Viracta Therapeutics, Inc. - Quarter Report: 2016 March (Form 10-Q)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

(Mark One)

For the quarterly period ended March 31, 2016

OR

For the transition period from              to             

Commission file number: 000-51531

SUNESIS PHARMACEUTICALS, INC.

(Exact Name of Registrant as Specified in its Charter)

395 Oyster Point Boulevard, Suite 400

South San Francisco, California 94080

(Address of Principal Executive Offices including Zip Code)

(650) 266-3500

(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 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 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. (Check one):

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

The registrant had 86,934,956 shares of common stock, $0.0001 par value per share, outstanding as of April 30, 2016.

SUNESIS PHARMACEUTICALS, INC.

TABLE OF CONTENTS

PART I — FINANCIAL INFORMATION

SUNESIS PHARMACEUTICALS, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

(In thousands)

See accompanying notes to condensed consolidated financial statements.

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SUNESIS PHARMACEUTICALS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(In thousands, except per share amounts)

See accompanying notes to condensed consolidated financial statements.

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SUNESIS PHARMACEUTICALS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)

See accompanying notes to condensed consolidated financial statements.

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SUNESIS PHARMACEUTICALS, INC.

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

MARCH 31, 2016

(Unaudited)

1. Company Overview

Description of Business

Sunesis Pharmaceuticals, Inc. (the “Company” or “Sunesis”) was incorporated in the state of Delaware on February 10, 1998, and its facilities are located in South San Francisco, California. Sunesis is a biopharmaceutical company focused on the development and commercialization of new oncology therapeutics for the treatment of solid and hematologic cancers. The Company’s primary activities since incorporation have been conducting research and development internally and through corporate collaborators, in-licensing and out-licensing pharmaceutical compounds and technology, conducting clinical trials and raising capital.

Our most advanced program is QINPREZO^TM (vosaroxin), our product candidate for the potential treatment of acute myeloid leukemia, or AML. In October 2014, we announced the results of a Phase 3, multi-national, randomized, double-blind, placebo-controlled trial of vosaroxin in combination with cytarabine in patients with relapsed or refractory AML, or the VALOR trial. The VALOR trial did not meet its primary endpoint of demonstrating a statistically significant improvement in overall survival, but based upon the favorable results of other predefined analyses of the data, the Company submitted a letter of intent to the European Medicines Agency, or EMA, in November 2014 describing its intention to file a marketing authorization application, or MAA, for marketing authorization of vosaroxin plus cytarabine for the treatment of relapsed or refractory AML. In June 2015, the Company met separately with our Rapporteur and Co-Rapporteur, who are two appointed members of the EMA’s Committee of Human Medicinal Products. Based upon feedback from these meetings, the Company filed an MAA with the EMA at the end of 2015. In July 2015, the Company met with the U.S. Food and Drug Administration, or FDA, to discuss a potential regulatory filing in the U.S. Based upon the meeting, the FDA recommended that the Company provide additional clinical evidence prior to any regulatory filing in the U.S. As a result, the Company is evaluating regulatory and clinical strategies with the goal of gaining future marketing approval in the U.S.

In January 2014, we announced the expansion of our oncology pipeline through separate global licensing agreements for two preclinical kinase inhibitor programs. The first agreement, with Biogen Idec MA, Inc., or Biogen, is for global commercial rights to SNS-062, a selective non-covalently binding oral inhibitor of BTK. We filed a Clinical Trial Authorization, or CTA, application with the EMA in the first quarter of 2016 and enrolled the first patients in a Phase 1A study of SNS-062 in healthy volunteers.

The second agreement, with Milennium Pharmaceuticals, Inc., a wholly-owned subsidiary of Takeda Pharmaceutical Company Limited, or Takeda, is for global commercial rights to several potential first-in class, pre-clinical inhibitors of the novel target PDK1. In 2014, we selected two PDK1 inhibitors, SNS-229 and SNS-510, of which we have taken one, SNS-229 into IND-enabling absorption, distribution, metabolism and excretion, or ADME, and safety studies.

In addition, we are in a collaboration with Takeda for the development of TAK-580 (formerly MLN2480), an oral pan-RAF inhibitor, for which Takeda recently initiated a multi-arm, open-label Phase 1B study in combination with MLN0128, an oral mTORC 1/2 inhibitor; alisertib, an oral aurora A kinase inhibitor; or paclitaxel, in adult patients with advanced non-hematologic malignancies.

Significant Risks and Uncertainties

The Company has incurred significant losses and negative cash flows from operations since its inception, and as of March 31, 2016, had cash, cash equivalents and marketable securities totaling $40.0 million and an accumulated deficit of $569.5 million.

The Company will need to raise substantial additional capital to pursue a regulatory strategy for the potential commercialization of QINPREZO^TM (vosaroxin), its product candidate for the potential treatment of acute myeloid leukemia, and to continue the development of vosaroxin and the Company’s other programs. The Company expects to finance its future cash needs primarily through equity issuances, debt arrangements, one or more possible licenses, collaborations or other similar arrangements with respect to development and/or commercialization rights to vosaroxin and its other development programs, or a combination of the above. However, the Company does not know whether additional funding will be available on acceptable terms, or at all. If the Company is unable to raise required funding on acceptable terms or at all, it will need to reduce operating expenses, enter into a collaboration or other similar arrangement with respect to development and/or commercialization rights to vosaroxin, outlicense intellectual property rights to vosaroxin or our other development programs, sell unsecured assets, or a combination of the above, or be forced to delay or reduce the scope of its vosaroxin development program, potentially including any regulatory filings related to the VALOR trial, and/or limit or cease its operations.

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Concentrations of Credit Risk

In accordance with its investment policy, the Company invests cash that is not currently being used for operational purposes. The policy allows for the purchase of low risk debt securities issued by: (a) the United States and certain European governments and government agencies, and (b) highly rated banks and corporations, denominated in U.S. dollars, Euros or British pounds, subject to certain concentration limits. The policy limits maturities of securities purchased to no longer than 24 months and the weighted average maturity of the portfolio to 12 months. Management believes these guidelines ensure both the safety and liquidity of any investment portfolio the Company may hold.

Financial instruments that potentially subject the Company to concentrations of credit risk generally consist of cash, cash equivalents and marketable securities. The Company is exposed to credit risk in the event of default by the institutions holding its cash, cash equivalents and any marketable securities to the extent of the amounts recorded in the balance sheets.

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. The financial statements include all adjustments (consisting only of normal recurring adjustments) that management believes are necessary for a fair presentation of the periods presented. The balance sheet as of December 31, 2015 was derived from the audited financial statements as of that date. These interim financial results are not necessarily indicative of results to be expected for the full year or any other period. These unaudited condensed consolidated financial statements and the notes accompanying them should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2015.

During the first three months of fiscal 2016, the Company adopted Accounting Standards Update (ASU) 2016-06 “Derivatives and Hedging (Topic 815):  Contingent Put and Call Options in Debt Instruments (a consensus of the FASB Emerging Issues Task Force)”on a modified retrospective basis.  Pursuant to ASU 2016-06, a four-step decision sequence is required to assess whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts.  The economic characteristics and risks of embedded derivatives that are not clearly and closed related to their debt hosts is a criteria pursuant to Topic 815 that requires embedded derivatives be separated from the host contract and accounted for separately as derivatives.  There have been no adjustments to existing debt instruments as of the beginning of fiscal 2016 and no significant changes in our reported financial position or results of operations and cash flows as a result of the adoption of ASU 2016-06.

Recent Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), that will supersede most existing revenue recognition guidance under US GAAP. The core principle of the guidance is that an entity should recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. Entities can choose to apply the standard using either the full retrospective approach or a modified retrospective approach. Entities electing the full retrospective adoption will apply the standard to each period presented in the financial statements. This means that entities will have to apply the new guidance as if it had been in effect since the inception of all its contracts with customers presented in the financial statements. Entities that elect the modified retrospective approach will apply the guidance retrospectively only to the most current period presented in the financial statements. This means that entities will have to recognize the cumulative effect of initially applying the new standard as an adjustment to the opening balance of retained earnings at the date of initial application. The new revenue standard will be applied to contracts that are in progress at the date of initial application. According to Accounting Standards Update No. 2015-14, Revenue from Contracts with Customers (“ASU 2015-14”), issued by the FASB in August 2015, the standard will be effective for annual and interim periods beginning after December 15, 2017. Company has yet to evaluate which adoption method it plans to use or the potential effect of the new standard on its consolidated financial statements.

In August 2014, the FASB issued Accounting Standards Update No. 2014-15, Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern (“ASU 2014-15”), which will require a reporting entity to evaluate, at each annual and interim reporting period, whether there are conditions or events that raise substantial doubt about the reporting entity's ability to continue as a going concern within one year after the date the financial statements are issued and provide related disclosures. The standard will be effective for annual periods ending after December 15, 2016, with early adoption permitted. The Company is in the process of evaluating the potential effect of the new standard on its consolidated financial statements. .

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In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities. ASU 2016-01 made modifications to how certain financial instruments should be measured and disclosed, including using the exit price notion when measuring the fair value, separating the presentation of financial assets and financial liabilities by measurement category on the balance sheet and eliminating the requirement to disclose the method and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost on the balance sheet. This guidance is effective for fiscal years beginning after December 15, 2017, including interim periods. The Company will evaluate the guidance and present the required disclosures in its consolidated financial statements at the time of adoption.

In February 2016, the FASB issued ASU No. 2016-02, Leases. ASU 2016-02 is aimed at making leasing activities more transparent and comparable, and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. ASU 2016-2 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2019, and all annual and interim reporting periods thereafter. Early adoption is permitted. The Company is currently evaluating the impact that the adoption of ASU 2016-2 will have on our consolidated financial statements and related disclosures.

In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based payment Accounting. ASU 2016-09 principally affects the recognition of excess tax benefits and deficiencies and the cash flow classification of share-based compensation related transactions. This guidance is effective for annual reporting periods beginning after December 15, 2016 and interim periods within those fiscal years with early adoption permitted. The Company will evaluate the guidance and present the required disclosures in its consolidated financial statements at the time of adoption.

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Sunesis Europe Limited, a United Kingdom corporation, and Sunesis Pharmaceuticals (Bermuda) Ltd., a Bermuda corporation, as well as a Bermuda limited partnership, Sunesis Pharmaceuticals International LP. All intercompany balances and transactions have been eliminated in consolidation.

Segment Reporting

Management has determined that the Company operates as a single reportable segment.

Significant Estimates and Judgments

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the Company’s consolidated financial statements and accompanying notes thereto. Actual results could differ materially from these estimates. Estimates, assumptions and judgments made by management include those related to the valuation of equity and related instruments, debt instruments, revenue recognition, stock-based compensation and clinical trial accounting.

Cash Equivalents and Marketable Securities

Invoices for certain services provided to the Company are denominated in foreign currencies. To manage the risk of future movements in foreign exchange rates that would affect such amounts, the Company may purchase certain European currencies or highly-rated investments denominated in those currencies, subject to similar criteria as for other investments defined in the Company’s investment policy. There is no guarantee that the related gains and losses will substantially offset each other, and the Company may be subject to exchange gains or losses as currencies fluctuate from quarter to quarter. To date, the Company has purchased Euros and Euro-denominated obligations of foreign governments and corporate debt. As of March 31, 2016 and December 31, 2015, the Company held cash and investments denominated in Euros with an aggregate fair value of $0.8 million and $0.7 million, respectively. Any cash, cash equivalent and marketable securities balances denominated in foreign currencies are recorded at their fair value based on the current exchange rate as of each balance sheet date. The resulting exchange gains or losses and those from amounts payable for services originally denominated in foreign currencies are recorded in other income (expense), net in the statements of operations and comprehensive loss.

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Fair Value Measurements

The Company measures cash equivalents, marketable securities and warrant liabilities at fair value on a recurring basis and warrants issued in connection with debt on a non-recurring basis using the following hierarchy to prioritize valuation inputs, in accordance with applicable GAAP:

Level 1 - quoted prices (unadjusted) in active markets for identical assets and liabilities that can be accessed at the measurement date.

Level 2 - inputs other than quoted prices included within Level 1 that are observable, either directly or indirectly.

Level 3 - unobservable inputs.

The Company’s Level 2 valuations of marketable securities are generally derived from independent pricing services based upon quoted prices in active markets for similar securities, with prices adjusted for yield and number of days to maturity, or based on industry models using data inputs, such as interest rates and prices that can be directly observed or corroborated in active markets.

The fair value of the warrants issued in connection with a loan security agreement (see Note 7) is determined using the Black-Scholes model, which requires inputs such as the expected term of the warrants, share price volatility and risk-free interest rate. As some of these inputs are unobservable, and require significant analysis and judgment to measure, these variables are classified as Level 3.

The Company does not measure cash, prepayments, accounts payable, accrued liabilities, deferred revenue and notes payable at fair value, as their carrying amounts approximated their fair value as of March 31, 2016 and December 31, 2015.

3. Loss per Common Share

Basic loss per common share is calculated by dividing net loss by the weighted-average number of common shares outstanding for the period. Diluted loss per common share is computed by dividing (a) net loss, less any anti-dilutive amounts recorded during the period for the change in the fair value of warrant liabilities, by (b) the weighted-average number of common shares outstanding for the period plus dilutive potential common shares as determined using the treasury stock method for options and warrants to purchase common stock.

The following table represents the potential common shares issuable pursuant to outstanding securities as of the related period end dates that were excluded from the computation of diluted loss per common share because their inclusion would have had an anti-dilutive effect (in thousands):

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4. Financial Instruments

Financial Assets

The following tables summarize the estimated fair value of the Company’s financial assets measured on a recurring basis as of the dates indicated, which were comprised solely of available-for-sale marketable securities with remaining contractual maturities of one year or less (in thousands):

There were no available-for-sale securities that were in an unrealized loss position, having been in such a position for less than 12 months, and deemed to be other-than-temporarily impaired as of March 31, 2016. As of March 31, 2016 the Company had U.S. corporate debt obligation with an estimated fair value of $9.8 million and does not intend to sell these securities before maturity.. 

There were no sales of available-for-sale securities during either the three months ended March 31, 2016 or 2015.

5. Royalty Agreement

In March 2012, the Company entered into a Revenue Participation Agreement (the “Royalty Agreement”), with RPI Finance Trust (“RPI”), an entity related to Royalty Pharma. In September 2012, pursuant to the provisions of the Royalty Agreement, RPI made a $25.0 million cash payment to the Company. The payment, less $3.1 million representing the fair value of the warrants granted under the arrangement, was initially classified as deferred revenue and is being amortized to revenue over the related performance period.

Revenue participation right payments will be made to RPI when and if vosaroxin is commercialized, at a rate of 6.75% of net sales of vosaroxin, on a product-by-product and country-by-country basis world-wide through the later of: (a) the expiration of the last to expire of certain specifically identified patents; (b) 10 years from the date of first commercial sale of such product in such country; or (c) the expiration of all applicable periods of data, market or other regulatory exclusivity in such country with respect to such product.

6. License Agreements

Biogen

In December 2013, the Company entered into a second amended and restated collaboration agreement with Biogen Idec MA, Inc. (the “Biogen 2nd ARCA”), to provide the Company with an exclusive worldwide license to develop, manufacture and

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commercialize SNS-062, a BTK inhibitor synthesized under the first amended and restated collaboration agreement with Biogen (the “Biogen 1st ARCA”), solely for oncology indications. The Company may be required to make a $2.5 million milestone payment depending on its development of SNS-062 and royalty payments depending on related product sales of SNS-062. All other of Sunesis’ rights and obligations contained in the Biogen 1st ARCA remain unchanged, except that potential future royalty payments to Sunesis were reduced to equal those amounts due to Biogen for potential future sales of SNS-062.

Takeda

In March 2011, Takeda Pharmaceuticals, Inc., a wholly-owned subsidiary of Takeda Pharmaceutical Company Limited (“Takeda”) purchased and exclusively licensed Biogen ’s rights to a PDK1 inhibitor program and a pan-Raf inhibitor program which were both originally developed through a collaboration agreement between Sunesis and Biogen. In January 2014, the Company entered into an amended and restated license agreement with Takeda (the “Amended Takeda Agreement”), to provide the Company with an exclusive worldwide license to develop and commercialize preclinical inhibitors of PDK1. In connection with the execution of the Amended Takeda Agreement, the Company paid an upfront fee and may be required to make up to $9.2 million in pre-commercialization milestone payments depending on its development of PDK1 inhibitors and royalty payments depending on related product sales, if any.

With respect to the pan-Raf inhibitor program, the Company may in the future receive up to $57.5 million in pre-commercialization event-based payments related to the development by Takeda of the first two indications for each of the licensed products directed against the Raf target and royalty payments depending on related product sales. Under this program, Takeda is currently conducting Phase 1 clinical studies of an oral investigative drug, TAK-580 (formerly MLN2480).

7. Notes Payable

On March 31, 2016, the Company entered into a loan and security agreement (the “Loan Agreement”) with Western Alliance Bank (“Western Bank”) and Solar Capital Ltd. (“Solar Capital,” and collectively with Western Bank, the “Lenders”) and Western Alliance, as Collateral Agent (the “Collateral Agent”). Pursuant to the terms of the Loan Agreement, the Lenders provided the Company with a loan in the principal amount of $15,000,000 of which $12,500,000 was funded on March 31, 2016 and $2,500,000 was funded on April 1, 2016, for working capital, to fund its general business requirements and to repay indebtedness of the Company to Oxford Finance LLC, Silicon Valley Bank and Horizon Technology Finance Corporation (collectively, the “Existing Lenders”) pursuant to the Loan and Security Agreement, dated as of October 18, 2011, entered into by and among the Existing Lenders and the Company (the “Oxford Loan Agreement”). On March 31, 2016, the Company used $7.2 million of the loan proceeds to repay the outstanding principal of $6.0 million, a final payment fee of $1.2 million and accrued interest of $45,000 under the Oxford Loan Agreement. The Company paid the Lenders a $0.1 million facility fee and $0.1 million in legal fees, and incurred legal fees of $49,000 in connection with closing the loan.

The Company will be required to pay interest on the borrowings under the Loan Agreement at a per annum rate equal to 8.54% plus the then effective one-month U.S. LIBOR rate. Payments under the Loan Agreement are monthly in arrears and interest-only for the first 12-months. Thereafter and until the scheduled maturity date of April 1, 2020, in addition to interest accrued during such period, the monthly payments will include an amount equal to the outstanding principal divided by 36 months, unless the interest only period is extended by a further six months, in which case the amortization period will be 30 months. A final payment equal to 3.75% of the original principal amount borrowed will be due upon maturity or such earlier date specified in the Loan Agreement. If the Company repays all amounts owed under the Loan Agreement prior to the maturity date, the Company will pay a prepayment fee equal to 2.0% of the amount prepaid if the prepayment occurs on or prior to March 31, 2017, 1.0% of the amount prepaid if the prepayment occurs after March 31, 2017 but on or prior to March 31, 2018 and 0.5% of the amount prepaid if the prepayment occurs thereafter.       

The facility fee and legal fees related to the debt are being accounted for as a debt discount and classified within notes payable on the Company’s balance sheet and amortized as interest expense over the term of the loan using the effective interest method.  The final payment is being accreted as interest expense over the term of the loan using the effective interest method

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In conjunction with the Loan Agreement, the Lenders were issued five-year warrants to purchase an aggregate of up to 1,248,012 shares of the Company’s common stock at a per share exercise price of $0.5409. The fair value of the warrants issued was estimated to be $0.5 million using a Black-Scholes valuation model with the following assumptions: common stock price at issuance of $0.54; exercise price of $0.5409; risk-free interest rate of 1.21% based upon observed risk-free interest rates; expected volatility of 111.96% based on the Company’s average historical volatility; expected term of five years, which is the contractual life of the warrants; and a dividend yield of 0%. The fair value was recorded as a debt discount within notes payable and an increase to additional paid-in capital on the Company’s balance sheet. The debt discount is being amortized as interest expense over the term of the Loan Agreement, using the effective interest method.

Pursuant to the Loan Agreement, the Company is bound by a variety of affirmative covenants during the term of the Loan Agreement, including, without limitation, certain information delivery requirements, notice requirements and obligations to maintain certain insurance. Additionally, the Company is bound by certain negative covenants setting forth actions that are not permitted to be taken during the term of the Loan Agreement without the Lenders’ consent, including, without limitation, incurring certain additional indebtedness, making certain asset dispositions, entering into certain mergers, acquisitions or other business combination transactions or incurring any non-permitted lien or other encumbrance on the Company’s assets. Upon the occurrence of an event of default under the Loan Agreement (subject to cure periods for certain events of default), all amounts owed by the Company thereunder would begin to bear interest at a rate that is 5.0% higher than the rate that would otherwise be applicable and may be declared immediately due and payable by the Collateral Agent. Events of default under the Loan Agreement include, among other things, the following: the occurrence of certain bankruptcy events; the failure to make payments under the Loan Agreement when due; the occurrence of a material impairment on the Collateral Agent’s security interest over the collateral, a material adverse change in the business, operations or condition (financial or otherwise) of the Company or material impairment of the prospect of repayment of the obligations under the Loan Agreement; the occurrence of a default under certain other agreements entered into by the Company; the rendering of certain types of judgments against the Company; the revocation of certain government approvals of the Company; any breach by the Company of any covenant (subject to cure periods for certain covenants) made in the Loan Agreement; and the failure of any representation or warranty made by the Company in connection with the Loan Agreement to be correct in all material respects when made.

The Collateral Agent, for the benefit of the Lenders, has a perfected security interest in substantially all of the Company’s property, rights and assets, except for intellectual property, to secure the payment of all amounts owed to the Lenders under the Loan Agreement. Upon marketing approval of vosaroxin, the Collateral Agent, for the benefit of the Lenders, will also have a perfected security interest in the Company’s intellectual property rights relating to vosaroxin.

Aggregate future minimum payments due under the Loan Agreement as of March 31, 2016 were as follows (in thousands):

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8. Stockholders’ Equity

Controlled Equity Offerings

In August 2011, the Company entered into a Controlled Equity Offering^SM sales agreement (the “Sales Agreement”), with Cantor Fitzgerald & Co. (“Cantor”), as agent and/or principal, pursuant to which the Company could issue and sell shares of its common stock having an aggregate gross sales price of up to $20.0 million. In April 2013, the Sales Agreement was amended to provide for an increase of $30.0 million in the aggregate gross sales price under the Sales Agreement. In March 2015, the Sales Agreement was further amended to provide for an additional increase of $30.0 million in the aggregate gross sales price under the Sales Agreement. The Company will pay Cantor a commission of up to 3.0% of the gross proceeds from any common stock sold through the Sales Agreement, as amended.

During the three months ended March 31, 2016, no shares of common stock were sold under the Sales Agreement. As of March 31, 2016, $18.2 million of common stock remained available to be sold under this facility, subject to certain conditions as specified in the Sales Agreement, as amended.

9. Stock-Based Compensation

Employee stock-based compensation expense is calculated based on the grant-date fair value of awards ultimately expected to vest, and is recorded on a straight-line basis over the vesting period of the awards. Forfeitures are estimated at the time of grant, based on historical option cancellation information, and revised in subsequent periods if actual forfeitures differ from those estimates.

The following table summarizes stock-based compensation expense related to the Company’s stock-based awards for the periods indicated (in thousands):

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The following discussion and analysis of our financial condition as of March 31, 2016 and results of operations for the three months ended March 31, 2016 should be read together with our condensed consolidated financial statements and related notes included elsewhere in this Quarterly Report on Form 10-Q and in our other Securities and Exchange Commission, or SEC, filings, including our Annual Report on Form 10-K for the year ended December 31, 2015, filed with the SEC on March 14, 2016.

This discussion and analysis contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and the Private Securities Litigation Reform Act of 1995, which involve risks, uncertainties and assumptions. All statements, other than statements of historical facts, are “forward-looking statements” for purposes of these provisions, including without limitation any statements relating to our strategy, including receiving approval of vosaroxin from the European Medicines Agency, our regulatory and clinical strategies for gaining marketing approval in the United States, our marketing plans and commercialization strategies for vosaroxin, if approved, and the commercial potential of vosaroxin, presenting clinical data and initiating clinical trials, our future research and development activities, including clinical testing and the costs and timing thereof, sufficiency of our cash resources, our ability to raise additional funding when needed, any statements concerning anticipated regulatory activities or licensing or collaborative arrangements, our research and development and other expenses, our operations and legal risks, and any statement of assumptions underlying any of the foregoing. In some cases, forward-looking statements can be identified by the use of terminology such as “anticipates,” “believe,” “continue,” “estimates,” “expects,” “intend,” “look forward,” “may,” “could,” “seeks,” “plans,” “potential,” or “will” or the negative thereof or other comparable terminology. Although we believe that the expectations reflected in the forward-looking statements contained herein are reasonable, there can be no assurance that such expectations or any of the forward-looking statements will prove to be correct, and actual results could differ materially from those projected or assumed in the forward-looking statements. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of many factors, including but not limited to those set forth under “Risk Factors,” and elsewhere in this report. We urge you not to place undue reliance on these forward-looking statements, which speak only as of the date of this report. All forward-looking statements included in this report are based on information available to us on the date of this report, and we assume no obligation to update any forward-looking statements contained in this report.

In this report, “Sunesis,” the “Company,” “we,” “us,” and “our” refer to Sunesis Pharmaceuticals, Inc. and its wholly-owned subsidiaries, except where it is made clear that the term means only the parent company.

Overview

We are a biopharmaceutical company focused on the development and commercialization of our pipeline of new oncology therapeutics for the potential treatment of solid and hematologic cancers. Our most advanced program is QINPREZO^TM (vosaroxin), our product candidate for the potential treatment of acute myeloid leukemia, or AML.

In October 2014, we announced the results of a Phase 3, multi-national, randomized, double-blind, placebo-controlled trial of vosaroxin in combination with cytarabine in patients with relapsed or refractory AML, or the VALOR trial. The VALOR trial, which enrolled 711 adult patients, was designed to evaluate the effect of vosaroxin in combination with cytarabine, a widely used chemotherapy in AML, on overall survival as compared to placebo in combination with cytarabine, and was conducted at 124 study sites in 15 countries. Patients treated with vosaroxin achieved increased overall survival compared to those treated with placebo (7.5 months vs 6.1 months, HR=0.87), the primary endpoint, but this difference did not achieve statistical significance (p=0.06). The complete remission (CR) rate, the sole secondary efficacy endpoint in the trial, did demonstrate a significant difference for the vosaroxin combination arm (30.1% vs 16.3%, p < 0.0001). Detailed results of the VALOR trial were presented in the "Late Breaking Abstracts" session of the American Society of Hematology (ASH) Annual Meeting in December 2014 and additionally published in the September 2015 issue of The Lancet Oncology.

The VALOR trial did not meet its primary endpoint of demonstrating a statistically significant improvement in overall survival, but based upon the favorable results of other predefined analyses of the data, in November 2014, we submitted a letter of intent to the European Medicines Agency, or EMA, describing our intention to file a marketing authorization application, or MAA, for marketing authorization of vosaroxin plus cytarabine for the treatment of relapsed or refractory AML. In June 2015, we met separately with our Rapporteur and Co-Rapporteur, who are two appointed members of the EMA’s Committee of Human Medicinal Products. Based upon feedback from these meetings, we filed an MAA with the EMA at the end of 2015. In July 2015, we met with the U.S. Food and Drug Administration, or FDA, to discuss a potential regulatory filing in the U.S. Based upon the meeting, the FDA recommended that we provide additional clinical evidence prior to any regulatory filing in the U.S. As a result, we are evaluating regulatory and clinical strategies with the goal of gaining future marketing approval in the U.S.

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In the second half of 2013, we announced the initiation of three Phase 1/2 investigator-sponsored trials of vosaroxin, either as a standalone therapy or in combination with approved compounds, in various indications of AML and high-risk myelodysplastic syndrome, or MDS. The trials are being conducted at the University of Texas MD Anderson Cancer Center, or MDACC, Weill Cornell Medical College and New York-Presbyterian Hospital, and the Washington University School of Medicine, or Washington University.

In December 2015, preliminary results from the ongoing Phase 1b/2 MDACC-sponsored trial of vosaroxin in combination with decitabine in older patients with previously untreated AML and high-risk MDS and the ongoing Phase 1b/2 Washington University-sponsored trial of vosaroxin in combination with azacitidine in patients with intermediate- or high-risk MDS, were presented at the ASH Annual Meeting.

In March 2016, we announced that the first patients have been treated in the investigator-sponsored VITAL (Vosaroxin and Infusional Cytarabine for Frontline Treatment of Acute Myeloid Leukemia) Phase 2 study of vosaroxin in combination with cytarabine in patients with previously untreated acute myeloid leukemia (AML). The trial is being conducted at the Vanderbilt-Ingram Cancer Center at Vanderbilt University.

In January 2014, we announced the expansion of our oncology franchise through separate global licensing agreements for two preclinical kinase inhibitor programs. The first agreement, with Biogen, is for global commercial rights to SNS-062, a selective non-covalently binding oral inhibitor of BTK. In March 2016, the first subjects were dosed in a Phase 1A, randomized, double-blind, placebo-controlled dose-ranging study to investigate the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of our oral, next-generation, non-covalently binding BTK-inhibitor, SNS-062, in healthy subjects.  The Phase 1A study is being conducted in Belgium, pursuant to a Clinical Trial Application (CTA).   With a successful study outcome, SNS-062 is expected to proceed to a Phase 1B/2 study in patients with B-cell malignancies later this year.

The second agreement, with Takeda, is for global commercial rights to several potential first-in class, pre-clinical inhibitors of the novel target PDK1. In 2014, we selected two PDK1 inhibitors, SNS-229 and SNS-510, of which we have taken one, SNS-229 into IND-enabling absorption, distribution, metabolism and excretion, or ADME, and safety studies.

Both BTK and PDK1 programs were originally developed under a research collaboration agreement between Biogen and Sunesis. In 2011, Biogen exclusively licensed the PDK1 program to Takeda along with the more advanced program, TAK-580, a pan-RAF inhibitor currently in the maximum tolerated dose cohort expansion stage of a Takeda Phase 1, multicenter dose escalation study. We currently expect that SNS-062 and SNS-229 will be developed exclusively by Sunesis for the foreseeable future.

Recent Financial History

Equity Financing Agreements

In December 2015, we completed underwritten offerings of (i) 10,996,191 shares of our common stock, that included the exercise of the underwriter's over-allotment option of 1,434,286 shares, at a price of $0.84 per share, and (ii) 20,200 shares of our non-voting Series B Convertible Preferred Stock (“Series B Stock”) at a price of $840.00 per share. Gross proceeds from the sale were $26.2 million and net proceeds were $25.2 million. Each share of non-voting Series B Stock is convertible into 1,000 shares of our common stock, provided that conversion will be prohibited if, as a result, the holder and its affiliates would own more than 9.98% of the total number of shares of our common stock then outstanding.

Controlled Equity Offerings

In August 2011, we entered into a Controlled Equity Offering^SM sales agreement, or the Sales Agreement, with Cantor Fitzgerald & Co., or Cantor, as agent and/or principal, pursuant to which we could issue and sell shares of our common stock having an aggregate gross sales price of up to $20.0 million. In April 2013, the Sales Agreement was amended to provide for an increase of $30.0 million in the aggregate gross sales price under the Sales Agreement. In March 2015, the Sales Agreement was further amended to provide for an additional increase of $30.0 million in the aggregate gross sales price under the Sales Agreement. We will pay Cantor a commission of up to 3.0% of the gross proceeds from any common stock sold through the Sales Agreement, as amended.

During the first quarter of 2016, no shares of common stock were sold under the Sales Agreement. As of March 31, 2016, $18.2 million of common stock remains available to be sold under the Sales Agreement, as amended, subject to certain conditions as specified in the agreement.

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Loan Agreement

On March 31, 2016, the Company entered into a loan and security agreement (the “Loan Agreement”) with Western Alliance Bank (“Western Bank”) and Solar Capital Ltd. (“Solar Capital,” and collectively with Western Bank, the “Lenders”) and Western Alliance, as Collateral Agent (the “Collateral Agent”). Pursuant to the terms of the Loan Agreement, the Lenders provided the Company with a loan in the principal amount of $15,000,000 of which $12,500,000 was funded on March 31, 2016 and $2,500,000 was funded on April 1, 2016, for working capital, to fund its general business requirements and to repay indebtedness of the Company to Oxford Finance LLC, Silicon Valley Bank and Horizon Technology Finance Corporation (collectively, the “Existing Lenders”) pursuant to the Loan and Security Agreement, dated as of October 18, 2011, entered into by and among the Existing Lenders and the Company (the “Oxford Loan Agreement”). On March 31, 2016, the Company used $7.2 million of the loan proceeds to repay the outstanding principal of $6.0 million, a final payment fee of $1.2 million and accrued interest of $45,000 under the Oxford Loan Agreement. The Company paid the Lenders a $0.1 million facility fee and $0.1 million in legal fees, and incurred legal fees of $49,000 in connection with closing the loan.      

Capital Requirements

We have incurred significant losses in each year since our inception. As of March 31, 2016, we had cash, cash equivalents and marketable securities of $40.0 million and an accumulated deficit of $569.5 million. We expect to continue to incur significant losses for the foreseeable future as we continue the development process and seek regulatory approvals for vosaroxin.

We will need to raise substantial additional capital to complete the development and potential commercialization of vosaroxin, and expect to finance our future cash needs primarily through equity issuances, debt arrangements, one or more possible licenses, collaborations or other similar arrangements with respect to development and/or commercialization rights to vosaroxin, or a combination of the above. However, we do not know whether additional funding will be available on acceptable terms, or at all. If we are unable to raise required funding on acceptable terms or at all, we will need to reduce operating expenses, enter into a collaboration or other similar arrangement with respect to development and/or commercialization rights to vosaroxin, outlicense intellectual property rights to vosaroxin or our other development programs, sell unsecured assets, or a combination of the above, or be forced to delay or reduce the scope of our vosaroxin development program, potentially including any regulatory filings related to the VALOR trial, and/or limit or cease our operations.

Critical Accounting Policies and Significant Judgments and Estimates

There have been no significant changes during the three months ended March 31, 2016 to our critical accounting policies and significant judgments and estimates as disclosed in our management’s discussion and analysis of financial condition and results of operations included in our Annual Report on Form 10-K for the year ended December 31, 2015.

Overview of Revenues

We have not generated any revenue from the sale of commercial products, and do not anticipate product sales until at least 2017, if at all. Over the past four years, we have generated revenue primarily through a Revenue Participation Agreement, or the Royalty Agreement, which was entered into in March 2012 with RPI Finance Trust, or RPI, an entity related to Royalty Pharma. In September 2012, we received a $25.0 million cash payment from RPI pursuant to the provisions of the Royalty Agreement. The payment, less $3.1 million representing the fair value of the warrants granted under the arrangement, was initially classified as deferred revenue and is being amortized to revenue over the related performance period.

Overview of Operating Expenses

Research and Development expense. Research and development expense consists primarily of clinical trial costs, which include: payments for work performed by our contract research organizations, clinical trial sites, labs and other clinical service providers and for drug packaging, storage and distribution; drug manufacturing costs, which include costs for producing drug substance and drug product, and for stability and other testing; personnel costs, including non-cash stock-based compensation; other outside services and consulting costs; and payments under license agreements. We expense all research and development costs as they are incurred.

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We are currently focused on the development of vosaroxin for the treatment of AML, as well as our portfolio of kinase inhibitors. For vosaroxin, based on results of translational research, our own and investigator-sponsored trials, regulatory and competitive concerns and our overall financial resources, we anticipate that we will make determinations as to which indications to pursue and patient populations to treat in the future, and how much funding to direct to each indication, which will affect our research and development expense. If we proceed to commercialization following the approval of either an MAA filing with the EMA or a New Drug Application, or NDA, filing with the FDA, research and development costs may increase in the future. Due to the above uncertainties and other risks inherent in the development process, we are unable to estimate the costs we will incur in the vosaroxin development program in the future.

If we engage a development or commercialization partner for our vosaroxin program, or if, in the future, we acquire additional product candidates, our research and development expenses could be significantly affected. We cannot predict whether future licensing or collaborative arrangements will be secured, if at all, and to what degree such arrangements would affect our development plans and capital requirements.

We anticipate continuing expenditures associated with advancing the SNS-062 and SNS-229 programs in 2016 and beyond. Additionally, under the Takeda Agreement, we have the right to participate in co-development and co-promotion activities for the related product candidates, including TAK-580 (formerly MLN2480), an oral pan-RAF inhibitor currently in Phase 1 clinical studies being conducted by Takeda. If we were to exercise our option on this or other product candidates, our research and development expense would increase significantly.

General and Administrative expense. General and administrative expense consists primarily of personnel costs for the related employees, including non-cash stock-based compensation; outside service costs, including fees paid to external legal advisors, marketing consultants and our independent registered public accounting firm; facilities expenses; and other administrative costs. If we proceed to commercialization in either Europe or the United States, we anticipate general and administrative expenses to increase in the future, including additional costs related to selling and marketing.

Results of Operations

Revenue

Total revenue was $0.6 million for the three months ended March 31, 2016 as compared to $0.9 million for the same period in 2015. The decrease of $0.3 million was primarily due to the increase in the estimated performance period through which the remaining balance of deferred revenue will be amortized.  

Research and Development Expense

Research and development expense was $6.2 million for the three months ended March 31, 2016 as compared to $4.5 million for the same periods in 2015. The increase of $1.7 million between the comparable three month periods was primarily due to increase of $1.3 million in consulting and other outside services costs and $0.4 million in clinical trials and medical affairs expenses.

General and Administrative Expense

General and administrative expense was $4.3 million for the three months ended March 31, 2016 as compared to $5.1 million for the same periods in 2015. The decrease of $0.8 million between the comparable three month periods was primarily due to a $0.8 million decrease in personnel costs and professional services and commercial costs.

Interest Expense

Interest expense was $0.3 million for the three months ended March 31, 2016 as compared to $0.2 million for the same period in 2015. The increase of $0.1 million between the comparable three month periods was primarily due to the repayment of the loan interest.

Liquidity and Capital Resources

Sources of Liquidity

Since our inception, we have funded our operations primarily through the issuance of common and preferred stock and other equity instruments, debt financings, receipts from our collaboration partners, the sale of revenue participation rights, and research grants.

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Our cash, cash equivalents and marketable securities totaled $40.0 million as of March 31, 2016, as compared to $46.4 million as of December 31, 2015. The decrease of $6.4 million was primarily due to $10.7 million of net cash used in operating activities, $7.2 million of final payments against notes payable, $0.8 million of principal payments against notes payable, partially offset by $12.3 million net loan proceeds.

On March 31, 2016, the Company entered into a loan and security agreement (the “Loan Agreement”) with Western Alliance Bank (“Western Bank”) and Solar Capital Ltd. (“Solar Capital,” and collectively with Western Bank, the “Lenders”) and Western Alliance, as Collateral Agent (the “Collateral Agent”). Pursuant to the terms of the Loan Agreement, the Lenders provided the Company with a loan in the principal amount of $15,000,000 of which $12,500,000 was funded on March 31, 2016 and $2,500,000 was funded on April 1, 2016. For working capital, to fund its general business requirements and to repay indebtedness of the Company to Oxford Finance LLC, Silicon Valley Bank and Horizon Technology Finance Corporation (collectively, the “Existing Lenders”) pursuant to the Loan and Security Agreement, dated as of October 18, 2011, entered into by and among the Existing Lenders and the Company (the “Oxford Loan Agreement”). On March 31, 2016, the Company used $7.2 million of the loan proceeds to repay the outstanding principal of $6.0 million, a final payment fee of $1.2 million and accrued interest of $45,000 under the Oxford Loan Agreement. The Company paid the Lenders a $0.1 million facility fee and $0.1 million in legal fees, and incurred legal fees of $49,000 in connection with closing the loan.

In December 2015, we completed underwritten offerings of (i) 10,996,191 shares of our common stock, that included the exercise of the underwriter's over-allotment option of 1,434,286 shares, at a price of $0.84 per share, and (ii) 20,200 shares of our non-voting Series B Convertible Preferred Stock (“Series B Stock”) at a price of $840.00 per share. Gross proceeds from the sale were $26.2 million and net proceeds were $25.2 million. Each share of non-voting Series B Stock is convertible into 1,000 shares of our common stock, provided that conversion will be prohibited if, as a result, the holder and its affiliates would own more than 9.98% of the total number of shares of our common stock then outstanding.

In August 2011, we entered into the Sales Agreement, with Cantor as agent and/or principal, pursuant to which we could issue and sell shares of our common stock having an aggregate gross sales price of up to $20.0 million. In April 2013, the Sales Agreement was amended to provide for an increase of $30.0 million in the aggregate gross sales price under the Sales Agreement. In March 2015, the Sales Agreement was further amended to provide for an additional increase of $30.0 million in the aggregate gross sales price under the Sales Agreement. We will pay Cantor a commission of up to 3.0% of the gross proceeds from any common stock sold through the Sales Agreement, as amended.

During the three months ended March 31, 2016, no shares of common stock were sold under the Sales Agreement. As of March 31, 2016, $18.2 million of common stock remains available to be sold under this facility, subject to certain conditions as specified in the Sales Agreement.

Cash Flows

Net cash used in operating activities was $10.7 million for the three months ended March 31, 2016, as compared to $11.6 million for the same period in 2015. Net cash used in the 2016 period resulted primarily from the net loss of $10.1 million and changes in operating assets and liabilities of $2.2 million, including the payment of a final fee of $1.2 million under the Oxford Loan Agreement, partially offset by net adjustments for non-cash items of $1.6 million. Net cash used for the same period in 2015 resulted primarily from the net loss of $9.1 million and changes in operating assets and liabilities of $4.6 million, partially offset by net adjustments for non-cash items of $2.1 million.

Net cash provided by investing activities was $3.4 million for the three months ended March 31, 2016, as compared to net cash used in investing activities of $0.2 million for the same period in 2015. Net cash provided during the three months ended March 31, 2016 consisted primarily of proceeds from maturities of marketable securities, partially offset by purchases of marketable securities. Net cashed used during the three months ended March 31, 2015 consisted primarily of purchases of marketable securities, partially offset by proceeds from maturities of marketable securities.

Net cash provided by financing activities was $4.3 million for the three months ended March 31, 2016, as compared to $8.4 million for the same period in 2015. Net cash provided in the 2016 period resulted primarily from net proceeds of $12.3 million from debt financing, offset by $8.0 million of principal and final payments against notes payable. Net cash provided for the same period in 2015 resulted primarily from net cash proceed of $10.0 million from sales of our common stock through the Sales Agreement with Cantor, partially offset by $1.6 million of principal payment against notes payable.

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Operating Capital Requirements

We expect to continue to incur substantial operating losses in the future. We will not receive any product revenue until a product candidate has been approved by the EMA, FDA, or similar regulatory agencies in other countries, and has been successfully commercialized, if at all. We will need to raise substantial additional funding to complete the development and potential commercialization of vosaroxin. Additionally, we may evaluate in-licensing and acquisition opportunities to gain access to new drugs or drug targets that would fit with our strategy. Any such transaction would likely increase our funding needs in the future.

Our future funding requirements will depend on many factors, including but not limited to:

We believe that we currently have the resources to fund our operations to the middle of 2017. We will need to raise substantial additional capital to complete the development and potential commercialization of vosaroxin. Until we can generate a sufficient amount of licensing or collaboration or product revenue to finance our cash requirements, which we may never do, we expect to finance our future cash needs primarily through equity issuances, debt arrangements, one or more possible licenses, collaborations or other similar arrangements with respect to development and/or commercialization rights to vosaroxin, or a combination of the above.

Our failure to raise significant additional capital in the future would force us to delay or reduce the scope of our vosaroxin and other development programs, potentially including any additional clinical trials or subsequent regulatory filings in Europe or the United States, and/or limit or cease our operations. Any one of the foregoing would have a material adverse effect on our business, financial condition and results of operations.

Contractual Obligations

The following table summarizes our long-term contractual obligations as of March 31, 2016 (in thousands):

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The above amounts exclude potential payments under:

We also have agreements with contract research organizations clinical sites and other third party contractors for the conduct of our clinical trials. We generally make payments to these entities based upon the activities they perform related to the particular clinical trial. There are generally no penalty clauses for cancellation of these agreements if notice is duly given and payment is made for work performed by the third party under the related agreement.

Off-Balance Sheet Arrangements

Since our inception, we have not had any off-balance sheet arrangements or relationships with unconsolidated entities or financial partnerships, such as entities often referred to as structured finance or variable interest entities, which are typically established for the purpose of facilitating off-balance sheet arrangements or other contractually narrow or limited purposes.

Interest Rate and Market Risk

As of March 31, 2016 and December 31, 2015, we had $40.0 million and $46.4 million, respectively, in cash, cash equivalents and marketable securities. The securities in our investment portfolio are not leveraged and are classified as available-for-sale, which, due to their short-term nature, are subject to minimal interest rate risk. We currently do not hedge our interest rate risk exposure. Because of the short-term maturities of our investments, we do not believe that a change in market rates would have a significant impact on the value of our investment portfolio.

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We are subject to interest rate fluctuation exposure through the outstanding principal on our notes payable.  Borrowings under the notes payable bear interest at a rate equal to the one-month LIBOR plus 8.54% per annum.  As of March 31, 2016, the interest rate on our borrowings under the notes payable was 8.98% per annum.  An increase in the one-month LIBOR of 100 basis points above the current one-month LIBOR rates would increase our interest expense by $0.4 million through the maturity of the loan.

The primary objective of our investment activities is to preserve capital while at the same time maximizing the income we receive from our investments without significantly increasing risk. To achieve this objective, we maintain our portfolio of cash equivalents and short-term investments in a variety of highly rated securities, which may include money market funds and U.S. and European government obligations and corporate debt obligations (including certificates of deposit, corporate notes and commercial paper). These securities are classified as available for sale and consequently are recorded on the balance sheet at fair value with unrealized gains or losses reported as a separate component of accumulated other comprehensive income (loss). In the past, we have generally purchased investments with an original maturity of less than one year, although our policy allows for the purchase of securities with a maturity of up to two years. Our holdings of the securities of any one corporate issuer do not exceed 10% of the portfolio at the time of purchase. If interest rates rise, the market value of our investments may decline, which could result in a realized loss if we are forced to sell an investment before its scheduled maturity. We do not utilize derivative financial instruments to manage our interest rate risks.

The tables below present the original principal amounts and weighted-average interest rates by maturity period for our investment portfolio as of the dates indicated (in thousands, except percentages):

Foreign Currency Exchange Rate Risk

We consider our direct exposure to foreign exchange rate fluctuations to be minimal. Invoices for certain services provided to us are denominated in foreign currencies, including the Euro and British pound, among others. Therefore, we are exposed to adverse movements in the related foreign currency exchange rates. To manage this risk, we may purchase certain European currencies or highly-rated investments denominated in those currencies, subject to similar criteria as for other investments allowed by our investment policy. We do not make these purchases for trading or speculative purposes, and there is no guarantee that the related gains and losses will substantially offset each other.

As of March 31, 2016 and December 31, 2015, we held cash and investments denominated in Euros with an aggregate fair value of $0.8 million and $0.7 million, respectively. The balances are recorded at their fair value based on the current exchange rate as of each balance sheet date. The resulting exchange gains or losses and those from amounts payable for services originally denominated in foreign currencies are recorded in other income (expense), net in the statements of operations and comprehensive loss.

Evaluation of Disclosure Controls and Procedures

We maintain disclosure controls and procedures, as such term is defined in SEC Exchange Act Rule 13a-15(e), that are designed to ensure that information required to be disclosed in our reports under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and that such information is accumulated and communicated to our management, including our Chief Executive Officer and Chief 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.

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As required by SEC Exchange Act Rule 13a-15(b), we carried out an evaluation, under the supervision and with the participation of our management, including our Chief Executive Officer and Chief 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 Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of the end of the period covered by this Quarterly Report on Form 10-Q.

Changes in Internal Control over Financial Reporting

There were no changes in our internal control over financial reporting , as defined in rules 13a-15(f) under the securities and exchange act of 1934, that occurred during the quarter ended March 31, 2016 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II. OTHER INFORMATION

From time to time, we may be involved in routine legal proceedings, as well as demands, claims and threatened litigation, which arise in the normal course of our business. The ultimate outcome of any litigation is uncertain and unfavorable outcomes could have a negative impact on our results of operations and financial condition. Regardless of outcome, litigation can have an adverse impact on us because of the defense costs, diversion of management resources and other factors.

We believe there is no litigation pending that could, individually or in the aggregate, have a material adverse effect on our results of operations or financial condition.

Investing in our common stock involves a high degree of risk. You should carefully consider the risks and uncertainties described below and all information contained in this Quarterly Report on Form 10-Q, as each of these risks could adversely affect our business, operating results and financial condition. If any of the possible adverse events described below actually occurs, we may be unable to conduct our business as currently planned and our financial condition and operating results could be harmed. In addition, the trading price of our common stock could decline due to the occurrence of any of these risks, and you may lose all or part of your investment.

Please see the language regarding forward-looking statements in “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

We have marked with an asterisk (*) those risk factors below that reflect substantive changes from the risk factors included in our Annual Report on Form 10-K for the year ended December 31, 2015 that was filed with the SEC on March 14, 2016.

Risks Related to Our Business

We need to raise substantial additional funding to pursue our regulatory strategy for the potential commercialization of QINPREZO^TM (vosaroxin), and to continue the development of vosaroxin and our other programs.

We believe that with $40.0 million in cash and investments held as of March 31, 2016, we currently have the resources to fund our operations to the middle of 2017.

However, we will need to raise substantial additional capital to:

Our future funding requirements and sources will depend on many factors, including but not limited to the:

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Until we can generate a sufficient amount of licensing, collaboration or product revenue to finance our cash requirements, which we may never do, we expect to finance future cash needs primarily through equity issuances, debt arrangements, one or more possible licenses, collaborations or other similar arrangements with respect to development and/or commercialization rights to vosaroxin or our other development programs, or a combination of the above. Any issuance of convertible debt securities, preferred stock or common stock may be at a discount from the then-current trading price of our common stock. If we issue additional common or preferred stock or securities convertible into common or preferred stock, our stockholders will experience additional dilution, which may be significant. Further, we do not know whether additional funding will be available on acceptable terms, or at all. If we are unable to raise substantial additional funding on acceptable terms, or at all, we will be forced to delay or reduce the scope of our vosaroxin or other development programs, potentially including any additional clinical trials or subsequent regulatory filings in Europe and the United States related to vosaroxin, and/or limit or cease our operations.

We have incurred losses since inception and anticipate that we will continue to incur losses for the foreseeable future. We may not ever achieve or sustain profitability.*

We are not profitable and have incurred losses in each year since our inception in 1998. Our net losses for the three months ended March 31, 2016 and the years ended December 31, 2015 and 2014 were $10.0 million, $36.7 million and $43.0 million, respectively. As of March 31, 2016, we had an accumulated deficit of $569.5 million. We do not currently have any products that have been approved for marketing, and we continue to incur substantial development and general and administrative expenses related to our operations. We expect to continue to incur losses for the foreseeable future, and we expect these losses to increase significantly as we seek regulatory approvals for vosaroxin, and as we prepare to commercialize vosaroxin, if approved. Our losses, among other things, have caused and will continue to cause our stockholders’ equity and working capital to decrease.

To date, we have derived substantially all of our revenue from license and collaboration agreements. We currently have two agreements, the Biogen 2nd ARCA and the Amended Takeda Agreement, which each include certain pre-commercialization event-based and royalty payments. We cannot predict whether we will receive any such payments under these agreements in the foreseeable future, or at all.

We also do not anticipate that we will generate revenue from the sale of products until at least 2017, if at all. In the absence of additional sources of capital, which may not be available to us on acceptable terms, or at all, the development of vosaroxin or future product candidates, if any, may be reduced in scope, delayed or terminated. If our product candidates or those of our collaborators fail in clinical trials or do not gain regulatory approval, or if our future products do not achieve market acceptance, we may never become profitable. Even if we achieve profitability in the future, we may not be able to sustain profitability in subsequent periods.

The development of vosaroxin could be halted or significantly delayed for various reasons; our clinical trials for vosaroxin may not lead to regulatory approval.

Vosaroxin is vulnerable to the risks of failure inherent in the drug development process. Our VALOR trial failed to meet its primary endpoint, and we may not be able to obtain regulatory approval for commercialization in any of the United States, Europe, or in other regions. Based upon a meeting with the FDA held in July 2015, the FDA recommended that we provide additional clinical evidence prior to any regulatory filing in the United States. We may also need to conduct significant additional preclinical studies and clinical trials before we can attempt to demonstrate that vosaroxin is safe and effective to the satisfaction of the EMA and other regulatory authorities. Failure can occur at any stage of the development process, and successful preclinical studies and early clinical trials do not ensure that later clinical trials will be successful. A number of companies in the pharmaceutical industry have suffered significant setbacks in advanced clinical trials, even after obtaining promising results in earlier trials.

For example, we terminated two Phase 2 clinical trials of vosaroxin in small cell and non-small cell lung cancer, and the LI-1 trial, conducted by a co-operative group in Europe, was halted at an interim data analysis. If our clinical trials result in unacceptable toxicity or lack of efficacy, we may have to terminate them. If clinical trials are halted, or if they do not show that vosaroxin is safe and effective in the indications for which we are seeking regulatory approval, our future growth will be limited and we may not have any other product candidates to develop.

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We do not know whether any future clinical trials with vosaroxin or any of our product candidates will be completed on schedule, or at all, or whether our ongoing or planned clinical trials will begin or progress on the time schedule we anticipate. The commencement of future clinical trials could be substantially delayed or prevented by several factors, including:

The completion of our clinical trials could be substantially delayed or prevented by several factors, including:

Additionally, our clinical trials may be suspended or terminated at any time by the FDA, other regulatory authorities, or ourselves. Any failure to complete or significant delay in completing clinical trials for our product candidates could harm our financial results and the commercial prospects for our product candidates.

We rely on a limited number of third-party manufacturers that are capable of manufacturing the vosaroxin active pharmaceutical ingredient, or API, and finished drug product, or FDP, to supply us with our vosaroxin API and FDP. If we fail to obtain sufficient quantities of these materials, the development and potential commercialization of vosaroxin could be halted or significantly delayed.

We do not currently own or operate manufacturing facilities and lack the capability to manufacture vosaroxin on a clinical or commercial scale. As a result, we rely on third parties to manufacture vosaroxin API and FDP. The vosaroxin API is classified as a cytotoxic substance, limiting the number of available manufacturers for both API and FDP.

We currently rely on a single contract manufacturer for the production of vosaroxin API and a single contract manufacturer to formulate the vosaroxin API and fill and finish vials of the vosaroxin FDP. If our third-party vosaroxin API or FDP manufacturers are unable or unwilling to produce the vosaroxin API or FDP we require, we would need to establish arrangements with one or more alternative suppliers. However, establishing a relationship with an alternative supplier would likely delay our ability to produce vosaroxin API or FDP. Our ability to replace an existing manufacturer would also be difficult and time consuming because the number of potential manufacturers is limited and the FDA, EMA or other corresponding state agencies must approve any replacement manufacturer before it can be an approved commercial supplier. Such approval would require new testing, stability programs and compliance inspections. It may be difficult or impossible for us to identify and engage a replacement manufacturer on acceptable terms in a timely manner, or at all. We expect to continue to depend on third-party contract manufacturers for all our vosaroxin API and FDP needs for the foreseeable future.

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Vosaroxin requires precise, high quality manufacturing. For example, in the past, we observed visible particles during stability studies of two vosaroxin FDP lots which resulted from process impurities in the vosaroxin API that, when formulated into the packaged vial of the vosaroxin FDP, resulted in the formation of these particles. We have since addressed this issue by the implementation of a revised manufacturing process to control the impurities and thereby minimize particle formation, however, there is no assurance that similar issues will not arise in the future as we prepare for regulatory approval and potential commercialization of vosaroxin.

In addition to process impurities, the failure of our contract manufacturers to achieve and maintain high manufacturing standards in compliance with cGMP regulations could result in other manufacturing errors leading to patient injury or death, product recalls or withdrawals, delays or interruptions of production or failures in product testing or delivery. Although contract manufacturers are subject to ongoing periodic unannounced inspection by the FDA, EMA or other corresponding state agencies to ensure strict compliance with cGMP and other applicable government regulations and corresponding foreign standards, any such performance failures on the part of a contract manufacturer could result in the delay or prevention of filing or approval of marketing applications for vosaroxin, cost overruns or other problems that could seriously harm our business. This would deprive us of potential product revenue and result in additional losses.

The failure to enroll patients for clinical trials may cause delays in developing vosaroxin.

We may encounter delays if we are unable to enroll enough patients to complete clinical trials of vosaroxin. Based upon a meeting with the FDA held in July 2015, the FDA recommended that we provide additional clinical evidence prior to any regulatory filing in the United States, therefore we will need to enroll patients in the related clinical trial or trials and may also be required to enroll patients for additional clinical trials required by the EMA or other regulatory authorities. Patient enrollment depends on many factors, including the size of the patient population, the nature of the protocol, the proximity of patients to clinical sites, the number and nature of competing treatments and ongoing clinical trials of competing drugs for the same indication, and the eligibility criteria for the trial. Patients participating in our trials may elect to leave our trials and switch to alternative treatments that are available to them, either commercially or on an expanded access basis, or in other clinical trials. Competing treatments include nucleoside analogs, anthracyclines and hypomethylating agents. Moreover, when one product candidate is evaluated in multiple clinical trials simultaneously, patient enrollment in ongoing trials can be adversely affected by negative results from completed trials.

The results of preclinical studies and clinical trials may not satisfy the requirements of the EMA, FDA or other regulatory agencies.

Prior to receiving approval to commercialize vosaroxin or future product candidates, if any, in Europe, the United States or in other territories, we must demonstrate with substantial evidence from well-controlled clinical trials, to the satisfaction of the EMA, FDA and other regulatory authorities, that such product candidates are safe and effective for their intended uses. The results from preclinical studies and clinical trials can be interpreted in different ways, and based upon a meeting with the FDA held in July 2015, the FDA recommended that we provide additional clinical evidence prior to any regulatory filing for vosaroxin in the United States. Even if we believe preclinical or clinical data from preclinical studies and clinical trials are promising, such data may not be sufficient to support approval by the EMA, FDA and other regulatory authorities.

We rely on third parties to conduct our clinical trials. If these third parties do not successfully carry out their contractual duties or fail to meet expected deadlines, we may be unable to obtain regulatory approval for, or commercialize, vosaroxin.

We rely on third parties, such as contract research organizations, medical institutions, clinical investigators and contract laboratories, to conduct our planned and existing clinical trials for vosaroxin. If the third parties conducting our clinical trials do not perform their contractual duties or obligations, do not meet expected deadlines or need to be replaced, or if the quality or accuracy of the clinical data they obtain is compromised due to the failure to adhere to our clinical trial protocols or for any other reason, we may need to enter into new arrangements with alternative third parties and our clinical trials may be extended, delayed or terminated or may need to be repeated, and we may not be able to obtain regulatory approval for or commercialize the product candidate being tested in such trials.

We may expand our development capabilities in the future, and any difficulties hiring or retaining key personnel or managing this growth could disrupt our operations.

We are highly dependent on the principal members of our development staff. We may expand our research and development capabilities in the future by increasing expenditures in these areas, hiring additional employees and potentially expanding the scope of our current operations. Future growth will require us to continue to implement and improve our managerial, operational and financial systems and continue to retain, recruit and train additional qualified personnel, which may impose a strain on our administrative and operational infrastructure. The competition for qualified personnel in the biopharmaceutical field is intense. We are highly dependent

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on our continued ability to attract, retain and motivate highly qualified management and specialized personnel required for clinical development. Due to our limited resources, we may not be able to effectively manage any expansion of our operations or recruit and train additional qualified personnel. If we are unable to retain key personnel or manage our growth effectively, we may not be able to implement our business plan.

If we are sued for infringing intellectual property rights of third parties, litigation will be costly and time-consuming and could prevent us from developing or commercializing vosaroxin.

Our commercial success depends on not infringing the patents and other proprietary rights of third parties and not breaching any collaboration or other agreements we have entered into with regard to our technologies and product candidates. If a third party asserts that we are using technology claimed in issued and unexpired patents owned or controlled by the third party, we may need to obtain a license, enter into litigation to challenge the validity of the patents or incur the risk of litigation in the event that a third party asserts that we infringe its patents.

If a third party asserts that we infringe its patents or other proprietary rights, we could face a number of challenges that could seriously harm our competitive position, including:

If our competitors develop and market products that are more effective, safer or less expensive than vosaroxin, our commercial opportunities will be negatively impacted.

The life sciences industry is highly competitive, and we face significant competition from many pharmaceutical, biopharmaceutical and biotechnology companies that are researching, developing and marketing products designed to address the treatment of cancer, including AML, MDS and B-cell malignancies. Many of our competitors have significantly greater financial, manufacturing, marketing and drug development resources than we do. Large pharmaceutical companies in particular have extensive experience in the clinical testing of, obtaining regulatory approvals for, and marketing drugs.

We believe that our ability to successfully compete in the marketplace with vosaroxin and any future product candidates, if any, will depend on, among other things:

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Vosaroxin is a small molecule therapeutic that, if approved, will compete with other drugs and therapies currently used for AML, such as nucleoside analogs, anthracyclines, hypomethylating agents, other inhibitors of topoisomerase II, and other novel agents. Additionally, other compounds currently in development could become potential competitors of vosaroxin, if approved for marketing.

If approved, we expect competition for vosaroxin for the treatment of AML and other potential future indications to increase as additional products are developed and approved in various patient populations. If our competitors market products that are more effective, safer or less expensive than vosaroxin or our other future products, if any, or that reach the market sooner we may not achieve commercial success or substantial market penetration. In addition, the biopharmaceutical industry is characterized by rapid change. Products developed by our competitors may render vosaroxin or any future product candidates obsolete.

Our proprietary rights may not adequately protect vosaroxin or future product candidates, if any.

Our commercial success will depend on our ability to obtain patents and maintain adequate protection for vosaroxin and any future product candidates in Europe, the United States and other countries. We own, co-own or have rights to a significant number of issued U.S. and foreign patents and pending U.S. and foreign patent applications. We will be able to protect our proprietary rights from unauthorized use by third parties only to the extent that our proprietary technologies and future products are covered by valid and enforceable patents or are effectively maintained as trade secrets or are subject to marketing exclusivity administered by regulatory authorities.

We apply for patents covering both our technologies and product candidates, as we deem appropriate. However, we may fail to apply for patents on important technologies or product candidates in a timely fashion, or at all. Our existing patents and any future patents we obtain may not be sufficiently broad, valid, or enforceable to prevent others from practicing our technologies or from developing competing products and technologies. In addition, we generally do not exclusively control the patent prosecution of subject matter that we license to or from others. Accordingly, in such cases we are unable to exercise the same degree of control over this intellectual property as we would over our own. Moreover, the patent positions of biopharmaceutical companies are highly uncertain and involve complex legal and factual questions for which important legal principles remain unresolved. As a result, the scope, validity and enforceability of patents can vary from country to country, and can change depending on changes in national and international law, and as such, cannot be predicted with certainty. In addition, we do not know whether:

We also rely on trade secrets to protect some of our technology, especially where we do not believe patent protection is appropriate or obtainable. However, trade secrets are difficult to maintain. While we use reasonable efforts to protect our trade secrets, our or our collaboration partners’ employees, consultants, contractors or scientific and other advisors, or those of our licensors or collaborators, may unintentionally or willfully disclose our proprietary information to competitors. Enforcement of claims that a third party has illegally obtained and is using trade secrets is expensive, time consuming and uncertain. In addition, foreign courts are sometimes less willing than U.S. courts to protect trade secrets. If our competitors independently develop equivalent knowledge, methods and know-how, we would not be able to assert our trade secret protection against them and our business could be harmed.

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The initial composition-of-matter patents covering vosaroxin  expired  in 2015. While we continue to seek additional patent protection for vosaroxin and methods of its manufacture and use, even if vosaroxin is approved by the EMA, FDA or foreign equivalents in other territories, we may not be able to recover our development costs prior to the expiration of any patents that are granted.*

The vosaroxin composition-of-matter is covered by U.S. Patent No. 5,817,669 B2 and its counterpart patents in 43 foreign jurisdictions. This U.S. patent has expired in October 2015, while most of its foreign counterparts have expired in June 2015. We have also been granted  patents relating to vosaroxin compositions, and uses and manufacture of vosaroxin, in the U.S.:

We have been granted  patents relating to vosaroxin compositions, and uses and manufacture of vosaroxin, in Europe:

In addition to the listed United States and European patents, we have been granted similar and related patents in certain other countries, and patent applications are pending in these and other countries, including major markets, throughout the world. In addition, other patents have been granted in the United States and other countries claiming certain technology related to vosaroxin and other methods of use of vosaroxin.

While it is possible that patent term restoration and/or supplemental patent certificates would be available for some of these or other patents we own or control through licenses, we cannot guarantee that such additional protection will be obtained, and the expiration dates described here do not include such term restoration. However, patent expiration dates described here for U.S. patents may reflect patent term adjustments by the United States Patent and Trademark Office or terminal disclaimers over related patents or patent applications.

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We do not know when, if ever, vosaroxin will be approved by the EMA, FDA or other regulatory authorities.  Even if our vosaroxin product is approved for commercial marketing in the future, we may not have sufficient time to commercialize our vosaroxin product to enable us to recover our development costs prior to the expiration of the U.S. and foreign patents covering vosaroxin. We do not know whether patent term extensions and data exclusivity periods will be available in the future for any or all of the patents we own or have licensed. Our obligation to pay royalties to Sumitomo Dainippon Pharma Co., Ltd., the company from which we licensed vosaroxin, may extend beyond the patent expiration, which would further erode the profitability of this product. In addition, our potential obligation to pay RPI royalties pursuant to the Royalty Agreement would also further erode the profitability of this product.

We do not know when, if ever, vosaroxin will be approved by the EMA, FDA or other regulatory authorities.  Even if our vosaroxin product is approved for commercial marketing in the future, we may not have sufficient time to commercialize our vosaroxin product to enable us to recover our development costs prior to the expiration of the U.S. and foreign patents covering vosaroxin. We do not know whether patent term extensions and data exclusivity periods will be available in the future for any or all of the patents we own or have licensed. Our obligation to pay royalties to Sumitomo Dainippon Pharma Co., Ltd., the company from which we licensed vosaroxin, may extend beyond the patent expiration, which would further erode the profitability of this product. In addition, our potential obligation to pay RPI royalties pursuant to the Royalty Agreement would also further erode the profitability of this product.

Any future workforce and expense reductions may have an adverse impact on our internal programs, our ability to hire and retain key personnel and may be distracting to management.

We have, in the past, implemented a number of workforce reductions. Depending on our need for additional funding and expense control, we may be required to implement further workforce and expense reductions in the future. Further workforce and expense reductions could result in reduced progress on our internal programs. In addition, employees, whether or not directly affected by a reduction, may seek future employment with our business partners or competitors. Although our employees are required to sign a confidentiality agreement at the time of hire, the confidential nature of certain proprietary information may not be maintained in the course of any such future employment. Further, we believe that our future success will depend in large part upon our ability to attract and retain highly skilled personnel. We may have difficulty retaining and attracting such personnel as a result of a perceived risk of future workforce and expense reductions. In addition, the implementation of expense reduction programs may result in the diversion of efforts of our executive management team and other key employees, which could adversely affect our business.

We may be subject to damages resulting from claims that we or our employees have wrongfully used or disclosed alleged trade secrets of our employees’ former employers.

Many of our employees were previously employed at biotechnology or pharmaceutical companies, including our competitors or potential competitors. We may be subject to claims that we or our employees have inadvertently or otherwise used or disclosed trade secrets or other proprietary information of their former employers. Litigation may be necessary to defend against these claims. If we fail in defending such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel.

A loss of key personnel or the work product of current or former personnel could hamper or prevent our ability to commercialize vosaroxin, which could severely harm our business. Even if we are successful in defending against these claims, litigation could result in substantial costs and be a distraction to management.

We currently have limited marketing staff and no sales or distribution organization. If we are unable to develop a sales and marketing and distribution capability on our own, by contracting with third parties or through collaborations with marketing partners, we will not be successful in commercializing vosaroxin.

We currently have no sales or distribution capabilities and a limited marketing staff. If we receive favorable feedback from our regulatory discussion with the EMA or FDA and are able to pursue and obtain marketing approval for vosaroxin in Europe or the U.S., we will plan to establish our own sales and marketing organization with technical expertise and supporting distribution capabilities to commercialize vosaroxin in these territories, which will be expensive and time consuming. Any failure or delay in the development of our internal or subcontracted sales, marketing and distribution capabilities would adversely impact the commercialization of these products. We plan to collaborate with third parties that have direct sales forces and established distribution systems in certain territories as part of the commercialization of vosaroxin. To the extent that we enter into co-promotion or other licensing arrangements, our product revenue is likely to be lower than if we marketed or sold vosaroxin directly. In addition, any revenue we receive will depend upon the efforts of third parties, which may not be successful and are only partially within our control. If we are unable to enter into such arrangements on acceptable terms or at all, we may not be able to successfully commercialize vosaroxin. If we are not successful in commercializing vosaroxin or our future product candidates, if any, either on our own or through collaborations with one or more third parties, our future product revenue will suffer and we may incur significant additional losses.

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We depend on various consultants and advisors for the success and continuation of our development efforts.

We work extensively with various consultants and advisors, who provide advice and/or services in various business and development functions, including clinical development, operations and strategy, regulatory matters, biostatistics, legal and finance. The potential success of our drug development programs depends, in part, on continued collaborations with certain of these consultants and advisors. Our consultants and advisors are not our employees and may have commitments and obligations to other entities that may limit their availability to us. We do not know if we will be able to maintain such relationships or that such consultants and advisors will not enter into other arrangements with competitors, any of which could have a detrimental impact on our development objectives and our business.

If conflicts of interest arise between our current or future licensees or collaboration partners, if any, and us, any of them may act in their self-interest, which may be adverse to our interests.

If a conflict of interest arises between us and one or more of our current or potential future licensees or collaboration partners, if any, they may act in their own self-interest or otherwise in a way that is not in the interest of our company or our stockholders. Biogen, Takeda, or potential future licensees or collaboration partners, if any, are conducting or may conduct product development efforts within the disease area that is the subject of a license or collaboration with our company. In current or potential future licenses or collaborations, if any, we have agreed or may agree not to conduct, independently or with any third party, any research that is competitive with the research conducted under our licenses or collaborations. Our licensees or collaboration partners, however, may develop, either alone or with others, products in related fields that are competitive with the product candidates that are the subject of these licenses or collaborations. Competing products, either developed by our licensees or collaboration partners or to which our licensees or collaboration partners have rights, may result in their withdrawal of support for a product candidate covered by the license or collaboration agreement.

If one or more of our current or potential future licensees or collaboration partners, if any, were to breach or terminate their license or collaboration agreements with us or otherwise fail to perform their obligations thereunder in a timely manner, the preclinical or clinical development or commercialization of the affected product candidates could be delayed or terminated. We do not know whether our licensees or collaboration partners will pursue alternative technologies or develop alternative product candidates, either on their own or in collaboration with others, including our competitors, as a means for developing treatments for the diseases targeted by licenses or collaboration agreements with our company.

Compliance with changing regulation of corporate governance and public disclosure may result in additional expenses.

Changing laws, regulations and standards relating to corporate governance and public disclosure may create uncertainty regarding compliance matters. New or changed laws, regulations and standards are subject to varying interpretations in many cases. As a result, their application in practice may evolve over time. We are committed to maintaining high standards of corporate governance and public disclosure. Complying with evolving interpretations of new or changed legal requirements may cause us to incur higher costs as we revise current practices, policies and procedures, and may divert management time and attention from potential revenue-generating activities to compliance matters. If our efforts to comply with new or changed laws, regulations and standards differ from the activities intended by regulatory or governing bodies due to ambiguities related to practice, our reputation may also be harmed. Further, our board members, chief executive officer and chief financial officer could face an increased risk of personal liability in connection with the performance of their duties. As a result, we may have difficulty attracting and retaining qualified board members and executive officers, which could harm our business.

Raising funds through lending arrangements or revenue participation agreements may restrict our operations or produce other adverse results.

Our loan and security agreement, or the Loan Agreement, with Western Alliance Bank and Solar Capital or collectively, the Lenders, contains a variety of affirmative covenants, including, without limitation, certain information delivery requirements, obligations to maintain certain insurance and certain notice requirements. Additionally, the Company is bound by certain negative covenants setting forth actions that are not permitted to be taken during the term of the Loan Agreement without the Lenders’ consent, including, without limitation, incurring certain additional indebtedness, making certain asset dispositions, entering into certain mergers, acquisitions or other business combination transactions or incurring any non-permitted lien or other encumbrance on the Company’s assets. Upon the occurrence of an event of default under the Loan Agreement (subject to cure periods for certain events of default), all amounts owed by the Company thereunder would begin to bear interest at a rate that is 5.0% higher than the rate that would otherwise be applicable and may be declared immediately due and payable by the Collateral Agent. Events of default under the Loan Agreement include, among other things, the following: the occurrence of certain bankruptcy events; the failure to make payments under the Loan Agreement when due; the occurrence of a material impairment on the Collateral Agent’s security interest over the collateral, a material adverse change in the business, operations or condition (financial or otherwise) of the Company or material impairment of the

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prospect of repayment of the obligations under the Loan Agreement; the occurrence of a default under certain other agreements entered into by the Company; the rendering of certain types of judgments against the Company; the revocation of certain government approvals of the Company; any breach by the Company of any covenant (subject to cure periods for certain covenants) made in the Loan Agreement; and the failure of any representation or warranty made by the Company in connection with the Loan Agreement to be correct in all material respects when made.

The Collateral Agent, for the benefit of the Lenders, has a perfected security interest in substantially all of the Company’s property, rights and assets, except for intellectual property, to secure the payment of all amounts owed to the Lenders under the Loan Agreement. Upon marketing approval of vosaroxin, the Collateral Agent, for the benefit of the Lenders, will also have a perfected security interest in the Company’s intellectual property rights relating to vosaroxin.

In addition, following the purchase of the revenue participation right by RPI, we are required to pay RPI a specified percentage of any net sales of vosaroxin. If we fail to make timely payments due to RPI under the Royalty Agreement, RPI may require us to repurchase the revenue participation right. As collateral for these payments, we granted RPI a security interest in certain of our assets, including our intellectual property related to vosaroxin, as detailed above.

We are exposed to risks related to foreign currency exchange rates and European sovereign debt.

Some of our costs and expenses are denominated in foreign currencies. Most of our foreign expenses are associated with activities related to the VALOR trial which occurred outside of the United States, and in particular in Western Europe. When the U.S. dollar weakens against the Euro or British pound, the U.S. dollar value of the foreign currency denominated expense increases, and when the U.S. dollar strengthens against the Euro or British pound, the U.S. dollar value of the foreign currency denominated expense decreases. Consequently, changes in exchange rates, and in particular a weakening of the U.S. dollar, may adversely affect our results of operations. We have and may continue to purchase certain European currencies or highly-rated investments denominated in such currencies to manage the risk of future movements in foreign exchange rates that would affect such payables, in accordance with our investment policy. However, there is no guarantee that the related gains and losses will substantially offset each other, and we may be subject to significant exchange gains or losses as currencies fluctuate from quarter to quarter.

In addition, the recent sovereign debt crisis concerning certain European countries and related European financial restructuring efforts has and may continue to cause the value of the Euro to deteriorate. Such deterioration could adversely impact any investments we hold that are denominated in Euros. Rating agency downgrades on European sovereign debt and any potential default of European government issuers further contribute to this uncertainty. Should governments default on their obligations, we may experience loss of principal on any investments in European sovereign debt.

Our facilities are located near known earthquake fault zones, and the occurrence of an earthquake or other catastrophic disaster, or interruption by man-made problems such as network security breaches, viruses or terrorism, could cause damage to our facilities and equipment, which could require us to cease or curtail operations.

Our facilities are located in the San Francisco Bay Area near known earthquake fault zones and are vulnerable to significant damage from earthquakes. We are also vulnerable to damage from other types of disasters, including fires, floods, power loss, communications failures and similar events. Despite the implementation of network security measures, our networks also may be vulnerable to computer viruses, break-ins and similar disruptions.  We rely on information technology systems to operate our business and to communicate among our workforce and with third parties. If any disruption were to occur, whether caused by a natural disaster or by manmade problems, our ability to operate our business at our facilities may be seriously or completely impaired and our data could be lost or destroyed.

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Risks Related to Our Industry

The regulatory approval process is expensive, time consuming and uncertain and may prevent us from obtaining approval for the commercialization of vosaroxin.

The research, testing, manufacturing, selling and marketing of product candidates are subject to extensive regulation by the FDA and other regulatory authorities in the United States and other countries, which regulations differ from country to country. Neither we nor our present or potential future collaboration or licensing partners, if any, are permitted to market our product candidates in Europe or the United States until we receive approval of an MAA or NDA for these respective territories, or in any other country without the equivalent marketing approval from such country. We have not received marketing approval for vosaroxin in any jurisdiction. In addition, failure to comply with EMA, FDA and other applicable U.S. and foreign regulatory requirements may subject us to administrative or judicially imposed sanctions, including warning letters, civil and criminal penalties, injunctions, product seizure or detention, product recalls, total or partial suspension of production, and refusal to approve pending MAAs, NDAs, supplements to approved MAAs, NDAs or their equivalents in other territories.

Regulatory approval of an MAA or NDA or their equivalent in other territories is not guaranteed, and the approval process is expensive, uncertain and may take several years. Furthermore, the development process for oncology products may take longer than in other therapeutic areas. Regulatory authorities have substantial discretion in the drug approval process. Despite the time and expense exerted, failure can occur at any stage, and we could encounter problems that cause us to abandon clinical trials or to repeat or perform additional preclinical studies and clinical trials. The number of preclinical studies and clinical trials that will be required for marketing approval varies depending on the drug candidate, the disease or condition that the drug candidate is designed to address, and the regulations applicable to any particular drug candidate. In particular, the VALOR trial failed to meet its primary endpoint, and in July 2015, the FDA recommended that we provide additional clinical evidence before any regulatory filing for vosaroxin for the treatment of AML in the United States.

The EMA, FDA or other foreign regulatory authority can delay, limit or deny approval of a drug candidate for many reasons, including:

We may be subject to costly claims related to our clinical trials and may not be able to obtain adequate insurance.

Because we conduct clinical trials in humans, we face the risk that the use of vosaroxin or future product candidates, if any, will result in adverse side effects. We cannot predict the possible harms or side effects that may result from our clinical trials. Although we have clinical trial liability insurance, our insurance may be insufficient to cover any such events. We do not know whether we will be able to continue to obtain clinical trial coverage on acceptable terms, or at all. We may not have sufficient resources to pay for any liabilities resulting from a claim excluded from, or beyond the limit of, our insurance coverage. There is also a risk that third parties that we have agreed to indemnify could incur liability. Any litigation arising from our clinical trials, even if we were ultimately successful, would consume substantial amounts of our financial and managerial resources and may create adverse publicity.

Even if we receive regulatory approval to sell vosaroxin, the market may not be receptive to vosaroxin.

Even if vosaroxin obtains regulatory approval, it may not gain market acceptance among physicians, patients, healthcare payors and/or the medical community. We believe that the degree of market acceptance will depend on a number of factors, including:

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For example, the potential toxicity of single and repeated doses of vosaroxin has been explored in a number of animal studies that suggest the dose-limiting toxicities in humans receiving vosaroxin may be similar to some of those observed with approved cytotoxic agents, including reversible toxicity to bone marrow cells, the gastrointestinal system and other systems with rapidly dividing cells. In our Phase 1, Phase 2 and VALOR clinical trials of vosaroxin, we have witnessed the following side effects, irrespective of causality, ranging from mild to more severe: lowered white blood cell count that may lead to a serious or possibly life-threatening infection, hair loss, mouth sores, fatigue, nausea with or without vomiting, lowered platelet count, which may lead to an increase in bruising or bleeding, lowered red blood cell count (anemia), weakness, tiredness, shortness of breath, diarrhea and intestinal blockage.

If vosaroxin fails to achieve market acceptance, due to unacceptable side effects or any other reasons, we may not be able to generate significant revenue or to achieve or sustain profitability.

Even if we receive regulatory approval for vosaroxin, we will be subject to ongoing EMA, FDA and other regulatory obligations and continued regulatory review, which may result in significant additional expense and limit our ability to commercialize vosaroxin.

Any regulatory approvals that we or our potential future collaboration partners receive for vosaroxin or our future product candidates, if any, may also be subject to limitations on the indicated uses for which the product may be marketed or contain requirements for potentially costly post-marketing trials. In addition, even if approved, the labeling, packaging, adverse event reporting, storage, advertising, promotion and recordkeeping for any product will be subject to extensive and ongoing regulatory requirements. The subsequent discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, may result in restrictions on the marketing of the product, and could include withdrawal of the product from the market.

Regulatory policies may change and additional government regulations may be enacted that could prevent or delay regulatory approval of our product candidates. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in Europe, the United States or other territories. If we are not able to maintain regulatory compliance, we might not be permitted to market vosaroxin or our future products and we may not achieve or sustain profitability.

The coverage and reimbursement status of newly approved drugs is uncertain, and failure to obtain adequate coverage and reimbursement could limit our ability to market vosaroxin and decrease our ability to generate revenue.

There is significant uncertainty related to the third party coverage and reimbursement of newly approved drugs both nationally and internationally. The commercial success of vosaroxin and our future products, if any, in both domestic and international markets depends on whether third-party coverage and reimbursement is available for the ordering of our future products by the medical profession for use by their patients. Medicare, Medicaid, health maintenance organizations and other third-party payors are increasingly attempting to manage healthcare costs by limiting both coverage and the level of reimbursement of new drugs and, as a result, they may not cover or provide adequate payment for our future products. These payors may not view our future products as cost-effective, and reimbursement may not be available to consumers or may not be sufficient to allow our future products to be marketed on a competitive basis. Likewise, legislative or regulatory efforts to control or reduce healthcare costs or reform government healthcare programs could result in lower prices or rejection of our future products. Changes in coverage and reimbursement policies or healthcare cost containment initiatives that limit or restrict reimbursement for our future products may reduce any future product revenue.

Failure to obtain regulatory approval in foreign jurisdictions will prevent us from marketing vosaroxin abroad.

We intend to market vosaroxin in international markets either directly or through a potential future collaboration partner, if any. In order to market vosaroxin in the European Union, Canada and many other foreign jurisdictions, we or a potential future collaboration partner must obtain separate regulatory approvals. We have, and potential future collaboration partners may have, had limited interactions with foreign regulatory authorities, and the approval procedures vary among countries and can involve additional testing at significant cost. The time required to obtain approval may differ from that required to obtain FDA approval. Approval by the  FDA does not ensure approval by regulatory authorities in other countries, and approval by one foreign regulatory authority does not ensure approval by regulatory authorities in other foreign countries or by the FDA. The foreign regulatory approval processes may include all of the risks associated with obtaining FDA approval. We or a potential future collaboration partner may not obtain foreign

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regulatory approvals on a timely basis, if at all. We or a potential future collaboration partner may not be able to file for regulatory approvals and may not receive necessary approvals to commercialize vosaroxin or any other future products in any market.

Foreign governments often impose strict price controls, which may adversely affect our future profitability.

We intend to seek approval to market vosaroxin in Europe, the United States and other foreign jurisdictions either directly or through one or more potential future collaboration partners. If we or a potential future collaboration partner obtain approval in one or more foreign jurisdictions, we or the potential future collaboration partner will be subject to rules and regulations in those jurisdictions relating to vosaroxin. In some foreign countries, particularly in the European Union, prescription drug pricing is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take considerable time after the receipt of marketing approval for a drug candidate. To obtain reimbursement or pricing approval in some countries, we or a potential future collaboration partner may be required to conduct a clinical trial that compares the cost-effectiveness of vosaroxin to other available therapies. If reimbursement of vosaroxin is unavailable or limited in scope or amount, or if pricing is set at unsatisfactory levels, we may be unable to achieve or sustain profitability.

We may incur significant costs complying with environmental laws and regulations, and failure to comply with these laws and regulations could expose us to significant liabilities.

We, through third-party contractors, use hazardous chemicals and radioactive and biological materials in our business and are subject to a variety of federal, state, regional and local laws and regulations governing the use, generation, manufacture, storage, handling and disposal of these materials. Although we believe our safety procedures for handling and disposing of these materials and waste products comply with these laws and regulations, we cannot eliminate the risk of accidental injury or contamination from the use, storage, handling or disposal of hazardous materials. In the event of contamination or injury, we could be held liable for any resulting damages, and any liability could significantly exceed our insurance coverage, which is limited for pollution cleanup and contamination.

Risks Related to Our Common Stock

The price of our common stock may continue to be volatile, and the value of an investment in our common stock may decline.*

In the three months ended March 31, 2016, our common stock traded as low as $0.45 and as high as $0.95, and in 2015, traded as low as $0.74 and as high as $3.72. Factors that could cause continued volatility in the market price of our common stock include, but are not limited to:

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If we fail to maintain compliance with the continued listing requirements of The NASDAQ Capital Market, our common stock may be delisted and the price of our common stock and our ability to access the capital markets could be negatively impacted.

Our common stock currently trades on The NASDAQ Capital Market under the symbol "SNSS." This market has continued listing standards that we must comply with in order to maintain the listing of our common stock. The continued listing standards include, among others, a minimum bid price requirement of $1.00 per share and any of: (i) a minimum stockholders' equity of $2.5 million; (ii) a market value of listed securities of at least $35.0 million; or (iii) net income from continuing operations of $500,000 in the most recently completed fiscal year or in the two of the last three fiscal years. Our results of operations and fluctuating stock price directly impact our ability to satisfy these continued listing standards and recently our common stock has traded below the $1.00 per share minimum. If the closing bid price our common stock falls below the $1.00 minimum for at least 30 consecutive trading days, or in the event we are unable to maintain one of the alternative continued listing standards, our common stock may be subject to delisting from The NASDAQ Capital Market.

On November 24, 2015 we had received a letter from the Listing Qualifications Department of The NASDAQ Stock Market, or the Staff, notifying us that, for 30 consecutive business days, the bid price for our common stock had closed below the minimum $1.00 per share requirement, or the Bid Price Requirement, for continued inclusion on The NASDAQ Capital Market pursuant to NASDAQ Listing Rules. In accordance with NASDAQ Listing Rules, we were given 180 calendar days, or until May 23, 2016, to regain compliance. To regain compliance, the bid price of our common stock needed to close at or above $1.00 for at least 10 consecutive business days at any time prior to May 23, 2016. If we do not regain compliance with NASDAQ Listing Rule 5550(a)(2) by May 23, 2016, but meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The NASDAQ Capital Market, with the exception of the Bid Price Requirement, and provide written notice of our intention to cure the deficiency during the second compliance period, by effecting a reverse stock split, if necessary, we will be granted an additional 180 calendar day compliance period. If we fail to regain compliance during the grace period, our common stock could be subject to delisting.

If we are delisted, we would expect our common stock to be traded in the over-the-counter market, which could adversely affect the liquidity of our common stock. Additionally, we could face significant material adverse consequences, including:

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Provisions of our charter documents or Delaware law could delay or prevent an acquisition of our company, even if the acquisition would be beneficial to our stockholders, and could make it more difficult to change management.

Provisions of our amended and restated certificate of incorporation and amended and restated bylaws may discourage, delay or prevent a merger, acquisition or other change in control that stockholders might otherwise consider favorable, including transactions in which stockholders might otherwise receive a premium for their shares. In addition, these provisions may frustrate or prevent any attempt by our stockholders to replace or remove our current management by making it more difficult to replace or remove our board of directors. These provisions include:

In addition, Delaware law prohibits a publicly held Delaware corporation from engaging in a business combination with an interested stockholder, generally a person who, together with its affiliates, owns or within the last three years has owned 15% of our voting stock, for a period of three years after the date of the transaction in which the person became an interested stockholder, unless the business combination is approved in a prescribed manner. Accordingly, Delaware law may discourage, delay or prevent a change in control of our company.

Provisions in our charter documents and provisions of Delaware law could limit the price that investors are willing to pay in the future for shares of our common stock.

We have never paid dividends on our capital stock and we do not anticipate paying any cash dividends in the foreseeable future.

We have never declared or paid cash dividends on our capital stock. We do not anticipate paying any cash dividends on our capital stock in the foreseeable future. In addition, under the terms of our Loan Agreement with the Lenders, we are precluded from paying cash dividends without the prior written consent of the Lenders. We currently intend to retain all available funds and any future earnings to fund the development and growth of our business. As a result, capital appreciation, if any, of our common stock will be our stockholders’ sole source of gain for the foreseeable future.

We are at risk of securities class action litigation.

In the past, securities class action litigation has often been brought against a company following a decline in the market price of its securities. This risk is especially relevant for us because biotechnology companies have experienced greater than average stock price volatility in recent years. These broad market fluctuations may adversely affect the trading price or liquidity of our common stock. In the past, when the market price of a stock has been volatile, holders of that stock have sometimes instituted securities class action litigation against the issuer. If any of our stockholders were to bring such a lawsuit against us, we could incur substantial costs defending the lawsuit and the attention of our management would be diverted from the operation of our business.

None.

None.

Not applicable.

None.

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A list of exhibits filed with this report or incorporated herein by reference is found in the Exhibit Index immediately following the signature page of this report.

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SIGNATURE

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

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EXHIBIT INDEX

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