disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013 that affect the Company’s results of operations, financial condition, liquidity or disclosures.

2. Significant Agreements and Contracts

License Agreement with The Scripps Research Institute

In January 2010, the Company entered into a license agreement, or the TSRI License, with The Scripps Research Institute, or TSRI. Under the TSRI License, TSRI granted the Company an exclusive, worldwide license to certain TSRI patent rights and materials based on quorum sensing for the prevention and treatment of Staphylococcus aureus (“Staph”) infections, including Methicillin-resistant Staph. In consideration for the license, the Company: (i) issued TSRI a warrant for the purchase of common stock, (ii) agreed to pay TSRI a certain annual royalty commencing in the first year after certain patent filing milestones are achieved, (iii) agreed to pay a royalty on any sales of licensed products by the Company or its affiliates and a royalty for any revenues generated by the Company through its sublicense of patent rights and materials licensed from TSRI under the TSRI License. The TSRI License requires the Company to indemnify TSRI for certain breaches of the agreement and other matters customary for license agreements. The parties may terminate the TSRI License at any time by mutual agreement. In addition, the Company may terminate the TSRI License by giving 60 days’ notice to TSRI and TSRI may terminate the TSRI License immediately in the event of certain breaches of the agreement by the Company or upon the Company’s failure to undertake certain activities in furtherance of commercial development goals. Unless terminated earlier by either or both parties, the term of the TSRI License will continue until the final expiration of all claims covered by the patent rights licensed under the agreement. For the three months ended March 31, 2014 and 2013 and for the period from inception (January 25, 2006)(“Inception”) through March 31, 2014, the Company recorded $7, $3 and $200 in patent prosecution and maintenance costs associated with the TSRI License, respectively, which have been included in general and administrative expenses.

The fair value of the warrants to purchase Company common stock, issued in connection with the TSRI License, of $18 was determined using the Black-Scholes valuation model with the following weighted-average assumptions: risk-free interest rate of 2.48%, no dividend yield, expected term of 10 years, and volatility of 102%. Such fair value has been included in general and administrative expenses for the period from Inception through March 31, 2014.

NIH Grants

In May 2010, the NIAID awarded the Company an Advanced Technology Small Business Technology Transfer Research grant to support the Company’s program to generate and develop novel antibody therapeutics and vaccines to combat Staph infections, including Methicillin-resistant Staph, or the Staph Grant award. The project period for the Staph Grant award covered a two-year period which commenced in June 2010 and ended in May 2012, with a total grant award of $600. The Company recorded revenue associated with the grant as the related costs and expenses were incurred. During the period from Inception through March 31, 2014, the Company recorded $600 of revenue associated with the Staph Grant award.

In July 2011, the NIAID awarded the Company a second Advanced Technology Small Business Technology Transfer Research grant to support the Company’s program to generate and develop antibody therapeutics and vaccines to combat C. difficile infections, or the C. difficile Grant award. The project period for the Phase I C. difficile Grant award covered a two-year period which commenced in June 2011 and ended in June 2013, with the total grant award of $600. During the three months ended March 31, 2014 and 2013 and for the period from Inception through March 31, 2014, the Company recorded $0, $77 and $593 of revenue associated with the C. difficile Grant award, respectively.

In June 2012, the NIAID awarded the Company a third Advanced Technology Small Business Technology Transfer Research grant to support the Company’s program to generate and develop novel human antibody therapeutics to combat Staph infections, including Methicillin-resistant Staph, or the Staph Grant II award. The project period for the phase I grant covers a two-year period which commenced in June 2012, with a total grant award of $600. During the three months ended March 31, 2014 and 2013 and for the period from Inception through March 31, 2014, the Company recorded $98, $57 and $535 of revenue associated with the Staph Grant II award, respectively.

3. Mergers and Acquisitions

On September 9, 2013, the Company exercised its option to acquire IgDraSol whereby IgDraSol became a wholly-owned subsidiary and the Company acquired all rights to Cynviloq. Pursuant to the merger agreement, the Company issued 3,006,641 shares of common stock to IgDraSol stockholders and paid $382 in cash. Upon the later achievement of a specified regulatory milestone, the Company will issue an additional 1,306,272 shares of common stock to former IgDraSol stockholders. The Company’s lead compound is Cynviloq, a micellar paclitaxel formulation drug product. Cynviloq is currently approved and marketed in several

9

Table of Contents

countries, including South Korea for MBC and NSCLC under the trade name Genexol-PM^®. The Company licensed exclusive distribution rights for Cynviloq in North America, the 27 countries of the European Union, and Australia, from Samyang Biopharmaceuticals Corporation, a South Korean corporation.

On October 9, 2013, the Company entered into an Agreement and Plan of Merger and Reorganization and acquired privately-held Sherrington in exchange for 200,000 shares of its common stock, for an aggregate purchase price of $1,698 which was recognized as acquired in-process research and development expense. Sherrington is focused on the development of a treatment for intractable pain in end-stage disease. RTX is a novel, non-opiate, small molecule that permanently eliminates pain experienced by end-stage cancer patients when directly interacting with the nerve cells. RTX is currently being tested in an investigator-sponsored Phase I/II clinical trial under a Cooperative Research and Development Agreement. To date, 10 patients with terminal cancer pain have been treated at the NIH. The Company intends to launch additional trials to rapidly advance clinical development of the drug in patients with terminal cancer pain.

On December 19, 2013, the Company completed its Agreement and Plan of Merger and acquired privately-held Concortis. Upon closing, the Company issued an aggregate of 1,331,978 shares of its common stock to the Concortis shareholders. Certain Concortis employees and consultants received $1,000 in compensation for the year ending December 31, 2013 and are to receive annual deferred compensation payments totaling $1,000 on December 31 for each of the years ending 2014, 2015, and 2016. The net present value of the deferred compensation payments was calculated using the effective interest method, and is included in the purchase price. The total transaction is valued at $14.7 million. Concortis, now a wholly-owned subsidiary, has proprietary cytotoxic payloads as well as C-lock^® and K-lock^® conjugation technologies that allow for site-specific toxin conjugation to the antibody. These next generation technologies may improve the overall stability and potency of the ADCs. First-generation conjugation technologies lead to inconsistent drug-antibody ratios, which result in a heterogeneous mixture of ADCs. This variability has been a constraining factor in unlocking the full therapeutic potential for current-generation ADCs. The ADC technology complements the Company’s existing development programs, particularly its G-MAB^® antibody library and related monoclonal antibodies. Concortis uses its proprietary technologies to provide various customized reagents as well as drug conjugation services to customers in the pharmaceutical industry.

The IgDraSol, Sherrington and Concortis acquisitions have been accounted for in accordance with the acquisition method of accounting under FASB ASC Topic 805, “Business Combinations” (“Topic 805”). Topic 805 requires, among other things, that identifiable assets acquired and liabilities assumed be recognized at their fair values which are based in part on third party appraisals as of the Acquisition Date. Under the acquisition method of accounting, the purchase consideration was allocated to the assets acquired, including tangible assets and other identifiable intangible assets and liabilities assumed, based on their estimated fair market values on the date of acquisition. Any excess purchase price after the initial allocation to identifiable net tangible and identifiable intangible assets was assigned to goodwill. These completed acquisitions have been accounted for as purchases and the results of operations have been included in the consolidated financial statements since their respective dates of acquisition.

The following unaudited pro forma consolidated financial information summarizes the combined results of operations for the Company as though the IgDraSol, Sherrington and Concortis acquisitions occurred as of January 1, 2013. The unaudited pro forma financial information for all periods presented also includes the business combination accounting effects resulting from these acquisitions including amortization charges from acquired intangible assets. The unaudited pro forma financial information as presented below is for informational purposes only and does not purport to be indicative of the results of operations for future periods or the results what actually would have been realized had the entities been a single entity during these periods. The unaudited pro forma combined results are presented in thousands, except share and per share information.

4. Goodwill

The acquisitions of IgDraSol, Sherrington and Concortis generated goodwill of $24,041. No impairment to the carrying value of this goodwill has been identified from Inception through March 31, 2014.

5. Loan and Security Agreement

In September 2013, the Company entered into a $5,000 loan and security agreement with two banks pursuant to which: (i) the lenders provided the Company a term loan which was funded at closing, (ii) the Company repaid its then outstanding equipment loan balance of $762, and (iii) the lenders received a warrant to purchase an aggregate 31,250 shares of the Company’s common stock at an exercise price of $8.00 per share exercisable for seven years from the date of issuance. The value of the warrants, totaling $215, was recorded as debt discount and additional paid-in capital.

10

Table of Contents

In March 2014, the Company entered into an amended and restated loan and security agreement, increasing the September 2013 facility to $12,500 from $5,000, with the same two banks. Such loan was funded at closing and is secured by a lien covering substantially all of the Company’s assets, excluding intellectual property, which is subject to a negative pledge. The Company will make interest only payments on the outstanding amount of the loan on a monthly basis until October 1, 2014, after which equal monthly payments of principal and interest are due until the loan maturity date of September 30, 2017. In the event the Company raises $30 million of net equity or proceeds from a collaboration, if any, the interest only period will be extended by six months. The amended and restated loan: (i) interest rate is 7.95% per annum, and (ii) provided the Lenders additional warrants to purchase an aggregate of 34,642 shares of the Company’s common stock at an exercise price of $12.99 per share, exercisable for seven years from the date of issuance. The value of the warrants, totaling $322, was recorded as debt discount and additional paid-in capital.

At the Company’s option, it may prepay all of the outstanding principal balance, subject to certain pre-payment fees ranging from 1% to 3% of the prepayment amount. In the event of a final payment of the loans under the loan agreement, either in the event of repayment of the loan at maturity or upon any prepayment, the Company is obligated to pay the amortized portion of the final fee of $781.

The Company is also subject to certain affirmative and negative covenants under the loan agreement, including limitations on its ability to: undergo certain change of control events; convey, sell, lease, license, transfer or otherwise dispose of any equipment financed by loans under the loan agreement; create, incur, assume, guarantee or be liable with respect to indebtedness, subject to certain exceptions; grant liens on any equipment financed under the loan agreement; and make or permit any payment on specified subordinated debt. In addition, under the loan agreement, subject to certain exceptions, the Company is required to maintain with the lender its primary operating, other deposit and securities accounts.

Long-term debt and unamortized discount balances are as follows (in thousands):

Future minimum payments under the amended and restated loan and security agreement are as follows:

6. Stockholders’ Equity

Common Stock and Related Party Transaction

Between February 2006 and March 2009 we issued 4,414,423 shares of common stock to founders in conjunction with the founding of the Company and to certain consultants for total proceeds of approximately $1.

In June 2009, the Company issued 2,360,611 shares of common stock at $0.98 per share for aggregate gross proceeds of $2,300 in a private placement transaction. Related stock issuance costs totaled $26.

In September 2009, and in connection with the Merger, the Company: (i) issued 1,785,375 shares of common stock, in a private placement transaction, at $1.12 per share for aggregate gross proceeds of $2,000, (ii) issued 442,958 shares of common stock to the former stockholders of QuikByte, and (iii) incurred costs associated with the Merger totaling $169.

11

Table of Contents

In December 2010, the Company issued 1,028,686 shares of common stock, in a private placement transaction, at $3.50 per share for aggregate gross proceeds of $3.6 million. Related stock issuance costs were estimated at $160. In 2011, the Company reduced its stock issuance costs accrued in 2010 by $80.

In December 2011, the Company entered into a Stock Purchase Agreement and issued 500,000 shares of common stock, in a private placement transaction, at $4.00 per share for aggregate gross proceeds of $2,000. In May 2012, pursuant to the Stock Purchase Agreement, as amended and restated, the Company issued 1,500,000 shares of common stock, in a private placement transaction, at $4.00 per share for aggregate gross proceeds of $6,000. Two hundred and fifty thousand of the shares were purchased by an investor, Hongye SD Group, LLC, of which Dr. Henry Ji, the Company’s Chief Executive Officer and President, is a managing director.

In January 2013, the Company entered into the assignment agreement and issued 10,000 shares of common stock valued at $40.

In March 2013, the Company entered into a Stock Purchase Agreement and issued 1,426,406 shares of common stock, in a private placement transaction, at $4.50 per share for aggregate gross proceeds of $6,418.

On October 30, 2013, the Company closed an underwritten public offering of 4,150,000 shares of common stock, at $7.25 per share, and closed the full exercise of the over-allotment option granted to the representative of the underwriters to purchase an additional 622,500 shares of its common stock, with total gross proceeds of $34.6 million, before underwriting discounts and commissions and other offering expenses payable by the Company. The common stock began trading on The NASDAQ Capital Market on October 25, 2013 under the symbol “SRNE”.

In January 2014, the Company entered into a research agreement and issued 25,000 shares of common stock valued at $209.

Purchase Warrants

Concurrent with the October 30, 2013 offering, the Company agreed to issue and sell to the underwriters a warrant (“Underwriters Warrant”) for the purchase of an aggregate of 182,600 shares of common stock, for a nominal amount. The Underwriters Warrant agreement is exercisable, in whole or in part, commencing on a date which is one (1) year after the effective date of the Registration Statement and expiring on the five-year anniversary of the effective date of the Registration Statement at an initial exercise price per share of common stock of $9.0625, which is equal to 125% of the initial public offering price of $7.25 per share.

Convertible Promissory Notes

In October 2013, the Company issued an aggregate $1,850,000 principal amount of Notes that bear interest at 7% per annum. Concurrently with the closing of the public offering, such Notes and related accrued interest totaling $7 automatically converted into 256,119 shares of common stock.

Stock Incentive Plans

2009 Equity Incentive Plan

In February 2009, prior to the Merger, the Company’s Board of Directors approved the 2009 Equity Incentive Plan, or the EIP, under which 400,000 shares of common stock were reserved for issuance to employees, non-employee directors and consultants of the Company. In March 2009, the Company issued 296,154 restricted common stock awards to certain consultants for aggregate gross proceeds of less than $1, of which the Company repurchased 44,166 unvested shares of restricted common stock for a nominal amount in January 2011. The restricted shares vest monthly over four years and all remaining shares were fully vested as of March 31, 2014. No further shares are available for grant under the EIP.

2009 Non-Employee Director Grants

In September 2009, prior to the adoption of the 2009 Stock Incentive Plan, the Company’s Board of Directors approved the reservation and issuance of 8,000 nonstatutory stock options to the Company’s non-employee directors. The outstanding options vested on the one year anniversary of the vesting commencement date in October 2010, and are exercisable for up to 10 years from the grant date. No further shares may be granted under this plan and, as of March 31, 2014, 3,200 options were outstanding.

2009 Stock Incentive Plan

In October 2009, the Company’s stockholders approved the 2009 Stock Incentive Plan. In April 2013, the Company’s stockholders approved, among other items, the amendment and restatement of the 2009 Stock Incentive Plan, or the Stock Plan, to increase the number of common stock authorized to be issued pursuant to the Stock Plan to 1,360,000. Such shares of the Company’s common stock are reserved for issuance to employees, non-employee directors and consultants of the Company. In addition, this amount will be automatically increased annually on the first day of each fiscal year by the lesser of: (i) 1% of the aggregate number of shares of the Company’s common stock outstanding on the last day of the immediately preceding fiscal year, (ii) 200,000 shares, or

12

Table of Contents

(iii) an amount approved by the administrator of the Stock Plan. The Stock Plan provides for the grant of incentive stock options, non-incentive stock options, stock appreciation rights, restricted stock awards, unrestricted stock awards, restricted stock unit awards and performance awards to eligible recipients. Recipients of stock options shall be eligible to purchase shares of the Company’s common stock at an exercise price equal to no less than the estimated fair market value of such stock on the date of grant. The maximum term of options granted under the Stock Plan is ten years. Employee option grants will generally vest 25% on each anniversary of the original vesting date over four years. The vesting schedules for grants to non-employee directors and consultants will be determined by the Company’s Compensation Committee. Stock options are generally not exercisable prior to the applicable vesting date, unless otherwise accelerated under the terms of the applicable stock plan agreement. Unvested shares of the Company’s common stock issued in connection with an early exercise however, may be repurchased by the Company upon termination of the optionee’s service with the Company.

During the three months ended March 31, 2014 and 2013, the Company’s Board of Directors awarded 536,000 and 2,000 options to certain employees and consultants. As of March 31, 2014 and 2013, 70,066 and 499,700 shares were available for grant under the Stock Plan, respectively.

The Company uses the Black-Scholes valuation model to calculate the fair value of stock options. Stock based compensation expense is recognized over the vesting period using the straight-line method. The fair value of employee stock options was estimated at the grant date using the following assumptions:

The weighted average grant date fair value per share of employee stock options granted during the three months ended March 31, 2014 and 2013 was $11.70 and $5.00, respectively.

The assumed dividend yield was based on the Company’s expectation of not paying dividends in the foreseeable future. Due to the Company’s limited historical data, the estimated volatility incorporates the historical and implied volatility of comparable companies whose share prices are publicly available. The risk-free interest rate assumption was based on the United States Treasury’s rates for U.S. Treasury zero-coupon bonds with maturities similar to those of the expected term of the award being valued. The weighted average expected life of options was estimated using the average of the contractual term and the weighted average vesting term of the options.

The total employee stock-based compensation recorded as operating expenses was $1,844, $143 and $3,808 for the three months ended March 31, 2014 and 2013 and for the period from Inception through March 31, 2014, respectively.

As of March 31, 2014, unrecognized compensation cost related to the options was $6,321 which will be recognized over 3.4 years.

The Company records equity instruments issued to non-employees as expense at their fair value over the related service period as determined in accordance with the applicable authoritative guidance and periodically revalues the equity instruments as they vest. Stock-based compensation expense related to non-employee consultants recorded as operating expenses was $59, $104 and $1,351 for the three months ended March 31, 2014 and 2013 and for the period from Inception through March 31, 2014, respectively.

7. Income Taxes

The Company maintains deferred tax assets that reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. These deferred tax assets include net operating loss carryforwards, research credits and capitalized research and development. The net deferred tax asset has been fully offset by a valuation allowance because of the Company’s history of losses. Utilization of operating losses and credits may be subject to substantial annual limitation due to ownership change provisions of the Internal Revenue Code of 1986, as amended, and similar state provisions. The annual limitation may result in the expiration of net operating losses and credits before utilization.

13

Table of Contents

This Quarterly Report on Form 10-Q contains “forward-looking statements” about our expectations, beliefs or intentions regarding our potential product offerings, business, financial condition, results of operations, strategies or prospects. You can identify forward-looking statements by the fact that these statements do not relate strictly to historical or current matters. Rather, forward-looking statements relate to anticipated or expected events, activities, trends or results as of the date they are made and are often identified by the use of words such as “assumes,” “plans,” “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” or “will,” and similar expressions or variations. Because forward-looking statements relate to matters that have not yet occurred, these statements are inherently subject to risks and uncertainties that could cause our actual results to differ materially from any future results expressed or implied by the forward-looking statements. Many factors could cause our actual activities or results to differ materially from the activities and results anticipated in forward-looking statements. These factors include those described under the caption “Risk Factors” included elsewhere in this Quarterly Report on Form 10-Q and in our other filings with the Securities and Exchange Commission, or the SEC. Furthermore, such forward-looking statements speak only as of the date of this report. We undertake no obligation to update any forward-looking statements to reflect events or circumstances occurring after the date of such statements.

Overview

We are a development stage biopharmaceutical company engaged in the discovery, acquisition, development and commercialization of proprietary drug therapeutics for addressing significant unmet medical needs in the U.S., Europe and additional international markets. Our primary therapeutic focus is oncology, including the treatment of chronic cancer pain, but we are also developing therapeutic products for other indications, including immunology and infectious diseases. We currently have two clinical development programs underway: (i) our lead oncology drug product candidate Cynviloq, is a micellar diblock copolymeric paclitaxel formulation, and (ii) RTX, a non-opiate, ultra potent and selective agonist of the TRPV-1 receptor for intractable pain in end-stage disease.

Our pipeline also includes preclinical fully human therapeutic antibodies, including our fully human anti-PD-L1 and anti-PD-1 monoclonal antibodies, or Abs, derived from our proprietary G-MAB^® library platform, antibody drug conjugates, or ADCs, and recombinant intravenous immunoglobulin, or rIVIG. Our objective is to develop two classes of antibody drug products, therapeutic antibodies and ADCs: (i) FIC, and/or (ii) BIC, which may offer greater efficacy and/or fewer adverse events or side effects as compared to existing drugs.

Through March 31, 2014, we identified and further developed a number of potential drug product candidates across various therapeutic areas, and intend to select several lead product candidates to further advance into preclinical development activities in 2014. It is too early to assess which of these candidates, if any, will merit further evaluation in clinical trials. Our libraries were designed to facilitate the rapid identification and isolation of highly specific, antibody therapeutic product candidates that are fully-human and that bind to disease targets appropriate for antibody therapy. We built our initial antibody expression and production capabilities to enable us to make sufficient product material to conduct preclinical safety and efficacy testing in animal models.

Although we intend to retain ownership and control of some product candidates by advancing the development, we will also consider partnerships with pharmaceutical or biopharmaceutical companies in order to balance the risks associated with drug discovery and development and maximize our stockholders’ returns. Our partnering objectives include generating revenue through license fees, milestone-related development fees and royalties by licensing rights to our product candidates.

Recent Developments

Loan and Security Agreement. In March 2014, we entered into an amended and restated loan and security agreement, increasing the September 2013 facility from $5,000 to $12,500, with two banks. The amended and restated loan was funded in March 2014, is secured by a lien covering substantially all of the Company’s assets, excluding intellectual property, which is subject to a negative pledge, and bears interest at 7.95% per annum. We will make interest only payments on the outstanding amount of the loan on a monthly basis until October 1, 2014, after which equal monthly payments of principal and interest are due until the loan maturity date of September 30, 2017. In the event we raise $30 million of net equity or proceeds from a collaboration, if any, the interest only period will be extended by six months. The amended and restated loan provided the Lenders additional warrants to purchase an aggregate of 34,642 shares of the Company’s common stock at an exercise price of $12.99 per share, exercisable for seven years from the date of issuance. The value of the warrants, totaling $322, was recorded as debt discount and additional paid-in capital.

Agreement and Plan of Merger with IgDraSol. On March 7, 2013, we entered into various agreements with IgDraSol, a private company focused on the development of Cynviloq, as follows: (i) an exclusive option agreement, (ii) an asset purchase agreement pursuant to which we agreed to purchase all documentation, equipment, information and other know-how related to micellar nanoparticle technology encompassing Tocosol^® and related technologies, and (iii) an initial services agreement, pursuant to which, IgDraSol provided certain product development and technology services related to our antibody platform. On September 9, 2013, we exercised our option to acquire IgDraSol and IgDraSol became a wholly-owned subsidiary.

14

Table of Contents

On July 29, 2013, we received official meeting minutes from an End-of-Phase II meeting held on July 23, 2013 for Cynviloq (or IG-001) with the U.S. Food and Drug Administration, or FDA. Cynviloq is initially under development for the treatment of MBC and NSCLC, in the U.S. The FDA Division of Oncology Products 1 agreed that the data available from: (i) the postmarketing surveillance studies conducted in ex-U.S. territories for MBC and NSCLC, (ii) Phase I-III studies for MBC, and (iii) Phase I-II studies in NSCLC, Ovarian, Bladder, and Pancreatic cancers are sufficient to support pursuing the 505(b)(2) Bioequivalence (BE) regulatory submission pathway approach using Abraxane^® and Taxol^® as the Reference Listed Drugs. Abraxane is an albumin-bound paclitaxel (nab-paclitaxel) product approved for MBC, NSCLC and pancreatic cancer indications. Taxol is a cremophor-based paclitaxel product approved for these indications as well as other cancer indications. We filed our BE protocol in 2013 and commenced the BE study in March 2014.

Agreement and Plan of Merger with Sherrington. On October 9, 2013, we acquired Sherrington for an aggregate of 200,000 shares of our common stock. Sherrington’s sole asset was the license rights to resiniferatoxin. Upon acquisition, Sherrington became a wholly-owned subsidiary.

Underwritten Public Offering and Nasdaq Uplisting. In October 2013, we closed an underwritten public offering of 4,150,000 shares, at $7.25 per share, and closed the full exercise of the over-allotment option granted to the representative of the underwriters to purchase an additional 622,500 shares of its common stock, with total gross proceeds of $34.6 million, before underwriting discounts and commissions and other offering expenses payable by us. The common stock began trading on The NASDAQ Capital Market on October 25, 2013 under the symbol “SRNE”.

Agreement and Plan of Merger with Concortis. On December 19, 2013, we completed our previously announced merger with Concortis, which providing us with a comprehensive technology platform to create a new generation of homogenous ADC’s with site-specific toxin conjugation and consistent drug-antibody ratios. We issued 1,331,978 shares of our common stock to Concortis shareholders which were valued at $8.48 per share, the closing price per share of our common stock as of December 18, 2013.

Critical Accounting Policies and Estimates

Management’s discussion and analysis of our financial condition and results of operations are based upon our consolidated financial statements which are prepared in accordance with GAAP. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets and liabilities, related disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. We continually evaluate our estimates and judgments, the most critical of which are those related to income taxes and stock-based compensation. We base our estimates and judgments on historical experience and other factors that we believe to be reasonable under the circumstances. Materially different results can occur as circumstances change and additional information becomes known.

During the quarter ended March 31, 2014, there were no significant changes to the items that we disclosed as our critical accounting policies and estimates in Note 2 to our consolidated financial statements for the year ended December 31, 2013 contained in our 2013 Form 10-K, as filed with the SEC.

Results of Operations

The following describes certain line items set forth in our statements of operations.

Three Months Ended March 31, 2014 Compared to the Three Months Ended March 31, 2013

Revenues. Revenues were $976 for the three months ended March 31, 2014, as compared to $134 for the three months ended March 31, 2013. The net increase of $842 is primarily due to sales and service revenues of $878 generated from the sale of customized reagents and providing professional services from the Concortis operations that was acquired in December 2013. Activities under the two active grants received from the National Institute of Allergy and Infectious Diseases, a division of the National Institutes of Health, or NIH, for the three months ended March 31, 2014 were lower than in the corresponding period of 2013 due primarily to only one active grant in the quarter ending March 31, 2014 as compared to two active grants in quarter ending March 31, 2013.

In May 2010, we were awarded an Advanced Technology Small Business Technology Transfer Research grant to support our program to generate and develop novel antibody therapeutics and vaccines to combat Staph infections, including Methicillin-resistant Staph, or the Staph Grant award. The project period for the Phase 1 Staph Grant award covered a two-year period which commenced in June 2010 and ended in May 2012, with a total grant award of $600. We recorded revenue associated with the grant as the related costs and expenses were incurred. During the period from Inception through March 31, 2014, we recorded $600 of revenue associated with the Staph Grant award.

15

Table of Contents

In July 2011, we were awarded a second Advanced Technology Small Business Technology Transfer Research grant to support our program to generate and develop antibody therapeutics and vaccines to combat C. difficile infections, or the C. difficile Grant award. The project period for the C. difficile Grant award covers a two-year period which commenced in June 2011 and ended in June 2013, with a total grant award of $600. The C. difficile Grant award revenues for the three months ended March 31, 2014 and 2013 and for the period from Inception through March 31, 2014 were $0, $77 and $593, respectively.

In June 2012, we were awarded a third Advanced Technology Small Business Technology Transfer Research grant to support our program to generate and develop novel human antibody therapeutics to combat Staph infections, including Methicillin-resistant Staph, or the Staph Grant II award. The project period for the phase I grant covers a two-year period which commenced in June 2012, with a total grant award of $600. The Staph Grant II award revenues for the three months ended March 31, 2014 and 2013, and for the period from Inception through March 31, 2014, were $98, $57 and $535, respectively.

We had no other revenue during the three months ended March 31, 2014 and 2013 as we have not yet developed any product candidates for commercialization or earned any licensing or royalty payments.

We expect that any revenue we generate will fluctuate from quarter to quarter as a result of the unpredictability of the demand for products and services offered as well as the timing and amount of grant awards, research and development reimbursements and other payments received under any strategic collaborations, if any.

Cost of revenues. Cost of revenues for the three months ended March 31, 2014 were $563 and relate to the sale of customized reagents and providing professional services. The costs generally include employee-related expenses including salary and benefits, direct materials and overhead costs including rent, depreciation, utilities, facility maintenance and insurance.

Research and Development Expenses. Research and development expenses for the three months ended March 31, 2014 and 2013 were $6,107 and $1,398, respectively. Research and development expenses include the costs to identify, isolate and advance human antibody drug candidates derived from our libraries, costs to initiate and/or conduct our bioequivalence, or BE, registration trial related to Cynviloq and prepare for our New Drug Application filing anticipated in 2015, preclinical testing expenses and the expenses associated with fulfilling our development obligations related to the NIH grant awards, collectively the NIH Grants. Such expenses consist primarily of salaries and personnel related expenses, stock-based compensation expense, clinical development expenses, preclinical testing, lab supplies, consulting costs, depreciation and other expenses. The increase of $4,709 is primarily attributable to salaries and compensation related expense, preclinical testing, depreciation, consulting and lab supply costs incurred in connection with our expanded research and development activities and our BE registration trial. We expect research and development expenses to increase in absolute dollars as we: (i) advance our Cynviloq BE registration trial (a single bioequivalence study) and pursue other potential indications, including expenses incurred under agreements with CROs and investigative sites that conduct our clinical trials, the cost of acquiring, developing and manufacturing clinical trial materials, and other regulatory operating activities, (ii) incur incremental expenses associated with our efforts to further advance a number of potential drug candidates into preclinical development activities, (iii) continue to identify and advance a number of fully human therapeutic antibody and ADC preclinical drug candidates, (iv) incur higher salary, lab supply and infrastructure costs incurred in connection with supporting all of the Company’s programs.

Acquired In-process Research and Development Expenses. Acquired in-process research and development expenses for the three months ended March 31, 2014 and 2013 were $209 and $0, respectively. Acquired in-process research and development expenses include the costs associated with a research agreement.

General and Administrative Expenses. General and administrative expenses for the three months ended March 31, 2014 and 2013 were $3,385 and $1,250, respectively. General and administrative expenses consist primarily of salaries and personnel related expenses for executive, finance and administrative personnel, stock-based compensation expense, professional fees, infrastructure expenses, legal and accounting expenses and other general corporate expenses. The increase of $2,135 is primarily attributable to higher salaries and related compensation expenses, stock-based compensation, legal costs related general corporate and IP matters, consulting and business development expenses and higher compliance costs associated with our public reporting obligations. We expect general and administrative expenses to increase in absolute dollars as we: (i) incur incremental expenses associated with expanded operations and development efforts, compliance with our public reporting obligations, (ii) assume all of the ongoing operating costs associated with the mergers of IgDraSol, Sherrington and Concortis, and integrate their operations.

Intangible Amortization. Intangible amortization for the three months ended March 31, 2014 and 2013 was $586 and $0, respectively. The increase resulted primarily from the acquisition and amortization of intangible license rights from IgDraSol and from acquired technology and customer relationships from Concortis.

Interest Expense. Interest expense for the three months ended March 31, 2014 and 2013 was $223 and $10, respectively. The increase in interest expense resulted from borrowings under the loan and security agreement entered into in September 2013.

16

Table of Contents

Interest Income. Interest income for the three months ended March 31, 2014 and 2013 was $4 and $2, respectively. The increase in interest income resulted from higher average cash balances in 2014 as compared to the same period in 2013. We expect that continued low interest rates will significantly limit our interest income in the near term.

Net Loss. Net loss for the three months ended March 31, 2014 and 2013 was $10,093 and $2,522, respectively. The increase in net loss is mainly attributable to the expanded research and development, in-process research and development, intangible amortization and general and administrative activities.

Liquidity and Capital Resources

As of March 31, 2014, we had $29,949 in cash and cash equivalents primarily attributable to: (i) the closing of our underwritten public offering in October 2013, (ii) the issuance of $1,850 of convertible promissory notes, which automatically converted into 256,119 shares of our common stock upon the closing of the underwritten public offering, and (iii) net borrowings under our $12,500 amended and restated loan and security agreement which was fully funded as of March 31, 2014.

Cash Flows from Operating Activities. Net cash used for operating activities was $9,124 for 2014 and is primarily attributable to our net loss of $10,093 and our net reduction in working capital balances of $2,015, which were partially offset by $2,984 in non-cash activities relating to stock-based compensation, acquired in-process research and development, depreciation and amortization expense and other non-cash activities. Net cash used for operating activities was $2,482 for 2013 and primarily reflects a net loss of $2,522, which was partially offset by $356 in non-cash activities relating primarily to stock-based compensation and depreciation expense.

We expect to continue to incur substantial and increasing losses and have negative net cash flows from operating activities as we seek to expand and support our clinical and preclinical development and research activities.

Cash Flows from Investing Activities. Net cash used for investing activities was $94 for 2014 as compared to $207 for 2013. The net cash used related primarily to equipment acquired for research and development activities.

We expect to increase our investment in equipment as we seek to expand and progress our research and development capabilities.

Cash Flows from Financing Activities. Net cash provided by financing activities for 2014 and 2013 was $7,500 and $7,237, respectively, which were primarily derived from cash provided by increases in net borrowings under our amended and restated loan and security agreement in the quarter ended March 31, 2014 and from proceeds received from equity and equipment debt financings in the quarter ended March 31, 2013.

Future Liquidity Needs. From inception through March 31, 2014, we have principally financed our operations through an underwritten public offering and private equity financings with aggregate net proceeds of $53,153, as we have not generated any product related revenue from operations to date, and do not expect to generate significant revenue for several years, if ever. We will need to raise additional capital before we exhaust our current cash resources in order to continue to fund our research and development, including our plans for clinical and preclinical trials and new product development, as well as to fund operations generally. As and if necessary, we will seek to raise additional funds through various potential sources, such as equity and debt financings, or through corporate collaboration and license agreements. We can give no assurances that we will be able to secure such additional sources of funds to support our operations, or, if such funds are available to us, that such additional financing will be sufficient to meet our needs.

In March 2014, we entered into an amended and restated loan and security agreement, increasing the September 2013 facility from $5,000 to $12,500, with two banks. The amended and restated loan was funded in March 2014, and bears interest at 7.95% per annum. We will make interest only payments on the outstanding amount of the loan on a monthly basis until October 1, 2014, after which equal monthly payments of principal and interest are due until the loan maturity date of September 30, 2017. In the event we raise $30 million of net equity or proceeds from a collaboration, if any, the interest only period will be extended by six months.

We anticipate that we will continue to incur net losses into the foreseeable future as we: (i) conduct our BE registration trial related to Cynviloq and prepare for our New Drug Application filing anticipated in 2015, (ii) advance RTX into clinical trials and potentially pursue other human or veterinary indications, (iii) continue to identify and advance a number of potential mAb and ADC drug candidates into preclinical and clinical development activities, (iv) continue our development of, and seek regulatory approvals for, our product candidates, and begin to commercialize any approved products, and (v) expand our corporate infrastructure, including the costs associated with being a NASDAQ public company. We believe we have the ability to meet all obligations due over the course of the next twelve months.

We plan to continue to fund our losses from operations and capital funding needs through public or private equity or debt financings, strategic collaborations, licensing arrangements, asset sales, government grants or other arrangements. We filed a universal shelf registration statement on Form S-3 with the Securities and Exchange Commission (“SEC”), which was declared effective by the SEC in July 2013. The Shelf Registration Statement provides us with the ability to offer up to $100 million of securities, including

17

Table of Contents

equity and other securities as described in the registration statement. After the October 2013 underwritten offering, we now have the ability to offer up to $65.4 million of additional securities. Pursuant to the Shelf Registration Statement, we may offer such securities from time to time and through one or more methods of distribution, subject to market conditions and our capital needs. Specific terms and prices will be determined at the time of each offering under a separate prospectus supplement, which will be filed with the SEC at the time of any offering. However, we cannot be sure that such additional funds will be available on reasonable terms, or at all. If we are unable to secure adequate additional funding, we may be forced to make reductions in spending, extend payment terms with suppliers, liquidate assets where possible, and/or suspend or curtail planned programs. In addition, if we do not meet our payment obligations to third parties as they come due, we may be subject to litigation claims. Even if we are successful in defending against these claims, litigation could result in substantial costs and be a distraction to management. Any of these actions could materially harm our business, results of operations, and future prospects.

If we raise additional funds by issuing equity securities, substantial dilution to existing stockholders would result. If we raise additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict our ability to operate our business.

Off-Balance Sheet Arrangements

Since our inception through March 31, 2014, we have not engaged in any off-balance sheet arrangements as defined in Item 303(a)(4) of Regulation S-K.

New Accounting Pronouncements

Refer to Note 1, “Nature of Operations, Summary of Significant Accounting Polices and Business Activities,” in the accompanying notes to the consolidated financial statements for a discussion of recent accounting pronouncements.

As a smaller reporting company, as defined by Section 10(f)(1) of Regulation S-K, we are not required to provide the information set forth in this Item.

Conclusion Regarding the Effectiveness of Disclosure Controls and Procedures

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in our reports filed under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s regulations, rules and forms and that such information is accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate, to allow for timely decisions regarding required disclosure.

In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and management is required to apply its judgment in evaluating the cost-benefit relationship of possible controls and procedures. As required by Rule 13a-15(b) promulgated by the SEC under the Exchange Act, we carried out an evaluation, under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, of the effectiveness of the design and operation of our disclosure controls and procedures as of the end of the period covered by this Quarterly Report on Form 10-Q. Based on the foregoing, our principal executive officer and principal financial officer concluded that our disclosure controls and procedures were effective as of the end of the period covered by this Quarterly Report on Form 10-Q.

Changes in Internal Control Over Financial Reporting

There has been no change in our internal control over financial reporting during the quarter ended March 31, 2014 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

18

Table of Contents

PART II. OTHER INFORMATION

To the best of our knowledge, we are not a party to any legal proceedings that, individually or in the aggregate, are deemed to be material to our financial condition or results of operations.

Our Annual Report on Form 10-K for the year ended December 31, 2013, Part I –Item 1A, Risk Factors, describes important risk factors that could cause our business, financial condition, results of operations and growth prospects to differ materially from those indicated or suggested by forward-looking statements made in this Form 10-Q or presented elsewhere by management from time to time. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial may also materially and adversely affect our business.

There have been no material changes in our risk factors since the filing of our Annual Report on Form 10-K for the year ended December 31, 2013.

None.

None.

None.

None.

The exhibits listed in the Exhibit Index immediately preceding the exhibits are filed as part of this Quarterly Report on Form 10-Q and such Exhibit Index is incorporated herein by reference.

19

Table of Contents

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

20

Table of Contents

EXHIBIT INDEX

21