requires the Company to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.

ing those related to the useful lives of property and equipment, and assumptions used for purposes of determining stock-based compensation, income taxes, and the fair value of the derivative and warrant liability, among others. The Company bases its estimates on historical experience and on various other assumptions that it believes to be reasonable, the results of which form the basis for making judgments about the carrying value of assets and liabilities.

the Company to concentrations of credit risk consist principally of cash on deposit with multiple financial institutions, the balances of which frequently exceed insured limits.

ents with an original maturity of months or less to be cash equivalents.

zed gains and losses included in other income (expense) on the statements of operations. The securities primarily consist of certificates of deposit, U.S. Treasury securities and U.S. government-sponsored agency securities. As of and respectively, the Company held marketable securities and long-term investments with an aggregate fair value of million and million that contained aggregate unrealized losses of and respectively. These marketable securities and long-term investments have been in a continuous unrealized loss position for less than months and the Company expects these investments to fully recovery prior to their maturity.  

depreciation and amortization. Costs of renewals and improvements that extend the useful lives of the assets are capitalized. Maintenance and repairs are expensed as incurred. Depreciation is determined on a straight-line basis over the estimated useful lives of the assets, which generally range from to years. Leasehold improvements are amortized over the shorter of the useful life of the asset or the term of the related lease. Upon retirement or disposition of assets, the costs and related accumulated depreciation and amortization are removed from the accounts with the resulting gains or losses, if any, reflected in results of operations.

ed over the life of the respective financing arrangement using the effective interest method.

may

share of future revenue if related product candidates reach commercialization. Costs under these supply arrangements, if any, are expensed as incurred (Note H).

impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets not be recoverable. When such events occur, the Company compares the carrying amounts of the assets to their undiscounted expected future cash flows. If the undiscounted cash flows are insufficient to recover the carrying values, an impairment loss is recorded for the difference between the carrying values and fair values of the asset. such impairment occurred for the years ended  and

received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, based on the Company’s principal or, in absence of a principal, most advantageous market for the specific asset or liability.

three

equent to their initial measurement. The hierarchy requires the Company to use observable inputs when available, and to minimize the use of unobservable inputs, when determining fair value. The tiers are defined as follows:

ical trials and related clinical manufacturing, costs of drug development, costs of materials and supplies, facilities cost, overhead costs, regulatory and compliance costs, and fees paid to consultants and other entities that conduct certain research and development activities on the Company’s behalf. Costs incurred in research and development are expensed as incurred.

expenses are recognized as expense in the statements of operations as the Company receives the related goods or services.

expenses on the statements of operations.

as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled. Valuation allowances are recorded to reduce deferred tax assets to the amount the Company believes is more likely than not to be realized.

t the tax position will be upheld on examination by the taxing authorities based on the merits of the position. The Company recognizes interest and penalties, if any, related to unrecognized income tax uncertainties in income tax expense. The Company did not have any accrued interest or penalties associated with uncertain tax positions as of  and 

the Company is no longer subject to U.S. federal and state and local income tax examinations for years prior to although carryforward attributes that were generated prior to still be adjusted upon examination by the Internal Revenue Service if used in a future period. No income tax returns are currently under examination by taxing authorities.

d directors based on the estimated fair values of the awards as of the grant date. The Company records the value of the portion of the award that is ultimately expected to vest as expense over the requisite service period. The Company also accounts for equity instruments issued to non-employees using a fair value approach under Accounting Standards Codification ("ASC") subtopic - The Company values equity instruments and stock options granted using the Black-Scholes option pricing model. The value of non-employee stock-based compensation is subject to periodic adjustments as the underlying equity instruments vest and is recognized as an expense over the term of the related financing or the period over which services are received.

two

entitle the holders to participate in dividends and earnings of the Company. The -class method requires earnings for the period to be allocated between common stock and participating securities based upon their respective rights to receive distributed and undistributed earnings. Holders of each series of the Company’s redeemable convertible preferred stock are entitled to participate in distributions, when and if declared by the board of directors, that are made to common stockholders and, as a result, are considered participating securities.

ilable and regularly reviewed by the chief operating decision maker in deciding how to allocate resources and in assessing performance. The Company’s chief operating decision maker (CODM) is its Chief Executive Officer. The Company views its operations and manages its business as a single operating and reporting segment. All assets of the Company were held in the United States as of and 

April

5,

2012,

JOBS Act”) into law. The JOBS Act contains provisions that, among other things, reduce certain reporting requirements for an emerging growth company. As an emerging growth company, the Company elect to adopt new or revised accounting standards when they become effective for non-public companies, which typically is later than public companies must adopt the standards. The Company has elected not to take advantage of the extended transition period afforded by the JOBS Act and, as a result, will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for non-emerging growth companies.

June

2014,

issued ASU - (Topic (“ASU - The amendments require that a performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. ASU - is effective for annual periods and interim periods within those annual periods beginning after Entities apply ASU - either (a) prospectively to all awards granted or modified after the effective date or (b) retrospectively to all awards with performance targets that are outstanding as of the beginning of the earliest annual period presented in the financial statements and to all new or modified awards thereafter. The Company prospectively adopted ASU - effective The adoption of ASU - did not have a material impact on the financial statements as the Company does not have any performance-based awards whereby performance could be achieved after the requisite service period.

August

2014,

2014

15,

(“ASU - which amends ASC Subtopic - to provide guidance about management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related disclosures. Specifically, the amendments provide a definition of the term “substantial doubt,” require an evaluation every reporting period, provide principles for considering the mitigating effect of management’s plans, require certain disclosures when substantial doubt is alleviated as a result of consideration of management’s plans, require an express statement and other disclosures when substantial doubt is not alleviated and require an assessment for a period of year after the date that financial statements are issued. ASU - is effective for fiscal years ending after and for annual periods and interim periods thereafter.

2014

15

’s financial statements as the Company determined there was no substantial doubt about its ability to continue as a going concern as of

January

2015,

2015

01,

, which eliminates from GAAP the concept of extraordinary items, stating that the concept causes uncertainty because it is unclear when an item should be considered both unusual and infrequent and users do not find the classification and presentation necessary to identify those events and transactions. ASU - is effective for fiscal years, and interim periods within those fiscal years, beginning after The Company adopted ASU - effective The adoption of ASU - did not have a material impact on the Company’s financial statements as the Company had no extraordinary and/or unusual items recorded in prior periods.

April

2015,

2015

03,

d to a recognized debt liability be presented in the balance sheet as direct deduction from the carrying amount of that debt liability, consistent with the presentation of debt discounts. This guidance is effective for financial statements issued for fiscal years beginning after and interim periods within those fiscal years. The adoption of ASU - reduced the Company’s assets and liabilities by the amount of the debt issuance costs, which was million at This reclassification had no effect on reported net loss or cash flows.

May

2014,

606,

("ASC which amends the guidance in former ASC , and becomes effective beginning The Company does not currently expect this standard to have a material effect on its financial statements upon adoption since the Company is not generating revenue at this time.

November

2015,

2015

17,

(“ASU - which requires that deferred tax liabilities and assets be classified as noncurrent in a classified statement of financial position. This update applies to all entities that present a classified statement of financial position. This guidance is effective for financial statements issued for fiscal years beginning after and interim periods within those fiscal years. The Company does not currently expect this standard to have a material effect on its financial statements and disclosures upon adoption since the Company currently maintains a full valuation allowance.

January

2016,

2016

01,

(“ASU - which provides several updates related to Topic - This update applies to all entities that hold financial assets or owe financial liabilities. This guidance is effective for financial statements issued for fiscal years beginning after and interim periods within those fiscal years. The Company is currently evaluating the impact of the adoption of ASU - on its financial statements and disclosures.

February

2016,

2016

02,

(“ASU - which requires lessees to recognize assets and liabilities for operating leases with lease terms greater than months in the balance sheet. The update also requires improved disclosures to help users of financial statements better understand the amount, timing and uncertainty of cash flows arising from leases. ASU - is effective for fiscal years beginning after including interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of the adoption of ASU - on its financial statements and disclosures.

March

2016,

2016

06,

(“ASU - which clarifies the requirements for assessing whether contingent call and put options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. ASU - is effective for fiscal years beginning after including interim periods within those fiscal years, with early adoption permitted. The Company does not currently expect this standard to have a material effect on its financial statements and disclosures upon adoption.

rch the FASB issued ASU - (“ASU - which simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU - is effective for fiscal years beginning after including interim periods within those fiscal years, with early adoption permitted. The Company does not currently expect this standard to have a material effect on its financial statements and disclosures upon adoption.

  the FASB issued ASU - (“ASU - which addresses specific cash flow issues with the objective of reducing the existing diversity in practice. This update applies to all entities that are required to present a statement of cash flows under Topic This guidance is effective for financial statements issued for fiscal years beginning after and interim periods within those fiscal years. The Company is currently evaluating the impact of the adoption of ASU - on its financial statements and disclosures.