Document and Entity Information
Document and Entity Information - USD ($) | 12 Months Ended | ||
Dec. 31, 2015 | Mar. 21, 2016 | Jun. 30, 2015 | |
Document and Entity Information [Abstract] | |||
Entity Registrant Name | Global Blood Therapeutics, Inc. | ||
Entity Central Index Key | 1,629,137 | ||
Document Type | 10-K | ||
Document Fiscal Period Focus | FY | ||
Document Period End Date | Dec. 31, 2015 | ||
Document Fiscal Year Focus | 2,015 | ||
Current Fiscal Year End Date | --12-31 | ||
Entity Filer Category | Non-accelerated Filer | ||
Amendment Flag | false | ||
Entity Common Stock, Shares Outstanding | 30,527,075 | ||
Entity Public Float | $ 0 | ||
Entity Well-known Seasoned Issuer | No | ||
Entity Voluntary Filers | No | ||
Entity Current Reporting Status | Yes |
Balance Sheets
Balance Sheets - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 |
Current assets: | ||
Cash and cash equivalents | $ 148,502 | $ 52,069 |
Prepaid expenses | 1,222 | 1,135 |
Other assets, current | 1,096 | 389 |
Total current assets | 150,820 | 53,593 |
Property and equipment, net | 2,114 | 2,023 |
Restricted cash | 140 | 140 |
Total assets | 153,074 | 55,756 |
Current liabilities: | ||
Accounts payable | 3,361 | 541 |
Payable due to related party | 0 | 14 |
Accrued liabilities | 4,400 | 948 |
Accrued compensation | 2,242 | 847 |
Other liabilities, current | 720 | 187 |
Total current liabilities | 10,723 | 2,537 |
Other liabilities, noncurrent | 1,556 | 384 |
Total liabilities | $ 12,279 | $ 2,921 |
Commitments and contingencies (Note 12) | ||
Redeemable convertible preferred stock, $0.001 par value: zero and 69,363,168 shares authorized at December 31, 2015 and 2014, respectively; zero and 69,113,168 shares issued and outstanding at December 31, 2015 and 2014, respectively; aggregate liquidation preference of zero and $103,289 at December 31, 2015 and 2014, respectively. | $ 0 | $ 102,161 |
Stockholders’ equity (deficit): | ||
Preferred stock, $0.001 par value, 5,000,000 and zero shares authorized at December 31, 2015 and 2014, respectively, and none issued and outstanding as of December 31, 2015 and 2014. | 0 | 0 |
Common stock, $0.001 par value, 150,000,000 and 94,000,000 shares authorized at December 31, 2015 and 2014, respectively; 29,359,800 and 1,954,488 shares issued and outstanding at December 31, 2015 and 2014, respectively. | 29 | 2 |
Additional paid-in capital | 239,231 | 0 |
Accumulated deficit | (98,465) | (49,328) |
Total stockholders’ equity (deficit) | 140,795 | (49,326) |
Total liabilities, redeemable convertible preferred stock and stockholders’ equity (deficit) | $ 153,074 | $ 55,756 |
Condensed Balance Sheets (Paren
Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 |
Temporary equity: | ||
Redeemable convertible preferred stock, par value (usd per share) | $ 0.001 | $ 0.001 |
Redeemable convertible preferred stock, shares authorized (shares) | 0 | 69,363,168 |
Redeemable convertible preferred stock, shares issued (shares) | 0 | 69,113,168 |
Redeemable convertible preferred stock, shares outstanding (shares) | 0 | 69,113,168 |
Aggregate liquidation preference | $ 0 | $ 103,289 |
Stockholders’ equity (deficit): | ||
Preferred stock, par value (in usd per share) | $ 0.001 | $ 0.001 |
Preferred stock, shares authorized | 5,000,000 | 0 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Common stock, par value (in usd per share) | $ 0.001 | $ 0.001 |
Common stock, shares authorized | 150,000,000 | 94,000,000 |
Common stock, shares issued | 29,359,800 | 1,954,488 |
Common stock, shares outstanding | 29,359,800 | 1,954,488 |
Statements of Operations and Co
Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Operating expenses: | |||
Research and development | $ 36,657 | $ 16,324 | $ 12,855 |
General and administrative | 9,671 | 3,855 | 2,309 |
Related party expenses | 65 | 332 | 499 |
Total operating expenses | 46,393 | 20,511 | 15,663 |
Loss from operations | (46,393) | (20,511) | (15,663) |
Change in fair value of Series A redeemable convertible preferred stock liability | 0 | (297) | (2,455) |
Interest income | 33 | 1 | 2 |
Net loss | (46,360) | (20,807) | (18,116) |
Comprehensive loss | (46,360) | (20,807) | (18,116) |
Net loss attributable to common stockholders | $ (50,540) | $ (23,772) | $ (19,851) |
Net loss per share attributable to common stockholders, basic and diluted (usd per share) | $ (3.95) | $ (14.20) | $ (16.14) |
Weighted-average number of shares used in computing net loss per share attributable to common stockholders, basic and diluted (shares) | 12,806,697 | 1,673,919 | 1,230,241 |
Statements of Redeemable Conver
Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) Statement - USD ($) $ in Thousands | Total | Series A | Series B | Common Stock | Additional Paid-In Capital | Accumulated Deficit |
Balance at, at Dec. 31, 2012 | $ 9,451 | |||||
Balance at, (shares) at Dec. 31, 2012 | 13,663,168 | |||||
Increase (Decrease) in Redeemable Convertible Preferred Stock | ||||||
Issuance of redeemable convertible preferred stock, net of issuance costs | $ 15,235 | |||||
Issuance of stock (in shares) | 15,250,000 | |||||
Remeasurement of fair value and settlement of Series A redeemable convertible preferred stock liability | $ 1,804 | |||||
Accretion of redeemable convertible preferred stock to redemption value | 1,735 | |||||
Balance at, at Dec. 31, 2013 | $ 28,225 | |||||
Balance at, (shares) at Dec. 31, 2013 | 28,913,168 | |||||
Balance at, at Dec. 31, 2012 | $ (9,349) | $ 1 | $ 444 | $ (9,794) | ||
Balance at, (shares) at Dec. 31, 2012 | 971,418 | |||||
Increase (Decrease) in Stockholders' Deficit | ||||||
Remeasurement of fair value and settlement of Series A redeemable convertible preferred stock liability | 3,081 | 3,081 | ||||
Accretion of redeemable convertible preferred stock to redemption value | (1,735) | (1,598) | (137) | |||
Vesting of restricted stock purchase | 6 | 6 | ||||
Vesting of restricted stock purchase (shares) | 412,386 | |||||
Common stock issued on exercise of stock options | 1 | 1 | ||||
Common stock issued on exercise of stock options (shares) | 4,285 | |||||
Stock-based compensation expense | 138 | 138 | ||||
Net loss | (18,116) | (18,116) | ||||
Balance at, at Dec. 31, 2013 | (25,974) | $ 1 | 2,072 | (28,047) | ||
Balance at, (shares) at Dec. 31, 2013 | 1,388,089 | |||||
Increase (Decrease) in Redeemable Convertible Preferred Stock | ||||||
Issuance of redeemable convertible preferred stock, net of issuance costs | $ 20,591 | $ 47,854 | ||||
Issuance of stock (in shares) | 21,000,000 | 19,200,000 | ||||
Remeasurement of fair value and settlement of Series A redeemable convertible preferred stock liability | 2,526 | |||||
Accretion of redeemable convertible preferred stock to redemption value | 2,965 | |||||
Balance at, at Dec. 31, 2014 | $ 102,161 | $ 54,273 | $ 47,888 | |||
Balance at, (shares) at Dec. 31, 2014 | 69,113,168 | 49,913,168 | 19,200,000 | |||
Increase (Decrease) in Stockholders' Deficit | ||||||
Accretion of redeemable convertible preferred stock to redemption value | $ (2,965) | (2,491) | (474) | |||
Vesting of restricted stock purchase | 21 | $ 1 | 20 | |||
Vesting of restricted stock purchase (shares) | 411,333 | |||||
Common stock issued on exercise of stock options | 49 | 49 | ||||
Common stock issued on exercise of stock options (shares) | 155,066 | |||||
Stock-based compensation expense | 350 | 350 | ||||
Net loss | (20,807) | (20,807) | ||||
Balance at, at Dec. 31, 2014 | (49,326) | $ 2 | 0 | (49,328) | ||
Balance at, (shares) at Dec. 31, 2014 | 1,954,488 | |||||
Increase (Decrease) in Redeemable Convertible Preferred Stock | ||||||
Remeasurement of fair value and settlement of Series A redeemable convertible preferred stock liability | 0 | |||||
Accretion of redeemable convertible preferred stock to redemption value | 4,180 | |||||
Conversion of Series A and B redeemable convertible preferred stock into common stock | $ (106,341) | |||||
Conversion of Series A and B redeemable convertible preferred stock into common stock (shares) | (69,113,168) | |||||
Balance at, at Dec. 31, 2015 | $ 0 | |||||
Balance at, (shares) at Dec. 31, 2015 | 0 | |||||
Increase (Decrease) in Stockholders' Deficit | ||||||
Accretion of redeemable convertible preferred stock to redemption value | $ (4,180) | (1,403) | (2,777) | |||
Conversion of Series A and B redeemable convertible preferred stock into common stock | 106,341 | $ 20 | 106,321 | |||
Conversion of Series A and B redeemable convertible preferred stock into common stock (shares) | 19,746,614 | |||||
Common stock issued | 126,230 | $ 7 | 126,223 | |||
Issuance of stock (shares) | 6,900,000 | |||||
Common stock issued for license | 4,492 | 4,492 | ||||
Common stock issued for license (shares) | 85,714 | |||||
Vesting of restricted stock purchase | 330 | 330 | ||||
Vesting of restricted stock purchase (shares) | 583,435 | |||||
Common stock issued on exercise of stock options | $ 45 | 45 | ||||
Common stock issued on exercise of stock options (shares) | 89,549 | 89,549 | ||||
Stock-based compensation expense | $ 3,223 | 3,223 | ||||
Net loss | (46,360) | (46,360) | ||||
Balance at, at Dec. 31, 2015 | $ 140,795 | $ 29 | $ 239,231 | $ (98,465) | ||
Balance at, (shares) at Dec. 31, 2015 | 29,359,800 |
Statements of Redeemable Conve6
Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2014 | Dec. 31, 2013 | |
Series A | ||
Stock issuance costs | $ 16 | $ 15 |
Series B | ||
Stock issuance costs | 146 | |
Series A Redeemable Convertible Preferred Stock Derivative Liability [Member] | ||
Derivative liability | $ 393 |
Statements of Cash Flows
Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
CASH FLOWS FROM OPERATING ACTIVITIES: | |||
Net loss | $ (46,360) | $ (20,807) | $ (18,116) |
Adjustments to reconcile net loss to net cash used in operating activities: | |||
Depreciation and amortization | 873 | 666 | 534 |
Loss on disposal of fixed assets | 33 | 0 | |
Remeasurement of Series A redeemable convertible preferred stock liability | 0 | 297 | 2,455 |
Stock-based compensation | 3,223 | 350 | 138 |
Fair value of stock issued for license | 4,492 | 0 | 0 |
Changes in operating assets and liabilities: | |||
Prepaid expenses | (87) | (753) | (73) |
Other assets, current | 22 | (323) | 149 |
Accounts payable | 2,705 | (304) | (465) |
Payable due to related party | (14) | (115) | (68) |
Accrued liabilities | 2,834 | 599 | 183 |
Accrued compensation | 1,395 | 271 | 494 |
Other liabilities, current | 19 | 17 | 38 |
Other liabilities, noncurrent | (25) | (19) | 31 |
Net cash used in operating activities | (30,890) | (20,121) | (14,700) |
CASH FLOWS FROM INVESTING ACTIVITIES: | |||
Purchase of property and equipment | (993) | (323) | (940) |
Increase in restricted cash | 0 | (60) | 0 |
Net cash used in investing activities | (993) | (383) | (940) |
CASH FLOWS FROM FINANCING ACTIVITIES: | |||
Proceeds from issuance of common stock, net of issuance costs | 126,230 | 0 | 0 |
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs | 0 | 68,838 | 15,235 |
Proceeds from sale of restricted stock | 2,108 | 408 | 43 |
Repurchase of unvested restricted stock purchases | (67) | 0 | 0 |
Proceeds from the exercise of common stock options | 45 | 49 | 1 |
Net cash provided by financing activities | 128,316 | 69,295 | 15,279 |
Net increase (decrease) in cash and cash equivalents | 96,433 | 48,791 | (361) |
Cash and cash equivalents at beginning of period | 52,069 | 3,278 | 3,639 |
Cash and cash equivalents at end of period | 148,502 | 52,069 | 3,278 |
SUPPLEMENTAL DISCLOSURES OF NON-CASH FINANCING INFORMATION: | |||
Remeasurement and settlement of fair value of Series A redeemable convertible preferred stock liability | 0 | 2,526 | 4,885 |
Accretion of Series A redeemable convertible preferred stock | $ 4,180 | $ 2,965 | $ 1,735 |
Organization and Basis of Prese
Organization and Basis of Presentation | 12 Months Ended |
Dec. 31, 2015 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Organization and Description of Business | Organization and Basis of Presentation Global Blood Therapeutics Inc. (the “Company”, “we”, “us”, and “our”) was incorporated in Delaware in February 2011 and commenced operations in May 2012. We are a clinical-stage biopharmaceutical company dedicated to discovering, developing and commercializing novel therapeutics to treat grievous blood-based disorders with significant unmet need. Our primary activities have been establishing our facilities, recruiting personnel, conducting development of our product candidates, including clinical trials, and raising capital. Our principal operations are based in South San Francisco, California, and we operate in one segment. Reverse Stock Split In July 2015 , our Board of Directors approved an amendment to our amended and restated certificate of incorporation to effect a reverse split of our issued and outstanding common stock at a 1 -for- 3.5 ratio, which was effected on July 30, 2015 . The par value and authorized shares of common stock and convertible preferred stock were not adjusted as a result of the reverse split. All issued and outstanding common stock, options to purchase common stock and per share amounts contained in the financial statements have been retroactively adjusted to reflect the reverse stock split for all periods presented. The financial statements have also been retroactively adjusted to reflect a proportional adjustment to the conversion ratio for each series of preferred stock that was effected in connection with the reverse stock split. Initial Public Offering On August 11, 2015 , our registration statement on Form S-1 (File No. 333-205563) relating to our initial public offering (“IPO”) of common stock became effective. The IPO closed on August 17, 2015 at which time we issued 6,900,000 shares of our common stock at a price of $20.00 per share. We received $126.2 million , net of underwriting discounts and commissions, and offering expenses incurred by us. Upon the closing of our IPO, all outstanding shares of our redeemable convertible preferred stock converted by their terms into 19,746,614 shares of common stock. See Note 6, “Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit).” Need for Additional Capital In the course of our development activities, we have sustained operating losses and we expect such losses to continue over the next several years. Our ultimate success depends on the outcome of our research and development activities. As of December 31, 2015 , we had an accumulated deficit of $98.5 million . We expect to incur additional losses in the future to conduct product research and development and we anticipate the need to raise additional capital to fully implement our business plan. We intend to raise such capital through the issuance of additional equity, and potentially through borrowings, and strategic alliances with partner companies. However, if such financing is not available at adequate levels or when it will be required, we will need to reevaluate our operating plans. We believe that our existing cash and cash equivalents will be sufficient to fund our cash requirements through mid-2017. |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 12 Months Ended |
Dec. 31, 2015 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | Summary of Significant Accounting Policies Basis of Presentation The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Use of Estimates The preparation of the accompanying financial statements in accordance with U.S. GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of costs and expenses during the reporting period. We base our estimates and assumptions on historical experience when available and on various factors that we believe to be reasonable under the circumstances. We evaluate our estimates and assumptions on an ongoing basis. Our actual results could differ from these estimates under different assumptions or conditions. Cash and Cash Equivalents We consider all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents. Cash equivalents, which consist primarily of amounts invested in money market accounts, are stated at fair value. Concentration of Credit Risk Financial instruments that potentially subject us to a concentration of credit risk consist of cash and cash equivalents. Our cash and cash equivalents are held by a financial institution in the United States. Amounts on deposit may at times exceed federally insured limits. We believe that the financial institution is financially sound, and accordingly, minimal credit risk exists with respect to the financial institution. Fair Value Measurement The carrying amounts of certain financial instruments, including cash equivalents, restricted cash, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities. Property and Equipment, Net Property and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is provided using the straight-line method over the estimated useful lives of the assets, three years for computer equipment and five years for laboratory equipment. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the improvements. Depreciation and amortization begins at the time the asset is placed in service. Maintenance and repairs are charged as expense in the statements of operations and comprehensive loss as incurred. Upon sale or retirement of assets, the cost and related accumulated depreciation and amortization are removed from the balance sheet and any resulting gain or loss is reflected in operations. Impairment of Long-Lived Assets We evaluate our long-lived assets, including property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying value of these assets may not be recoverable. Recoverability of these assets is measured by comparison of the carrying amount of each asset to the future undiscounted cash flows the asset is expected to generate over its remaining life. If the asset is considered to be impaired, the amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired asset. There have been no impairments of our long-lived assets for the periods presented. Restricted Cash Restricted cash consists of money market funds held by our financial institution as collateral for our letter of credit under our facility lease. Accruals of Research and Development Costs We record accruals for estimated costs of research, preclinical, nonclinical and clinical studies and manufacturing development. These costs are a significant component of our research and development expenses. A substantial portion of our ongoing research and development activities are conducted by third-party service providers, including contract research organizations. We accrue the costs incurred under our agreements with these third parties based on actual work completed in accordance with agreements established with these third parties. We determine the actual costs through discussions with internal personnel and external service providers as to the progress or stage of completion of the services and the agreed-upon fee to be paid for such services. We make significant judgments and estimates in determining the accrual balance in each reporting period. As actual costs become known, we adjust our accruals. We have not experienced any material deviations between accrued clinical trial expenses and actual clinical trial expenses. However, actual services performed, number of subjects enrolled, and the rate of subject enrollment may vary from our estimates, resulting in adjustments to clinical trial expense in future periods. Changes in these estimates that result in material changes to our accruals could materially affect our results of operations. Leases We enter into lease agreements for our office and laboratory facilities. These leases are classified as operating leases. Rent expense is recognized on a straight-line basis over the noncancelable term of the lease and, accordingly, we record the difference between cash rent payments and the recognition of rent expense as a deferred rent liability, which is included within other liabilities on the balance sheet. Incentives granted under our facilities leases, including allowances to fund leasehold improvements, are deferred and are recognized as adjustments to rental expense on a straight-line basis over the noncancelable term of the lease. Comprehensive Income (Loss) Comprehensive income (loss) is defined as a change in equity of a business enterprise during a period, resulting from transactions from non-owner sources. There have been no items qualifying as other comprehensive income (loss) and, therefore, for all periods presented, our comprehensive income (loss) was the same as our net loss. Research and Development Research and development costs are expensed as incurred and consist of salaries and benefits, stock-based compensation expense, lab supplies and facility costs, as well as fees paid to other nonemployees and entities that conduct certain research and development activities on our behalf. Amounts incurred in connection with license agreements are also included in research and development expense. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are capitalized and then expensed as the related goods are delivered or the services are performed. Stock-Based Compensation We measure and recognize stock-based compensation expense, including employee and non-employee equity awards, based on fair value at the grant date. We use the Black-Scholes-Merton option-pricing model to calculate fair value. Stock-based compensation expense recognized in the statements of operations and comprehensive loss is based on options ultimately expected to vest, taking into consideration estimated forfeitures. Stock-based compensation expense is revised in subsequent periods, if necessary, if actual forfeitures differ from these estimates. When estimating forfeitures, we consider historic voluntary termination behaviors as well as trends of actual option forfeitures. For options granted to nonemployees, we revalue the unearned portion of the stock-based compensation and at each reporting period end the resulting change in fair value is recognized in the statements of operations and comprehensive loss over the period the related services are rendered. Income Taxes We use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. We must then assess the likelihood that the resulting deferred tax assets will be realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. Due to our lack of earnings history, the net deferred tax assets have been fully offset by a valuation allowance. We recognize benefits of uncertain tax positions if it is more likely than not that such positions will be sustained upon examination based solely on their technical merits, as the largest amount of benefit that is more likely than not to be realized upon the ultimate settlement. Our policy is to recognize interest and penalties related to the underpayment of income taxes as a component of income tax expense or benefit. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits. Net Loss per Share Attributable to Common Stockholders Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding during the period, without consideration of common stock equivalents. The net loss attributable to common stockholders is calculated by adjusting our net loss for the accretion on the redeemable convertible preferred stock. Diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since the effects of potentially dilutive securities are antidilutive given our net loss. Recent Accounting Pronouncements In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. ASU 2014-15 requires management to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. In doing so, companies will have reduced diversity in the timing and content of footnote disclosures than under today’s guidance. ASU 2014-15 is effective for us in the first quarter of 2017 with early adoption permitted. We do not believe the impact of adopting ASU 2014-15 on our financial statements will be material. In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes, which amends existing guidance to require that deferred income tax liabilities and assets be classified as noncurrent in a classified balance sheet, and eliminates the prior guidance which required an entity to separate deferred tax liabilities and assets into a current amount and a noncurrent amount in a classified balance sheet. The standard is effective for us in fiscal year 2017. Early adoption is permitted. As permitted by ASU 2015-17, we early-adopted this standard and applied it retrospectively to all periods of the tax provision presented. As we have full valuation allowance against the deferred assets and liabilities, there is no impact to the financial statements. We have reflected the change resulting from this pronouncement in Note 10, Income Taxes. In February 2016, the FASB issued ASU No. 2016-02, Leases. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases. The standard is effective for interim and annual periods beginning after December 15, 2018, with early adoption permitted. We are currently in the process of evaluating the impact the adoption of this new standard will have on our financial position or results of operations. |
Fair Value Measurements
Fair Value Measurements | 12 Months Ended |
Dec. 31, 2015 | |
Fair Value Disclosures [Abstract] | |
Fair Value Measurements | Fair Value Measurements Fair value accounting is applied for all financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis (at least annually). Financial instruments include cash and cash equivalents, restricted cash, accounts payable and accrued liabilities that approximate fair value due to their relatively short maturities. Assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1 —Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2 —Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and Level 3 —Unobservable inputs that are significant to the measurement of the fair value of the assets or liabilities that are supported by little or no market data. The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis: December 31, 2015 (in thousands) Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 148,642 $ 148,642 $ — $ — Total financial assets $ 148,642 $ 148,642 $ — $ — December 31, 2014 (in thousands) Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 52,209 $ 52,209 $ — $ — Total financial assets $ 52,209 $ 52,209 $ — $ — Our financial instruments consist of Level 1 assets. Where quoted prices for identical assets are available in an active market, securities are classified as Level 1. Level 1 assets consist of highly liquid money market funds, which as of December 31, 2015 and 2014 includes $140,000 of funds that are collateral for our facility lease that are included within restricted cash. There were no unrealized gains and losses in our investments in these money market funds. The following table sets forth a summary of the changes in the fair value of our Level 3 financial instruments as follows: (in thousands) Series A Redeemable Convertible Preferred Stock Liability Balance at January 1, 2014 $ 1,836 Net increase in fair value upon revaluation 297 Recognition of fair value of liability due to new obligation for Series A financing in April 393 Settlement of tranche liability due to issue of Series A redeemable convertible preferred (2,526 ) Balance at December 31, 2014 $ — The Series A redeemable convertible preferred stock liability stemmed from the initial sale of Series A redeemable convertible preferred stock wherein we were obligated to sell additional shares in subsequent closings contingent upon the achievement of certain development milestones. The subsequent closings were deemed to be freestanding financial instruments that were outside our control. We estimated the fair value of this liability using Black-Scholes-Merton Option Pricing models that include the assumptions of probability of the financing occurring, stock price per share, expected term, and discount rate. The change in fair value was recognized as a gain or loss in the statements of operations and comprehensive loss, with final settlement of the liability in 2014 upon the issuance of the final tranche of convertible preferred stock. |
Balance Sheet Components
Balance Sheet Components | 12 Months Ended |
Dec. 31, 2015 | |
Balance Sheet Components [Abstract] | |
Balance Sheet Components | Balance Sheet Components Property and Equipment Property and equipment consist of the following: December 31, (in thousands) 2015 2014 Laboratory equipment $ 3,151 $ 2,611 Computer equipment 596 472 Leasehold improvements 340 245 Construction-in-progress 129 — Total property and equipment 4,216 3,328 Less: accumulated depreciation and amortization (2,102 ) (1,305 ) Property and equipment, net $ 2,114 $ 2,023 Depreciation and amortization expense was $0.9 million for the year ended December 31, 2015 , $0.7 million for the year ended December 31, 2014 and $0.5 million for the year ended December 31, 2013 . Accrued Liabilities Accrued liabilities consist of the following: December 31, (in thousands) 2015 2014 Accrued clinical and manufacturing expenses $ 4,025 $ 749 Accrued professional and consulting services 287 153 Other 88 46 Total accrued liabilities $ 4,400 $ 948 Other liabilities, noncurrent Other noncurrent liabilities consists of the following: December 31, (in thousands) 2015 2014 Restricted shares subject to repurchase, noncurrent $ 1,470 $ 273 Deferred rent, noncurrent 86 111 Total other liabilities, noncurrent $ 1,556 $ 384 |
Common Stock
Common Stock | 12 Months Ended |
Dec. 31, 2015 | |
Equity [Abstract] | |
Common Stock | Common Stock Common Stock Reserved for Issuance We have reserved sufficient shares of common stock for issuance upon the exercise of stock options and restricted shares subject to future vesting. Common stockholders are entitled to dividends if and when declared by the board of directors, subject to the prior rights of any preferred stockholders. As of December 31, 2015 , no common stock dividends had been declared by the board of directors. We have reserved shares of common stock, on an as-converted basis, for future issuance as follows: December 31, 2015 2014 Series A redeemable convertible preferred stock outstanding, as converted — 14,260,904 Series B redeemable convertible preferred stock outstanding, as converted — 5,485,710 Restricted shares subject to future vesting 1,097,288 1,121,979 Options issued and outstanding 2,058,787 954,567 Shares available for future grant under the 2015 Plan 1,014,485 651,816 Employee stock purchase plan 50,000 — Total 4,220,560 22,474,976 Common Stock Issued for License Agreement In September, 2015, we executed an agreement with the Regents of the University of California, or the Regents, for an exclusive license to those rights the Regents may own in certain patents and patent applications relating to GBT440 and GBT440 analogs, and in exchange have committed to pay a royalty of less than 1% on future net sales. In connection with this agreement we issued 85,714 shares of our common stock with an estimated fair value of $4.5 million , which was recorded in research and development expense in our statement of operations. Restricted Stock In May 2012, we issued 1,345,709 shares of restricted common stock to founders at $0.0035 per share of which 1,249,282 were subject to future vesting. Under the related stock purchase agreements, we have the right to repurchase the common stock which right lapses according to individual vesting schedules. In order to vest, the holders are required to provide continued service to us. Upon vesting, the appropriate amounts are transferred from liabilities to additional paid-in capital. If the holder of any unvested restricted common stock is terminated for any reason, we have the right to repurchase the unvested shares at the stockholder’s original purchase price. As such, the shares subject to future vesting are not deemed outstanding for accounting purposes until the shares vest. We have issued stock awards to employees under the 2012 Stock Option and Grant Plan. Under the related stock purchase agreements, we have the right to repurchase the common stock at the lower of fair value and the stockholders’ original purchase price which right lapses according to individual vesting schedules. In order to vest, the holders are required to provide continued service to us. Upon vesting, the appropriate amounts are transferred from liabilities to additional paid in capital. If the holder of any unvested restricted common stock is terminated for any reason, we have the right to repurchase the unvested shares at the stockholder’s original purchase price. As such, the shares subject to future vesting are not deemed outstanding for accounting purposes until the shares vest. Restricted shares subject to repurchase and related liability were as follows: December 31, (in thousands except share data) 2015 2014 Restricted shares subject to repurchase: Shares issued to founders 6,250 174,150 Shares issued pursuant to the 2012 Stock Option and Grant Plan 1,091,038 947,829 Total restricted shares subject to repurchase 1,097,288 1,121,979 Liability pertaining to restricted shares subject to repurchase Other liabilities, current $ 677 $ 163 Other liabilities, noncurrent 1,470 273 Total liabilities pertaining to shares subject to repurchase $ 2,147 $ 436 |
Redeemable Convertible Preferre
Redeemable Convertible Preferred Stock and Stockhoders' Equity (Deficit) | 12 Months Ended |
Dec. 31, 2015 | |
Temporary Equity [Abstract] | |
Redeemable Convertible Preferred Stock and Stockholders’ Equity (Deficit) | Redeemable Convertible Preferred Stock and Stockholders’ Equity (Deficit) Following the IPO in August 2015 , all of our outstanding shares of our redeemable convertible preferred stock were converted into 19,746,614 shares of common stock and the related carrying value was reclassified to common stock and additional paid-in capital. Accordingly, there were no shares of redeemable convertible preferred stock outstanding as of December 31, 2015 . As of December 31, 2014 redeemable convertible preferred stock consisted of the following: (in thousands, except share amounts) Shares Authorized Shares Issued and Outstanding Net Carrying Value Aggregate Liquidation Preference Series A 50,163,168 49,913,168 $ 54,273 $ 55,254 Series B 19,200,000 19,200,000 47,888 48,035 Total redeemable convertible preferred stock 69,363,168 69,113,168 $ 102,161 $ 103,289 Prior to the conversion of our convertible preferred stock upon our IPO, the significant provisions of each series of the redeemable convertible preferred stock were as follows: Liquidation Upon liquidation, dissolution, or winding up of the Company (whether voluntary or involuntary) or Deemed Liquidation Event (as defined below), before any distribution or payment was to be made to the holders of any Series A redeemable convertible preferred stock or common stock, the holders of Series B redeemable convertible preferred stock would have been entitled to be paid out of our assets legally available for distribution, an amount equal to the original issue price of the Series B redeemable convertible preferred stock plus any dividends accrued, but unpaid thereon, whether or not declared, together with any other dividends declared but unpaid thereon. The holders of Series A redeemable convertible preferred stock would have been entitled to receive, prior and in preference to any distribution of any of the Company's assets legally available for distribution to the holders of common stock, an amount equal to the respective original issue price of Series A of redeemable convertible preferred stock, plus any dividends accrued, but unpaid thereon, whether or not declared, together with any other dividends declared but unpaid thereon. The original issue price was $2.50 for the Series B and $1.00 for the Series A redeemable convertible preferred stock. Voting Each holder of shares of redeemable convertible preferred stock was entitled to the number of votes equal to the number of shares of common stock into which such shares of redeemable convertible preferred stock could have been converted and had voting rights and powers equal to the voting rights and powers of the common stock, and except as provided by law or by other provisions of the Certificate of Incorporation, voted together with the common stock as a single class on an as-converted basis on all matters as to which holders of common stock had the right to vote. The holders of Series A redeemable convertible preferred stock, voting separately as a single class, were entitled to elect three members of the Company’s Board of Directors. All remaining members of the Company’s Board of Directors were elected by the holders of the common stock and any other series or class of voting stock, including the Series A and B redeemable convertible preferred stock, exclusively and voting together as a single class. Conversion The holders of redeemable convertible preferred stock were subject to certain optional and mandatory conversion rights. (i) Optional Conversion Rights: Each share of redeemable convertible preferred stock were convertible, at the option of the holder, into such number of fully paid shares of common stock as was determined by dividing the Original Issue Price by the Conversion Price in effect at the time of conversion. (ii) Mandatory Conversion Rights: Upon either (a) for each of Series A and Series B redeemable convertible preferred stock the date and time, or the occurrence of an event, specified by vote or written consent of holders of at least a majority of the then outstanding shares of Series A redeemable convertible preferred stock or Series B redeemable convertible preferred stock or (b) the closing of the sale of shares of common stock to the public in a qualified initial public offering, all outstanding shares of redeemable convertible preferred stock were automatically to be converted into shares of common stock, at the then effective conversion rate. Dividends Series A and Series B redeemable convertible preferred stock accrued dividends at a rate per annum of $0.08 and $0.20 per share, respectively. Dividends were cumulative and accrued on a day-to-day basis. Dividends were payable only when and if declared by the Board of Directors. No dividends were declared as of December 31, 2014 or through the conversion date in 2015. Redemption The Series A redeemable convertible preferred stock was redeemable, at the election of majority of the holders of Series A redeemable convertible preferred stock, on or after the later to occur of the redemption in full of all outstanding shares of Series B redeemable convertible preferred stock and the seventh anniversary of the Series A preferred stock issue date (or May 2019), in three annual installments at the original issue price of $1.00 per share, plus any unpaid accruing dividends (whether or not declared). The Series B redeemable convertible preferred stock was redeemable at the election of majority of the holders of Series B redeemable convertible preferred stock, on or after the seventh anniversary of the Series B preferred stock issue date (or December 2021), in three annual installments at the original issue price of $2.50 per share, plus any unpaid accruing dividends (whether or not declared). As only the passage of time was required for Series A and Series B to become redeemable, the Company was accreting the carrying value of Series A and Series B to their redemption value over the period from the date of issuance to May 2019 and December 2021, respectively, (the earliest redemption dates). In the event of a change of control of the Company, proceeds would have been distributed in accordance with the liquidation preferences set forth in its Amended and Restated Certificate of Incorporation unless the holders of redeemable convertible preferred stock had converted their preferred shares into common shares. Therefore, redeemable convertible preferred stock was classified outside of stockholders’ equity (deficit) on the accompanying balance sheets, as Series A and Series B preferred could have been redeemed and as events triggering the liquidation preferences were not solely within the Company’s control. Accretion of redeemable convertible preferred stock was $4.2 million for the year ended December 31, 2015 , $3.0 million for the year ended December 31, 2014 and $1.7 million for the year ended December 31, 2013 . The accretion was recorded as an offset to the additional paid in capital until such balance was depleted and any remaining accretion was recorded to accumulated deficit. |
Series A Redeemable Convertible
Series A Redeemable Convertible Preferred Stock Liability | 12 Months Ended |
Dec. 31, 2015 | |
Temporary Equity Disclosure [Abstract] | |
Series A Redeemable Convertible Preferred Stock Liability | Series A Redeemable Convertible Preferred Stock Liability The Company recorded the redeemable convertible preferred stock liability incurred in connection with its Series A redeemable convertible preferred stock as a derivative financial instrument liability at the fair value on the date of issuance, and remeasured on each subsequent balance sheet date. The Series A preferred stock liability stems from the initial sale of Series A redeemable convertible preferred stock wherein the Company was obligated to sell additional shares in subsequent closings contingent upon the achievement of certain development milestones. The subsequent closings were deemed to be freestanding financial instruments that were outside the control of the Company. The changes in fair value were recognized as a gain or loss in the statements of operations and comprehensive loss and liability is remeasured at each reporting period and settlement of the related Series A tranche closings. The Company estimated the fair value of this liability using the Black Scholes option pricing model that include assumptions of probability of achievement of the development milestones or funding of the financing, stock price per share, expected term and risk-free interest rate. At December 31, 2015 and 2014 , there were no outstanding obligations related to the Series A redeemable convertible preferred stock liability as all obligations were settled in the Tranche 4 closing of the issuance of Series A redeemable convertible preferred stock in October 2014. For the years ended December 31, 2015 , 2014 and 2013 , the Company recorded a total charge of zero , $297,000 and $2.5 million , respectively, for the changes in the fair value of the Series A redeemable convertible preferred stock liability in the statement of operations and comprehensive loss. For the years ended December 31, 2015 , 2014 and 2013 , the Company recorded zero , $2.5 million and $1.8 million , respectively, as the settlement of the outstanding obligation/right of the Series A redeemable convertible preferred stock liability in redeemable convertible preferred stock. |
Stock-based Awards
Stock-based Awards | 12 Months Ended |
Dec. 31, 2015 | |
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |
Stock-based Awards | Stock-based awards 2015 Stock Option and Incentive Plan In July 2015, the Company adopted the 2015 Stock Option and Incentive Plan (the “2015 Plan”). Under the 2015 Plan, 1,430,000 shares of our common stock were initially reserved for the issuance of stock options, restricted stock, and other equity-based awards to employees, non-employee directors, and consultants under terms and provisions established by the Board of Directors and approved by our stockholders. Awards granted under the 2015 Plan expire no later than 10 years from the date of grant. For incentive stock options and non-statutory stock options, the option price shall not be less than 100% of the fair market value on the day of grant. If at the time we grant an option and the optionee directly or by attribution owns stock possessing more than 10% of the total combined voting power of all our classes of stock, the option price is required to be at least 110% of the fair market value on the day of grant. Options granted typically vest over a four -year period but may be granted with different vesting terms. As of December 31, 2015 , there were 1,014,485 shares available for us to grant under the 2015 Plan. 2012 Stock Option and Grant Plan In 2012, the Company adopted the 2012 Stock Option and Grant Plan (the “2012 Plan”) under which our Board of Directors was authorized to grant incentive stock options to employees, including officers and members of the Board of Directors who are also employees of ours, and non-statutory stock options (options that do not qualify as incentive options) and/or our restricted stock and other equity-based awards to employees, officers, directors, or consultants of ours. Previously we had initially reserved 2,785,713 shares of common stock for issuance under the 2012 Plan. On April 9, 2015 we increased the number of shares available under the 2012 Plan by 1,000,000 to a total of 3,785,713 shares. Awards granted under the 2012 Plan expire no later than 10 years from the date of grant. For incentive stock options and nonstatutory stock options, the option price shall not be less than 100% of the fair market value on the day of grant. If at the time we grant an option, the optionee directly or by attribution owns more than 10% of the total combined voting power of all our classes of stock, the option price is required to be at least 110% of the fair market value on the day of grant. Options granted typically vest over a 4 -year period but may be granted with different vesting terms. Upon adoption of the 2015 Plan, no new awards or grants are permitted under the 2012 Plan. Stock Option Activity The following table summarizes activity under the Company’s stock option plans, including the 2015 Plan and the 2012 Plan and related information: (in thousands, except share and per share amounts and term) Number of Options Weighted- Average Exercise Price Weighted- Average remaining contractual term (years) Aggregate Intrinsic Value Outstanding — December 31, 2014 954,567 0.38 9.0 Options granted 1,611,581 11.54 Options exercised (89,549 ) 0.50 Options canceled (417,812 ) 2.40 Outstanding — December 31, 2015 2,058,787 $ 8.71 9.0 $ 50,910 Vested and exercisable — December 31, 2015 382,057 $ 2.93 7.9 $ 11,266 Vested and expected to vest — December 31, 2015 1,934,062 $ 8.53 8.9 $ 48,095 The aggregate intrinsic values of options outstanding, vested and exercisable, and vested and expected to vest were calculated as the difference between the exercise price of the options and the fair value our common stock as of December 31, 2015 . The total intrinsic value of options exercised was $427,000 for the year ended December 31, 2015 , $35,000 for the year ended December 31, 2014 and zero for the year ended December 31, 2013 . The weighted-average estimated fair value of stock options granted was $8.56 for the year ended December 31, 2015 , $0.34 for the year ended December 31, 2014 and $0.31 for the year ended December 31, 2013 . Stock Options Granted to Employees with Service-based Vesting Valuation Assumptions The fair values of stock options granted to employees were calculated using the following assumptions: Year Ended December 31, 2015 2014 2013 Expected term (in years) 5.3-6.3 6.0-6.1 6.0-6.1 Volatility 73.8%-87.6% 80.7%-93.0% 79.8%-86.6% Risk-free interest rate 1.5%-1.8% 1.89%-2.10% 1.12%-1.31% Dividend yield — — — The fair value of the shares of common stock underlying stock options before our IPO was determined by our Board of Directors. Prior to our IPO in August 2015, because there was no public market for our common stock, the Board of Directors determined fair value of the common stock at the time of grant of the option by considering a number of objective and subjective factors including important developments in our operations, valuations performed by an independent third party, sales of convertible preferred stock, actual operating results and financial performance, the conditions in the biotechnology industry and the economy in general, the stock price performance and volatility of comparable public companies, and the lack of liquidity of our common stock, among other factors. In determining the fair value of the options granted, we used the Black-Scholes-Merton option-pricing model and assumptions discussed below. Each of these inputs is subjective and generally requires significant judgment to determine. Expected Term —Our expected term represents the period that the options granted are expected to be outstanding and is determined using the simplified method (based on the mid-point between the vesting date and the end of the contractual term). We had very limited historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for our stock option grants. Expected Volatility —Prior to the IPO in August 2015, we were privately held and did not have any trading history for our common stock; accordingly, the expected volatility was estimated based on the average volatility for comparable publicly traded biopharmaceutical companies over a period equal to the expected term of the stock option grants. When selecting comparable publicly traded biopharmaceutical companies on which we have based our expected stock price volatility, we selected companies with comparable characteristics to us, including enterprise value, risk profiles, position within the industry, and with historical share price information sufficient to meet the expected life of the stock-based awards. The historical volatility data was computed using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the stock-based awards. We will continue to apply this process until a sufficient amount of historical information regarding the volatility of our own stock price becomes available. Sufficient trading history does not yet exist for our common stock, therefore the estimate of expected volatility is based on the volatility of other companies with similar products under development, market, size and other factors. Risk-Free Interest Rate —The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of option. Expected Dividend —We have never paid dividends on our common stock and have no plans to pay dividends on our common stock. Therefore, we used an expected dividend yield of zero. Stock Options Granted to Non-employees with Service-Based Vesting Valuation Assumptions Stock-based compensation related to stock options granted to non-employees is recognized as the stock options are earned. The fair value of the stock options granted is calculated at each reporting date using the Black-Scholes option-pricing model with the following assumptions: Year Ended December 31, 2015 2014 2013 Expected term (in years) 4.0-9.9 5.0-9.9 5.0-9.4 Volatility 73.4%-91.2% 77.6%-82.3% 79.7%-88.1% Risk-free interest rate 0.8-2.7% 1.5%-2.7% 0.9%-2.6% Dividend yield — — — Performance-Contingent Stock Options Granted to Employees Valuation Assumptions On April 9, 2015 , our Board of Directors granted a total of 227,139 performance-contingent awards to members of our senior management team, with an exercise price of $3.40 per share, which the Board of Directors determined was the fair market value on the grant date. The awards have dual triggers of vesting based upon the successful achievement of four corporate operating milestones within specified timelines, as well as a requirement for continued employment. When a performance goal is deemed to be probable of achievement, time-based vesting and recognition of stock-based compensation expense commences. In the event any of the corporate operating milestones are not achieved by the specified timelines, such vesting tranche will terminate and no longer be exercisable with respect to that portion of the shares. As of December 31, 2015 , we determined that the achievement of the requisite performance conditions was not probable and, as a result, no compensation cost was recognized for the performance-contingent awards. The fair value of employee performance-contingent options was estimated at the date of grant using a Black-Scholes-Merton option-pricing model with the following assumptions: Year Ended 2015 Expected term (in years) 1.8-2.4 Volatility 77.2%-79.1% Risk-free interest rate 0.5%-0.8% Dividend yield — % Restricted Stock Purchases When Restricted Stock Purchases (“RSPs”) are granted, the individual purchases the shares at the grant date fair value of the underlying common stock. The purchase of the stock is subject to forfeiture prior to vesting at the lower of fair value and the original purchase price. The award is treated similarly to an early exercise of stock options for accounting purposes. A summary of our non-vested restricted stock for the year ended December 31, 2015 is as follows: Year Ended Outstanding — January 1, 1,121,979 Granted: Serviced-based vesting conditions 433,568 Performance-contingent awards 99,285 Market-condition awards 99,285 Vested (583,435 ) Repurchased by Company (73,394 ) Outstanding — December 31, 1,097,288 Service-based awards —RSPs granted during the years ended December 31, 2015 , 2014 and 2013 generally vest over four years, subject to the individual holder's continued service relationship with us. The estimated weighted-average grant date fair value of restricted stock issued was $2.20 per share for the year ended December 31, 2015 , $0.33 per share for the year ended December 31, 2014 and $0.23 per share for the year ended December 31, 2013 . The restricted common stock granted to an employee is valued using the Black-Scholes-Merton option-pricing model based on the common stock fair value at the time of the grant. For restricted common stock issued to consultants, we remeasure the fair value of the restricted shares as they vest at each reporting period using the Black-Scholes-Merton option-pricing model reflecting the remaining vesting period. Performance-contingent award —On April 9, 2015 , our Board of Directors granted a performance-contingent restricted stock purchase to our Chief Executive Officer shares of 99,285 restricted common stock with a purchase price of $3.40 per share, which the Board of Directors determined was the fair market value on the grant date. The estimated weighted-average grant-date fair value of the performance-contingent restricted stock purchase was $1.38 . This awards has dual triggers of vesting based upon the successful achievement of four corporate operating milestones within specified timelines, as well as a requirement for continued employment. When a performance goal is deemed to be probable of achievement, time-based vesting and recognition of stock-based compensation expense commences. In the event any of the corporate operating milestones are not achieved by the specified timelines, such vesting tranche will terminate and no longer be exercisable with respect to that portion of the shares. As of December 31, 2015 , we determined that the achievement of the requisite performance conditions was not probable and, as a result, no compensation cost was recognized for the performance-contingent awards. Market-condition award —On April 9, 2015 , our Board of Directors granted a market-condition award to our Chief Executive Officer of 99,285 shares of restricted common stock, with a purchase price of $3.40 per share, which the Board of Directors determined was the fair market value on the grant date. The market-condition award does not vest until our market capitalization (determined based on the number of shares of common stock outstanding multiplied by the closing market price for our common stock as reported on NASDAQ) exceeds at least $2.0 billion for 20 consecutive trading days on or before the date twenty-four ( 24 ) months after the closing of our IPO. The fair value of the market-condition award of $0.70 was determined on the grant date utilizing a lattice model that was prepared by a third party valuation firm with an expected term of 2.4 years . In August 2015, we began to recognize compensation costs for this award concurrent with the closing of our IPO. Employee Stock Purchase Plan In July 2015, we adopted the 2015 Employee Stock Purchase Plan (the “2015 ESPP”). Under the 2015 ESPP, 50,000 shares of our common stock were initially reserved for employee purchases of our common stock under terms and provisions established by the Board of Directors and approved by our stockholders. Under the 2015 ESPP our employees may purchase common stock through payroll deductions at a price equal to 85% of the lower of the fair market value of the stock at the beginning of the offering period or at the end of each applicable purchase period. The 2015 ESPP provides for offering periods of six months in duration. The purchase periods end on either January 31st or July 31st. Contributions under the 2015 ESPP are limited to a maximum of 15% of an employee's eligible compensation. The fair values of the rights granted under the 2015 ESPP were calculated using the following assumptions: Year Ended Expected term (in years) 0.5 Volatility 65.8 % Risk-free interest rate 0.2 % Dividend yield — % Stock-Based Compensation Expense Total stock-based compensation recognized by our research and development function and our general and administrative function was as follows: Year Ended December 31, (in thousands) 2015 2014 2013 Research and development $ 2,031 $ 248 $ 113 General and administrative 1,192 102 25 Total stock-based compensation expense $ 3,223 $ 350 $ 138 Total stock-based compensation recognized by employees and non-employees was as follows: Year Ended December 31, (in thousands) 2015 2014 2013 Employee $ 2,359 $ 333 $ 136 Non-employee 864 17 2 Total stock-based compensation expense $ 3,223 $ 350 $ 138 Unrecognized Stock-Based Compensation Expense and Weighted-Average Remaining Amortization Period As of December 31, 2015 the unrecognized stock-based compensation cost, net of expected forfeitures, and the estimated weighted-average amortization period, using the straight-line attribution method, was as follows: (in thousands, except amortization period) Unrecognized Compensation Cost Weighted-average remaining amortization period (years) Options $ 10,354 2.9 Restricted stock purchases 973 2.5 ESPP 34 .1 Total stock-based compensation expense $ 11,361 1.83 |
Defined Contribution Plan
Defined Contribution Plan | 12 Months Ended |
Dec. 31, 2015 | |
Compensation and Retirement Disclosure [Abstract] | |
Defined Contribution Plan | Defined Contribution Plan In 2013, we began to sponsor a 401(k) retirement plan, in which substantially all of our full-time employees are eligible to participate. Eligible participants may contribute a percentage of their annual compensation to this plan, subject to statutory limitations. Prior to 2015, we had not provided any contributions to the plan. We made contributions to the Plan for eligible participants, and recorded contribution expenses of $33,000 for the year ended December 31, 2015 , $19,000 for the year ended December 31, 2014 and $11,000 for the year ended December 31, 2013 . |
Income Taxes
Income Taxes | 12 Months Ended |
Dec. 31, 2015 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | Income Taxes No provision for income taxes was recorded for the years ended December 31, 2015 and 2014 . We have incurred net operating losses for all the periods presented. We have not reflected any benefit of such net operating loss carryforwards in the accompanying financial statements. We have established a full valuation against the related deferred tax assets due to the uncertainty surrounding the realization of such assets. The effective tax rate of the provision for income taxes differs from the federal statutory rate as follows: Year Ended December 31, 2015 2014 Federal statutory income tax rate 34.0 % 34.0 % Non-deductible changes in fair value (4.8 ) (0.6 ) Federal and state tax credits 1.4 2.4 Change in valuation allowance (30.6 ) (35.8 ) Provision for Taxes 0.0 % 0.0 % The components of the deferred tax assets and liabilities are as follows: December 31, (in thousands) 2015 2014 Deferred tax assets: Net operating loss carryforwards $ 32,561 $ 17,651 Tax credits 2,584 1,630 Accruals and reserves 696 374 Stock based compensation 464 122 Gross deferred tax assets 36,305 19,777 Valuation allowance (36,147 ) (19,495 ) Net deferred tax assets 158 282 Deferred tax liabilities: Property and equipment (158 ) (282 ) Net deferred tax $ — $ — In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes, related to balance sheet classification of deferred taxes. The ASU requires that deferred tax assets and liabilities be classified as noncurrent in the statement of financial position, thereby simplifying the current guidance that requires an entity to separate deferred assets and liabilities into current and noncurrent amounts. We have early-adopted the ASU as of December 31, 2015 on a prospective basis and our statement of financial position as of this date reflects the revised classification of current deferred tax assets and liabilities as noncurrent. Realization of the deferred tax assets is dependent upon future taxable income, if any, the amount and timing of which are uncertain. We have established a valuation allowance to offset deferred tax assets as of December 31, 2015 and 2014 due to the uncertainty of realizing future tax benefits from its net operating loss carryforwards and other deferred tax assets. The valuation allowance increased by approximately $16.7 million and $8.9 million during the year ended December 31, 2015 and 2014 , respectively. The increase in the valuation allowance is mainly related to the increase in net operating loss carryforwards incurred during the respective taxable years. At December 31, 2015 , we had net operating loss carryforwards for Federal income tax purposes of $82.1 million which are available to offset future taxable income, if any, through 2035 and net operating loss carryforwards for state income tax purposes of $80.0 million which are available to offset future taxable income, if any, through 2035 . The net deferred tax asset above does not include any amounts attributable to excess stock option deductions. As of December 31, 2015 , we had research and development tax credit carryforwards of approximately $2.3 million and $1.7 million available to reduce future taxable income, if any, for federal and state income tax purposes, respectively. If not utilized, the federal credit carryforwards will begin expiring in 2031, and the state credits carryforward indefinitely. In general, if we experience a greater than 50 percentage point aggregate change in ownership over a three-year period (a Section 382 ownership change), utilization of our pre-change NOL carryforwards are subject to an annual limitation under Section 382 of the Internal Revenue Code (California has similar laws). The annual limitation generally is determined by multiplying the value of our stock at the time of such ownership change (subject to certain adjustments) by the applicable long-term tax-exempt rate. Such limitations may result in expiration of a portion of the NOL carryforwards before utilization. We have not utilized any NOL carryovers through December 31, 2015 . In addition, our deferred tax assets are subject to full valuation allowance, and thus no benefit for deferred tax assets are recorded on our books. Our ability to use the remaining NOL carryforwards may be further limited if we experience a Section 382 ownership change as a result of future changes in our stock ownership. No liability related to uncertain tax positions is recorded on the financial statements. It is our policy to include penalties and interest expense related to income taxes as a component of other expense and interest expense, respectively, as necessary. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: December 31, (in thousands) 2015 2014 Balance at beginning of year $ 634 $ 352 Additions based on tax positions related to current year 371 282 Decreases for prior period tax positions $ — $ — Unrecognized tax benefit - December 31 $ 1,005 $ 634 We do not expect that our uncertain tax positions will materially change in the next twelve months. The reversal of the uncertain tax benefits will not impact our effective tax rate as we continue to maintain a full valuation allowance against our deferred tax assets. We file income tax returns in the United States and California. We are not currently under examination by income tax authorities in federal, state or other jurisdictions. All tax returns will remain open for examination by the federal and state authorities for three and four years, respectively, from the date of utilization of any net operating loss or credits. |
Commitments and Contingencies
Commitments and Contingencies | 12 Months Ended |
Dec. 31, 2015 | |
Commitments and Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | Commitments and Contingencies Facilities In 2012, we entered into a noncancelable operating lease for approximately 16,000 square feet of laboratory and office space in South San Francisco, California for an initial term of 66 months. We recognize minimum rent payments under the facility operating lease on a straight-line basis over the term of the lease. In October 2014, we assumed the noncancelable operating lease from a neighboring tenant for approximately 12,000 square feet of adjacent laboratory and office space on substantially the same economic terms as our primary facility operating lease. We anticipate that related lease payments will expire in April 2018. Future aggregate minimum lease payments under the noncancelable operating leases are as follows (in thousands): Year ending December 31, Amount 2016 $ 1,209 2017 1,115 2018 380 Total $ 2,704 Through February 2015, we were a party to a Space Sharing Agreement and a Shared Services Agreement with a biotechnology company that is also majority-owned by TRV. Under these agreements, specified expenses were shared equally between the two companies at cost and not subject to any markup or markdown. Under these agreements, we recorded reimbursements of $33,000 for the year ended December 31, 2015 , $234,000 for the year ended December 31, 2014 and $107,000 for the year ended December 31, 2013 . We have a receivable of $24,000 from these reimbursements which are included within other current assets on the balance sheets as of December 31, 2014 . Rent expense for the facility operating lease consisted of the following: Year Ended December 31, (in thousands) 2015 2014 2013 Minimum rental $ 971 $ 554 $ 554 Net reimbursement under Space Sharing Agreement (10 ) (54 ) (52 ) Facility rental expense, net $ 961 $ 500 $ 502 Indemnifications We indemnify each of our directors and officers for certain events or occurrences, subject to certain limits, while the director is or was serving at our request in such capacity, as permitted under Delaware law and in accordance with its certificate of incorporation and bylaws. The term of the indemnification period lasts as long as a director may be subject to any proceeding arising out of acts or omissions of such director in such capacity. The maximum amount of potential future indemnification is unlimited; however, we currently hold director liability insurance. This insurance allows the transfer of risk associated with our exposure and may enable us to recover a portion of any future amounts paid. We believe that the fair value of these indemnification obligations is minimal. Accordingly, we have not recognized any liabilities relating to these obligations for any period presented. Other Liabilities for loss contingencies arising from claims, assessments, litigation, fines, and penalties and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably estimated. Legal costs incurred in connection with loss contingencies are expensed as incurred. |
Net Loss per Share Attributable
Net Loss per Share Attributable to Common Stockholders | 12 Months Ended |
Dec. 31, 2015 | |
Earnings Per Share [Abstract] | |
Net Loss per Share Attributable to Common Stockholders | Net Loss per Share Attributable to Common Stockholders The following table sets forth the computation of the basic and diluted net loss per share attributable to common stockholders during the years ended December 31, 2015 , 2014 and 2013 : Year Ended December 31, (in thousands, except share and per share data) 2015 2014 2013 Numerator: Net loss $ (46,360 ) $ (20,807 ) $ (18,116 ) Accretion and dividends on redeemable convertible preferred stock (4,180 ) (2,965 ) (1,735 ) Net loss attributable to common stockholders $ (50,540 ) $ (23,772 ) $ (19,851 ) Denominator: Weighted average common shares outstanding 12,806,697 1,673,919 1,230,241 Net loss per share attributable to common stockholders, basic and diluted $ (3.95 ) $ (14.20 ) $ (16.14 ) Since the Company was in a loss position for all periods presented, basic net loss per share attributable to common stockholders is the same as diluted net loss per share for all periods as the inclusion of all potential common shares outstanding would have been anti-dilutive. Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows: December 31, 2015 2014 2013 Redeemable convertible preferred stock — 19,746,614 8,260,906 Options to purchase common stock 2,058,787 954,567 618,923 Restricted stock subject to future vesting 1,097,288 1,121,979 691,117 2015 ESPP 9,491 — — Total 3,165,566 21,823,160 9,570,946 |
Related Party Transactions
Related Party Transactions | 12 Months Ended |
Dec. 31, 2015 | |
Related Party Transactions [Abstract] | |
Related Party Transactions | Related Party Transactions Our majority investors are investment funds controlled by Third Rock Ventures, LLC (“TRV”) and two members of our Board of Directors are also partners in TRV. Management and advisory fee expense incurred with TRV was $65,000 for the year ended December 31, 2015 , $332,000 for the year ended December 31, 2014 , and $499,000 for the year ended December 31, 2013 for services which we requested from TRV. Our outstanding payable to TRV was zero as of December 31, 2015 and $14,000 as of December 31, 2014 . |
Selected Quarterly Financial In
Selected Quarterly Financial Information (Unaudited) | 12 Months Ended |
Dec. 31, 2015 | |
Quarterly Financial Information Disclosure [Abstract] | |
Selected Quarterly Financial Information (Unaudited) | Selected Quarterly Financial Information (unaudited) The following table provides the selected quarterly financial data for 2015 and 2014 : Quarter Ended (in thousands, except per share amounts) December 31, September 30, June 30, March 31, December 31, September 30, June 30, March 31,2014 Loss from operations $ (15,598 ) $ (14,775 ) $ (8,600 ) $ (7,420 ) $ (5,314 ) $ (5,200 ) $ (5,128 ) $ (4,869 ) Net loss $ (15,585 ) $ (14,764 ) $ (8,594 ) $ (7,417 ) $ (5,313 ) $ (5,222 ) $ (5,165 ) $ (5,107 ) Net loss attributable to common shareholders $ (15,585 ) $ (15,551 ) $ (10,747 ) $ (8,657 ) $ (6,214 ) $ (5,987 ) $ (5,876 ) $ (5,695 ) Net loss per share attributable to common shareholders - basic and diluted (1) $ (0.53 ) $ (0.90 ) $ (4.84 ) $ (4.22 ) $ (3.27 ) $ (3.53 ) $ (3.68 ) $ (3.81 ) (1) The full year net loss per share of common stock, basic and diluted, may not equal the sum of the quarters due to weighting of outstanding shares. |
Summary of Significant Accoun22
Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
Dec. 31, 2015 | |
Accounting Policies [Abstract] | |
Basis of Preparation and Use of Estimates | Basis of Presentation The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). |
Use of Estimates | Use of Estimates The preparation of the accompanying financial statements in accordance with U.S. GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of costs and expenses during the reporting period. We base our estimates and assumptions on historical experience when available and on various factors that we believe to be reasonable under the circumstances. We evaluate our estimates and assumptions on an ongoing basis. Our actual results could differ from these estimates under different assumptions or conditions. |
Cash and Cash Equivalents | Cash and Cash Equivalents We consider all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents. Cash equivalents, which consist primarily of amounts invested in money market accounts, are stated at fair value. |
Concentration of Credit Risk | Concentration of Credit Risk Financial instruments that potentially subject us to a concentration of credit risk consist of cash and cash equivalents. Our cash and cash equivalents are held by a financial institution in the United States. Amounts on deposit may at times exceed federally insured limits. We believe that the financial institution is financially sound, and accordingly, minimal credit risk exists with respect to the financial institution. |
Fair Value Measurement | Fair Value Measurement The carrying amounts of certain financial instruments, including cash equivalents, restricted cash, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities. |
Property and Equipment, Net | Property and Equipment, Net Property and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is provided using the straight-line method over the estimated useful lives of the assets, three years for computer equipment and five years for laboratory equipment. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the improvements. Depreciation and amortization begins at the time the asset is placed in service. Maintenance and repairs are charged as expense in the statements of operations and comprehensive loss as incurred. Upon sale or retirement of assets, the cost and related accumulated depreciation and amortization are removed from the balance sheet and any resulting gain or loss is reflected in operations. |
Impairment of Long-Lived Assets | Impairment of Long-Lived Assets We evaluate our long-lived assets, including property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying value of these assets may not be recoverable. Recoverability of these assets is measured by comparison of the carrying amount of each asset to the future undiscounted cash flows the asset is expected to generate over its remaining life. If the asset is considered to be impaired, the amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired asset. There have been no impairments of our long-lived assets for the periods presented. |
Restricted Cash | Restricted Cash Restricted cash consists of money market funds held by our financial institution as collateral for our letter of credit under our facility lease. |
Research and Development Costs | Accruals of Research and Development Costs We record accruals for estimated costs of research, preclinical, nonclinical and clinical studies and manufacturing development. These costs are a significant component of our research and development expenses. A substantial portion of our ongoing research and development activities are conducted by third-party service providers, including contract research organizations. We accrue the costs incurred under our agreements with these third parties based on actual work completed in accordance with agreements established with these third parties. We determine the actual costs through discussions with internal personnel and external service providers as to the progress or stage of completion of the services and the agreed-upon fee to be paid for such services. We make significant judgments and estimates in determining the accrual balance in each reporting period. As actual costs become known, we adjust our accruals. We have not experienced any material deviations between accrued clinical trial expenses and actual clinical trial expenses. However, actual services performed, number of subjects enrolled, and the rate of subject enrollment may vary from our estimates, resulting in adjustments to clinical trial expense in future periods. Changes in these estimates that result in material changes to our accruals could materially affect our results of operations. Research and Development Research and development costs are expensed as incurred and consist of salaries and benefits, stock-based compensation expense, lab supplies and facility costs, as well as fees paid to other nonemployees and entities that conduct certain research and development activities on our behalf. Amounts incurred in connection with license agreements are also included in research and development expense. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are capitalized and then expensed as the related goods are delivered or the services are performed. |
Leases | Leases We enter into lease agreements for our office and laboratory facilities. These leases are classified as operating leases. Rent expense is recognized on a straight-line basis over the noncancelable term of the lease and, accordingly, we record the difference between cash rent payments and the recognition of rent expense as a deferred rent liability, which is included within other liabilities on the balance sheet. Incentives granted under our facilities leases, including allowances to fund leasehold improvements, are deferred and are recognized as adjustments to rental expense on a straight-line basis over the noncancelable term of the lease. |
Comprehensive Income (Loss) | Comprehensive Income (Loss) Comprehensive income (loss) is defined as a change in equity of a business enterprise during a period, resulting from transactions from non-owner sources. There have been no items qualifying as other comprehensive income (loss) and, therefore, for all periods presented, our comprehensive income (loss) was the same as our net loss. |
Stock-based Compensation | Stock-Based Compensation We measure and recognize stock-based compensation expense, including employee and non-employee equity awards, based on fair value at the grant date. We use the Black-Scholes-Merton option-pricing model to calculate fair value. Stock-based compensation expense recognized in the statements of operations and comprehensive loss is based on options ultimately expected to vest, taking into consideration estimated forfeitures. Stock-based compensation expense is revised in subsequent periods, if necessary, if actual forfeitures differ from these estimates. When estimating forfeitures, we consider historic voluntary termination behaviors as well as trends of actual option forfeitures. For options granted to nonemployees, we revalue the unearned portion of the stock-based compensation and at each reporting period end the resulting change in fair value is recognized in the statements of operations and comprehensive loss over the period the related services are rendered. |
Income Taxes | Income Taxes We use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. We must then assess the likelihood that the resulting deferred tax assets will be realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. Due to our lack of earnings history, the net deferred tax assets have been fully offset by a valuation allowance. We recognize benefits of uncertain tax positions if it is more likely than not that such positions will be sustained upon examination based solely on their technical merits, as the largest amount of benefit that is more likely than not to be realized upon the ultimate settlement. Our policy is to recognize interest and penalties related to the underpayment of income taxes as a component of income tax expense or benefit. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits. |
Net Loss per Share Attributable to Common Stockholders | Net Loss per Share Attributable to Common Stockholders Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding during the period, without consideration of common stock equivalents. The net loss attributable to common stockholders is calculated by adjusting our net loss for the accretion on the redeemable convertible preferred stock. Diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since the effects of potentially dilutive securities are antidilutive given our net loss. |
Recent Accounting Pronouncements | Recent Accounting Pronouncements In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. ASU 2014-15 requires management to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. In doing so, companies will have reduced diversity in the timing and content of footnote disclosures than under today’s guidance. ASU 2014-15 is effective for us in the first quarter of 2017 with early adoption permitted. We do not believe the impact of adopting ASU 2014-15 on our financial statements will be material. In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes, which amends existing guidance to require that deferred income tax liabilities and assets be classified as noncurrent in a classified balance sheet, and eliminates the prior guidance which required an entity to separate deferred tax liabilities and assets into a current amount and a noncurrent amount in a classified balance sheet. The standard is effective for us in fiscal year 2017. Early adoption is permitted. As permitted by ASU 2015-17, we early-adopted this standard and applied it retrospectively to all periods of the tax provision presented. As we have full valuation allowance against the deferred assets and liabilities, there is no impact to the financial statements. We have reflected the change resulting from this pronouncement in Note 10, Income Taxes. In February 2016, the FASB issued ASU No. 2016-02, Leases. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases. The standard is effective for interim and annual periods beginning after December 15, 2018, with early adoption permitted. We are currently in the process of evaluating the impact the adoption of this new standard will have on our financial position or results of operations. |
Series A Redeemable Convertible Preferred Stock Liability | The Company recorded the redeemable convertible preferred stock liability incurred in connection with its Series A redeemable convertible preferred stock as a derivative financial instrument liability at the fair value on the date of issuance, and remeasured on each subsequent balance sheet date. The Series A preferred stock liability stems from the initial sale of Series A redeemable convertible preferred stock wherein the Company was obligated to sell additional shares in subsequent closings contingent upon the achievement of certain development milestones. The subsequent closings were deemed to be freestanding financial instruments that were outside the control of the Company. The changes in fair value were recognized as a gain or loss in the statements of operations and comprehensive loss and liability is remeasured at each reporting period and settlement of the related Series A tranche closings. The Company estimated the fair value of this liability using the Black Scholes option pricing model that include assumptions of probability of achievement of the development milestones or funding of the financing, stock price per share, expected term and risk-free interest rate. |
Fair Value Measurements (Tables
Fair Value Measurements (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Fair Value Disclosures [Abstract] | |
Fair Value, Assets Measured on Recurring Basis | The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis: December 31, 2015 (in thousands) Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 148,642 $ 148,642 $ — $ — Total financial assets $ 148,642 $ 148,642 $ — $ — December 31, 2014 (in thousands) Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 52,209 $ 52,209 $ — $ — Total financial assets $ 52,209 $ 52,209 $ — $ — |
Summary of Changes in the Fair Value of Level 3 Inputs | The following table sets forth a summary of the changes in the fair value of our Level 3 financial instruments as follows: (in thousands) Series A Redeemable Convertible Preferred Stock Liability Balance at January 1, 2014 $ 1,836 Net increase in fair value upon revaluation 297 Recognition of fair value of liability due to new obligation for Series A financing in April 393 Settlement of tranche liability due to issue of Series A redeemable convertible preferred (2,526 ) Balance at December 31, 2014 $ — |
Balance Sheet Components (Table
Balance Sheet Components (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Balance Sheet Components [Abstract] | |
Property and Equipment, Net | Property and equipment consist of the following: December 31, (in thousands) 2015 2014 Laboratory equipment $ 3,151 $ 2,611 Computer equipment 596 472 Leasehold improvements 340 245 Construction-in-progress 129 — Total property and equipment 4,216 3,328 Less: accumulated depreciation and amortization (2,102 ) (1,305 ) Property and equipment, net $ 2,114 $ 2,023 |
Accrued Expenses | Accrued liabilities consist of the following: December 31, (in thousands) 2015 2014 Accrued clinical and manufacturing expenses $ 4,025 $ 749 Accrued professional and consulting services 287 153 Other 88 46 Total accrued liabilities $ 4,400 $ 948 |
Other Liabilities, Noncurrent | Other noncurrent liabilities consists of the following: December 31, (in thousands) 2015 2014 Restricted shares subject to repurchase, noncurrent $ 1,470 $ 273 Deferred rent, noncurrent 86 111 Total other liabilities, noncurrent $ 1,556 $ 384 |
Common Stock (Tables)
Common Stock (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Equity [Abstract] | |
Schedule of common stock reserved for issuance | We have reserved shares of common stock, on an as-converted basis, for future issuance as follows: December 31, 2015 2014 Series A redeemable convertible preferred stock outstanding, as converted — 14,260,904 Series B redeemable convertible preferred stock outstanding, as converted — 5,485,710 Restricted shares subject to future vesting 1,097,288 1,121,979 Options issued and outstanding 2,058,787 954,567 Shares available for future grant under the 2015 Plan 1,014,485 651,816 Employee stock purchase plan 50,000 — Total 4,220,560 22,474,976 |
Restricted shares subject to repurchase and related liability | Restricted shares subject to repurchase and related liability were as follows: December 31, (in thousands except share data) 2015 2014 Restricted shares subject to repurchase: Shares issued to founders 6,250 174,150 Shares issued pursuant to the 2012 Stock Option and Grant Plan 1,091,038 947,829 Total restricted shares subject to repurchase 1,097,288 1,121,979 Liability pertaining to restricted shares subject to repurchase Other liabilities, current $ 677 $ 163 Other liabilities, noncurrent 1,470 273 Total liabilities pertaining to shares subject to repurchase $ 2,147 $ 436 |
Redeemable Convertible Prefer26
Redeemable Convertible Preferred Stock and Stockhoders' Equity (Deficit) (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Temporary Equity [Abstract] | |
Schedule of redeemable convertible preferred stock | As of December 31, 2014 redeemable convertible preferred stock consisted of the following: (in thousands, except share amounts) Shares Authorized Shares Issued and Outstanding Net Carrying Value Aggregate Liquidation Preference Series A 50,163,168 49,913,168 $ 54,273 $ 55,254 Series B 19,200,000 19,200,000 47,888 48,035 Total redeemable convertible preferred stock 69,363,168 69,113,168 $ 102,161 $ 103,289 |
Stock-based Awards (Tables)
Stock-based Awards (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |
Stock option activity | The following table summarizes activity under the Company’s stock option plans, including the 2015 Plan and the 2012 Plan and related information: (in thousands, except share and per share amounts and term) Number of Options Weighted- Average Exercise Price Weighted- Average remaining contractual term (years) Aggregate Intrinsic Value Outstanding — December 31, 2014 954,567 0.38 9.0 Options granted 1,611,581 11.54 Options exercised (89,549 ) 0.50 Options canceled (417,812 ) 2.40 Outstanding — December 31, 2015 2,058,787 $ 8.71 9.0 $ 50,910 Vested and exercisable — December 31, 2015 382,057 $ 2.93 7.9 $ 11,266 Vested and expected to vest — December 31, 2015 1,934,062 $ 8.53 8.9 $ 48,095 |
Fair value assumptions of stock option awards and performance-contingent awards | The fair values of stock options granted to employees were calculated using the following assumptions: Year Ended December 31, 2015 2014 2013 Expected term (in years) 5.3-6.3 6.0-6.1 6.0-6.1 Volatility 73.8%-87.6% 80.7%-93.0% 79.8%-86.6% Risk-free interest rate 1.5%-1.8% 1.89%-2.10% 1.12%-1.31% Dividend yield — — — The fair value of employee performance-contingent options was estimated at the date of grant using a Black-Scholes-Merton option-pricing model with the following assumptions: Year Ended 2015 Expected term (in years) 1.8-2.4 Volatility 77.2%-79.1% Risk-free interest rate 0.5%-0.8% Dividend yield — % |
Fair value assumptions for non-employee awards | Stock-based compensation related to stock options granted to non-employees is recognized as the stock options are earned. The fair value of the stock options granted is calculated at each reporting date using the Black-Scholes option-pricing model with the following assumptions: Year Ended December 31, 2015 2014 2013 Expected term (in years) 4.0-9.9 5.0-9.9 5.0-9.4 Volatility 73.4%-91.2% 77.6%-82.3% 79.7%-88.1% Risk-free interest rate 0.8-2.7% 1.5%-2.7% 0.9%-2.6% Dividend yield — — — |
Non-vested restricted stock activity | A summary of our non-vested restricted stock for the year ended December 31, 2015 is as follows: Year Ended Outstanding — January 1, 1,121,979 Granted: Serviced-based vesting conditions 433,568 Performance-contingent awards 99,285 Market-condition awards 99,285 Vested (583,435 ) Repurchased by Company (73,394 ) Outstanding — December 31, 1,097,288 |
Fair value assumptions for employee stock purchase plan | The fair values of the rights granted under the 2015 ESPP were calculated using the following assumptions: Year Ended Expected term (in years) 0.5 Volatility 65.8 % Risk-free interest rate 0.2 % Dividend yield — % |
Stock-based compensation expense recognized | Total stock-based compensation recognized by our research and development function and our general and administrative function was as follows: Year Ended December 31, (in thousands) 2015 2014 2013 Research and development $ 2,031 $ 248 $ 113 General and administrative 1,192 102 25 Total stock-based compensation expense $ 3,223 $ 350 $ 138 Total stock-based compensation recognized by employees and non-employees was as follows: Year Ended December 31, (in thousands) 2015 2014 2013 Employee $ 2,359 $ 333 $ 136 Non-employee 864 17 2 Total stock-based compensation expense $ 3,223 $ 350 $ 138 |
Unrecognized stock-based compensation cost | As of December 31, 2015 the unrecognized stock-based compensation cost, net of expected forfeitures, and the estimated weighted-average amortization period, using the straight-line attribution method, was as follows: (in thousands, except amortization period) Unrecognized Compensation Cost Weighted-average remaining amortization period (years) Options $ 10,354 2.9 Restricted stock purchases 973 2.5 ESPP 34 .1 Total stock-based compensation expense $ 11,361 1.83 |
Income Taxes (Tables)
Income Taxes (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Income Tax Disclosure [Abstract] | |
Effective Income Tax Rate Reconciliation | The effective tax rate of the provision for income taxes differs from the federal statutory rate as follows: Year Ended December 31, 2015 2014 Federal statutory income tax rate 34.0 % 34.0 % Non-deductible changes in fair value (4.8 ) (0.6 ) Federal and state tax credits 1.4 2.4 Change in valuation allowance (30.6 ) (35.8 ) Provision for Taxes 0.0 % 0.0 % |
Components of Deferred Tax Assets and Liabilities | The components of the deferred tax assets and liabilities are as follows: December 31, (in thousands) 2015 2014 Deferred tax assets: Net operating loss carryforwards $ 32,561 $ 17,651 Tax credits 2,584 1,630 Accruals and reserves 696 374 Stock based compensation 464 122 Gross deferred tax assets 36,305 19,777 Valuation allowance (36,147 ) (19,495 ) Net deferred tax assets 158 282 Deferred tax liabilities: Property and equipment (158 ) (282 ) Net deferred tax $ — $ — |
Reconciliation of Unrecognized Tax Benefits | A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: December 31, (in thousands) 2015 2014 Balance at beginning of year $ 634 $ 352 Additions based on tax positions related to current year 371 282 Decreases for prior period tax positions $ — $ — Unrecognized tax benefit - December 31 $ 1,005 $ 634 |
Commitments and Contingencies (
Commitments and Contingencies (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Commitments and Contingencies Disclosure [Abstract] | |
Future Aggregate Minimum Lease Payments | Future aggregate minimum lease payments under the noncancelable operating leases are as follows (in thousands): Year ending December 31, Amount 2016 $ 1,209 2017 1,115 2018 380 Total $ 2,704 |
Rent Expense | Rent expense for the facility operating lease consisted of the following: Year Ended December 31, (in thousands) 2015 2014 2013 Minimum rental $ 971 $ 554 $ 554 Net reimbursement under Space Sharing Agreement (10 ) (54 ) (52 ) Facility rental expense, net $ 961 $ 500 $ 502 |
Net Loss per Share Attributab30
Net Loss per Share Attributable to Common Stockholders (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Earnings Per Share [Abstract] | |
Computation of basic and diluted net loss per share | The following table sets forth the computation of the basic and diluted net loss per share attributable to common stockholders during the years ended December 31, 2015 , 2014 and 2013 : Year Ended December 31, (in thousands, except share and per share data) 2015 2014 2013 Numerator: Net loss $ (46,360 ) $ (20,807 ) $ (18,116 ) Accretion and dividends on redeemable convertible preferred stock (4,180 ) (2,965 ) (1,735 ) Net loss attributable to common stockholders $ (50,540 ) $ (23,772 ) $ (19,851 ) Denominator: Weighted average common shares outstanding 12,806,697 1,673,919 1,230,241 Net loss per share attributable to common stockholders, basic and diluted $ (3.95 ) $ (14.20 ) $ (16.14 ) |
Potentially dilutive securities that were not included in diluted per share calculations | Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows: December 31, 2015 2014 2013 Redeemable convertible preferred stock — 19,746,614 8,260,906 Options to purchase common stock 2,058,787 954,567 618,923 Restricted stock subject to future vesting 1,097,288 1,121,979 691,117 2015 ESPP 9,491 — — Total 3,165,566 21,823,160 9,570,946 |
Selected Quarterly Financial 31
Selected Quarterly Financial Information (Unaudited) (Tables) | 12 Months Ended |
Dec. 31, 2015 | |
Quarterly Financial Information Disclosure [Abstract] | |
Selected Quarterly Financial Information (Unaudited) | The following table provides the selected quarterly financial data for 2015 and 2014 : Quarter Ended (in thousands, except per share amounts) December 31, September 30, June 30, March 31, December 31, September 30, June 30, March 31,2014 Loss from operations $ (15,598 ) $ (14,775 ) $ (8,600 ) $ (7,420 ) $ (5,314 ) $ (5,200 ) $ (5,128 ) $ (4,869 ) Net loss $ (15,585 ) $ (14,764 ) $ (8,594 ) $ (7,417 ) $ (5,313 ) $ (5,222 ) $ (5,165 ) $ (5,107 ) Net loss attributable to common shareholders $ (15,585 ) $ (15,551 ) $ (10,747 ) $ (8,657 ) $ (6,214 ) $ (5,987 ) $ (5,876 ) $ (5,695 ) Net loss per share attributable to common shareholders - basic and diluted (1) $ (0.53 ) $ (0.90 ) $ (4.84 ) $ (4.22 ) $ (3.27 ) $ (3.53 ) $ (3.68 ) $ (3.81 ) (1) The full year net loss per share of common stock, basic and diluted, may not equal the sum of the quarters due to weighting of outstanding shares. |
Organization and Basis of Pre32
Organization and Basis of Presentation (Details) $ / shares in Units, $ in Thousands | Aug. 17, 2015USD ($)$ / sharesshares | Jul. 31, 2015 | Dec. 31, 2015USD ($)segment | Dec. 31, 2014USD ($) |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||||
Number of operating segments | segment | 1 | |||
Class of Stock [Line Items] | ||||
Accumulated deficit | $ | $ (98,465) | $ (49,328) | ||
Common Stock | ||||
Class of Stock [Line Items] | ||||
Reverse stock split ratio | 0.2857 | |||
Proceeds from IPO | $ | $ 126,200 | |||
Common Stock | Conversion of Redeemable Convertible Preferred Stock to Common Stock | ||||
Class of Stock [Line Items] | ||||
Shares converted upon completion of IPO (shares) | shares | 19,746,614 | |||
Common Stock | IPO | ||||
Class of Stock [Line Items] | ||||
Shares issued (in shares) | shares | 6,900,000 | |||
Share price (usd per share) | $ / shares | $ 20 |
Summary of Significant Accoun33
Summary of Significant Accounting Policies (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Property, Plant and Equipment [Line Items] | |||
Impairment of long-lived assets | $ 0 | $ 0 | $ 0 |
Computer equipment | |||
Property, Plant and Equipment [Line Items] | |||
Estimated useful life | 3 years | ||
Laboratory equipment | |||
Property, Plant and Equipment [Line Items] | |||
Estimated useful life | 5 years |
Fair Value Measurements (Detail
Fair Value Measurements (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Restricted cash | $ 140 | $ 140 |
Recurring | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Total financial assets | 148,642 | 52,209 |
Recurring | Level 1 | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Total financial assets | 148,642 | 52,209 |
Recurring | Money market funds | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Total financial assets | 148,642 | 52,209 |
Recurring | Money market funds | Level 1 | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Total financial assets | 148,642 | 52,209 |
Recurring | Money market funds | Level 1 | Restricted cash | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Restricted cash | $ 140 | $ 140 |
Fair Value Measurements - Chang
Fair Value Measurements - Changes in the Fair Value of Level 3 (Details) - Series A redeemable convertible preferred stock liability $ in Thousands | 12 Months Ended |
Dec. 31, 2014USD ($) | |
Series A Redeemable Convertible Preferred Stock Liability | |
Beginning balance | $ 1,836 |
Net increase in fair value upon revaluation | 297 |
Recognition of fair value of liability due to new obligation for Series A financing in April 2014 | 393 |
Settlement of tranche liability due to issue of Series A redeemable convertible preferred shares | (2,526) |
Ending balance | $ 0 |
Balance Sheet Components - Prop
Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Property, Plant and Equipment [Line Items] | |||
Total property and equipment | $ 4,216 | $ 3,328 | |
Less: accumulated depreciation and amortization | (2,102) | (1,305) | |
Property and equipment, net | 2,114 | 2,023 | |
Depreciation and amortization expense | 873 | 666 | $ 534 |
Laboratory equipment | |||
Property, Plant and Equipment [Line Items] | |||
Total property and equipment | 3,151 | 2,611 | |
Computer equipment | |||
Property, Plant and Equipment [Line Items] | |||
Total property and equipment | 596 | 472 | |
Leasehold improvements | |||
Property, Plant and Equipment [Line Items] | |||
Total property and equipment | 340 | 245 | |
Construction-in-progress | |||
Property, Plant and Equipment [Line Items] | |||
Total property and equipment | $ 129 | $ 0 |
Balance Sheet Components - Accr
Balance Sheet Components - Accrued Expenses and Other Liabilities, Noncurrent (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 |
Balance Sheet Components [Abstract] | ||
Accrued clinical and manufacturing expenses | $ 4,025 | $ 749 |
Accrued professional and consulting services | 287 | 153 |
Other | 88 | 46 |
Total accrued expenses | $ 4,400 | $ 948 |
Balance Sheet Components - Othe
Balance Sheet Components - Other Liabilities, Noncurrent (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 |
Balance Sheet Components [Abstract] | ||
Restricted shares subject to repurchase, noncurrent | $ 1,470 | $ 273 |
Deferred rent, noncurrent | 86 | 111 |
Total other liabilities, noncurrent | $ 1,556 | $ 384 |
Common Stock - Common Stock Res
Common Stock - Common Stock Reserved (Details) - shares | Dec. 31, 2015 | Dec. 31, 2014 |
Class of Stock [Line Items] | ||
Shares reserved for future issuance (shares) | 4,220,560 | 22,474,976 |
Restricted stock subject to future vesting | ||
Class of Stock [Line Items] | ||
Shares reserved for future issuance (shares) | 1,097,288 | 1,121,979 |
Stock Options | ||
Class of Stock [Line Items] | ||
Shares reserved for future issuance (shares) | 2,058,787 | 954,567 |
Shares available for future grant under the 2015 Plan | ||
Class of Stock [Line Items] | ||
Shares reserved for future issuance (shares) | 1,014,485 | 651,816 |
ESPP | ||
Class of Stock [Line Items] | ||
Shares reserved for future issuance (shares) | 50,000 | 0 |
Series A | ||
Class of Stock [Line Items] | ||
Shares reserved for future issuance (shares) | 0 | 14,260,904 |
Series B | ||
Class of Stock [Line Items] | ||
Shares reserved for future issuance (shares) | 0 | 5,485,710 |
Common Stock - License Agreemen
Common Stock - License Agreement (Details) $ in Thousands | 12 Months Ended |
Dec. 31, 2015USD ($)shares | |
Class of Stock [Line Items] | |
Royalty fee as a percentage of future sales, less than | 1.00% |
Value of shares issued in research agreement | $ | $ 4,492 |
Common Stock | |
Class of Stock [Line Items] | |
Number of shares issued in research agreement | shares | 85,714 |
Common Stock - Restricted Stock
Common Stock - Restricted Stock (Details) - Founders - Restricted Stock - $ / shares | 1 Months Ended | ||
May. 31, 2012 | Dec. 31, 2015 | Dec. 31, 2014 | |
Class of Stock [Line Items] | |||
Shares issued to founders | 1,345,709 | ||
Weighted-average grant date fair value of restricted shares (usd per share) | $ 0.0035 | ||
Shares issued that are still subject to vesting | 1,249,282 | 6,250 | 174,150 |
Common Stock - Restricted Share
Common Stock - Restricted Shares Subject to Repurchase (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 | May. 31, 2012 |
Class of Stock [Line Items] | |||
Total restricted shares subject to repurchase | 1,097,288 | 1,121,979 | |
Liability pertaining to restricted shares subject to repurchase | $ 2,147 | $ 436 | |
Other liabilities, current | |||
Class of Stock [Line Items] | |||
Liability pertaining to restricted shares subject to repurchase | 677 | 163 | |
Other liabilities, noncurrent | |||
Class of Stock [Line Items] | |||
Liability pertaining to restricted shares subject to repurchase | $ 1,470 | $ 273 | |
Restricted Stock | |||
Class of Stock [Line Items] | |||
Shares issued pursuant to the 2012 Stock Option and Grant Plan | 1,097,288 | 1,121,979 | |
2012 Stock Option and Grant Plan | Restricted Stock | |||
Class of Stock [Line Items] | |||
Shares issued pursuant to the 2012 Stock Option and Grant Plan | 1,091,038 | 947,829 | |
Founders | Restricted Stock | |||
Class of Stock [Line Items] | |||
Shares issued to founders | 6,250 | 174,150 | 1,249,282 |
Redeemable Convertible Prefer43
Redeemable Convertible Preferred Stock and Stockhoders' Equity (Deficit) - Additional (Details) $ / shares in Units, $ in Thousands | Aug. 17, 2015shares | Dec. 31, 2015USD ($)installmentboard_member$ / sharesshares | Dec. 31, 2014USD ($)shares | Dec. 31, 2013USD ($)shares | Dec. 31, 2012shares | May. 31, 2012$ / shares |
Temporary Equity [Line Items] | ||||||
Redeemable convertible preferred stock, shares outstanding (shares) | shares | 0 | 69,113,168 | 28,913,168 | 13,663,168 | ||
Accretion of redeemable convertible preferred stock to redemption value | $ | $ 4,180 | $ 2,965 | $ 1,735 | |||
Series A | ||||||
Temporary Equity [Line Items] | ||||||
Liquidation preference per share (usd per share) | $ 1 | |||||
Number of boards members elected by shareholders (in board member) | board_member | 3 | |||||
Redeemable convertible preferred stock, shares outstanding (shares) | shares | 49,913,168 | |||||
Preferred stock dividends, dividend rate per annum (usd per share) | $ 0.08 | |||||
Number of annual installments for redemption (in installment) | installment | 3 | |||||
Redemption price per share (usd per share) | $ 1 | |||||
Series B | ||||||
Temporary Equity [Line Items] | ||||||
Liquidation preference per share (usd per share) | $ 2.50 | |||||
Redeemable convertible preferred stock, shares outstanding (shares) | shares | 19,200,000 | |||||
Preferred stock dividends, dividend rate per annum (usd per share) | 0.20 | |||||
Redemption price per share (usd per share) | $ 2.50 | |||||
Common Stock | Conversion of Redeemable Convertible Preferred Stock to Common Stock | ||||||
Temporary Equity [Line Items] | ||||||
Shares converted upon completion of IPO (shares) | shares | 19,746,614 |
Redeemable Convertible Prefer44
Redeemable Convertible Preferred Stock and Stockhoders' Equity (Deficit) - Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 |
Temporary Equity [Line Items] | ||||
Shares authorized (shares) | 0 | 69,363,168 | ||
Shares issued (shares) | 0 | 69,113,168 | ||
Shares outstanding (shares) | 0 | 69,113,168 | 28,913,168 | 13,663,168 |
Net Carrying Value | $ 0 | $ 102,161 | $ 28,225 | $ 9,451 |
Aggregate Liquidation Preference | $ 0 | $ 103,289 | ||
Redeemable Convertible Preferred Stock | ||||
Temporary Equity [Line Items] | ||||
Shares authorized (shares) | 69,363,168 | |||
Shares issued (shares) | 69,113,168 | |||
Shares outstanding (shares) | 69,113,168 | |||
Net Carrying Value | $ 102,161 | |||
Aggregate Liquidation Preference | $ 103,289 | |||
Series A | ||||
Temporary Equity [Line Items] | ||||
Shares authorized (shares) | 50,163,168 | |||
Shares issued (shares) | 49,913,168 | |||
Shares outstanding (shares) | 49,913,168 | |||
Net Carrying Value | $ 54,273 | |||
Aggregate Liquidation Preference | $ 55,254 | |||
Series B | ||||
Temporary Equity [Line Items] | ||||
Shares authorized (shares) | 19,200,000 | |||
Shares issued (shares) | 19,200,000 | |||
Shares outstanding (shares) | 19,200,000 | |||
Net Carrying Value | $ 47,888 | |||
Aggregate Liquidation Preference | $ 48,035 |
Series A Redeemable Convertib45
Series A Redeemable Convertible Preferred Stock Liability (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Temporary Equity Disclosure [Abstract] | |||
Change in fair value of Series A redeemable convertible preferred stock liability | $ 0 | $ (297) | $ (2,455) |
Remeasurement of fair value and settlement of Series A redeemable convertible preferred stock liability | $ 0 | $ 2,526 | $ 1,804 |
Stock-based Awards - Plan Summa
Stock-based Awards - Plan Summary (Details) - USD ($) | Apr. 09, 2015 | Jul. 31, 2015 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 |
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Intrinsic value of exercises in period | $ 427,000 | $ 35,000 | $ 0 | |||
Estimated weighted-average grant-date fair value of common stock underlying options granted | $ 8.56 | $ 0.34 | $ 0.31 | |||
2015 Plan | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Options available for future grants | 1,014,485 | |||||
2015 Plan | Stock Options | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Shares authorized for issuance (shares) | 1,430,000 | |||||
Expiration period | 10 years | |||||
Exercise price as a percentage of the fair market value | 100.00% | |||||
Exercise price as a percentage of the fair market value for optionee holding more than 10% total combined voting power | 110.00% | |||||
Vesting period | 4 years | |||||
2012 Plan | Stock Options | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Shares authorized for issuance (shares) | 3,785,713 | 2,785,713 | ||||
Increase in shares authorized for issuance under plan (shares) | 1,000,000 | |||||
Expiration period | 10 years | |||||
Exercise price as a percentage of the fair market value | 100.00% | |||||
Exercise price as a percentage of the fair market value for optionee holding more than 10% total combined voting power | 110.00% | |||||
Vesting period | 4 years | |||||
2015 ESPP | ESPP | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Shares authorized for issuance (shares) | 50,000 | |||||
Exercise price as a percentage of the fair market value | 85.00% | |||||
Offering period | 6 months | |||||
Maximum contribution to plan as a percent of employee's eligible compensation | 15.00% |
Stock-based Awards - Stock Opti
Stock-based Awards - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended | |
Dec. 31, 2015 | Dec. 31, 2014 | |
Number of Options | ||
Beginning balance, outstanding (shares) | 954,567 | |
Options granted (shares) | 1,611,581 | |
Options exercised (shares) | (89,549) | |
Options canceled (shares) | (417,812) | |
Ending balance, outstanding (shares) | 2,058,787 | 954,567 |
Exercisable, number of options (shares) | 382,057 | |
Vested and expected to vest, number of options (shares) | 1,934,062 | |
Weighted- Average Exercise Price | ||
Beginning balance, outstanding (usd per share) | $ 0.38 | |
Options granted (usd per share) | 11.54 | |
Options exercised (usd per share) | 0.50 | |
Options canceled (usd per share) | 2.40 | |
Ending balance, outstanding (usd per share) | 8.71 | $ 0.38 |
Exercisable, weighted-average exercise price (usd per share) | 2.93 | |
Vested and expected to vest, weighted-average exercise price (usd per share) | $ 8.53 | |
Outstanding, weighted-average remaining contractual term | 9 years | 9 years |
Exercisable, weighted-average remaining contractual term | 7 years 10 months 24 days | |
Vested and expected to vest, weighted-average remaining contractual term | 8 years 10 months 24 days | |
Balance outstanding, aggregate intrinsic value | $ 50,910 | |
Exercisable, aggregate intrinsic value | 11,266 | |
Vested and expected to vest, aggregate intrinsic value | $ 48,095 |
Stock-based Awards - Valuation
Stock-based Awards - Valuation Assumptions for Stock Awards (Details) - Stock Options | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Share-based Compensation Arrangement by Share-based Payment Award | |||
Volatility, minimum | 73.80% | 80.70% | 79.80% |
Volatility, maximum | 87.60% | 93.00% | 86.60% |
Risk-free interest rate, minimum | 1.50% | 1.89% | 1.12% |
Risk-free interest rate, maximum | 1.80% | 2.10% | 1.31% |
Dividend yield | 0.00% | 0.00% | 0.00% |
Minimum | |||
Share-based Compensation Arrangement by Share-based Payment Award | |||
Expected term (in years) | 5 years 3 months 18 days | 6 years | 6 years |
Maximum | |||
Share-based Compensation Arrangement by Share-based Payment Award | |||
Expected term (in years) | 6 years 3 months 18 days | 6 years 1 month 6 days | 6 years 1 month 6 days |
Stock-based Awards - Stock Op49
Stock-based Awards - Stock Options Granted to Non-Employee (Details) | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Share-based Goods and Nonemployee Services Transaction [Line Items] | |||
Dividend yield | 0.00% | 0.00% | 0.00% |
Minimum | |||
Share-based Goods and Nonemployee Services Transaction [Line Items] | |||
Expected term (in years) | 4 years | 5 years | 5 years |
Volatility rate | 73.40% | 77.60% | 79.70% |
Risk-free interest rate | 0.80% | 1.50% | 0.90% |
Maximum | |||
Share-based Goods and Nonemployee Services Transaction [Line Items] | |||
Expected term (in years) | 9 years 10 months 24 days | 9 years 10 months 24 days | 9 years 4 months 24 days |
Volatility rate | 91.20% | 82.30% | 88.10% |
Risk-free interest rate | 2.70% | 2.70% | 2.60% |
Stock-based Awards - Restricted
Stock-based Awards - Restricted Stock Purchases (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Restricted Stock Awards | |||
Stock-based compensation expense | $ 3,223 | $ 350 | $ 138 |
Weighted-average remaining amortization period | 1 year 9 months 29 days | ||
Restricted Stock | |||
Restricted Stock Awards | |||
Beginning balance, outstanding (shares) | 1,121,979 | ||
Vested (shares) | (583,435) | ||
Repurchased by Company (shares) | (73,394) | ||
Ending balance, outstanding (shares) | 1,097,288 | 1,121,979 | |
Vesting period | 4 years | ||
Unrecognized compensation cost, restricted stock awards | $ 973 | ||
Weighted-average remaining amortization period | 2 years 6 months | ||
Serviced-based vesting conditions | |||
Restricted Stock Awards | |||
Granted (shares) | 433,568 | ||
Weighted-average grant date fair value of restricted shares (usd per share) | $ 2.20 | $ 0.33 | $ 0.23 |
Performance-contingent awards | |||
Restricted Stock Awards | |||
Granted (shares) | 99,285 | ||
Market-condition awards | |||
Restricted Stock Awards | |||
Granted (shares) | 99,285 |
Stock-based Awards - Performanc
Stock-based Awards - Performance-Contingent and Market-Condition Awards (Details) | Aug. 17, 2015 | Apr. 09, 2015USD ($)milestone$ / sharesshares | Sep. 30, 2015USD ($) | Dec. 31, 2015USD ($)$ / sharesshares | Dec. 31, 2014USD ($) | Dec. 31, 2013USD ($) |
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Options granted in period (shares) | shares | 1,611,581 | |||||
Exercise price of options granted (usd per share) | $ / shares | $ 11.54 | |||||
Compensation expense recognized | $ | $ 3,223,000 | $ 350,000 | $ 138,000 | |||
Performance Awards | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Restricted shares granted (in shares) | shares | 99,285 | |||||
Performance Awards | Senior Management | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Options granted in period (shares) | shares | 227,139 | |||||
Exercise price of options granted (usd per share) | $ / shares | $ 3.40 | |||||
Number of operating milestones for performance vesting (in milestone) | milestone | 4 | |||||
Compensation expense recognized | $ | $ 0 | |||||
Restricted shares granted (in shares) | shares | 99,285 | |||||
Weighted-average grant date fair value of restricted shares (usd per share) | $ / shares | $ 1.38 | |||||
Performance-Contingent Options | Senior Management | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Exercise price of options granted (usd per share) | $ / shares | 3.40 | |||||
Performance Contingent Restricted Stock | Senior Management | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Exercise price of restricted shares granted (usd per share) | $ / shares | $ 3.40 | |||||
Market-condition awards | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Restricted shares granted (in shares) | shares | 99,285 | |||||
Market-condition awards | Chief Executive Officer | ||||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||||
Restricted shares granted (in shares) | shares | 99,285 | |||||
Weighted-average grant date fair value of restricted shares (usd per share) | $ / shares | $ 0.70 | |||||
Minimum market capitalization | $ | $ 2,000,000,000 | |||||
Minimum consecutive trading days for market capitalization | 20 days | |||||
Expiration period from IPO | 24 months | |||||
Expected term (in years) | 2 years 5 months |
Stock-based Awards - Fair Value
Stock-based Awards - Fair Value Assumptions of Performance-Contingent Awards (Details) - Performance-Contingent Options | 12 Months Ended |
Dec. 31, 2015 | |
Fair Value Assumptions and Methodology | |
Volatility, minimum | 77.20% |
Volatility, maximum | 79.10% |
Risk-free interest rate, minimum | 0.50% |
Risk-free interest rate, maximum | 0.80% |
Dividend yield | 0.00% |
Minimum | |
Fair Value Assumptions and Methodology | |
Expected term (in years) | 1 year 9 months 18 days |
Maximum | |
Fair Value Assumptions and Methodology | |
Expected term (in years) | 2 years 4 months 24 days |
Stock-based Awards - Fair Val53
Stock-based Awards - Fair Value Assumptions of Employee Stock Purchase Plan (Details) - ESPP | 12 Months Ended |
Dec. 31, 2015 | |
Share-based Compensation Arrangement by Share-based Payment Award | |
Expected term (in years) | 6 months |
Volatility | 65.80% |
Risk-free interest rate | 0.20% |
Dividend yield | 0.00% |
Stock-based Awards - Stock-base
Stock-based Awards - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
Stock-based compensation expense | $ 3,223 | $ 350 | $ 138 |
Unrecognized compensation cost | $ 11,361 | ||
Weighted-average remaining amortization period | 1 year 9 months 29 days | ||
Employee | |||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
Stock-based compensation expense | $ 2,359 | 333 | 136 |
Non-employee | |||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
Stock-based compensation expense | 864 | 17 | 2 |
Research and development | |||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
Stock-based compensation expense | 2,031 | 248 | 113 |
General and administrative | |||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | |||
Stock-based compensation expense | $ 1,192 | $ 102 | $ 25 |
Stock-based Awards - Unrecogniz
Stock-based Awards - Unrecognized Stock-based Compensation Expense (Details) $ in Thousands | 12 Months Ended |
Dec. 31, 2015USD ($) | |
Share-based Compensation Arrangement by Share-based Payment Award | |
Total unrecognized compensation cost | $ 11,361 |
Weighted-average remaining amortization period | 1 year 9 months 29 days |
Stock Options | |
Share-based Compensation Arrangement by Share-based Payment Award | |
Unrecognized compensation cost, options | $ 10,354 |
Weighted-average remaining amortization period | 2 years 10 months 24 days |
Restricted Stock | |
Share-based Compensation Arrangement by Share-based Payment Award | |
Unrecognized compensation cost, restricted stock awards | $ 973 |
Weighted-average remaining amortization period | 2 years 6 months |
ESPP | |
Share-based Compensation Arrangement by Share-based Payment Award | |
Unrecognized compensation cost, restricted stock awards | $ 34 |
Weighted-average remaining amortization period | 1 month 6 days |
Defined Contribution Plan (Deta
Defined Contribution Plan (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Compensation and Retirement Disclosure [Abstract] | |||
Contribution expenses | $ 33 | $ 19 | $ 11 |
Income Taxes - Effective Income
Income Taxes - Effective Income Tax Rate Reconciliation (Details) | 12 Months Ended | |
Dec. 31, 2015 | Dec. 31, 2014 | |
Income Tax Disclosure [Abstract] | ||
Federal statutory income tax rate | 34.00% | 34.00% |
Non-deductible changes in fair value | (4.80%) | (0.60%) |
Federal and state tax credits | 1.40% | 2.40% |
Change in valuation allowance | (30.60%) | (35.80%) |
Provision for Taxes | 0.00% | 0.00% |
Income Taxes - Components of De
Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 |
Deferred tax assets: | ||
Net operating loss carryforwards | $ 32,561 | $ 17,651 |
Tax credits | 2,584 | 1,630 |
Accruals and reserves | 696 | 374 |
Stock based compensation | 464 | 122 |
Gross deferred tax assets | 36,305 | 19,777 |
Valuation allowance | (36,147) | (19,495) |
Net deferred tax assets | 158 | 282 |
Deferred tax liabilities: | ||
Property and equipment | (158) | (282) |
Net deferred tax | $ 0 | $ 0 |
Income Taxes - Operating Loss C
Income Taxes - Operating Loss Carryforward (Details) - USD ($) $ in Millions | 12 Months Ended | |
Dec. 31, 2015 | Dec. 31, 2014 | |
Income Tax Disclosure [Abstract] | ||
Increase in valuation allowance | $ 16.7 | $ 8.9 |
Federal | ||
Operating Loss Carryforwards [Line Items] | ||
Operating loss carryforwards | 82.1 | |
State | ||
Operating Loss Carryforwards [Line Items] | ||
Operating loss carryforwards | $ 80 |
Income Taxes - Tax Credit Carry
Income Taxes - Tax Credit Carryforward (Details) - Research and development tax credit $ in Millions | Dec. 31, 2015USD ($) |
Federal | |
Tax Credit Carryforward [Line Items] | |
Tax credit carryforwards | $ 2.3 |
State | |
Tax Credit Carryforward [Line Items] | |
Tax credit carryforwards | $ 1.7 |
Income Taxes - Reconciliation o
Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2015 | Dec. 31, 2014 | |
Reconciliation of Unrecognized Tax Benefits | ||
Balance at beginning of year | $ 634 | $ 352 |
Additions based on tax positions related to current year | 371 | 282 |
Decreases for prior period tax positions | 0 | 0 |
Unrecognized tax benefit - December 31 | $ 1,005 | $ 634 |
Related Party Transactions (Det
Related Party Transactions (Details) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2015USD ($)board_member | Dec. 31, 2014USD ($) | Dec. 31, 2013USD ($) | |
Related Party Transaction | |||
Related party expenses | $ 65 | $ 332 | $ 499 |
Third Rock Ventures | Board Members that are partners in TRV | |||
Related Party Transaction | |||
Number of board members | board_member | 2 | ||
Third Rock Ventures | Management and Advisory Services | |||
Related Party Transaction | |||
Related party expenses | $ 65 | 332 | $ 499 |
Outstanding payable | $ 0 | $ 14 |
Commitments and Contingencies63
Commitments and Contingencies (Details) ft² in Thousands, $ in Thousands | 1 Months Ended | 12 Months Ended | |||
Oct. 31, 2014ft² | Dec. 31, 2015USD ($)company | Dec. 31, 2014USD ($) | Dec. 31, 2013USD ($) | Dec. 31, 2012ft² | |
Commitments and Contingencies Disclosure [Abstract] | |||||
Facility size (in square feet) | ft² | 12 | 16 | |||
Initial term | 66 months | ||||
Future Aggregate Minimum Lease Payments Under Noncancelable Operating Leases | |||||
2,016 | $ 1,209 | ||||
2,017 | 1,115 | ||||
2,018 | 380 | ||||
Total minimum lease payments | $ 2,704 | ||||
Number of companies in Space Sharing Agreement (in company) | company | 2 | ||||
Reimbursements from Space Sharing Agreement | $ 33 | $ 234 | $ 107 | ||
Sublease rent receivable | 24 | ||||
Rent Expense | |||||
Minimum rental | 971 | 554 | 554 | ||
Net reimbursement under Space Sharing Agreement | (10) | (54) | (52) | ||
Facility rental expense, net | $ 961 | $ 500 | $ 502 |
Net Loss per Share Attributab64
Net Loss per Share Attributable to Common Stockholders - Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Numerator: | |||||||||||
Net loss | $ (15,585) | $ (14,764) | $ (8,594) | $ (7,417) | $ (5,313) | $ (5,222) | $ (5,165) | $ (5,107) | $ (46,360) | $ (20,807) | $ (18,116) |
Accretion and dividends on redeemable convertible preferred stock | (4,180) | (2,965) | (1,735) | ||||||||
Net loss attributable to common stockholders | $ (15,585) | $ (15,551) | $ (10,747) | $ (8,657) | $ (6,214) | $ (5,987) | $ (5,876) | $ (5,695) | $ (50,540) | $ (23,772) | $ (19,851) |
Denominator: | |||||||||||
Weighted average common shares outstanding (shares) | 12,806,697 | 1,673,919 | 1,230,241 | ||||||||
Net loss per share attributable to common stockholders, basic and diluted (usd per share) | $ (0.53) | $ (0.90) | $ (4.84) | $ (4.22) | $ (3.27) | $ (3.53) | $ (3.68) | $ (3.81) | $ (3.95) | $ (14.20) | $ (16.14) |
Net Loss per Share Attributab65
Net Loss per Share Attributable to Common Stockholders - Antidilutive Securities (Details) - shares | 12 Months Ended | ||
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Antidilutive Securities | |||
Antidilutive securities excluded from earnings per share | 3,165,566 | 21,823,160 | 9,570,946 |
Redeemable convertible preferred stock | |||
Antidilutive Securities | |||
Antidilutive securities excluded from earnings per share | 0 | 19,746,614 | 8,260,906 |
Options to purchase common stock | |||
Antidilutive Securities | |||
Antidilutive securities excluded from earnings per share | 2,058,787 | 954,567 | 618,923 |
Restricted stock subject to future vesting | |||
Antidilutive Securities | |||
Antidilutive securities excluded from earnings per share | 1,097,288 | 1,121,979 | 691,117 |
2015 ESPP | |||
Antidilutive Securities | |||
Antidilutive securities excluded from earnings per share | 9,491 | 0 | 0 |
Selected Quarterly Financial 66
Selected Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | |
Quarterly Financial Information Disclosure [Abstract] | |||||||||||
Operating Income (Loss) | $ (15,598) | $ (14,775) | $ (8,600) | $ (7,420) | $ (5,314) | $ (5,200) | $ (5,128) | $ (4,869) | $ (46,393) | $ (20,511) | $ (15,663) |
Net loss | (15,585) | (14,764) | (8,594) | (7,417) | (5,313) | (5,222) | (5,165) | (5,107) | (46,360) | (20,807) | (18,116) |
Net loss attributable to common stockholders | $ (15,585) | $ (15,551) | $ (10,747) | $ (8,657) | $ (6,214) | $ (5,987) | $ (5,876) | $ (5,695) | $ (50,540) | $ (23,772) | $ (19,851) |
Net loss per share attributable to common stockholders, basic and diluted (usd per share) | $ (0.53) | $ (0.90) | $ (4.84) | $ (4.22) | $ (3.27) | $ (3.53) | $ (3.68) | $ (3.81) | $ (3.95) | $ (14.20) | $ (16.14) |