Cover Page
Cover Page - USD ($) $ in Billions | 12 Months Ended | ||
Dec. 31, 2019 | Jan. 31, 2020 | Jun. 30, 2019 | |
Cover page. | |||
Document Type | 10-K | ||
Document Annual Report | true | ||
Document Period End Date | Dec. 31, 2019 | ||
Document Transition Report | false | ||
Entity File Number | 001-36065 | ||
Entity Registrant Name | ACCELERON PHARMA INC. | ||
Entity Incorporation, State or Country Code | DE | ||
Entity Tax Identification Number | 27-0072226 | ||
Entity Address, Address Line One | 128 Sidney Street | ||
Entity Address, City or Town | Cambridge, | ||
Entity Address, State or Province | MA | ||
Entity Address, Postal Zip Code | 02139 | ||
City Area Code | 617 | ||
Local Phone Number | 649-9200 | ||
Title of 12(b) Security | Common Stock, $0.001 par value | ||
Security Exchange Name | NASDAQ | ||
Entity Well-known Seasoned Issuer | Yes | ||
Entity Voluntary Filers | No | ||
Entity Current Reporting Status | Yes | ||
Entity Interactive Data Current | Yes | ||
Entity Filer Category | Large Accelerated Filer | ||
Entity Small Business | false | ||
Entity Emerging Growth Company | false | ||
Entity Shell Company | false | ||
Entity Public Float | $ 1.8 | ||
Entity Common Stock, Shares Outstanding | 53,337,296 | ||
Entity Central Index Key | 0001280600 | ||
Amendment Flag | false | ||
Current Fiscal Year End Date | --12-31 | ||
Document Fiscal Year Focus | 2019 | ||
Document Fiscal Period Focus | FY | ||
Trading Symbol | XLRN |
Consolidated Balance Sheets
Consolidated Balance Sheets - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Current assets: | ||
Cash and cash equivalents | $ 237,677 | $ 144,052 |
Short-term investments | 193,692 | 147,260 |
Collaboration receivables (all amounts are with a related party) | 8,547 | 7,039 |
Prepaid expenses and other current assets | 10,000 | 7,662 |
Total current assets | 449,916 | 306,013 |
Property and equipment, net | 6,812 | 7,106 |
Operating lease - right of use asset, net | 23,908 | |
Long-term investments | 22,477 | 0 |
Other assets | 1,793 | 1,702 |
Total assets | 504,906 | 314,821 |
Current liabilities: | ||
Accounts payable | 2,295 | 419 |
Accrued expenses | 24,895 | 18,209 |
Deferred rent | 284 | |
Operating lease liability - right of use | 6,183 | |
Total current liabilities | 33,373 | 18,912 |
Deferred rent, net of current portion | 2,381 | |
Warrants to purchase common stock | 1,856 | 1,491 |
Operating lease liability - right of use, net of current portion | 20,201 | |
Total liabilities | 55,430 | 22,784 |
Commitments and contingencies (Note 8) | 0 | 0 |
Stockholders' equity: | ||
Undesignated preferred stock, $0.001 par value: 25,000,000 shares authorized and no shares issued or outstanding | 0 | 0 |
Common stock, $0.001 par value: 175,000,000 shares authorized; 53,123,567 and 46,260,747 shares issued and outstanding at December 31, 2019 and 2018, respectively | 53 | 47 |
Additional paid-in capital | 1,160,807 | 879,099 |
Accumulated deficit | (711,407) | (586,549) |
Accumulated other comprehensive income (loss) | 23 | (560) |
Total stockholders' equity | 449,476 | 292,037 |
Total liabilities and stockholders' equity | $ 504,906 | $ 314,821 |
Consolidated Balance Sheets (Pa
Consolidated Balance Sheets (Parenthetical) - $ / shares | Dec. 31, 2019 | Dec. 31, 2018 |
Stockholders' equity: | ||
Preferred stock, par value (in dollars per share) | $ 0.001 | $ 0.001 |
Undesignated preferred stock shares authorized (in shares) | 25,000,000 | 25,000,000 |
Preferred stock, shares issued (in shares) | 0 | 0 |
Preferred stock, shares outstanding (in shares) | 0 | 0 |
Common stock, par value (in dollars per share) | $ 0.001 | $ 0.001 |
Common stock, shares authorized (in shares) | 175,000,000 | 175,000,000 |
Common stock, shares issued (in shares) | 53,123,567 | 46,260,747 |
Common stock, shares outstanding (in shares) | 53,123,567 | 46,260,747 |
Consolidated Statements of Oper
Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Collaboration revenue: | |||
Revenue | $ 73,993 | $ 13,991 | $ 13,481 |
Costs and expenses: | |||
Research and development | 153,953 | 103,902 | 89,726 |
Selling, general and administrative | 56,485 | 34,503 | 33,738 |
Total costs and expenses | 210,438 | 138,405 | 123,464 |
Loss from operations | (136,445) | (124,414) | (109,983) |
Other income (expense), net | 819 | (52) | (992) |
Interest income | 10,706 | 5,568 | 2,553 |
Other income, net | 11,525 | 5,516 | 1,561 |
Loss before income taxes | (124,920) | (118,898) | (108,422) |
Income tax benefit (provision) | 62 | 27 | (32) |
Net loss | (124,858) | (118,871) | (108,454) |
Other comprehensive income (loss): | |||
Net unrealized holding gains (losses) on short- and long-term investments during the period, net of tax | 583 | 335 | (470) |
Comprehensive loss | $ (124,275) | $ (118,536) | $ (108,924) |
Net loss per share- basic and diluted (in dollars per share) | $ (2.38) | $ (2.59) | $ (2.68) |
Weighted-average number of common shares used in computing net loss per share-basic and diluted (in shares) | 52,453 | 45,898 | 40,420 |
License and milestone | |||
Collaboration revenue: | |||
Revenue | $ 60,000 | $ 0 | $ 541 |
Cost Sharing | |||
Collaboration revenue: | |||
Revenue | $ 13,993 | $ 13,991 | $ 12,940 |
Consolidated Statements of Stoc
Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands | Total | Common Stock | Additional Paid-In Capital | Accumulated Deficit | Comprehensive (Loss) Income |
Stockholders' equity beginning balance (in shares) at Dec. 31, 2016 | 38,251,826 | ||||
Stockholders' equity beginning balance at Dec. 31, 2016 | $ 225,597 | $ 39 | $ 590,474 | $ (364,491) | $ (425) |
AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||
Stock-based compensation | 28,248 | 28,248 | |||
Issuance of common stock (in shares) | 6,216,216 | ||||
Issuance of common stock | 215,802 | $ 6 | 215,796 | ||
Exercise of stock options (in shares) | 474,056 | ||||
Exercise of stock options | 3,893 | $ 1 | 3,892 | ||
Vesting of restricted stock units, net of shares withheld for taxes (in shares) | 282,158 | ||||
Vesting of restricted stock units, net of shares withheld for taxes | (226) | (226) | |||
Issuance of common stock related to ESPP (in shares) | 33,698 | ||||
Issuance of common stock related to ESPP | 827 | 827 | |||
Net exercise of warrants to purchase common stock (in shares) | 3,221 | ||||
Net exercise of warrants to purchase common stock | 0 | ||||
Unrealized gain/loss on available-for-sale securities, net of tax | (470) | (470) | |||
Net loss | (108,454) | (108,454) | |||
Stockholders' equity ending balance (in shares) at Dec. 31, 2017 | 45,261,175 | ||||
Stockholders' equity ending balance at Dec. 31, 2017 | 365,217 | $ 46 | 839,090 | (473,024) | (895) |
AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||
Stock-based compensation | 24,569 | 24,569 | |||
Exercise of stock options (in shares) | 779,711 | ||||
Exercise of stock options | 15,931 | $ 1 | 15,930 | ||
Vesting of restricted stock units, net of shares withheld for taxes (in shares) | 170,516 | ||||
Vesting of restricted stock units, net of shares withheld for taxes | (731) | (731) | |||
Issuance of common stock related to ESPP (in shares) | 30,896 | ||||
Issuance of common stock related to ESPP | 1,085 | 1,085 | |||
Net exercise of warrants to purchase common stock (in shares) | 18,449 | ||||
Net exercise of warrants to purchase common stock | 797 | 797 | |||
Unrealized gain/loss on available-for-sale securities, net of tax | 335 | 335 | |||
Net loss | (118,871) | (118,871) | |||
Stockholders' equity ending balance (in shares) at Dec. 31, 2018 | 46,260,747 | ||||
Stockholders' equity ending balance at Dec. 31, 2018 | 292,037 | $ 47 | 879,099 | (586,549) | (560) |
AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||
Stock-based compensation | 22,995 | 22,995 | |||
Issuance of common stock (in shares) | 6,151,163 | ||||
Issuance of common stock | $ 248,130 | $ 6 | 248,124 | ||
Exercise of stock options (in shares) | 344,000 | 344,257 | |||
Exercise of stock options | $ 10,096 | 10,096 | |||
Vesting of restricted stock units, net of shares withheld for taxes (in shares) | 334,141 | ||||
Vesting of restricted stock units, net of shares withheld for taxes | (802) | (802) | |||
Issuance of common stock related to ESPP (in shares) | 33,259 | ||||
Issuance of common stock related to ESPP | 1,295 | 1,295 | |||
Unrealized gain/loss on available-for-sale securities, net of tax | 583 | 583 | |||
Net loss | (124,858) | (124,858) | |||
Stockholders' equity ending balance (in shares) at Dec. 31, 2019 | 53,123,567 | ||||
Stockholders' equity ending balance at Dec. 31, 2019 | $ 449,476 | $ 53 | $ 1,160,807 | $ (711,407) | $ 23 |
Consolidated Statements of St_2
Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2019 | Dec. 31, 2017 | |
Statement of Stockholders' Equity [Abstract] | ||
Issuance costs | $ 500 | $ 397 |
Consolidated Statements of Cash
Consolidated Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Operating Activities | |||
Net loss | $ (124,858) | $ (118,871) | $ (108,454) |
Adjustments to reconcile net loss to net cash used in operating activities: | |||
Depreciation and amortization | 3,941 | 3,747 | 2,825 |
Stock-based compensation | 22,995 | 24,569 | 28,248 |
Other non-cash items | 128 | 409 | 1,168 |
Changes in assets and liabilities: | |||
Prepaid expenses and other current assets | (2,429) | (2,986) | (675) |
Collaboration receivables | (1,508) | (3,470) | (336) |
Non-cash lease expense | 5,143 | 0 | 0 |
Accounts payable | 1,876 | (673) | (504) |
Accrued expenses | 6,258 | 1,904 | 1,493 |
Operating lease obligations (Note 14) | (5,333) | ||
Other changes in operating assets and liabilities | (17) | 665 | (309) |
Net cash used in operating activities | (93,804) | (94,706) | (76,544) |
Investing Activities | |||
Purchase of investments | (395,138) | (73,570) | (179,935) |
Proceeds from sale of securities | 327,134 | 199,087 | 119,965 |
Purchases of property and equipment | (3,287) | (2,590) | (4,396) |
Net cash (used in) provided by investing activities | (71,291) | 122,927 | (64,366) |
Financing Activities | |||
Proceeds from issuance of common stock from follow-on public offering, net of issuance costs | 248,130 | 0 | 215,802 |
Payments for capital lease expenditures | 0 | (139) | 0 |
Net proceeds from exercises and vesting of stock awards, ESPP contributions, and exercise of warrants to purchase common stock | 10,590 | 16,285 | 4,494 |
Net cash provided by financing activities | 258,720 | 16,146 | 220,296 |
Net increase in cash, cash equivalents and restricted cash | 93,625 | 44,367 | 79,386 |
Cash, cash equivalents and restricted cash at beginning of period | 145,649 | 101,282 | 21,896 |
Cash, cash equivalents and restricted cash at end of period | 239,274 | 145,649 | 101,282 |
Supplemental Disclosure of Non-Cash Investing and Financing Activities: | |||
Cashless exercise of warrants | 0 | 797 | 0 |
Capitalized follow-on public offering costs included in accrued expenses | 0 | 221 | 0 |
Purchase of property and equipment included in accounts payable and accrued expenses | $ 444 | $ 1,159 | $ 194 |
Nature of Business
Nature of Business | 12 Months Ended |
Dec. 31, 2019 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Nature of Business | Nature of Business Acceleron Pharma Inc. (Acceleron or the Company) is a Cambridge, Massachusetts-based biopharmaceutical company dedicated to the discovery, development and commercialization of therapeutics to treat serious and rare diseases. The Company's leadership in the understanding of TGF-beta biology and protein engineering generates innovative compounds that engage the body's ability to regulate cellular growth and repair. The Company is subject to risks common to companies in the biotechnology industry, including, but not limited to, the risk that the Company never achieves profitability, the need for substantial additional financing, risk of relying on third parties, risks of clinical trial failures, dependence on key personnel, protection of proprietary technology and compliance with government regulations. |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 12 Months Ended |
Dec. 31, 2019 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | Summary of Significant Accounting Policies The accompanying consolidated financial statements reflect the application of certain significant accounting policies as described below and elsewhere in these notes to the consolidated financial statements. The Company believes that a significant accounting policy is one that is both important to the portrayal of the Company's financial condition and results, and requires management's most difficult, subjective, or complex judgments, often as the result of the need to make estimates about the effect of matters that are inherently uncertain. Principles of Consolidation The accompanying consolidated financial statements include those of the Company and its wholly-owned subsidiary, Acceleron Securities Corp. All significant intercompany balances and transactions have been eliminated in consolidation. Basis of Presentation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB). Use of Estimates The preparation of financial statements in conformity with GAAP requires management 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 expensed during the reporting period. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these consolidated financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes and management must select an amount that falls within that range of reasonable estimates. This process may result in actual results differing materially from those estimated amounts used in the preparation of the consolidated financial statements if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. In preparing these consolidated financial statements, management used estimates in the following areas, among others: accrued and prepaid clinical expenses, stock-based compensation expense, revenue recognition and the recoverability of the Company's net deferred tax assets and related valuation allowance. Collaboration Receivable Credit is extended to customers based upon an evaluation of the customer's financial condition. Collaboration receivables are recorded at net realizable value. The Company does not charge interest on past due balances. Collaboration receivables are determined to be past due when the payment due date is exceeded. The Company utilizes a specific identification accounts receivable reserve methodology based on a review of outstanding balances and previous activities to determine the allowance for doubtful accounts. The Company charges off uncollectible receivables at the time the Company determines the receivable is no longer collectible. The Company did no t have an allowance for doubtful accounts at December 31, 2019 or 2018 . Segment Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision making group, in making decisions on how to allocate resources and assess performance. The Company's chief operating decision maker is the chief executive officer. The Company and the chief executive officer view the Company's operations and manage its business as one operating segment, which is the discovery, development and commercialization of highly innovative therapeutics to treat serious and rare diseases. All material long-lived assets of the Company reside in the United States. The Company does use contract research organizations (CROs) and research institutions located outside the United States. Some of these expenses are subject to collaboration reimbursement which is presented as a component of cost-sharing, net in the consolidated statements of operations and comprehensive loss. Cash, Cash Equivalents and Short-term and Long-term Investments The Company considers all highly liquid investments purchased with original maturities of 90 days or less at the date of acquisition to be cash equivalents. Cash and cash equivalents include cash held in banks and amounts held in interest-bearing money market accounts, as well as marketable securities with a remaining maturity of 90 days or less. Cash equivalents are carried at cost, which approximates their fair market value. The Company determines the appropriate classification of marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. The Company has classified all of its marketable securities at December 31, 2019 and 2018 as “available-for-sale” pursuant to ASC 320, Investments – Debt and Equity Securities. The Company records available-for-sale securities at fair value, with the unrealized gains and losses included in accumulated other comprehensive income (loss) in stockholders’ equity. There were no realized gains or losses on marketable securities for the years ended December 31, 2019 , 2018 and 2017 . Investments not classified as cash equivalents are presented as either short-term or long-term investments based on both their maturities as well as the time period the Company intends to hold such securities. The Company adjusts the cost of available-for-sale debt securities for amortization of premiums and accretion of discounts to maturity. The Company includes such amortization and accretion in interest income. The cost of securities sold is based on the specific identification method. The Company includes interest and dividends on securities classified as available-for-sale in interest income in the accompanying consolidated statements of operations and comprehensive loss. The Company reviews marketable securities for other-than-temporary impairment whenever the fair value of a marketable security is less than the amortized cost and evidence indicates that a marketable security’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the marketable security, or if it is more likely than not that the Company will be required to sell the marketable security before recovery of the amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, compliance with the Company’s investment policy, the severity and the duration of the impairment and changes in value subsequent to the end of the period. The aggregate fair value of securities held by the Company in an unrealized loss position for less than twelve months as of December 31, 2019 and December 31, 2018 was $35.8 million and $51.2 million , respectively. The aggregate fair value of securities held by the Company in an unrealized loss position for more than twelve months as of December 31, 2019 and December 31, 2018 was zero and $94.3 million , respectively. The aggregate unrealized loss for those securities in an unrealized loss position for more than twelve months was zero and $0.4 million , respectively. The Company evaluated its securities for other-than-temporary impairment and considered the decline in market value for the securities to be primarily attributable to current economic and market conditions. It is not more likely than not that the Company will be required to sell the securities, and the Company does not intend to do so prior to the recovery of the amortized cost basis. Based on this analysis, these marketable securities were not considered to be other-than-temporarily impaired as of December 31, 2019 and December 31, 2018 . Concentrations of Credit Risk and Off-Balance Sheet Risk The Company has no off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments that potentially subject the Company to concentrations of credit risk are primarily cash, cash equivalents, restricted cash, short-term and long-term investments and collaboration receivables. The Company maintains its cash and cash equivalent balances and short-term and long-term investments with financial institutions that management believes are creditworthy. Short-term and long-term investments consist of investment grade corporate obligations, treasury notes, asset backed securities, and certificates of deposit. The Company's investment policy includes guidelines on the quality of the institutions and financial instruments and defines allowable investments that the Company believes minimizes the exposure to concentrations of credit risk. The Company routinely assesses the creditworthiness of its customers and collaboration partners. The Company has not experienced any material losses related to receivables from individual customers and collaboration partners, or groups of customers. The Company does not require collateral. Due to these factors, no additional credit risk beyond amounts provided for collection losses is believed by management to be probable in the Company's collaboration receivables. Disclosure of Fair Value of Financial Instruments The Company's financial instruments include cash, cash equivalents, short-term and long-term investments, collaboration receivables, common stock warrants, accounts payable, and accrued expenses. See discussion below on the determination of the fair value of the Company's common stock warrants and short-term and long-term investments. The carrying value of the remainder of the Company's financial instruments approximated their fair values at December 31, 2019 and 2018 due to the short-term nature of these instruments. The Company has evaluated the estimated fair value of financial instruments using available market information and management's estimates. The use of different market assumptions and/or estimation methodologies could have a significant effect on the estimated fair value amounts. Fair Value Measurements ASC Topic 820, Fair Value Measurement (ASC 820), establishes a fair value hierarchy for instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company's own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company's assumptions about the inputs that market participants would use in pricing the asset or liability, and are developed based on the best information available in the circumstances. ASC 820 identifies fair value as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a three-tier fair value hierarchy that distinguishes between the following: • Level 1—Quoted market prices in active markets for identical assets or liabilities. • Level 2—Inputs other than Level 1 inputs that are either directly or indirectly observable, such as quoted market prices, interest rates, and yield curves. • Level 3—Unobservable inputs developed using estimates of assumptions developed by the Company, which reflect those that a market participant would use. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument's level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Items measured at fair value on a recurring basis include short-term and long-term investments (Note 5), and warrants to purchase common stock (Note 7). During the periods presented, the Company has not changed the manner in which it values assets and liabilities that are measured at fair value using Level 3 inputs. The following tables set forth the Company's financial instruments carried at fair value using the lowest level of input applicable to each financial instrument as of December 31, 2019 and 2018 (in thousands): December 31, 2019 Quoted Prices Significant Other Significant Total Assets: Money market funds $ 193,867 $ — $ — $ 193,867 Corporate obligations — 138,369 — 138,369 U.S. Treasury securities — 83,819 — 83,819 Certificates of deposit — 493 — 493 Mortgage and other asset backed securities — 12,470 — 12,470 Total assets $ 193,867 $ 235,151 $ — $ 429,018 Liabilities: Warrants to purchase common stock $ — $ — $ 1,856 $ 1,856 Total liabilities $ — $ — $ 1,856 $ 1,856 December 31, 2018 Quoted Prices Significant Other Significant Total Assets: Money market funds $ 74,023 $ — $ — $ 74,023 Corporate obligations — 128,920 — 128,920 U.S. Treasury securities — 56,978 — 56,978 Certificates of deposit — 1,715 — 1,715 Mortgage and other asset backed securities — 26,874 — 26,874 Total assets $ 74,023 $ 214,487 $ — $ 288,510 Liabilities: Warrants to purchase common stock $ — $ — $ 1,491 $ 1,491 Total liabilities $ — $ — $ 1,491 $ 1,491 The money market funds noted above are included in cash and cash equivalents in the accompanying consolidated balance sheets. The Company recognizes transfers between levels of the fair value hierarchy as of the end of the reporting period. There were no transfers within the hierarchy during the years ended December 31, 2019 and 2018 . The following table sets forth a summary of changes in the fair value of the Company's common stock warrant liabilities, which represent a recurring measurement that is classified within Level 3 of the fair value hierarchy, wherein fair value is estimated using significant unobservable inputs (in thousands): Year Ended December 31, 2019 2018 Beginning balance $ 1,491 $ 2,236 Change in fair value 365 52 Exercises — (797 ) Ending balance $ 1,856 $ 1,491 The fair value of the warrants to purchase common stock on the date of issuance and on each re-measurement date for those warrants classified as liabilities was estimated using either the Monte Carlo simulation framework, which incorporates future financing events over the remaining life of the warrants to purchase common stock, or for certain re-measurement dates, due to the warrants being deeply in the money, the Black-Scholes option pricing model. The Black-Scholes method of valuation involves using inputs such as the fair value of the Company's stock, stock price volatility, the contractual term of the warrants, risk-free interest rates, and dividend yields. At each reporting period the Company evaluates the best valuation methodology. At December 31, 2019 , and December 31, 2018 and December 31, 2017 , the Black-Scholes option pricing model was used. Due to the nature of these inputs, the valuation of the warrants is considered a Level 3 measurement. See Note 7 for further discussions of the accounting for the warrants. The Company measures eligible assets and liabilities at fair value, with changes in value recognized in earnings. Fair value treatment may be elected either upon initial recognition of an eligible asset or liability or, for an existing asset or liability, if an event triggers a new basis of accounting. The Company did not elect to remeasure any of its existing financial assets or liabilities, and did not elect the fair value option for any financial assets and liabilities transacted in the years ended December 31, 2019 or 2018 . Property and Equipment Property and equipment is stated at cost. Maintenance and repairs that do not improve or extend the lives of the respective assets are expensed to operations as incurred. Upon disposal, retirement or sale the related cost and accumulated depreciation is removed from the accounts and any resulting gain or loss is included in the results of operations. Depreciation and amortization is calculated using the straight-line method over the estimated useful lives of the assets, which are as follows: Asset Estimated Useful Life Computer equipment and software 3 years Office and laboratory equipment 3 years Leasehold improvements Shorter of the useful life or remaining lease term The Company reviews long-lived assets when events or changes in circumstances indicate the carrying value of the assets may not be recoverable. Recoverability is measured by comparison of the book values of the assets to future net undiscounted cash flows that the assets are expected to generate. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the book value of the assets exceed their fair value, which is measured based on the projected discounted future net cash flows arising from the assets. No impairment losses have been recorded during the years ended December 31, 2019 , 2018 and 2017 . Accrued and Prepaid Clinical Trial Expenses The Company accrues for estimated costs of research and development activities conducted by third-party service providers, which includes the conduct of clinical trials. The Company records the estimated costs of clinical trial activities based upon the estimated amount of services provided and includes the costs incurred but not yet invoiced within accrued liabilities on the balance sheet and within research and development expense in the consolidated statements of operations and comprehensive loss. Invoicing from third-party service providers may not coincide with actual work performed and can result in the Company being in a prepaid position at period end. These costs can be a significant component of the Company's research and development expenses. The Company estimates the amount of services provided and efforts expended pursuant to quotes and contracts with third parties, as well as discussion with internal personnel and external service providers as to the progress of the services and the agreed-upon fee to be paid for such services. The Company makes significant judgments and estimates in determining the services incurred as of the balance sheet date, which may result in either an accrual or prepaid balance. As actual costs become known, it adjusts its estimates. Although the Company does not expect its estimates to be materially different from amounts actually incurred, its understanding of the status and timing of services performed, the number of subjects enrolled, and the rate of enrollment may vary from its estimates and could result in the Company reporting amounts that are too high or too low in a particular period. The Company's accrued and prepaid expenses are dependent, in part, upon the receipt of timely and accurate reporting from contract research organizations and third-party service providers. To date, the Company has not experienced any material differences between its estimated costs and actual costs incurred. Revenue Recognition Effective January 1, 2018, the Company adopted Accounting Standards Codification Topic 606, Revenue from Contracts with Customers , (ASC 606), using the modified retrospective transition method. Under this method, results for reporting periods beginning January 1, 2018 are presented under ASC 606, while prior period amounts are not adjusted and continue to be reported in accordance with ASC 605. The Company has primarily generated revenue through collaboration, license and research arrangements, which are within the scope of ASC 606, with collaboration partners for the development and commercialization of therapeutic candidates. The arrangements generally contain performance obligations, which may include (1) licenses, or options to obtain licenses, to the Company's technology, (2) research and development activities performed for the collaboration partners (3) participation on joint development committees (JDCs), and (4) the manufacturing of clinical or preclinical material. Payments pursuant to these arrangements typically include non-refundable, upfront payments, milestone payments upon achieving significant development events, research and development reimbursements, sales milestones, exercises of options, and royalties on future product sales. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company's consolidated balance sheets. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, current portion. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, net of current portion. Amounts recognized as revenue, but not yet received or invoiced are generally recognized as contract assets, including collaboration receivables. To determine revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with the customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract, determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. Depending on the nature of the performance obligation these assessments require management to make judgments and estimates. Exclusive Licenses If the license to the Company’s intellectual property is determined to be distinct from the other promises or performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, upfront fees allocated to the license when the license is transferred and the customer is able to use and benefit from the license. In order to assess whether the license is distinct, the Company considers the capabilities of the collaboration partner and the availability of the necessary expertise in the general marketplace to determine whether the collaboration partner can benefit from the license for its intended purpose without the receipt of the remaining elements. For licenses determined not to be distinct the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. The measure of progress, and thereby periods over which revenue should be recognized, are subject to estimates by management and may change over the course of the research and development and licensing agreement. Research and Development Services The promises under the Company’s collaboration and license agreements generally include research and development services to be performed by the Company on behalf of the collaboration partner. As the provision of research and development services is a part of the Company’s central operations, when the Company is principally responsible for the performance of these services under the agreements, the Company recognizes revenue on a gross basis for research and development services in accordance with the ASC 606 framework described above. Customer Options The Company's agreements may contain options which provide the collaboration partner the right to obtain additional licenses. If an arrangement is determined to contain customer options, the goods and services underlying the customer options are not considered to be performance obligations at the inception of the arrangement, and the associated option fees are not included in the transaction price. The Company evaluates the customer options to determine if they represent material rights, which may include options to acquire additional goods or services for free or at a discount. If the customer options are determined to represent a material right, the material right is recognized as a separate performance obligation at the outset of the arrangement. The Company allocates the transaction price to material rights based on the relative standalone selling price, which is determined based on the identified discount and the probability that the customer will exercise the option. Amounts allocated to a material right are not recognized as revenue until, at the earliest, the option is exercised. Milestone Payments At the inception of each arrangement that includes milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. The Company evaluates factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the respective milestone in making this assessment. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. If a milestone or other variable consideration relates specifically to the Company's efforts to satisfy a single performance obligation or to a specific outcome from satisfying the performance obligation, the Company generally allocates the milestone amount entirely to that performance obligation. Royalties For arrangements that include sales-based royalties, including milestone payments based on a level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has recognized minimal royalty revenue resulting from any of its licensing arrangements. Research and Development Expenses Research and development costs are charged to expense as costs are incurred in performing research and development activities. Research and development costs include all direct costs, including salaries, stock compensation and benefits for research and development personnel, outside consultants, costs of clinical trials, costs related to acquiring and manufacturing clinical study materials, sponsored research, clinical trials insurance, other outside costs, depreciation and facility costs related to the development of drug candidates. The Company records upfront, non-refundable payments made to outside vendors, or other payments made in advance of services performed or goods being delivered, as prepaid expenses, which are expensed as services are performed or the goods are delivered. Certain research and development projects are, or have been, partially funded by collaboration agreements, and the expenses related to these activities are included in research and development costs. The Company records the related reimbursement of research and development costs under these agreements as revenue, as more fully described above and in Note 10. Stock-Based Compensation At December 31, 2019 , the Company had two stock-based compensation plans, which are more fully described in Note 11. The Company accounts for stock-based compensation in accordance with the provisions of ASC Topic 718, Compensation—Stock Compensation (ASC 718), which requires the recognition of expense related to the fair value of stock-based compensation awards in the consolidated statements of operations and comprehensive loss. For stock-based awards issued to employees and members of the Company's board of directors (the Board) for their services on the Board and for participation in the employee stock purchase plan, the Company estimates the grant date fair value of each option award using the Black-Scholes option pricing model. The use of the Black-Scholes option pricing model requires management to make assumptions with respect to the expected term of the option, the expected volatility of the common stock consistent with the expected life of the option, risk-free interest rates and expected dividend yields of the common stock. For awards subject to service-based vesting conditions, the Company recognizes stock-based compensation expense, equal to the grant date fair value of stock options on a straight-line basis over the requisite service period, which is generally the vesting term. For awards subject to both performance and service-based vesting conditions, the Company recognizes stock-based compensation expense using an accelerated recognition method when it is probable that the performance condition will be achieved. If achievement of the performance condition is not probable, but the award will vest based on the service condition, expense is recognized over the requisite service period. In July 2018, the Company early adopted ASU 2018-07, which expands the scope of Topic 718 to include share-based payments to non-employees. In connection with the adoption of this standard, the Company changed its accounting policy to establish the fair value of awards to non-employees at adoption date for existing awards and at grant date for new awards, rather than to mark such awards to market through the vesting period of the award. Additionally under the new guidance, the Company uses qualitative factors, such as exercise behavior and expected term to establish the term of the awards, rather than using contractual term, when valuing the awards. Forfeitures are recognized as they occur. See Note 11 for a discussion of the assumptions used by the Company in determining the grant date fair value of options granted under the Black-Scholes option pricing model, as well as a summary of the stock option activity under the Company's stock-based compensation plans for the year ended December 31, 2019 . Income Taxes Income taxes are recorded in accordance with ASC Topic 740, Income Taxes (ASC 740), which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the |
Property and Equipment, Net
Property and Equipment, Net | 12 Months Ended |
Dec. 31, 2019 | |
Property, Plant and Equipment [Abstract] | |
Property and Equipment, Net | Property and Equipment, Net Property and equipment, net, consists of the following (in thousands): December 31, 2019 2018 Computer equipment and software $ 1,767 $ 1,712 Office equipment 672 672 Laboratory equipment 22,079 19,948 Leasehold improvements 12,347 11,668 Construction in progress 1,181 1,139 Total property and equipment 38,046 35,139 Accumulated depreciation and amortization (31,234 ) (28,033 ) Property and equipment, net $ 6,812 $ 7,106 Depreciation and amortization expense was $3.9 million , $3.7 million and $2.8 million for the years ending December 31, 2019 , 2018 and 2017 , respectively. |
Restricted Cash
Restricted Cash | 12 Months Ended |
Dec. 31, 2019 | |
Cash and Cash Equivalents [Abstract] | |
Restricted Cash | Restricted Cash The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheet that sum to the total of the same such amounts shown in the statement of cash flows (in thousands): December 31, 2019 2018 2017 Cash and cash equivalents $ 237,677 $ 144,052 $ 100,150 Restricted cash 1,597 1,597 1,132 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 239,274 $ 145,649 $ 101,282 As of December 31, 2019 , 2018 , and 2017 , the Company maintained letters of credit totaling $1.6 million , $1.6 million and $1.1 million , respectively, held in the form of certificates of deposit as collateral for the Company's facility lease obligations and its credit cards. |
Cash, Cash Equivalents and Shor
Cash, Cash Equivalents and Short-term and Long-term Investments | 12 Months Ended |
Dec. 31, 2019 | |
Cash and Cash Equivalents [Abstract] | |
Cash, Cash Equivalents and Short-term and Long-term Investments | Cash, Cash Equivalents and Short-term and Long-term Investments The following is a summary of cash, cash equivalents and available-for-sale securities as of December 31, 2019 and December 31, 2018 (in thousands): December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Cash and cash equivalents due in 90 days or less $ 237,677 $ — $ — $ 237,677 Available-for-sale securities: Corporate obligations 124,676 219 (15 ) 124,880 U.S. Treasury securities 78,230 98 (1 ) 78,327 Certificates of deposit 490 3 — 493 Mortgage and other asset backed securities 12,476 5 (12 ) 12,469 Total available-for-sale securities $ 215,872 $ 325 $ (28 ) $ 216,169 Total cash, cash equivalents and available-for-sale securities $ 453,549 $ 325 $ (28 ) $ 453,846 December 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Cash and cash equivalents due in 90 days or less $ 144,064 $ — $ (12 ) $ 144,052 Available-for-sale securities: Corporate obligations due in one year or less 73,671 — (267 ) 73,404 U.S. Treasury securities due in one year or less 45,346 — (79 ) 45,267 Certificates of deposit due in one year or less 1,715 — — 1,715 Mortgage and other asset backed securities due in one year or less 26,982 — (108 ) 26,874 Total available-for-sale securities $ 147,714 $ — $ (454 ) $ 147,260 Total cash, cash equivalents and available-for-sale securities $ 291,778 $ — $ (466 ) $ 291,312 |
Accrued Expenses
Accrued Expenses | 12 Months Ended |
Dec. 31, 2019 | |
Payables and Accruals [Abstract] | |
Accrued Expenses | Accrued Expenses Accrued expenses consist of the following (in thousands): December 31, 2019 2018 Research and development $ 11,844 $ 8,144 Commercial 1,027 — Employee compensation 9,932 7,975 Professional services 976 621 Accrued purchases 119 351 Other 997 1,118 Total accrued expenses $ 24,895 $ 18,209 |
Warrants
Warrants | 12 Months Ended |
Dec. 31, 2019 | |
Warrants and Rights Note Disclosure [Abstract] | |
Warrants | Warrants Below is a summary of the number of shares issuable upon exercise of outstanding warrants and the terms and accounting treatment for the outstanding warrants (in thousands, except per share data): Warrants as of Weighted- Average Exercise Balance Sheet Classification December 31, 2019 December 31, 2018 Price Per Share Expiration December 31, 2019 December 31, 2018 Warrants to purchase common stock 39 39 $ 5.88 June 10, 2020 - July 9, 2020 Liability Liability All warrants 39 39 $ 5.88 ______________________________________________________________________ Upon issuance the Company concluded the anti-dilution feature required the warrants to be classified as liabilities under ASC Topic 815, Derivatives and Hedging—Contracts in Entity's Own Equity (ASC 815). The warrants are measured at fair value, with changes in fair value recognized as a gain or loss to other income (expense) in the consolidated statements of operations and comprehensive loss for each reporting period thereafter. At the end of each reporting period, the Company remeasures the fair value of the outstanding warrants until they are exercised or expire. All outstanding warrants were fully vested and exercisable as of December 31, 2019 . |
Commitments and Contingencies
Commitments and Contingencies | 12 Months Ended |
Dec. 31, 2019 | |
Commitments and Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | Commitments and Contingencies Operating Leases The Company leases its facilities under non-cancelable operating leases that expire at various dates through September 2024. All of the Company's leases contain escalating rent clauses, which require higher rent payments in future years. Prior to 2019, the Company recognized rent expense, calculated as the remaining cost of the lease allocated over the remaining lease term on a straight line basis, as well as deferred rent for certain lease incentives, amortized as a reduction of rent expense over the life of the lease. As of January 1, 2019, the Company adopted Accounting Standards Codification Topic 842, Leases (ASC 842 ), which requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by leases. As a result of this adoption, the Company recorded a right-of-use asset and corresponding lease liability on the consolidated balance sheet as of December 31, 2019. The Company continues to recognize rent expense, which is calculated as the remaining cost of the lease allocated over the remaining lease term on a straight-line basis. Refer to Footnote 14 for additional information regarding the Company's operating leases. Legal Proceedings The Company, from time to time, may be party to litigation arising in the ordinary course of its business. Except as discussed below, the Company was not subject to any material legal proceedings during the years ended December 31, 2019 , 2018 and 2017 , and, to the best of its knowledge, no material legal proceedings are currently pending or threatened. Other The Company is also party to various agreements, principally relating to licensed technology, that require future payments relating to milestones not met at December 31, 2019 and 2018 , or royalties on future sales of specified products. See Note 10 for discussion of these arrangements. The Company enters into standard indemnification agreements in the ordinary course of business. Pursuant to the agreements, the Company indemnifies, holds harmless, and agrees to reimburse the indemnified party for losses suffered or incurred by the indemnified party, generally the Company's business partners or customers, in connection with any U.S. patent or any copyright or other intellectual property infringement claim by any third party with respect to the Company's products. The term of these indemnification agreements is generally perpetual any time after execution of the agreement. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is unlimited. The Company has never incurred costs to defend lawsuits or settle claims related to these indemnification agreements. |
Stockholders' Equity
Stockholders' Equity | 12 Months Ended |
Dec. 31, 2019 | |
Stockholders' Equity Note [Abstract] | |
Stockholders' Equity | Stockholders' Equity On September 25, 2017, the Company completed the sale of 5,405,406 shares of common stock at a public offering price of $37.00 per share. On October 4, 2017, in connection with the September 2017 public offering, the underwriters fully exercised their option to purchase an additional 810,810 shares of common stock. The total net proceeds to the Company from the September 2017 public offering and the underwriters' exercise of their option to purchase additional shares of common stock was $215.8 million . On January 18, 2019, the Company completed the sale of 5,348,838 shares of common stock at a public offering price of $43.00 per share, resulting in net proceeds to the Company of approximately $215.8 million . In connection with the January 2019 public offering, on February 12, 2019, the underwriters fully exercised their option to purchase an additional 802,325 shares of common stock. The total net proceeds to the Company from the January 2019 public offering and the underwriters' exercise of their option to purchase additional shares of common stock was $248.2 million . Preferred Stock The Company’s certificate of incorporation authorizes the Board to issue up to 25,000,000 shares of preferred stock from time to time in one or more series. The rights, preferences, restrictions, qualifications and limitations of such stock are determined by the Board. As of December 31, 2019 no preferred shares are issued or outstanding. Common Stock The holders of shares of common stock are entitled to one vote for each share of common stock held at all meetings of stockholders and written actions in lieu of meetings. The holders of shares of common stock are entitled to receive dividends, if and when declared by the Board. No dividends have been declared or paid by the Company through December 31, 2019 . Common Stock Reserved for Future Issuance At December 31, 2019 , the Company has reserved for future issuance the following number of shares of common stock (in thousands): December 31, 2019 Outstanding stock options to purchase common stock 3,820 Outstanding restricted stock units 397 Shares available for future issuance under equity incentive plan 4,634 Warrants to purchase common stock 39 Shares available for future issuance under the employee stock purchase plan 123 Additional shares reserved for unissued, but designated, Preferred Stock 25,000 Total shares of authorized common stock reserved for future issuance 34,013 |
Significant Agreements
Significant Agreements | 12 Months Ended |
Dec. 31, 2019 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Significant Agreements | Significant Agreements BMS (Bristol-Myers Squibb Company) Overview On February 20, 2008 the Company entered into an agreement with Celgene, which was acquired by BMS in November 2019 and is now referred to herein as BMS, relating to sotatercept (the Original Sotatercept Agreement), which was amended on August 2, 2011 (as amended, the Amended Sotatercept Agreement). The Company further amended and restated the Original Sotatercept Agreement in its entirety on September 18, 2017, (the Restated Sotatercept Agreement). On August 2, 2011 the Company entered into a second agreement with BMS for REBLOZYL® (luspatercept-aamt) (the REBLOZYL Agreement, formerly the Luspatercept Agreement). Restated Sotatercept Agreement The Restated Sotatercept Agreement provides BMS with an exclusive license to sotatercept outside of the field of pulmonary hypertension, referred to as the PH field, and provides the Company with the worldwide rights to develop and commercialize sotatercept in the PH field. In connection with the Restated Sotatercept Agreement, BMS agreed not to develop or commercialize in the PH field any compound developed under the Restated Sotatercept Agreement or the REBLOZYL Agreement, and the Company agreed not to develop or commercialize any compound developed under the Restated Sotatercept Agreement or the REBLOZYL Agreement in any field outside the PH field. The Company has the right to license, transfer or sell its rights to develop and commercialize sotatercept in the PH field, subject to BMS's right of first negotiation. The Company is responsible for 100% of the costs related to its development and commercialization of sotatercept in the PH field. If sotatercept is commercialized to treat pulmonary hypertension and the Company recognizes such revenue, then BMS will be eligible to receive a royalty in the low 20% range on global net sales. In certain circumstances BMS may recognize revenue related to the commercialization of sotatercept in the PH field, and in this scenario, the Company will be eligible to receive a royalty from BMS such that the economic position of the parties is equivalent to the scenario in which the Company recognizes such revenue. With respect to the development and commercialization of sotatercept outside of the PH field or the development and commercialization of any other compound under the Restated Sotatercept Agreement, the terms of the Amended Sotatercept Agreement, described below, remained unchanged. Pursuant to the Restated Sotatercept Agreement, BMS will provide the Company with certain quantities of their existing clinical supply of sotatercept for development in the PH field at no cost. For clinical supply of sotatercept in excess of that which is agreed to under the Restated Sotatercept Agreement, BMS had the option to provide the Company with such clinical supply of sotatercept, but has declined this option, and the Company is responsible for manufacturing future clinical supply of sotatercept in the PH field. BMS may elect, however, to provide the Company with commercial supply of sotatercept at a negotiated price or provide a tech transfer to enable the Company to manufacture on its own behalf. The conduct of the collaboration is managed by a Joint Development Committee (JDC) and Joint Commercialization Committee (JCC). In the event of a deadlock of a committee, the Company shall determine the resolution of issues specifically related to the PH field, (other than pricing which shall be determined by consensus), and BMS shall determine the resolution of all other issues. The JCC will oversee commercialization of sotatercept, and sotatercept pricing will be determined by mutual agreement of the Company and BMS in the JCC. The Restated Sotatercept Agreement will expire on a country-by-country basis on the occurrence of the latest to occur of the following: (1) the expiration of the royalty term with respect to all licensed products outside the PH field in such country, (2) the expiration of the royalty term with respect to all sotatercept licensed products in the PH field in such country, and (3) the exercise or forfeiture by BMS of its option with regard to each option compound. In the PH field, the royalty term for each licensed product in each country is the period commencing with first commercial sale of the applicable licensed product in the applicable country and ending on the latest of expiration of specified patent coverage or a specified period of years. Outside the PH field, the royalty term for each licensed product in each country outside North America is the period commencing with first commercial sale of the applicable licensed product in the applicable country and ending on the latest of expiration of specified patent coverage or a specified period of years, and the royalty term for each licensed product in North America is the period commencing with the first commercial sale in North America and ending, on a licensed product and country-by-country basis on the date which commercialization of such licensed product has ceased. The term for each option compound runs for a specified period of years unless BMS exercises its option, in which case the compound becomes a licensed product, or forfeits its option by failing to make certain payments following the achievement of certain milestones in early clinical development of the option compound. The Restated Sotatercept Agreement is terminable by either party upon a breach that is uncured and continuing or by BMS for convenience on a country-by-country or product-by-product basis, or in its entirety. BMS may also terminate the Restated Sotatercept Agreement, in its entirety or on a product-by-product basis, for failure of a product to meet a development or clinical trial endpoint. Termination for cause by the Company or termination by BMS for convenience or failure to meet an endpoint will have the effect of terminating the applicable license to BMS and the rights granted to the Company with respect to the development of sotatercept in the PH field shall become irrevocable. Termination for cause by either party shall result in reducing the remaining royalties due to the breaching party by a certain percentage. Upon termination by BMS for convenience or for failure to meet an endpoint, the Company and BMS will enter into a termination agreement pursuant to which, among other things, BMS will continue to be eligible to receive a royalty in the low 20% range on global net sales of sotatercept in the PH field. The Company was not required to make any upfront payments to BMS upon execution of the Restated Sotatercept Agreement, and is not required to make any milestone payments to BMS in connection with its development and commercialization of sotatercept in the PH field. Original and Amended Sotatercept Agreement Under the Original Sotatercept Agreement, as preserved by the Amended Sotatercept Agreement, the Company granted BMS an exclusive license to sotatercept in all indications and an option to license discovery stage compounds against three specified targets. BMS paid $45.0 million of nonrefundable, upfront license and option payments to the Company and bought $5.0 million of equity upon closing in February 2008. Per the Original Sotatercept Agreement, concurrent with the Company's 2013 IPO, BMS purchased an additional $10.0 million of the Company's common stock. The Company retained responsibility for research and development of sotatercept through the end of Phase 2a clinical trials, as well as manufacturing the clinical supplies for these trials. These activities were substantially completed in 2011. BMS will be responsible for any sotatercept Phase 3 clinical trials, as well as any additional Phase 2 clinical trials and is responsible for manufacturing or overseeing the manufacture of Phase 3 and commercial supplies outside of the PH field. Commensurate with the execution of the REBLOZYL Agreement described below, in August 2011 the Company and BMS agreed to modify the terms of the collaboration. Outside of the PH field, the significant financial terms of the Amended Sotatercept Agreement, which were preserved in the Restated Sotatercept Agreement, are: • Since January 1, 2013, BMS has been responsible for paying 100% of worldwide development costs for the sotatercept program; • BMS will be responsible for all commercialization costs worldwide as agreed in the budget between the Company and BMS; • The Company is eligible to receive tiered royalty payments in the low-to-mid 20% percent range on net sales of sotatercept subject to certain reductions, including for entry of a generic product onto the market; and • The Company has the right to co-promote sotatercept and future products in all fields, in each case if approved, in North America, and BMS will pay all costs related thereto. The Amended Sotatercept Agreement, as preserved in the Restated Sotatercept Agreement, contains a two-category contingent development milestone structure outside of the PH field (oncology and non-oncology) for sotatercept, including future clinical milestones of up to $27.0 million , regulatory milestones of up to $190.0 million and commercial milestones of up to $150.0 million . Additionally, the Company is eligible to receive option fees of up to $30.0 million for each of the three discovery-stage targets, and for all three discovery-stage targets in the aggregate, clinical milestones of up to $25.5 million , regulatory milestones of up to $142.5 million and commercial milestones of up to $150.0 million . None of the three discovery stage programs has advanced to the stage to achieve payment of a milestone, nor does the Company expect any such milestone payments in the near future. REBLOZYL Agreement Under the terms of the REBLOZYL Agreement, the Company and BMS collaborate worldwide for the joint development and commercialization of REBLOZYL. The Company also granted BMS an option for future products for which Acceleron files an Investigational New Drug application for the treatment of anemia. BMS paid $25.0 million on the closing of the REBLOZYL Agreement in August 2011. The Company retained responsibility for research and development through the end of Phase 1 and the Company's initial luspatercept-aamt beta-thalassemia and MDS Phase 2 clinical trials, as well as manufacturing the clinical supplies for these studies. BMS will conduct subsequent Phase 2 and Phase 3 clinical studies and will be responsible for overseeing the manufacture of Phase 3 and commercial supplies by third party contract manufacturing organizations. The significant financial terms of the REBLOZYL Agreement are: • Since January 1, 2013, BMS has been responsible for paying 100% of worldwide development costs for the REBLOZYL program; • BMS is responsible for all commercialization costs worldwide as agreed in the budget between the Company and BMS; • The Company is eligible to receive tiered royalty payments in the low-to-mid 20% percent range on net sales of REBLOZYL subject to certain reductions, including for entry of a generic product onto the market; and • The Company has the right to co-promote REBLOZYL and future products in all fields, in each case if approved, in North America, and BMS will pay all costs related thereto, as agreed in the budget between the Company and BMS. Per the terms of the agreement, the Company was eligible to receive total clinical milestones of up to $32.5 million , regulatory milestones of up to $105.0 million and commercial milestones of up to $80.0 million for REBLOZYL. The Company will receive additional, lower development, regulatory, and commercial milestones for any additional products for the treatment of anemia on which BMS exercises an option. As of December 31, 2019 , the Company is eligible to receive remaining future regulatory and commercial milestones of up to $125.0 million for the REBLOZYL program. Additionally, activities that the Company elects to conduct outside of the approved budgets to support REBLOZYL are at the Company's expense. The REBLOZYL Agreement will expire on a country-by-country basis on the occurrence of both of the following: (1) the expiration of the royalty term with respect to all license products in such country, and (2) the end of the option term. The royalty term for each licensed product in each country outside North America is the period commencing with first commercial sale of the applicable licensed product in the applicable country and ending on the latest of expiration of specified patent coverage or a specified period of years. The royalty term for each licensed product in North America is the period commencing with the first commercial sale in North America and ending, on a licensed product and country-by-country basis on the date which commercialization of such licensed product has ceased. The option term runs until the later of (1) the date on which no development or commercialization activities are ongoing or are expected to commence for any licensed products under the REBLOZYL Agreement; (2) the date on which no development or commercialization activities are ongoing or are expected to commence for any licensed products under the Restated Sotatercept Agreement and all option rights under the Restated Sotatercept Agreement have been forfeited with respect to each option compound where BMS has made a payment with respect to such compound; and (3) the royalty term for all licensed products under the REBLOZYL Agreement and the Restated Sotatercept Agreement has ended; provided that if at the time the option term would otherwise end any option compounds under the REBLOZYL Agreement are in clinical development the option term shall continue until BMS's rights to such compound are either exercised or forfeited. BMS has the right to terminate the REBLOZYL Agreement with respect to one or more licensed targets or in its entirety, upon 180 days ' notice (or 45 days ' notice if the licensed product has failed to meet certain end point criteria with respect to clinical trials or other development activities). The agreement may also be terminated in its entirety by either BMS or the Company in the event of a material breach by the other party or in the event of a bankruptcy filing of the other party. There are no cancellation, termination or refund provisions in this arrangement that contain material financial consequences to the Company. Accounting Analysis The Company initially accounted for these arrangements pursuant to FASB ASC Topic 605, Revenue Recognition. As indicated in Note 2, the Company adopted ASC 606 on January 1, 2018 using the modified retrospective transition method, which resulted in a cumulative-effect reduction to accumulated deficit of $3.7 million . The most significant change in the Company’s accounting policy upon adoption of ASC 606 related to the evaluation of milestone revenue pursuant to its arrangements with BMS. In accordance with ASC 605, at the inception of each arrangement that included milestone payments, the Company evaluated, with respect to each milestone, whether the milestone was substantive and at-risk. The Company recognized the milestone payment upon achievement, assuming all other revenue recognition criteria were met, or over the remaining service period if not deemed substantive and at-risk. Pursuant to ASC 606, at inception and each subsequent reporting period, the Company evaluates whether the milestones are probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. The change in guidance noted above could result in earlier recognition of milestones pursuant to the Company's arrangements. The Company identified the following material promises under the Restated Sotatercept Agreement and REBLOZYL Agreement: (1) licenses to develop and commercialize sotatercept and REBLOZYL; (2) performance of research and development services; (3) participation in the JDCs; and (4) the performance of the manufacturing services. The Company determined that the licenses to sotatercept and REBLOZYL technology, the research and development activities, participation in the JDCs and the manufacturing services are each distinct performance obligations. The option rights to future products related to the treatment of anemia under the REBLOZYL Agreement are not considered to represent a material right as this right is a protective provision akin to exclusivity and does not represent a customer option to receive the rights or services at a discount. In addition, the Company is under no obligation to discover, develop, or deliver any new compounds that modulate anemia. Therefore, the option right under the REBLOZYL Agreement is not a performance obligation. Commercialization support for each of sotatercept and REBLOZYL is considered to be a participatory right and not a performance obligation. The Company concluded that services provided for the extension studies do not represent a contract modification or a performance obligation but rather a separate services arrangement, which is accounted for as a separate contract. Each study includes one promise, the completion of the study, which is distinct from the performance obligations in the Restated Sotatercept Agreement and REBLOZYL Agreement that is satisfied over time, and the consideration for each study approximates the stand-alone selling price. Revenue is recognized as the services for each study are provided for the extension studies. The transaction price includes the following payments received under the Restated Sotatercept and REBLOZYL Agreement through the adoption date for a total of $192.3 million , as follows: • $25.0 million upfront fee in connection with the closing of the REBLOZYL Agreement; • $45.0 million of nonrefundable, upfront license and option payments in connection with the closing of the Original and Amended Sotatercept Agreements; • $14.9 million received for sotatercept development and manufacturing activities; • $47.9 million received for REBLOZYL development and manufacturing activities; and • $59.5 million milestone payments pursuant to the agreements. The Company allocated the total transaction price to the identified performance obligations (both satisfied and unsatisfied) using the estimated standalone selling price of each performance obligation as of the adoption date of ASC 606. The Company’s estimate of the standalone selling price requires judgment, in particular in estimating the value of the license rights for REBLOZYL and sotatercept, which includes assumptions over the projected revenues and expenses, probability of technical and regulatory success and appropriate discount rates. As of the ASC 606 adoption date, the only remaining undelivered element was participation in the Joint Development Committee (JDC). The transaction price allocated to participation on the JDC based on the established standalone selling price of all performance obligations was de minimis as the sotatercept and REBLOZYL licenses carried the most significant portion of the value included in the agreements, and the Company's remaining effort on the JDC is minimal. Therefore, the Company recorded a cumulative-effect reduction to accumulated deficit of $3.7 million as the adoption date and a corresponding decrease to deferred revenue, of which $0.5 million was recorded to current deferred revenue and $3.2 million was recorded to long-term deferred revenue. Upon adoption of ASC 606, all future potential milestone payments were excluded from the transaction price as they were still subject to completion of on-going clinical studies or other risks that are outside of the Company's control and therefore the risk of significant reversal has not been resolved. As of December 31, 2019 , the next milestone payment for REBLOZYL would be $25.0 million and would result from European Medicines Agency (EMA) approval of a Biologics Licensing Application (BLA) or equivalent for luspatercept-aamt in either myelodysplastic syndromes or beta-thalassemia. The Company and BMS expect the EMA to issue a decision on the approval of the MAA in the second half of 2020. In accordance with the Company's accounting policy regarding revenue recognition as described in Note 2, the revenue associated with this milestone will be recognized once it is probable that the application is approved by the regulatory authority. Milestone payments that are not within the control of the Company or the licensee are not considered probable of being achieved until those approvals are received. The approval of the application is not within the control of the Company or the licensee, and therefore, as of December 31, 2019 , the Company cannot determine if it is probable that a regulatory agency will approve the applications. On June 4, 2019, the Company and BMS announced that the U.S. Food and Drug Administration (FDA) accepted BMS's Biologics Licensing Application (BLA), and the European Medicines Agency (EMA) validated BMS's marketing authorization application (MAA), for luspatercept-aamt for both myelodysplastic syndrome and beta-thalassemia. As a result, the $25.0 million milestone for acceptance of the BLA by the FDA or EMA for use of a Licensed Product is no longer constrained. Additionally, on November 8, 2019, the Company and BMS announced that the FDA approved REBLOZYL for the treatment of anemia in adult patients with beta-thalassemia who require regular red blood cell transfusions. As a result, the $35.0 million milestone for approval of the BLA for REBLOZYL was no longer constrained. As the Company does not have any remaining performance obligations under the agreement with BMS, the full $60.0 million was recognized during the year ended December 31, 2019 . Through December 31, 2019 , under all BMS arrangements the Company has received net cost-share payments and milestones of $181.9 million and $44.7 million for REBLOZYL and sotatercept, respectively. The Company recorded net cost-sharing revenue of $14.0 million , $14.0 million , and $12.9 million during the years ended December 31, 2019 , 2018 , and 2017 , respectively. Other Agreements Other In 2004, the Company entered into a license agreement with a non-profit institution for an exclusive, sublicensable, worldwide, royalty-bearing license to certain patents developed by the institution (Primary Licensed Products). In addition, the Company was granted a non-exclusive, non-sub-licensable license for Secondary Licensed Products. The Company agreed to pay specified development milestone payments totaling up to $2.0 million for sotatercept and $0.7 million for REBLOZYL. In addition, the Company is obligated to pay milestone fees based on the Company's research and development progress, and U.S. sublicensing revenue ranging from 10% - 25% , as well as a royalty ranging from 1.0% - 3.5% of net sales on any products developed under the licenses. During the years ended December 31, 2019 , 2018 and 2017 , the Company paid and expensed milestones and fees defined under the agreement totaling $3.7 million , $0.1 million and $0.1 million , respectively, which is recorded as research and development expense. For further discussion on this agreement, see the description in the “Business - In-Licenses” section of this Annual Report on Form 10-K. In May 2014, the Company executed a collaboration agreement with a research technology company. The Company paid an upfront research fee of $0.3 million upon execution of the agreement. The Company also received an option to obtain a commercial license to the molecules developed during the collaboration. During the years ended December 31, 2019 , 2018 , and 2017 , the Company expensed milestones and fees totaling $2.1 million , $0.1 million , and $1.6 million , which is recorded as research and development expense. In December 2019, the Company executed a license and collaboration agreement with Fulcrum Therapeutics to identify small molecules designed to modulate specific pathways associated with a targeted indication within the pulmonary disease space. The Company paid an upfront research fee of $10.0 million upon execution of the agreement. The Company also agreed to pay specified research, development and commercial milestone payments of up to $295.0 million for a first product commercialized and up to a maximum of $143.5 million in additional milestone payments for all subsequent products commercialized. Fulcrum will additionally receive tiered royalty payments in the mid-single-digit to low double-digit range on net sales, as well as reimbursement for relevant research and development costs. During the year ended December 31, 2019 , the Company expensed the upfront fee of $10.0 million , which is recorded as research and development expense. |
Stock-Based Compensation
Stock-Based Compensation | 12 Months Ended |
Dec. 31, 2019 | |
Share-based Payment Arrangement [Abstract] | |
Stock-Based Compensation | Stock-Based Compensation At December 31, 2019 , the Company had two stock-based compensations plans, which are more fully described below. The Company's 2003 Stock Option and Restricted Stock Plan (the 2003 Plan) provided for the issuance of stock options and restricted stock to employees, officers, directors, consultants and key personnel of the Company as determined by the Board. In conjunction with the effectiveness of the 2013 Equity Incentive Plan (the 2013 Plan) described below, the Company determined that no further stock options or other equity-based awards may be granted under the 2003 Plan. On September 4, 2013, the Board and stockholders approved the adoption of the 2013 Equity Incentive Plan (the 2013 Plan), which provides for the issuance of stock options, restricted stock units, and other equity-based awards. The Company has reserved for issuance an aggregate of 1,500,000 shares of common stock under the 2013 Plan which is comprised of (i) the remaining 155,884 shares reserved for issuance under the 2003 Plan and (ii) an additional 1,344,116 shares. The 2013 Plan provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning in 2014, by the lesser of (i) 3,150,000 shares, or (ii) 4% of the outstanding number of shares of the Company's common stock on the immediately preceding December 31st. This number is subject to adjustment in the event of a stock split, stock dividend or other change in the Company's capitalization. The number of shares underlying equity awards available for future grant was 4,634,133 at December 31, 2019 . The Company has not granted unrestricted stock awards under the 2003 Plan or the 2013 Plan since its inception. Stock options carry an exercise price equal to the estimated fair value of the Company's common stock on the date of grant. Options generally expire 10 years following the date of grant. Stock options typically vest over 4 years , and restricted stock units typically vest over 3 years , but vesting provisions can vary based on the discretion of the Board. Shares of the Company's common stock underlying any awards that are forfeited, canceled, withheld upon exercise of an option, or settlement of an award to cover the exercise price or tax withholding, reacquired by the Company prior to vesting, satisfied without the issuance of shares of the Company's common stock, or otherwise terminated other than by exercise will be added back to the shares of common stock available for issuance under the 2013 Plan. Shares available for issuance under the 2013 Plan may be authorized but unissued shares of the Company's common stock or shares of the Company's common stock that have been reacquired by the Company. Additionally, on September 4, 2013, the Board and stockholders approved the adoption of the 2013 Employee Stock Purchase Plan (the 2013 ESPP). Under the 2013 ESPP, 275,000 shares of the Company's common stock will be available for issuance to eligible employees. The per-share purchase price at the end of each offering period is equal to 85% of the closing price of one share of the Company’s common stock at the beginning or end of the offering period, whichever is lower, subject to Internal Revenue Service limits. The 2013 ESPP will terminate on September 4, 2023, the tenth anniversary of the initial adoption of the plan. The Board determined the initial offering period commenced on September 16, 2014 and the initial purchase occurred on the 6 month anniversary with subsequent 6 month purchase periods commencing on the day following the purchase from the prior period. The Company recorded $0.4 million , $0.4 million , and $0.3 million of stock-based compensation expense during the years ended December 31, 2019 , 2018 , and 2017 , respectively related to the 2013 ESPP. The number of shares available for future issuance was 122,589 at December 31, 2019 . In December 2016, the Company entered into a consulting agreement with its former Chief Executive Officer. In accordance with the 2003 Plan and 2013 Plan, any vested shares remain exercisable and any outstanding and unvested options and restricted stock units will continue to vest in accordance with their terms so long as he continues to provide services as a non-employee consultant. During the years ended December 31, 2019 , 2018 and 2017 , the Company recognized $1.0 million , $2.4 million , and $4.9 million , respectively, of stock-based compensation expense related to the agreement. The Company recognized stock-based compensation expense under the various Plans in the consolidated statements of operations and comprehensive loss as follows (in thousands): Year Ended December 31, 2019 2018 2017 Research and development $ 9,943 $ 12,669 $ 14,227 Selling, general and administrative 13,052 11,900 14,021 $ 22,995 $ 24,569 $ 28,248 The fair value of each option issued to employees was estimated on the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions: Year Ended December 31, 2019 2018 2017 Expected volatility 58.6 % 62.8 % 65.7 % Expected term (in years) 6.0 6.0 6.0 Risk-free interest rate 2.39 % 2.70 % 2.13 % Expected dividend yield — % — % — % The expected volatility of the options granted has been determined using a weighted-average of the historical volatility measures of a peer group of companies as well as the historical volatility of the Company's own common stock. As of September 2019, the Company had sufficient company-specific historical volatility data to begin estimating expected volatility by using it's own stock's data rather than a blended rate for most awards. The expected life of options has been determined utilizing the “simplified method”. The simplified method is based on the average of the vesting tranches and the contractual life of each grant. The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected life of the stock options. The Company has not paid, and does not anticipate paying, cash dividends on its common stock; therefore, the expected dividend yield is assumed to be zero . The Company accounts for forfeitures as they occur. Stock Option Activity The following table summarizes the stock option activity under the Company's stock option plans during the year ended December 31, 2019 (in thousands, except per share amounts and years): Number (in thousands) Weighted- Weighted- (in years) Aggregate Outstanding at December 31, 2018 3,513 $ 34.40 Granted 924 $ 42.32 Exercised (344 ) $ 29.33 Canceled or forfeited (273 ) $ 41.64 Outstanding at December 31, 2019 3,820 $ 36.26 6.81 $ 64,146 Exercisable at December 31, 2019 2,400 $ 33.76 5.80 $ 46,258 ______________________________________________________ (1) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for the options that were in the money at December 31, 2019 . During the years ended December 31, 2019 , 2018 and 2017 , the Company granted stock options to purchase an aggregate of 923,508 ; 942,271 ; and 701,384 shares of its common stock, respectively, with weighted-average grant date fair values of $23.65 , $25.05 , and $18.58 , respectively. During the years ended December 31, 2019 , 2018 and 2017 , current and former employees of the Company exercised a total of 344,257 ; 779,711 ; and 474,056 options, respectively, resulting in total proceeds of $10.1 million , $15.9 million , and $3.9 million , respectively. The aggregate intrinsic value of options exercised during the years ended December 31, 2019 , 2018 , and 2017 , under the Company's stock option plans, was $4.9 million , $19.3 million , and $10.2 million , respectively, calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for the options on the respective date of exercise. As of December 31, 2019 , there was $28.4 million of unrecognized compensation expense that is expected to be recognized over a weighted-average period of 2.4 years. Restricted Stock Units The following table summarizes the restricted stock unit (RSU) activity under the 2013 Plan during the year ended December 31, 2019 : Number of Weighted- Unvested balance at December 31, 2018 372 $ 36.53 Granted 216 $ 41.43 Vested (124 ) $ 34.59 Forfeited (67 ) $ 40.25 Unvested balance at December 31, 2019 397 $ 39.20 At December 31, 2019 , there was approximately $10.5 million of related unrecognized compensation cost which the Company expects to recognize over a remaining weighted-average period of 1.8 years. Performance-Based Restricted Stock Units The Company has granted performance-based restricted stock units (PSU) whereby vesting accelerates upon the occurrence of certain milestone events. In September 2019, all of the remaining unvested PSUs vested. The following table summarizes PSU activity under the 2013 Plan during the year ended December 31, 2019 : Number of Weighted- Unvested balance at December 31, 2018 236 $ 31.42 Granted — $ — Vested (227 ) $ 31.44 Forfeited (9 ) $ 31.09 Unvested balance at December 31, 2019 — $ — As of December 31, 2019 , all related compensation cost had been recognized. |
401(k) Savings Plan
401(k) Savings Plan | 12 Months Ended |
Dec. 31, 2019 | |
Retirement Benefits [Abstract] | |
401(k) Savings Plan | 401(k) Savings Plan In 2004, the Company established a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code (the 401(k) Plan). The 401(k) Plan covers all employees who meet defined minimum age and service requirements, and allows participants to defer a portion of their annual compensation on a pretax basis. For the years 2019 , 2018 , and 2017 , the Board approved matching contributions of up to $10,000 , $8,500 , and $7,000 , respectively, per eligible participant pursuant to the 401(k) Savings Plan’s matching formula. All matching contributions and participant contributions vest immediately. Matching contributions totaled $1.7 million , $1.1 million , and $0.7 million for the years ended December 31, 2019 , 2018 , and 2017 |
Income Taxes
Income Taxes | 12 Months Ended |
Dec. 31, 2019 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | Income Taxes The Company provides for income taxes under ASC 740. Under ASC 740, the liability method is used in accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and 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. U.S. Tax Reform On December 22, 2017, legislation commonly known as the Tax Cuts and Jobs Act (the Tax Act) was signed into law. The Tax Act, among other things, reduced the U.S. federal corporate tax rate from 35% to 21%, required taxpayers to pay a one-time transition tax on earnings of certain foreign subsidiaries that were previously tax deferred and created new taxes on certain foreign sourced earnings. The Company does not currently have any foreign subsidiaries and the international aspects of the Tax Act are not applicable as of December 31, 2019 . In connection with the Tax Act, as of December 31, 2017 , the Company remeasured certain deferred tax assets and liabilities based on the rates at which they are expected to reverse in the future, which is generally 21%. The remeasurement of the Company's deferred tax balance was primarily offset by application of its valuation allowance. Deferred tax assets and valuation allowance The Company recorded a tax benefit of $62,000 and $27,000 for the years ended December 31, 2019 and 2018 , respectively, related to the realization of current year losses that offset unrealized gains, recognized in other comprehensive income, from our investment portfolio. The Company recognized current income tax expense of $32,000 for the year ended December 31, 2017 related state income taxes on its interest income. The Company's loss before income taxes was $124.9 million , $118.9 million and $108.4 million for the years ended December 31, 2019 , 2018 and 2017 , respectively, and was generated entirely in the United States. Deferred taxes are recognized for temporary differences between the basis of assets and liabilities for financial statement and income tax purposes. The significant components of the Company's deferred tax assets are comprised of the following (in thousands): Year Ended December 31, 2019 2018 Deferred tax assets: U.S. and state net operating loss carryforwards $ 184,355 $ 149,170 Research and development credits 21,345 16,340 Stock compensation 14,024 13,819 Lease liabilities 7,090 — Accruals and other temporary differences 5,584 3,626 Total deferred tax assets 232,398 182,955 Right of use asset (6,429 ) — Less valuation allowance (225,969 ) (182,955 ) Net deferred tax assets $ — $ — The Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets. Based on the Company's history of operating losses, the Company has concluded that it is more likely than not that the benefit of its deferred tax assets will not be realized. Accordingly, the Company has provided a full valuation allowance for deferred tax assets as of December 31, 2019 and 2018 . The valuation allowance increased by $43.0 million , $37.3 million , and $9.1 million during the years ended December 31, 2019 , 2018 , and 2017 , respectively, due primarily to the generation of net operating losses during these periods, and the tax reform rate change during the year ended December 31, 2017 . A reconciliation of income tax expense computed at the statutory federal income tax rate to income taxes as reflected in the consolidated financial statements is as follows: Year Ended December 31, 2019 2018 2017 Federal income tax expense at statutory rate 21.0 % 21.0 % 34.0 % State income tax, net of federal benefit 9.9 % 7.0 % 5.6 % Permanent differences 0.2 % 2.0 % 1.9 % Research and development credit 4.2 % 3.2 % 1.9 % Tax reform rate change — % — % (54.7 )% Other (0.9 )% (0.6 )% (0.3 )% Change in valuation allowance (34.4 )% (32.6 )% 11.6 % Effective income tax rate — % — % — % As of December 31, 2019 and 2018 , the Company had U.S. federal net operating loss carryforwards of $666.3 million and $556.0 million , respectively, which may be available to offset future taxable income. Federal net operating loss carryforwards of $438.0 million will expire at various dates from 2023 through 2037. $228.3 million of the federal net operating loss carryforward can be carried forward indefinitely. As of December 31, 2019 and 2018 , the Company also had U.S. state net operating loss carryforwards of $689.8 million and $515.0 million , respectively, which may be available to offset future income tax liabilities. State net operating loss carryforwards of $689.4 million will expire at various dates from 2030 through 2039. State net operating loss carryforwards of $0.4 million can be carried forward indefinitely. As of December 31, 2019 and 2018 , the Company had federal research and development and orphan drug tax credit carryforwards of $14.5 million and $10.7 million , respectively, available to reduce future tax liabilities which expire at various dates through 2039 . As of December 31, 2019 and 2018 , the Company had state tax credit carryforwards of approximately $8.7 million and $7.1 million , respectively, available to reduce future tax liabilities which expire at various dates through 2034 . Under the provisions of the Internal Revenue Code, the net operating loss and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities. Net operating loss and tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three‑year period in excess of 50 percent, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions. This could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has completed several financings since its inception which may have resulted in a change in control as defined by Sections 382 and 383 of the Internal Revenue Code, or could result in a change in control in the future. The Company has completed an assessment through December 31, 2017 to determine whether there may have been a Section 382 ownership change and determined that it is more-likely-than-not that the Company’s net operating and tax credit amounts as disclosed are not subject to any material Section 382 limitations through December 31, 2017. If a change in ownership were to have occurred after that period, and resulted in the restriction of net operating loss and tax credit carryforwards, the reduction in the related deferred tax asset would be offset with a corresponding reduction in the valuation allowance. The Company will recognize interest and penalties related to uncertain tax positions in income tax expense. As of December 31, 2019 and 2018 , the Company had no accrued interest or penalties related to uncertain tax positions and no amounts have been recognized in the Company's consolidated statements of operations and comprehensive loss. For all years through December 31, 2019 , the Company generated research credits but has not conducted a study to document the qualified activities. This study may result in an adjustment to the Company’s research and development credit carryforwards; however, until a study is completed and any adjustment is known, no amounts are being presented as an uncertain tax position for the years ended December 31, 2019 and 2018 . A full valuation allowance has been provided against the Company’s research and development credits and, if an adjustment is required, this adjustment would be offset by an adjustment to the deferred tax asset established for the research and development credit carryforwards and the valuation allowance. The Company files income tax returns in the United States, and various state jurisdictions. The federal and state income tax returns are generally subject to tax examinations for the tax years ended December 31, 2016 through December 31, 2019 . To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service or state taxing authorities to the extent utilized in a future period. |
Leases
Leases | 12 Months Ended |
Dec. 31, 2019 | |
Leases [Abstract] | |
Leases | Leases Accounting under ASC 842 In February 2016, the FASB issued Accounting Standards Codification Topic 842, Leases (ASC 842 ), which replaces the existing guidance for leases. ASC 842 requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by all leases with terms of more than 12 months. ASC 842 also requires certain qualitative and quantitative disclosures designed to give financial statement users information on the amount, timing, and uncertainty of cash flows arising from leases. The Company adopted ASC 842 effective January 1, 2019. The Company elected to employ the transitionary relief offered by the FASB under ASU 2018-11 and implemented the new standard without the restatement of comparative periods' financial information. ASU-2018-11 also provides for recognizing the effects of applying ASC 842 as a cumulative-effect adjustment to retained earnings as of January 1, 2019; however, no such adjustment was recorded as of January 1, 2019. The Company elected to employ the package of practical expedients offered under ASC 842, which allowed the Company to not reassess the following: • the presence of a lease in any expired or existing contracts; • the lease classification for any existing or expired leases; and • the initial direct costs for any existing leases. The Company currently leases approximately 125,000 square feet of office and laboratory space in five adjacent buildings in Cambridge, Massachusetts (the Leases). The Leases were classified as operating leases under ASC 840. The Leases are also classified as operating leases under ASC 842 in accordance with the Company's election of the practical expedient under ASC 842. Pursuant to the package of practical expedients, the Company also did not reassess initial direct costs for the Leases. Additionally, the Company elected to account for the lease components and non-lease components as a single lease component. The Company occupied the premises of the Leases at various points in time prior to January 1, 2019 under non-cancelable agreements which expire at various dates through September 2023. Each of the Leases have options to renew for periods ranging from three to five years , which are not included in the measurement of these leases. All of the Company's leases contain escalating rent clauses, which require higher rent payments in future years. There are no variable payments, exercise purchase options, penalties, fees, or residual value guarantees under the Leases. The Company is also obligated to pay the Landlord for certain costs, taxes, and operating expenses related to the premises. However, the Company has concluded that these payments are not in-substance fixed payments and therefore are not included in the calculation of the related lease liability and asset under ASC 842. The Company recorded the liability associated with the Leases at the present value of the lease payments not yet paid, discounted using the discount rate for the Leases established at the adoption date. As the discount rate implicit in the Leases was typically not readily determinable, the Company utilized its incremental borrowing rate (IBR). In transition to ASC 842, the Company utilized the remaining lease term of its leases in determining the appropriate incremental borrowing rates. The IBR for the Leases was determined by establishing a credit rating of the Company using the Ordered Logit (oLogit) model. The oLogit Model is a quantitative method to assess the credit rating of a company. Based on the established credit rating, the Company determined a borrowing rate using regression analysis on selected financial ratios of publicly traded comparable companies and the companies' credit ratings, adjusted for the risk-free rate, which resulted in an IBR of approximately 10% . The Company recorded the liability associated with the Leases at the present value of the lease payments not yet paid, discounted using the incremental borrowing rate for each lease established at the adoption date. On January 1, 2019, the Company recorded a right-of-use asset in the amount of $29.1 million , which represented a lease liability of $31.0 million , adjusted for previously recognized lease-related balances, including deferred rent of $2.7 million and prepaid rent of $0.7 million . This lease liability will be reduced over the remaining lease term based on cash payments made offset by accretion of monthly interest calculated on the lease liability. The right-of-use asset will be amortized over the remaining lease term in an amount equal to the difference between the calculated straight-line expense of the total lease payments less the monthly interest calculated on the remaining lease liability. The adoption of ASC 842 did not have a material impact on the consolidated statement of operations and comprehensive loss for the year ended December 31, 2019 , or the consolidated statement of cash flows for the year ended December 31, 2019 . Future minimum lease payments under the Company's non-cancelable operating leases as of December 31, 2019 , are as follows (in thousands): As of December 31, 2019 2020 $ 8,610 2021 8,336 2022 8,409 2023 6,450 Total lease payments $ 31,805 Less: imputed interest (5,421 ) Total operating lease liabilities $ 26,384 The Company recognizes rent expense, calculated as the remaining cost of the lease allocated over the remaining lease term on a straight-line basis. Rent expense is presented as a part of continuing operations in the consolidated statement of operations and comprehensive loss. For the year ended December 31, 2019 , the Company recognized rent expense of $8.2 million . For the year ended December 31, 2019 , the Company paid $8.4 million in rent relating to the Leases. As payments resulting from an operating lease, the $8.4 million is classified within operating activities in the consolidated statements of cash flows. The following table contains supplemental balance sheet information pertaining to the Company's leases as of December 31, 2019 : As of December 31, 2019 Weighted average remaining lease term 3.7 years Weighted average discount rate 10.59 % Accounting under ASC 840 Prior to the adoption of ASC 842, the Company recorded rent expense on a straight-line basis over the term of the lease, including any rent-free periods. In addition, the Company recorded deferred rent for certain lease incentives received, which were amortized as a reduction of rent expense over the life of the lease. Rent expense was presented as part of continuing operations in the consolidated statement of operations and comprehensive loss; deferred rent was recorded on the consolidated balance sheet. As of December 31, 2018 , the future minimum lease payments due were as follows (in thousands): As of December 31, 2018 2019 $ 8,195 2020 8,438 2021 8,180 2022 8,256 2023 6,333 Total future lease payments $ 39,402 The Company recorded total rent expense of $ 5.8 million and $ 4.8 million |
Related Party Transactions
Related Party Transactions | 12 Months Ended |
Dec. 31, 2019 | |
Related Party Transactions [Abstract] | |
Related Party Transactions | Related Party Transactions Celgene (BMS) In connection with the Company's January 2019, September 2017 and January 2016 public offerings, BMS purchased 706,206 , 745,592 and 800,000 shares of common stock, respectively. In connection with these and prior transactions, BMS owned 12.0% and 12.2% of the Company's fully diluted equity as of December 31, 2019 and 2018 , respectively. During the years ended December 31, 2019 , 2018 and 2017 , all revenue recognized by the Company was recognized under the BMS collaboration agreement. Refer to Note 10 for additional information regarding these collaboration agreements. |
Quarterly Financial Data (unaud
Quarterly Financial Data (unaudited) | 12 Months Ended |
Dec. 31, 2019 | |
Quarterly Financial Information Disclosure [Abstract] | |
Quarterly Financial Data (unaudited) | Quarterly Financial Data (unaudited) The following table presents certain unaudited quarterly financial information for the previous eight quarters. This information has been prepared on the same basis as the audited financial statements and includes all adjustments (consisting only of normal recurring adjustments) necessary to present fairly the unaudited quarterly results of operations set forth herein. For the Three Months Ended(1) March 31 June 30 September 30 December 31 (in thousands except per share data) 2019 Total revenue $ 2,780 $ 27,666 $ 4,208 $ 39,338 Total costs and expenses 43,585 48,802 53,131 64,919 Loss from operations (40,805 ) (21,136 ) (48,923 ) (25,581 ) Net loss (38,053 ) (17,862 ) (45,369 ) (23,575 ) Net loss per share- basic and diluted $ (0.74 ) $ (0.34 ) $ (0.86 ) $ (0.44 ) 2018 Total revenue $ 3,232 $ 3,685 $ 3,258 $ 3,816 Total costs and expenses 30,872 33,591 33,320 40,622 Loss from operations (27,640 ) (29,906 ) (30,062 ) (36,806 ) Net income (loss) (26,219 ) (28,938 ) (28,979 ) (34,734 ) Net loss per share- basic and diluted $ (0.58 ) $ (0.63 ) $ (0.63 ) $ (0.75 ) ______________________________________________________ (1) |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
Dec. 31, 2019 | |
Accounting Policies [Abstract] | |
Principles of Consolidation | Principles of Consolidation The accompanying consolidated financial statements include those of the Company and its wholly-owned subsidiary, Acceleron Securities Corp. All significant intercompany balances and transactions have been eliminated in consolidation. |
Basis of Presentation | Basis of Presentation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB). |
Use of Estimates | Use of Estimates The preparation of financial statements in conformity with GAAP requires management 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 expensed during the reporting period. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these consolidated financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes and management must select an amount that falls within that range of reasonable estimates. This process may result in actual results differing materially from those estimated amounts used in the preparation of the consolidated financial statements if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. In preparing these consolidated financial statements, management used estimates in the following areas, among others: accrued and prepaid clinical expenses, stock-based compensation expense, revenue recognition and the recoverability of the Company's net deferred tax assets and related valuation allowance. |
Collaboration Receivable | Collaboration Receivable Credit is extended to customers based upon an evaluation of the customer's financial condition. Collaboration receivables are recorded at net realizable value. The Company does not charge interest on past due balances. Collaboration receivables are determined to be past due when the payment due date is exceeded. The Company utilizes a specific identification accounts |
Segment Information | Segment Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision making group, in making decisions on how to allocate resources and assess performance. The Company's chief operating decision maker is the chief executive officer. The Company and the chief executive officer view the Company's operations and manage its business as one operating segment, which is the discovery, development and commercialization of highly innovative therapeutics to treat serious and rare diseases. All material long-lived assets of the Company reside in the United States. The Company does use contract research organizations (CROs) and research institutions located outside the United States. Some of these expenses are subject to collaboration reimbursement which is presented as a component of cost-sharing, net in the consolidated statements of operations and comprehensive loss. |
Cash, Cash Equivalents | Cash, Cash Equivalents and Short-term and Long-term Investments The Company considers all highly liquid investments purchased with original maturities of 90 days or less at the date of acquisition to be cash equivalents. Cash and cash equivalents include cash held in banks and amounts held in interest-bearing money market accounts, as well as marketable securities with a remaining maturity of 90 days or less. Cash equivalents are carried at cost, which approximates their fair market value. |
Short-term and Long-term Investments | The Company determines the appropriate classification of marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. The Company has classified all of its marketable securities at December 31, 2019 and 2018 as “available-for-sale” pursuant to ASC 320, Investments – Debt and Equity Securities. The Company records available-for-sale securities at fair value, with the unrealized gains and losses included in accumulated other comprehensive income (loss) in stockholders’ equity. There were no realized gains or losses on marketable securities for the years ended December 31, 2019 , 2018 and 2017 . Investments not classified as cash equivalents are presented as either short-term or long-term investments based on both their maturities as well as the time period the Company intends to hold such securities. The Company adjusts the cost of available-for-sale debt securities for amortization of premiums and accretion of discounts to maturity. The Company includes such amortization and accretion in interest income. The cost of securities sold is based on the specific identification method. The Company includes interest and dividends on securities classified as available-for-sale in interest income in the accompanying consolidated statements of operations and comprehensive loss. The Company reviews marketable securities for other-than-temporary impairment whenever the fair value of a marketable security is less than the amortized cost and evidence indicates that a marketable security’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the marketable security, or if it is more likely than not that the Company will be required to sell the marketable security before recovery of the amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, compliance with the Company’s investment policy, the severity and the duration of the impairment and changes in value subsequent to the end of the period. The aggregate fair value of securities held by the Company in an unrealized loss position for less than twelve months as of December 31, 2019 and December 31, 2018 was $35.8 million and $51.2 million , respectively. The aggregate fair value of securities held by the Company in an unrealized loss position for more than twelve months as of December 31, 2019 and December 31, 2018 was zero and $94.3 million , respectively. The aggregate unrealized loss for those securities in an unrealized loss position for more than twelve months was zero and $0.4 million |
Concentrations of Credit Risk and Off-Balance Sheet Risk | Concentrations of Credit Risk and Off-Balance Sheet Risk The Company has no off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments that potentially subject the Company to concentrations of credit risk are primarily cash, cash equivalents, restricted cash, short-term and long-term investments and collaboration receivables. The Company maintains its cash and cash equivalent balances and short-term and long-term investments with financial institutions that management believes are creditworthy. Short-term and long-term investments consist of investment grade corporate obligations, treasury notes, asset backed securities, and certificates of deposit. The Company's investment policy includes guidelines on the quality of the institutions and financial instruments and defines allowable investments that the Company believes minimizes the exposure to concentrations of credit risk. The Company routinely assesses the creditworthiness of its customers and collaboration partners. The Company has not experienced any material losses related to receivables from individual customers and collaboration partners, or groups of customers. The Company does not require collateral. Due to these factors, no additional credit risk beyond amounts provided for collection losses is believed by management to be probable in the Company's collaboration receivables. |
Disclosure of Fair Value of Financial Instruments | Disclosure of Fair Value of Financial Instruments The Company's financial instruments include cash, cash equivalents, short-term and long-term investments, collaboration receivables, common stock warrants, accounts payable, and accrued expenses. See discussion below on the determination of the fair value of the Company's common stock warrants and short-term and long-term investments. The carrying value of the remainder of the Company's financial instruments approximated their fair values at December 31, 2019 and 2018 due to the short-term nature of these instruments. The Company has evaluated the estimated fair value of financial instruments using available market information and management's estimates. The use of different market assumptions and/or estimation methodologies could have a significant effect on the estimated fair value amounts. |
Fair Value Measurements | Fair Value Measurements ASC Topic 820, Fair Value Measurement (ASC 820), establishes a fair value hierarchy for instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company's own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company's assumptions about the inputs that market participants would use in pricing the asset or liability, and are developed based on the best information available in the circumstances. ASC 820 identifies fair value as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a three-tier fair value hierarchy that distinguishes between the following: • Level 1—Quoted market prices in active markets for identical assets or liabilities. • Level 2—Inputs other than Level 1 inputs that are either directly or indirectly observable, such as quoted market prices, interest rates, and yield curves. • Level 3—Unobservable inputs developed using estimates of assumptions developed by the Company, which reflect those that a market participant would use. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument's level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Items measured at fair value on a recurring basis include short-term and long-term investments (Note 5), and warrants to purchase common stock (Note 7). During the periods presented, the Company has not changed the manner in which it values assets and liabilities that are measured at fair value using Level 3 inputs. The following tables set forth the Company's financial instruments carried at fair value using the lowest level of input applicable to each financial instrument as of December 31, 2019 and 2018 (in thousands): December 31, 2019 Quoted Prices Significant Other Significant Total Assets: Money market funds $ 193,867 $ — $ — $ 193,867 Corporate obligations — 138,369 — 138,369 U.S. Treasury securities — 83,819 — 83,819 Certificates of deposit — 493 — 493 Mortgage and other asset backed securities — 12,470 — 12,470 Total assets $ 193,867 $ 235,151 $ — $ 429,018 Liabilities: Warrants to purchase common stock $ — $ — $ 1,856 $ 1,856 Total liabilities $ — $ — $ 1,856 $ 1,856 December 31, 2018 Quoted Prices Significant Other Significant Total Assets: Money market funds $ 74,023 $ — $ — $ 74,023 Corporate obligations — 128,920 — 128,920 U.S. Treasury securities — 56,978 — 56,978 Certificates of deposit — 1,715 — 1,715 Mortgage and other asset backed securities — 26,874 — 26,874 Total assets $ 74,023 $ 214,487 $ — $ 288,510 Liabilities: Warrants to purchase common stock $ — $ — $ 1,491 $ 1,491 Total liabilities $ — $ — $ 1,491 $ 1,491 The money market funds noted above are included in cash and cash equivalents in the accompanying consolidated balance sheets. The Company recognizes transfers between levels of the fair value hierarchy as of the end of the reporting period. There were no transfers within the hierarchy during the years ended December 31, 2019 and 2018 . The following table sets forth a summary of changes in the fair value of the Company's common stock warrant liabilities, which represent a recurring measurement that is classified within Level 3 of the fair value hierarchy, wherein fair value is estimated using significant unobservable inputs (in thousands): Year Ended December 31, 2019 2018 Beginning balance $ 1,491 $ 2,236 Change in fair value 365 52 Exercises — (797 ) Ending balance $ 1,856 $ 1,491 The fair value of the warrants to purchase common stock on the date of issuance and on each re-measurement date for those warrants classified as liabilities was estimated using either the Monte Carlo simulation framework, which incorporates future financing events over the remaining life of the warrants to purchase common stock, or for certain re-measurement dates, due to the warrants being deeply in the money, the Black-Scholes option pricing model. The Black-Scholes method of valuation involves using inputs such as the fair value of the Company's stock, stock price volatility, the contractual term of the warrants, risk-free interest rates, and dividend yields. At each reporting period the Company evaluates the best valuation methodology. At December 31, 2019 , and December 31, 2018 and December 31, 2017 , the Black-Scholes option pricing model was used. Due to the nature of these inputs, the valuation of the warrants is considered a Level 3 measurement. See Note 7 for further discussions of the accounting for the warrants. The Company measures eligible assets and liabilities at fair value, with changes in value recognized in earnings. Fair value treatment may be elected either upon initial recognition of an eligible asset or liability or, for an existing asset or liability, if an event triggers a new basis of accounting. The Company did not elect to remeasure any of its existing financial assets or liabilities, and did not elect the fair value option for any financial assets and liabilities transacted in the years ended December 31, 2019 or 2018 . |
Property and Equipment | Property and Equipment Property and equipment is stated at cost. Maintenance and repairs that do not improve or extend the lives of the respective assets are expensed to operations as incurred. Upon disposal, retirement or sale the related cost and accumulated depreciation is removed from the accounts and any resulting gain or loss is included in the results of operations. Depreciation and amortization is calculated using the straight-line method over the estimated useful lives of the assets, which are as follows: Asset Estimated Useful Life Computer equipment and software 3 years Office and laboratory equipment 3 years Leasehold improvements Shorter of the useful life or remaining lease term |
Revenue Recognition | Revenue Recognition Effective January 1, 2018, the Company adopted Accounting Standards Codification Topic 606, Revenue from Contracts with Customers , (ASC 606), using the modified retrospective transition method. Under this method, results for reporting periods beginning January 1, 2018 are presented under ASC 606, while prior period amounts are not adjusted and continue to be reported in accordance with ASC 605. The Company has primarily generated revenue through collaboration, license and research arrangements, which are within the scope of ASC 606, with collaboration partners for the development and commercialization of therapeutic candidates. The arrangements generally contain performance obligations, which may include (1) licenses, or options to obtain licenses, to the Company's technology, (2) research and development activities performed for the collaboration partners (3) participation on joint development committees (JDCs), and (4) the manufacturing of clinical or preclinical material. Payments pursuant to these arrangements typically include non-refundable, upfront payments, milestone payments upon achieving significant development events, research and development reimbursements, sales milestones, exercises of options, and royalties on future product sales. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company's consolidated balance sheets. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, current portion. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, net of current portion. Amounts recognized as revenue, but not yet received or invoiced are generally recognized as contract assets, including collaboration receivables. To determine revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with the customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract, determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. Depending on the nature of the performance obligation these assessments require management to make judgments and estimates. Exclusive Licenses If the license to the Company’s intellectual property is determined to be distinct from the other promises or performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, upfront fees allocated to the license when the license is transferred and the customer is able to use and benefit from the license. In order to assess whether the license is distinct, the Company considers the capabilities of the collaboration partner and the availability of the necessary expertise in the general marketplace to determine whether the collaboration partner can benefit from the license for its intended purpose without the receipt of the remaining elements. For licenses determined not to be distinct the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. The measure of progress, and thereby periods over which revenue should be recognized, are subject to estimates by management and may change over the course of the research and development and licensing agreement. Research and Development Services The promises under the Company’s collaboration and license agreements generally include research and development services to be performed by the Company on behalf of the collaboration partner. As the provision of research and development services is a part of the Company’s central operations, when the Company is principally responsible for the performance of these services under the agreements, the Company recognizes revenue on a gross basis for research and development services in accordance with the ASC 606 framework described above. Customer Options The Company's agreements may contain options which provide the collaboration partner the right to obtain additional licenses. If an arrangement is determined to contain customer options, the goods and services underlying the customer options are not considered to be performance obligations at the inception of the arrangement, and the associated option fees are not included in the transaction price. The Company evaluates the customer options to determine if they represent material rights, which may include options to acquire additional goods or services for free or at a discount. If the customer options are determined to represent a material right, the material right is recognized as a separate performance obligation at the outset of the arrangement. The Company allocates the transaction price to material rights based on the relative standalone selling price, which is determined based on the identified discount and the probability that the customer will exercise the option. Amounts allocated to a material right are not recognized as revenue until, at the earliest, the option is exercised. Milestone Payments At the inception of each arrangement that includes milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. The Company evaluates factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the respective milestone in making this assessment. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. If a milestone or other variable consideration relates specifically to the Company's efforts to satisfy a single performance obligation or to a specific outcome from satisfying the performance obligation, the Company generally allocates the milestone amount entirely to that performance obligation. Royalties For arrangements that include sales-based royalties, including milestone payments based on a level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has recognized minimal royalty revenue resulting from any of its licensing arrangements. |
Accrued and Prepaid Clinical Trail Expenses/Research and Development Expenses | Research and Development Expenses Research and development costs are charged to expense as costs are incurred in performing research and development activities. Research and development costs include all direct costs, including salaries, stock compensation and benefits for research and development personnel, outside consultants, costs of clinical trials, costs related to acquiring and manufacturing clinical study materials, sponsored research, clinical trials insurance, other outside costs, depreciation and facility costs related to the development of drug candidates. The Company records upfront, non-refundable payments made to outside vendors, or other payments made in advance of services performed or goods being delivered, as prepaid expenses, which are expensed as services are performed or the goods are delivered. Certain research and development projects are, or have been, partially funded by collaboration agreements, and the expenses related to these activities are included in research and development costs. The Company records the related reimbursement of research and development costs under these agreements as revenue, as more fully described above and in Note 10. Accrued and Prepaid Clinical Trial Expenses The Company accrues for estimated costs of research and development activities conducted by third-party service providers, which includes the conduct of clinical trials. The Company records the estimated costs of clinical trial activities based upon the estimated amount of services provided and includes the costs incurred but not yet invoiced within accrued liabilities on the balance sheet and within research and development expense in the consolidated statements of operations and comprehensive loss. Invoicing from third-party service providers may not coincide with actual work performed and can result in the Company being in a prepaid position at period end. These costs can be a significant component of the Company's research and development expenses. The Company estimates the amount of services provided and efforts expended pursuant to quotes and contracts with third parties, as well as discussion with internal personnel and external service providers as to the progress of the services and the agreed-upon fee to be paid for such services. The Company makes significant judgments and estimates in determining the services incurred as of the balance sheet date, which may result in either an accrual or prepaid balance. As actual costs become known, it adjusts its estimates. Although the Company does not expect its estimates to be materially different from amounts actually incurred, its understanding of the status and timing of services performed, the number of subjects enrolled, and the rate of enrollment may vary from its estimates and could result in the Company reporting amounts that are too high or too low in a particular period. The Company's accrued and prepaid expenses are dependent, in part, upon the receipt of timely and accurate reporting from contract research organizations and third-party service providers. To date, the Company has not experienced any material differences between its estimated costs and actual costs incurred. |
Stock-Based Compensation | Stock-Based Compensation At December 31, 2019 , the Company had two stock-based compensation plans, which are more fully described in Note 11. The Company accounts for stock-based compensation in accordance with the provisions of ASC Topic 718, Compensation—Stock Compensation (ASC 718), which requires the recognition of expense related to the fair value of stock-based compensation awards in the consolidated statements of operations and comprehensive loss. For stock-based awards issued to employees and members of the Company's board of directors (the Board) for their services on the Board and for participation in the employee stock purchase plan, the Company estimates the grant date fair value of each option award using the Black-Scholes option pricing model. The use of the Black-Scholes option pricing model requires management to make assumptions with respect to the expected term of the option, the expected volatility of the common stock consistent with the expected life of the option, risk-free interest rates and expected dividend yields of the common stock. For awards subject to service-based vesting conditions, the Company recognizes stock-based compensation expense, equal to the grant date fair value of stock options on a straight-line basis over the requisite service period, which is generally the vesting term. For awards subject to both performance and service-based vesting conditions, the Company recognizes stock-based compensation expense using an accelerated recognition method when it is probable that the performance condition will be achieved. If achievement of the performance condition is not probable, but the award will vest based on the service condition, expense is recognized over the requisite service period. |
Income Taxes | Income Taxes Income taxes are recorded in accordance with ASC Topic 740, Income Taxes (ASC 740), which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are provided, if based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. |
Net Loss Per Share | Net Loss Per Share The Company calculates basic and diluted net loss per common share by dividing the net loss by the weighted-average number of common shares outstanding during the period. For the years ended December 31, 2019 , 2018 and 2017 , the Company has excluded the effects of all potentially dilutive shares, which include outstanding common stock options, warrants to purchase common stock, common stock issuable under the employee stock purchase plan, and restricted stock units, from the weighted-average number of common shares outstanding as their inclusion in the computation for these years would be anti-dilutive due to net losses incurred. |
Comprehensive Income (Loss) | Comprehensive Income (Loss) Comprehensive Income (loss) is defined as the change in equity of a business enterprise during a period from transactions, other events, and circumstances from non-owner sources. Comprehensive income (loss) consists of net loss and other comprehensive income (loss), which includes certain changes in equity that are excluded from net loss. Comprehensive income (loss) has been disclosed in the accompanying consolidated statements of operations and comprehensive loss. Accumulated other comprehensive loss is presented separately on the consolidated balance sheets and consists entirely of unrealized holdings gains or losses on investments as of December 31, 2019 and 2018 . |
Subsequent Events | Subsequent Events The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated as required. The Company has evaluated all subsequent events and determined that there are no material recognized or unrecognized subsequent events requiring disclosure. |
Recently Adopted and Recent Accounting Pronouncements - Not Yet Adopted | Recently Adopted Accounting Pronouncements In February 2016, FASB, issued ASU 2016-02, Leases (Topic 842), Amendments to the FASB Accounting Standards Codification . ASU 2016-02 requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by leases. On January 1, 2019, the Company adopted ASU 2016-02 and all related amendments. For discussion regarding the impact of this accounting pronouncement, refer to Note 14 within the notes to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K. In March 2017, the FASB issued Accounting Standards Update 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities (ASU 2017-08). This standard amends the amortization period for certain purchased callable debt securities held at a premium by shortening the amortization period to the earliest call date. On January 1, 2019, the Company adopted ASU 2017-08, with no material impact on its consolidated financial statements and related disclosures. Recent Accounting Pronouncements - Not Yet Adopted From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its financial position or results of operations upon adoption. In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses . The new standard requires entities to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. For available-for-sale debt securities with unrealized losses, the standard requires allowances to be recorded instead of reducing the amortized cost of the investment. The standard limits the amount of credit losses to be recognized for available-for-sale debt securities to the amount by which the carrying value exceeds fair value and requires the reversal of previously recognized credit losses if fair value increases. ASU 2016-13 will become effective for the Company beginning on January 1, 2020. The Company is currently evaluating the impact ASU 2016-13 will have on its consolidated financial statements and related disclosures. In June 2018, the FASB issued ASU 2018-15, Intangible-Goodwill and Other Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract . This amendment aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The standard will become effective for the Company beginning on January 1, 2020. The Company does not anticipate that ASU 2018-15 will have a material impact on its consolidated financial statements and related disclosures. In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes . The ASU simplifies the accounting for income taxes by eliminating certain exceptions to the guidance in ASC 740, Income Taxes , related to the approach for allocating income tax expense or benefit for the year to continuing operations, discontinued operations, other comprehensive income, and other charges or credits recorded directly to shareholders’ equity; the methodology for calculating income taxes in an interim period; and the recognition of deferred tax liabilities for outside basis differences. The ASU will become effective for the Company beginning on January 1, 2021, with early adoption permitted. The Company is currently assessing the timing of adoption as well as the impact of adoption on its consolidated financial statements and related disclosures. |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Accounting Policies [Abstract] | |
Schedule of Financial Instruments Carried at Fair Value | The following tables set forth the Company's financial instruments carried at fair value using the lowest level of input applicable to each financial instrument as of December 31, 2019 and 2018 (in thousands): December 31, 2019 Quoted Prices Significant Other Significant Total Assets: Money market funds $ 193,867 $ — $ — $ 193,867 Corporate obligations — 138,369 — 138,369 U.S. Treasury securities — 83,819 — 83,819 Certificates of deposit — 493 — 493 Mortgage and other asset backed securities — 12,470 — 12,470 Total assets $ 193,867 $ 235,151 $ — $ 429,018 Liabilities: Warrants to purchase common stock $ — $ — $ 1,856 $ 1,856 Total liabilities $ — $ — $ 1,856 $ 1,856 December 31, 2018 Quoted Prices Significant Other Significant Total Assets: Money market funds $ 74,023 $ — $ — $ 74,023 Corporate obligations — 128,920 — 128,920 U.S. Treasury securities — 56,978 — 56,978 Certificates of deposit — 1,715 — 1,715 Mortgage and other asset backed securities — 26,874 — 26,874 Total assets $ 74,023 $ 214,487 $ — $ 288,510 Liabilities: Warrants to purchase common stock $ — $ — $ 1,491 $ 1,491 Total liabilities $ — $ — $ 1,491 $ 1,491 |
Summary of Changes in the Fair Value of Preferred and Common Stock Warrants | The following table sets forth a summary of changes in the fair value of the Company's common stock warrant liabilities, which represent a recurring measurement that is classified within Level 3 of the fair value hierarchy, wherein fair value is estimated using significant unobservable inputs (in thousands): Year Ended December 31, 2019 2018 Beginning balance $ 1,491 $ 2,236 Change in fair value 365 52 Exercises — (797 ) Ending balance $ 1,856 $ 1,491 |
Schedule of Estimated Useful Lives of Property and Equipment | Depreciation and amortization is calculated using the straight-line method over the estimated useful lives of the assets, which are as follows: Asset Estimated Useful Life Computer equipment and software 3 years Office and laboratory equipment 3 years Leasehold improvements Shorter of the useful life or remaining lease term |
Schedule of Anti-dilutive Common Stock Equivalents Excluded from the Calculation of Diluted Net Income (Loss) per Share | The following is a summary of the common stock equivalents which were excluded from the calculation of diluted net loss per share for the periods indicated (in thousands): Year Ended December 31, 2019 2018 2017 Outstanding stock options 3,820 3,513 3,452 Common stock warrants 39 39 61 Shares issuable under employee stock purchase plan 23 18 18 Restricted stock units 397 608 604 Total excluded common stock equivalents 4,279 4,178 4,135 |
Property and Equipment, Net (Ta
Property and Equipment, Net (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Property, Plant and Equipment [Abstract] | |
Schedule of Property and Equipment, Net | Property and equipment, net, consists of the following (in thousands): December 31, 2019 2018 Computer equipment and software $ 1,767 $ 1,712 Office equipment 672 672 Laboratory equipment 22,079 19,948 Leasehold improvements 12,347 11,668 Construction in progress 1,181 1,139 Total property and equipment 38,046 35,139 Accumulated depreciation and amortization (31,234 ) (28,033 ) Property and equipment, net $ 6,812 $ 7,106 |
Restricted Cash (Tables)
Restricted Cash (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Cash and Cash Equivalents [Abstract] | |
Schedule of Cash and Cash Equivalents | The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheet that sum to the total of the same such amounts shown in the statement of cash flows (in thousands): December 31, 2019 2018 2017 Cash and cash equivalents $ 237,677 $ 144,052 $ 100,150 Restricted cash 1,597 1,597 1,132 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 239,274 $ 145,649 $ 101,282 |
Restrictions on Cash and Cash Equivalents | The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheet that sum to the total of the same such amounts shown in the statement of cash flows (in thousands): December 31, 2019 2018 2017 Cash and cash equivalents $ 237,677 $ 144,052 $ 100,150 Restricted cash 1,597 1,597 1,132 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 239,274 $ 145,649 $ 101,282 |
Cash, Cash Equivalents and Sh_2
Cash, Cash Equivalents and Short-term and Long-term Investments (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Cash and Cash Equivalents [Abstract] | |
Schedule of Available-for-Sale Securities | The following is a summary of cash, cash equivalents and available-for-sale securities as of December 31, 2019 and December 31, 2018 (in thousands): December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Cash and cash equivalents due in 90 days or less $ 237,677 $ — $ — $ 237,677 Available-for-sale securities: Corporate obligations 124,676 219 (15 ) 124,880 U.S. Treasury securities 78,230 98 (1 ) 78,327 Certificates of deposit 490 3 — 493 Mortgage and other asset backed securities 12,476 5 (12 ) 12,469 Total available-for-sale securities $ 215,872 $ 325 $ (28 ) $ 216,169 Total cash, cash equivalents and available-for-sale securities $ 453,549 $ 325 $ (28 ) $ 453,846 December 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Cash and cash equivalents due in 90 days or less $ 144,064 $ — $ (12 ) $ 144,052 Available-for-sale securities: Corporate obligations due in one year or less 73,671 — (267 ) 73,404 U.S. Treasury securities due in one year or less 45,346 — (79 ) 45,267 Certificates of deposit due in one year or less 1,715 — — 1,715 Mortgage and other asset backed securities due in one year or less 26,982 — (108 ) 26,874 Total available-for-sale securities $ 147,714 $ — $ (454 ) $ 147,260 Total cash, cash equivalents and available-for-sale securities $ 291,778 $ — $ (466 ) $ 291,312 |
Accrued Expenses (Tables)
Accrued Expenses (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Payables and Accruals [Abstract] | |
Schedule of Accrued Expenses | Accrued expenses consist of the following (in thousands): December 31, 2019 2018 Research and development $ 11,844 $ 8,144 Commercial 1,027 — Employee compensation 9,932 7,975 Professional services 976 621 Accrued purchases 119 351 Other 997 1,118 Total accrued expenses $ 24,895 $ 18,209 |
Warrants (Tables)
Warrants (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Warrants and Rights Note Disclosure [Abstract] | |
Summary of Shares Issuable Upon Exercise of Outstanding Warrants | Below is a summary of the number of shares issuable upon exercise of outstanding warrants and the terms and accounting treatment for the outstanding warrants (in thousands, except per share data): Warrants as of Weighted- Average Exercise Balance Sheet Classification December 31, 2019 December 31, 2018 Price Per Share Expiration December 31, 2019 December 31, 2018 Warrants to purchase common stock 39 39 $ 5.88 June 10, 2020 - July 9, 2020 Liability Liability All warrants 39 39 $ 5.88 ______________________________________________________________________ |
Stockholders' Equity (Tables)
Stockholders' Equity (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Stockholders' Equity Note [Abstract] | |
Schedule of Common Stock Reserved for Future Issuance | At December 31, 2019 , the Company has reserved for future issuance the following number of shares of common stock (in thousands): December 31, 2019 Outstanding stock options to purchase common stock 3,820 Outstanding restricted stock units 397 Shares available for future issuance under equity incentive plan 4,634 Warrants to purchase common stock 39 Shares available for future issuance under the employee stock purchase plan 123 Additional shares reserved for unissued, but designated, Preferred Stock 25,000 Total shares of authorized common stock reserved for future issuance 34,013 |
Stock-Based Compensation (Table
Stock-Based Compensation (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Share-based Payment Arrangement [Abstract] | |
Schedule of Total Compensation Cost Recognized for all Stock-based Awards | The Company recognized stock-based compensation expense under the various Plans in the consolidated statements of operations and comprehensive loss as follows (in thousands): Year Ended December 31, 2019 2018 2017 Research and development $ 9,943 $ 12,669 $ 14,227 Selling, general and administrative 13,052 11,900 14,021 $ 22,995 $ 24,569 $ 28,248 |
Schedule of Stock Option Valuation Assumptions | The fair value of each option issued to employees was estimated on the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions: Year Ended December 31, 2019 2018 2017 Expected volatility 58.6 % 62.8 % 65.7 % Expected term (in years) 6.0 6.0 6.0 Risk-free interest rate 2.39 % 2.70 % 2.13 % Expected dividend yield — % — % — % |
Summary of Stock Option Activity | The following table summarizes the stock option activity under the Company's stock option plans during the year ended December 31, 2019 (in thousands, except per share amounts and years): Number (in thousands) Weighted- Weighted- (in years) Aggregate Outstanding at December 31, 2018 3,513 $ 34.40 Granted 924 $ 42.32 Exercised (344 ) $ 29.33 Canceled or forfeited (273 ) $ 41.64 Outstanding at December 31, 2019 3,820 $ 36.26 6.81 $ 64,146 Exercisable at December 31, 2019 2,400 $ 33.76 5.80 $ 46,258 ______________________________________________________ (1) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for the options that were in the money at December 31, 2019 . |
Schedule of Restricted Stock Unit Activity | The following table summarizes the restricted stock unit (RSU) activity under the 2013 Plan during the year ended December 31, 2019 : Number of Weighted- Unvested balance at December 31, 2018 372 $ 36.53 Granted 216 $ 41.43 Vested (124 ) $ 34.59 Forfeited (67 ) $ 40.25 Unvested balance at December 31, 2019 397 $ 39.20 |
Performance Shares Units Nonvested Activity | The following table summarizes PSU activity under the 2013 Plan during the year ended December 31, 2019 : Number of Weighted- Unvested balance at December 31, 2018 236 $ 31.42 Granted — $ — Vested (227 ) $ 31.44 Forfeited (9 ) $ 31.09 Unvested balance at December 31, 2019 — $ — |
Income Taxes (Tables)
Income Taxes (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Income Tax Disclosure [Abstract] | |
Components of the Company's Deferred Tax Assets | The significant components of the Company's deferred tax assets are comprised of the following (in thousands): Year Ended December 31, 2019 2018 Deferred tax assets: U.S. and state net operating loss carryforwards $ 184,355 $ 149,170 Research and development credits 21,345 16,340 Stock compensation 14,024 13,819 Lease liabilities 7,090 — Accruals and other temporary differences 5,584 3,626 Total deferred tax assets 232,398 182,955 Right of use asset (6,429 ) — Less valuation allowance (225,969 ) (182,955 ) Net deferred tax assets $ — $ — |
Schedule of Effective Income Tax Rate Reconciliation | A reconciliation of income tax expense computed at the statutory federal income tax rate to income taxes as reflected in the consolidated financial statements is as follows: Year Ended December 31, 2019 2018 2017 Federal income tax expense at statutory rate 21.0 % 21.0 % 34.0 % State income tax, net of federal benefit 9.9 % 7.0 % 5.6 % Permanent differences 0.2 % 2.0 % 1.9 % Research and development credit 4.2 % 3.2 % 1.9 % Tax reform rate change — % — % (54.7 )% Other (0.9 )% (0.6 )% (0.3 )% Change in valuation allowance (34.4 )% (32.6 )% 11.6 % Effective income tax rate — % — % — % |
Leases (Tables)
Leases (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Leases [Abstract] | |
Lessee, operating lease, liability, maturity | Future minimum lease payments under the Company's non-cancelable operating leases as of December 31, 2019 , are as follows (in thousands): As of December 31, 2019 2020 $ 8,610 2021 8,336 2022 8,409 2023 6,450 Total lease payments $ 31,805 Less: imputed interest (5,421 ) Total operating lease liabilities $ 26,384 |
Lease, cost | The following table contains supplemental balance sheet information pertaining to the Company's leases as of December 31, 2019 : As of December 31, 2019 Weighted average remaining lease term 3.7 years Weighted average discount rate 10.59 % |
Schedule of future minimum rental payments for operating leases | As of December 31, 2018 , the future minimum lease payments due were as follows (in thousands): As of December 31, 2018 2019 $ 8,195 2020 8,438 2021 8,180 2022 8,256 2023 6,333 Total future lease payments $ 39,402 |
Quarterly Financial Data (una_2
Quarterly Financial Data (unaudited) (Tables) | 12 Months Ended |
Dec. 31, 2019 | |
Quarterly Financial Information Disclosure [Abstract] | |
Schedule of Certain Unaudited Quarterly Financial Information | The following table presents certain unaudited quarterly financial information for the previous eight quarters. This information has been prepared on the same basis as the audited financial statements and includes all adjustments (consisting only of normal recurring adjustments) necessary to present fairly the unaudited quarterly results of operations set forth herein. For the Three Months Ended(1) March 31 June 30 September 30 December 31 (in thousands except per share data) 2019 Total revenue $ 2,780 $ 27,666 $ 4,208 $ 39,338 Total costs and expenses 43,585 48,802 53,131 64,919 Loss from operations (40,805 ) (21,136 ) (48,923 ) (25,581 ) Net loss (38,053 ) (17,862 ) (45,369 ) (23,575 ) Net loss per share- basic and diluted $ (0.74 ) $ (0.34 ) $ (0.86 ) $ (0.44 ) 2018 Total revenue $ 3,232 $ 3,685 $ 3,258 $ 3,816 Total costs and expenses 30,872 33,591 33,320 40,622 Loss from operations (27,640 ) (29,906 ) (30,062 ) (36,806 ) Net income (loss) (26,219 ) (28,938 ) (28,979 ) (34,734 ) Net loss per share- basic and diluted $ (0.58 ) $ (0.63 ) $ (0.63 ) $ (0.75 ) ______________________________________________________ (1) The amounts were computed independently for each quarter, and the sum of the quarters may not total the annual amounts. |
Summary of Significant Accoun_4
Summary of Significant Accounting Policies (Details) | 12 Months Ended | ||
Dec. 31, 2019USD ($)segmentstock-based_compensation_plan | Dec. 31, 2018USD ($) | Dec. 31, 2017USD ($) | |
Accounting Policies [Abstract] | |||
Allowance for doubtful accounts | $ 0 | $ 0 | |
Segment Information | |||
Number of operating segments | segment | 1 | ||
Debt Securities, Available-for-sale, Unrealized Loss Position | |||
Marketable securities, realized gain (loss) | $ 0 | 0 | $ 0 |
Continuous unrealized loss position, less than twelve months | 35,800,000 | 51,200,000 | |
Continuous unrealized loss position, twelve months or longer, fair value | 0 | 94,300,000 | |
Continuous unrealized loss position, fair value | 0 | 400,000 | |
Concentrations of Credit Risk and Off-Balance Sheet Risk | |||
Off-balance sheet risk, asset | 0 | ||
Off-balance sheet risk, liability | 0 | ||
Fair Value Measurement | |||
Transfers within the hierarchy | 0 | 0 | |
Property and Equipment | |||
Impairment losses | $ 0 | $ 0 | $ 0 |
Stock-Based Compensation | |||
Number of stock-based compensation plans | stock-based_compensation_plan | 2 |
Summary of Significant Accoun_5
Summary of Significant Accounting Policies - Schedule of Financial Instruments Carried at Fair Value (Details) - Recurring - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Assets: | ||
Total assets | $ 429,018 | $ 288,510 |
Liabilities: | ||
Total liabilities | 1,856 | 1,491 |
Common Stock Warrants | ||
Liabilities: | ||
Total liabilities | 1,856 | 1,491 |
Money Market Funds | ||
Assets: | ||
Total assets | 193,867 | 74,023 |
Corporate Obligations | ||
Assets: | ||
Total assets | 138,369 | 128,920 |
US Treasury Securities | ||
Assets: | ||
Total assets | 83,819 | 56,978 |
Certificates of Deposit | ||
Assets: | ||
Total assets | 493 | 1,715 |
Mortgage and Other Asset-Backed Securities | ||
Assets: | ||
Total assets | 12,470 | 26,874 |
Level 1 | ||
Assets: | ||
Total assets | 193,867 | 74,023 |
Liabilities: | ||
Total liabilities | 0 | 0 |
Level 1 | Common Stock Warrants | ||
Liabilities: | ||
Total liabilities | 0 | 0 |
Level 1 | Money Market Funds | ||
Assets: | ||
Total assets | 193,867 | 74,023 |
Level 1 | Corporate Obligations | ||
Assets: | ||
Total assets | 0 | 0 |
Level 1 | US Treasury Securities | ||
Assets: | ||
Total assets | 0 | 0 |
Level 1 | Certificates of Deposit | ||
Assets: | ||
Total assets | 0 | 0 |
Level 1 | Mortgage and Other Asset-Backed Securities | ||
Assets: | ||
Total assets | 0 | 0 |
Level 2 | ||
Assets: | ||
Total assets | 235,151 | 214,487 |
Liabilities: | ||
Total liabilities | 0 | 0 |
Level 2 | Common Stock Warrants | ||
Liabilities: | ||
Total liabilities | 0 | 0 |
Level 2 | Money Market Funds | ||
Assets: | ||
Total assets | 0 | 0 |
Level 2 | Corporate Obligations | ||
Assets: | ||
Total assets | 138,369 | 128,920 |
Level 2 | US Treasury Securities | ||
Assets: | ||
Total assets | 83,819 | 56,978 |
Level 2 | Certificates of Deposit | ||
Assets: | ||
Total assets | 493 | 1,715 |
Level 2 | Mortgage and Other Asset-Backed Securities | ||
Assets: | ||
Total assets | 12,470 | 26,874 |
Level 3 | ||
Assets: | ||
Total assets | 0 | 0 |
Liabilities: | ||
Total liabilities | 1,856 | 1,491 |
Level 3 | Common Stock Warrants | ||
Liabilities: | ||
Total liabilities | 1,856 | 1,491 |
Level 3 | Money Market Funds | ||
Assets: | ||
Total assets | 0 | 0 |
Level 3 | Corporate Obligations | ||
Assets: | ||
Total assets | 0 | 0 |
Level 3 | US Treasury Securities | ||
Assets: | ||
Total assets | 0 | 0 |
Level 3 | Certificates of Deposit | ||
Assets: | ||
Total assets | 0 | 0 |
Level 3 | Mortgage and Other Asset-Backed Securities | ||
Assets: | ||
Total assets | $ 0 | $ 0 |
Summary of Significant Accoun_6
Summary of Significant Accounting Policies - Summary of Changes in the Fair Value of Preferred and Common Stock Warrants (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2019 | Dec. 31, 2018 | |
Summary of changes in the fair value of the preferred and common stock warrant liability classified within Level 3 of the fair value hierarchy | ||
Beginning balance | $ 1,491 | $ 2,236 |
Change in fair value | 365 | 52 |
Exercises | 0 | (797) |
Ending balance | $ 1,856 | $ 1,491 |
Summary of Significant Accoun_7
Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Property and Equipment (Details) | 12 Months Ended |
Dec. 31, 2019 | |
Computer Equipment and Software | |
Property and Equipment | |
Estimated useful life | 3 years |
Office and laboratory equipment | |
Property and Equipment | |
Estimated useful life | 3 years |
Summary of Significant Accoun_8
Summary of Significant Accounting Policies - Schedule of Anti-dilutive Common Stock Equivalents Excluded from the Calculation of Diluted Net Income (Loss) per Share (Details) - shares shares in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Net Income (Loss) Per Share | |||
Anti-dilutive common stock equivalents excluded from the calculation of diluted net income (loss) per share (in shares) | 4,279 | 4,178 | 4,135 |
Stock Options | |||
Net Income (Loss) Per Share | |||
Anti-dilutive common stock equivalents excluded from the calculation of diluted net income (loss) per share (in shares) | 3,820 | 3,513 | 3,452 |
Common Stock Warrants | |||
Net Income (Loss) Per Share | |||
Anti-dilutive common stock equivalents excluded from the calculation of diluted net income (loss) per share (in shares) | 39 | 39 | 61 |
Shares issuable under employee stock purchase plan | |||
Net Income (Loss) Per Share | |||
Anti-dilutive common stock equivalents excluded from the calculation of diluted net income (loss) per share (in shares) | 23 | 18 | 18 |
Restricted Stock Units | |||
Net Income (Loss) Per Share | |||
Anti-dilutive common stock equivalents excluded from the calculation of diluted net income (loss) per share (in shares) | 397 | 608 | 604 |
Property and Equipment, Net - S
Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Property and equipment, net | |||
Total property and equipment | $ 38,046 | $ 35,139 | |
Accumulated depreciation and amortization | (31,234) | (28,033) | |
Property and equipment, net | 6,812 | 7,106 | |
Depreciation and amortization expense | 3,941 | 3,747 | $ 2,825 |
Computer Equipment and Software | |||
Property and equipment, net | |||
Total property and equipment | 1,767 | 1,712 | |
Office Equipment | |||
Property and equipment, net | |||
Total property and equipment | 672 | 672 | |
Laboratory Equipment | |||
Property and equipment, net | |||
Total property and equipment | 22,079 | 19,948 | |
Leasehold Improvements | |||
Property and equipment, net | |||
Total property and equipment | 12,347 | 11,668 | |
Construction in Progress | |||
Property and equipment, net | |||
Total property and equipment | $ 1,181 | $ 1,139 |
Restricted Cash (Details)
Restricted Cash (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 |
Cash and Cash Equivalents [Abstract] | ||||
Cash and cash equivalents | $ 237,677 | $ 144,052 | $ 100,150 | |
Restricted cash | 1,597 | 1,597 | 1,132 | |
Total cash, cash equivalents and restricted cash shown in the statement of cash flows | $ 239,274 | $ 145,649 | $ 101,282 | $ 21,896 |
Restricted Cash - Narrative (De
Restricted Cash - Narrative (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 |
Restricted Cash | |||
Letters of credit held in the form of certificates of deposits | $ 1,597 | $ 1,597 | $ 1,132 |
Certificates of Deposit | Letters of Credit | |||
Restricted Cash | |||
Letters of credit held in the form of certificates of deposits | $ 1,600 | $ 1,600 | $ 1,100 |
Cash, Cash Equivalents and Sh_3
Cash, Cash Equivalents and Short-term and Long-term Investments - Schedule of Available-for-Sale Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 |
Schedule of Available-for-sale Securities | |||
Cash and cash equivalents, amortized cost | $ 144,064 | ||
Gross Unrealized Losses | (12) | ||
Cash and cash equivalents due in 90 days or less | $ 237,677 | 144,052 | $ 100,150 |
Available-for-sale securities: | |||
Amortized Cost | 215,872 | 147,714 | |
Gross Unrealized Gains | 325 | 0 | |
Gross Unrealized Losses | (28) | (454) | |
Estimated Fair Value | 216,169 | 147,260 | |
Total cash, cash equivalents and available for sale securities | |||
Amortized Cost | 453,549 | 291,778 | |
Gross Unrealized Gains | 325 | 0 | |
Gross Unrealized Losses | (28) | (466) | |
Estimated Fair Value | 453,846 | 291,312 | |
Corporate Obligations | |||
Available-for-sale securities: | |||
Amortized Cost | 124,676 | 73,671 | |
Gross Unrealized Gains | 219 | 0 | |
Gross Unrealized Losses | (15) | (267) | |
Estimated Fair Value | 124,880 | 73,404 | |
US Treasury Securities | |||
Available-for-sale securities: | |||
Amortized Cost | 78,230 | 45,346 | |
Gross Unrealized Gains | 98 | 0 | |
Gross Unrealized Losses | (1) | (79) | |
Estimated Fair Value | 78,327 | 45,267 | |
Certificates of Deposit | |||
Available-for-sale securities: | |||
Amortized Cost | 490 | 1,715 | |
Gross Unrealized Gains | 3 | 0 | |
Gross Unrealized Losses | 0 | 0 | |
Estimated Fair Value | 493 | 1,715 | |
Asset-backed Securities | |||
Available-for-sale securities: | |||
Amortized Cost | 12,476 | 26,982 | |
Gross Unrealized Gains | 5 | 0 | |
Gross Unrealized Losses | (12) | (108) | |
Estimated Fair Value | $ 12,469 | $ 26,874 |
Accrued Expenses - Schedule of
Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Payables and Accruals [Abstract] | ||
Research and development | $ 11,844 | $ 8,144 |
Commercial | 1,027 | 0 |
Employee compensation | 9,932 | 7,975 |
Professional services | 976 | 621 |
Accrued purchases | 119 | 351 |
Other | 997 | 1,118 |
Total accrued expenses | $ 24,895 | $ 18,209 |
Warrants - Summary of Shares Is
Warrants - Summary of Shares Issuable Upon Exercise of Outstanding Warrants (Details) - $ / shares shares in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Class of Warrant or Right | ||
Number of outstanding warrants (in shares) | 39 | 39 |
Weighted-average exercise price per share (in dollars per share) | $ 5.88 | |
Expiring between June 10, 2020 to July 9, 2020 | ||
Class of Warrant or Right | ||
Number of outstanding warrants (in shares) | 39 | 39 |
Weighted-average exercise price per share (in dollars per share) | $ 5.88 |
Stockholders' Equity (Details)
Stockholders' Equity (Details) $ / shares in Units, $ in Thousands | Feb. 12, 2019USD ($) | Jan. 18, 2019USD ($)$ / sharesshares | Oct. 04, 2017shares | Sep. 25, 2017USD ($)$ / sharesshares | Dec. 31, 2019USD ($)vote$ / sharesshares | Dec. 31, 2018USD ($)shares | Dec. 31, 2017USD ($) |
Common stock | |||||||
Price per share (in dollars per share) | $ / shares | $ 43 | $ 37 | |||||
Proceeds from issuance of common stock from follow-on public offering, net of issuance costs | $ | $ 248,200 | $ 215,800 | $ 215,800 | $ 248,130 | $ 0 | $ 215,802 | |
Preferred stock (in shares) | 25,000,000 | ||||||
Preferred stock, shares issued (in shares) | 0 | 0 | |||||
Preferred stock, shares outstanding (in shares) | 0 | 0 | |||||
Number of votes for each share of common stock held | vote | 1 | ||||||
Dividends declared on common stock (in dollars per share) | $ / shares | $ 0 | ||||||
Common Stock | |||||||
Common stock | |||||||
Public offering share amount (in shares) | 5,348,838 | 810,810 | 5,405,406 | ||||
Number of additional shares available for purchase (in shares) | 802,325 |
Stockholders' Equity - Schedule
Stockholders' Equity - Schedule of Common Stock Reserved for Future Issuance (Details) - shares | Dec. 31, 2019 | Sep. 04, 2013 |
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 34,013,000 | |
Conversion of Preferred Stock | Unissued, but Designated, Preferred Stock | ||
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 25,000,000 | |
Common Stock Warrants | ||
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 39,000 | |
Stock Compensation Plan | ||
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 3,820,000 | |
Restricted Stock | ||
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 397,000 | |
Stock Options | ||
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 4,634,000 | |
2013 ESPP | ||
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 275,000 | |
2013 ESPP | Employee Stock Purchase Plan | ||
Common stock | ||
Total shares of authorized common stock reserved for future issuance (in shares) | 122,589 |
Significant Agreements - Sotate
Significant Agreements - Sotatercept Agreement (Details) | Sep. 24, 2013USD ($) | Jan. 01, 2013 | Feb. 20, 2008USD ($)discovery_stage_compound | Dec. 31, 2019USD ($) | Sep. 30, 2019USD ($) | Jun. 30, 2019USD ($) | Mar. 31, 2019USD ($) | Dec. 31, 2018USD ($) | Sep. 30, 2018USD ($) | Jun. 30, 2018USD ($) | Mar. 31, 2018USD ($) | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) | Dec. 31, 2017USD ($) | Aug. 02, 2011USD ($) |
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Revenue | $ 39,338,000 | $ 4,208,000 | $ 27,666,000 | $ 2,780,000 | $ 3,816,000 | $ 3,258,000 | $ 3,685,000 | $ 3,232,000 | $ 73,993,000 | $ 13,991,000 | $ 13,481,000 | ||||
Collaboration, License, and Option Agreement | Restated Sotatercept Agreement | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Percentage of development costs for which collaborator is responsible | 100.00% | ||||||||||||||
Potential royalty rate (as a percent) | 20.00% | ||||||||||||||
Original Sotatercept Agreement | Collaboration Arrangement | Upfront License and Option Payments | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Revenue | $ 45,000,000 | $ 45,000,000 | |||||||||||||
Bristol-Myers Squibb Company (BMS, formerly Celgene) | Original Sotatercept Agreement | Collaboration Arrangement | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Percentage of development costs for which collaborator is responsible | 100.00% | ||||||||||||||
Equity purchased | $ 5,000,000 | ||||||||||||||
Bristol-Myers Squibb Company (BMS, formerly Celgene) | Original Sotatercept Agreement | Collaboration Arrangement | Discovery Stage Compounds | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Number of license options granted | discovery_stage_compound | 3 | ||||||||||||||
Bristol-Myers Squibb Company (BMS, formerly Celgene) | Original Sotatercept Agreement | Collaboration Arrangement | Sotatercept | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Potential royalty rate (as a percent) | 20.00% | ||||||||||||||
Common Stock | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Original Sotatercept Agreement | Collaboration Arrangement | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Equity purchased | $ 10,000,000 | ||||||||||||||
Maximum | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Amended Sotatercept Agreement | Collaboration Arrangement | Discovery Stage Compounds | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Collaborative arrangement option fees potential | $ 30,000,000 | ||||||||||||||
Maximum | Clinical Milestones | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Amended Sotatercept Agreement | Collaboration Arrangement | Discovery Stage Compounds | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Contingent milestone payments | 25,500,000 | ||||||||||||||
Maximum | Clinical Milestones | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Amended Sotatercept Agreement | Collaboration Arrangement | Sotatercept | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Contingent milestone payments | 27,000,000 | ||||||||||||||
Maximum | Regulatory Milestones | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Amended Sotatercept Agreement | Collaboration Arrangement | Discovery Stage Compounds | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Contingent milestone payments | 142,500,000 | ||||||||||||||
Maximum | Regulatory Milestones | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Amended Sotatercept Agreement | Collaboration Arrangement | Sotatercept | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Contingent milestone payments | 190,000,000 | ||||||||||||||
Maximum | Commercial Milestones | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Amended Sotatercept Agreement | Collaboration Arrangement | Discovery Stage Compounds | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Contingent milestone payments | 150,000,000 | ||||||||||||||
Maximum | Commercial Milestones | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Amended Sotatercept Agreement | Collaboration Arrangement | Sotatercept | |||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | |||||||||||||||
Contingent milestone payments | $ 150,000,000 |
Significant Agreements - REBLOZ
Significant Agreements - REBLOZYL Agreement (Details) - USD ($) | Jan. 01, 2013 | Feb. 20, 2008 | Aug. 31, 2011 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 |
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Revenue | $ 39,338,000 | $ 4,208,000 | $ 27,666,000 | $ 2,780,000 | $ 3,816,000 | $ 3,258,000 | $ 3,685,000 | $ 3,232,000 | $ 73,993,000 | $ 13,991,000 | $ 13,481,000 | |||
Original Sotatercept Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Percentage of development costs for which collaborator is responsible | 100.00% | |||||||||||||
REBLOZYL Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Percentage of development costs for which collaborator is responsible | 100.00% | |||||||||||||
Maximum | REBLOZYL Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Termination notice period | 180 days | |||||||||||||
Minimum | REBLOZYL Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Termination notice period | 45 days | |||||||||||||
Clinical Milestones | Maximum | REBLOZYL Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Potential milestone payments receivable | $ 32,500,000 | |||||||||||||
Regulatory Milestones | Maximum | REBLOZYL Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Potential milestone payments receivable | 105,000,000 | |||||||||||||
Commercial Milestones | Maximum | REBLOZYL Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Potential milestone payments receivable | 80,000,000 | |||||||||||||
Development, Regulatory and Commercial Milestones | Maximum | REBLOZYL Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Potential milestone payments receivable | $ 125,000,000 | $ 125,000,000 | ||||||||||||
Sotatercept | Original Sotatercept Agreement | Bristol-Myers Squibb Company (BMS, formerly Celgene) | Collaboration Arrangement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Potential royalty rate (as a percent) | 20.00% | |||||||||||||
Nonrefundable Upfront Payments | REBLOZYL Agreement | ||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||
Revenue | $ 25,000,000 | $ 25,000,000 |
Significant Agreements - Accoun
Significant Agreements - Accounting Analysis (Details) - USD ($) $ in Thousands | Nov. 08, 2019 | Jun. 04, 2019 | Feb. 20, 2008 | Aug. 31, 2011 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2018 |
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | $ 39,338 | $ 4,208 | $ 27,666 | $ 2,780 | $ 3,816 | $ 3,258 | $ 3,685 | $ 3,232 | $ 73,993 | $ 13,991 | $ 13,481 | |||||
Luspatercept Agreement and Amended Sotatercept Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | 192,300 | |||||||||||||||
Luspatercept | Collaboration, License, and Option Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Payments received | 181,900 | |||||||||||||||
Luspatercept | Regulatory Milestone | Collaboration, License, and Option Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Milestone payment receivable on commencement of trial or study | $ 25,000 | 25,000 | ||||||||||||||
Nonrefundable Upfront Payments | REBLOZYL Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | $ 25,000 | 25,000 | ||||||||||||||
Upfront License and Option Payments | Original Sotatercept Agreement | Collaboration Arrangement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | $ 45,000 | 45,000 | ||||||||||||||
Development and Manufacturing Activities | REBLOZYL Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | 47,900 | |||||||||||||||
Development and Manufacturing Activities | Amended Sotatercept Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | 14,900 | |||||||||||||||
Milestone Achievements | Luspatercept Agreement and Amended Sotatercept Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | 59,500 | |||||||||||||||
Sotatercept | Collaboration, License, and Option Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Payments received | 44,700 | |||||||||||||||
Cost Sharing | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | 13,993 | 13,991 | 12,940 | |||||||||||||
Cost Sharing | Collaboration, License, and Option Agreement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Revenue | 14,000 | $ 14,000 | $ 12,900 | |||||||||||||
Accounting Standards Update 2014-09 | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Effect of adoption of ASU | $ 3,705 | |||||||||||||||
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606 | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Deferred revenue | 500 | |||||||||||||||
Difference between the estimated payments and the estimated selling prices | 3,200 | |||||||||||||||
Bristol-Myers Squibb Company (BMS, formerly Celgene) | REBLOZYL Agreement | Collaboration Arrangement | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Contract with customer, liability, change in timeframe, performance obligation satisfied, revenue recognized | $ 35,000 | $ 25,000 | ||||||||||||||
Revenue recognized | $ 60,000 | |||||||||||||||
Accumulated Deficit | Accounting Standards Update 2014-09 | ||||||||||||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||||||||||||
Effect of adoption of ASU | $ 3,705 |
Significant Agreements - Other
Significant Agreements - Other (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended | ||||
Dec. 31, 2019 | May 31, 2014 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2004 | |
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Research and development | $ 153,953 | $ 103,902 | $ 89,726 | |||
License Agreement with a Non-profit Institution | Non-collaborative Arrangement Transactions | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Research and development | 3,700 | 100 | 100 | |||
License Agreement With Antibody Technology Company | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Research and development | 2,100 | $ 100 | $ 1,600 | |||
License Agreement With Fulcrum Therapeutics | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Research and development | $ 10,000 | |||||
Minimum | License Agreement with a Non-profit Institution | Non-collaborative Arrangement Transactions | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Milestone fees payable as percentage of research and U.S. development progress and sublicensing revenue | 10.00% | |||||
Royalty payable as percentage of net sales | 1.00% | |||||
Maximum | License Agreement with a Non-profit Institution | Non-collaborative Arrangement Transactions | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Milestone fees payable as percentage of research and U.S. development progress and sublicensing revenue | 25.00% | |||||
Royalty payable as percentage of net sales | 3.50% | |||||
Development Milestones | Sotatercept | Maximum | Non-collaborative Arrangement Transactions | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Total potential milestone payments | $ 2,000 | |||||
Development Milestones | REBLOZYL Agreement | Maximum | Non-collaborative Arrangement Transactions | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Total potential milestone payments | $ 700 | |||||
Additional Research Fees | License Agreement With Antibody Technology Company | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Collaborative arrangement amount paid and expensed | $ 300 | |||||
Additional Research Fees | License Agreement With Fulcrum Therapeutics | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Collaborative arrangement amount paid and expensed | $ 10,000 | |||||
Additional Research Fees | Maximum | License Agreement With Fulcrum Therapeutics | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Total potential milestone payments | 143,500 | |||||
Research, Development and Commercial Milestone Payments | Maximum | License Agreement With Fulcrum Therapeutics | ||||||
Collaborative Arrangements and Non-collaborative Arrangement Transactions | ||||||
Total potential milestone payments | $ 295,000 |
Stock-Based Compensation (Detai
Stock-Based Compensation (Details) $ / shares in Units, $ in Thousands | Sep. 04, 2013shares | Dec. 31, 2019USD ($)stock-based_compensation_plan$ / sharesshares | Dec. 31, 2018USD ($)$ / sharesshares | Dec. 31, 2017USD ($)$ / sharesshares |
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Number of stock-based compensations plans | stock-based_compensation_plan | 2 | |||
Shares reserved for issuance (in shares) | 34,013,000 | |||
Stock compensation expense | $ | $ 22,995 | $ 24,569 | $ 28,248 | |
Expected dividend yield | 0.00% | |||
Shares granted during period (in shares) | 924,000 | |||
Exercise of stock options (in shares) | 344,000 | |||
2003 Plan | ||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Number of shares of common stock which may be granted (in shares) | 0 | |||
Remaining shares reserved for issuance (in shares) | 155,884 | |||
2013 Plan | ||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Shares reserved for issuance (in shares) | 1,500,000 | |||
Remaining shares reserved for issuance (in shares) | 4,634,133 | |||
Additional shares authorized under new plan (in shares) | 1,344,116 | |||
Annual increase in shares authorized under plan, shares threshold (in shares) | 3,150,000 | |||
Percentage threshold of outstanding shares as of December 31 of each year for calculation of annual increase in authorized shares under the plan | 4.00% | |||
2003 and 2013 Plans | ||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Expiration period of options | 10 years | |||
Vesting period of stock options and restricted stock awards | 4 years | |||
Stock compensation expense | $ | $ 1,000 | $ 2,400 | $ 4,900 | |
Shares granted during period (in shares) | 923,508 | 942,271 | 701,384 | |
Weighted average grant date fair value (in dollars per share) | $ / shares | $ 23.65 | $ 25.05 | $ 18.58 | |
Exercise of stock options (in shares) | 344,257 | 779,711 | 474,056 | |
Total proceeds from options exercised | $ | $ 10,100 | $ 15,900 | $ 3,900 | |
Aggregate intrinsic value of options exercised | $ | 4,900 | 19,300 | 10,200 | |
Unrecognized compensation expense related to unvested stock options | $ | $ 28,400 | |||
Weighted-average period of recognition (in years) | 2 years 4 months 24 days | |||
2013 ESPP | ||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Shares reserved for issuance (in shares) | 275,000 | |||
Purchase price of common stock expressed as a percentage of the fair value of a share of common stock | 85.00% | |||
Stock compensation expense | $ | $ 400 | $ 400 | $ 300 | |
Restricted Stock Units | 2003 and 2013 Plans | ||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Vesting period of stock options and restricted stock awards | 3 years | |||
Restricted Stock Units | Certain Individuals | ||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Weighted-average period of recognition (in years) | 1 year 9 months 18 days | |||
Unrecognized compensation expense related to unvested restricted stock units | $ | $ 10,500 | |||
Employee Stock Purchase Plan | 2013 ESPP | ||||
Share-based Compensation Arrangement by Share-based Payment Award | ||||
Shares reserved for issuance (in shares) | 122,589 |
Stock-Based Compensation - Sche
Stock-Based Compensation - Schedule of Total Compensation Cost Recognized for All Stock-based Awards (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | |||
Total compensation cost recognized | $ 22,995 | $ 24,569 | $ 28,248 |
Research and Development | |||
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | |||
Total compensation cost recognized | 9,943 | 12,669 | 14,227 |
Selling, general and administrative | |||
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | |||
Total compensation cost recognized | $ 13,052 | $ 11,900 | $ 14,021 |
Stock-Based Compensation - Sc_2
Stock-Based Compensation - Schedule of Stock Option Valuation Assumptions (Details) | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Share-based Compensation Arrangement by Share-based Payment Award | |||
Expected dividend yield | 0.00% | ||
Equity Option | |||
Share-based Compensation Arrangement by Share-based Payment Award | |||
Expected volatility | 58.60% | 62.80% | 65.70% |
Expected term (in years) | 6 years | 6 years | 6 years |
Risk-free interest rate | 2.39% | 2.70% | 2.13% |
Expected dividend yield | 0.00% | 0.00% | 0.00% |
Stock-Based Compensation - Summ
Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands | 12 Months Ended |
Dec. 31, 2019USD ($)$ / sharesshares | |
Number of Grants (in thousands) | |
Outstanding at beginning of period (in shares) | shares | 3,513 |
Granted (in shares) | shares | 924 |
Exercised (in shares) | shares | (344) |
Canceled or forfeited (in shares) | shares | (273) |
Outstanding at end of period (in shares) | shares | 3,820 |
Exercisable (in shares) | shares | 2,400 |
Weighted- Average Exercise Price Per Share | |
Outstanding at beginning of period (in dollars per share) | $ / shares | $ 34.40 |
Granted (in dollars per share) | $ / shares | 42.32 |
Exercised (in dollars per share) | $ / shares | 29.33 |
Canceled or forfeited (in dollars per share) | $ / shares | 41.64 |
Outstanding at end of period (in dollars per share) | $ / shares | 36.26 |
Exercisable (in dollars per share) | $ / shares | $ 33.76 |
Weighted- Average Contractual Life (in years) | |
Outstanding at end of period (in years) | 6 years 9 months 21 days |
Exercisable (in years) | 5 years 9 months 18 days |
Aggregate Intrinsic Value | |
Outstanding at end of period (in dollars) | $ | $ 64,146 |
Exercisable (in dollars) | $ | $ 46,258 |
Stock-based Compensation - Sc_3
Stock-based Compensation - Schedule of Restricted Stock Unit Activity and Performance-Based Restricted Stock Units (Details) shares in Thousands | 12 Months Ended |
Dec. 31, 2019$ / sharesshares | |
Restricted Stock Units | |
Number of Stock Units (in thousands) | |
Unvested balance at beginning of period (in units) | shares | 372 |
Granted (in units) | shares | 216 |
Vested (in units) | shares | (124) |
Forfeited (in units) | shares | (67) |
Unvested balance at end of period (in units) | shares | 397 |
Weighted- Average Grant Date Fair Value Per Share | |
Unvested balance at beginning of period (in dollars per share) | $ / shares | $ 36.53 |
Granted (in dollars per share) | $ / shares | 41.43 |
Vested (in dollars per share) | $ / shares | 34.59 |
Forfeited (in dollars per share) | $ / shares | 40.25 |
Unvested balance at end of period (in dollars per share) | $ / shares | $ 39.20 |
Performance-Based Restricted Stock Units | |
Number of Stock Units (in thousands) | |
Unvested balance at beginning of period (in units) | shares | 236 |
Granted (in units) | shares | 0 |
Vested (in units) | shares | (227) |
Forfeited (in units) | shares | (9) |
Unvested balance at end of period (in units) | shares | 0 |
Weighted- Average Grant Date Fair Value Per Share | |
Unvested balance at beginning of period (in dollars per share) | $ / shares | $ 31.42 |
Granted (in dollars per share) | $ / shares | 0 |
Vested (in dollars per share) | $ / shares | 31.44 |
Forfeited (in dollars per share) | $ / shares | 31.09 |
Unvested balance at end of period (in dollars per share) | $ / shares | $ 0 |
401(k) Savings Plan (Details)
401(k) Savings Plan (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Retirement Benefits [Abstract] | |||
Matching contribution, amount per employee | $ 10,000 | $ 8,500 | $ 7,000 |
Expenses related to 401(k) Savings Plan | $ 1,700,000 | $ 1,100,000 | $ 700,000 |
Income Taxes (Details)
Income Taxes (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Income Tax Disclosure [Abstract] | |||
Income tax benefit from realized current year losses offset by unrealized gains | $ 62,000 | $ 27,000 | |
State tax expense (benefit) | $ 32,000 | ||
Loss before income taxes | 124,900,000 | 118,900,000 | 108,400,000 |
Increase in valuation allowance | 43,000,000 | 37,300,000 | $ 9,100,000 |
Operating loss carryforwards | |||
Operating loss carryforwards, subject to expiration | 438,000,000 | ||
Income tax penalties and interest accrued | 0 | 0 | |
Income tax penalties and interest expense | 0 | 0 | |
Federal | |||
Operating loss carryforwards | |||
Net operating loss carryforwards | 666,300,000 | 556,000,000 | |
Operating loss carryforwards, not subject to expiration | 228,300,000 | ||
State | |||
Operating loss carryforwards | |||
Net operating loss carryforwards | 689,800,000 | 515,000,000 | |
Operating loss carryforwards, subject to expiration | 689,400,000 | ||
Operating loss carryforwards, not subject to expiration | 400,000 | ||
Research and development | Federal | |||
Operating loss carryforwards | |||
Tax credit carryforwards | 14,500,000 | 10,700,000 | |
Research and development | State | |||
Operating loss carryforwards | |||
Tax credit carryforwards | $ 8,700,000 | $ 7,100,000 |
Income Taxes Income Taxes - Com
Income Taxes Income Taxes - Components of the Company's Deferred Tax Assets (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 |
Income Tax Disclosure [Abstract] | ||
U.S. and state net operating loss carryforwards | $ 184,355 | $ 149,170 |
Research and development credits | 21,345 | 16,340 |
Stock compensation | 14,024 | 13,819 |
Lease liabilities | 7,090 | |
Accruals and other temporary differences | 5,584 | 3,626 |
Total deferred tax assets | 232,398 | 182,955 |
Right of use asset | (6,429) | |
Less valuation allowance | (225,969) | (182,955) |
Net deferred tax assets | $ 0 | $ 0 |
Income Taxes - Schedule of Effe
Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) | 12 Months Ended | ||
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Income Tax Disclosure [Abstract] | |||
Federal income tax expense at statutory rate | 21.00% | 21.00% | 34.00% |
State income tax, net of federal benefit | 9.90% | 7.00% | 5.60% |
Permanent differences | 0.20% | 2.00% | 1.90% |
Research and development credit | 4.20% | 3.20% | 1.90% |
Tax reform rate change | 0 | 0 | (0.547) |
Other | (0.90%) | (0.60%) | (0.30%) |
Change in valuation allowance | (34.40%) | (32.60%) | 11.60% |
Effective income tax rate | 0.00% | 0.00% | 0.00% |
Leases - Narrative (Details)
Leases - Narrative (Details) ft² in Thousands, $ in Thousands | 12 Months Ended | |||
Dec. 31, 2019USD ($)ft²building | Dec. 31, 2018USD ($) | Dec. 31, 2017USD ($) | Jan. 01, 2019USD ($) | |
Lessee, Lease, Description [Line Items] | ||||
Operating lease, leased area | ft² | 125 | |||
Operating lease, number of buildings | building | 5 | |||
IBR rate for operating leases | 10.00% | |||
Right-of-use - operating leases | $ 23,908 | |||
Operating lease, liability | 26,384 | |||
Operating lease, expense | 8,200 | |||
Operating lease, payments | $ 8,400 | |||
Operating leases, rent expense | $ 5,800 | $ 4,800 | ||
Minimum | ||||
Lessee, Lease, Description [Line Items] | ||||
Operating lease, extension term | 3 years | |||
Maximum | ||||
Lessee, Lease, Description [Line Items] | ||||
Operating lease, extension term | 5 years | |||
Accounting Standards Update 2016-02 | ||||
Lessee, Lease, Description [Line Items] | ||||
Right-of-use - operating leases | $ 29,100 | |||
Operating lease, liability | 31,000 | |||
Deferred rent | 2,700 | |||
Prepaid rent | $ 700 |
Leases - Minimum Lease Payments
Leases - Minimum Lease Payments (Details) $ in Thousands | Dec. 31, 2019USD ($) |
Leases [Abstract] | |
2020 | $ 8,610 |
2021 | 8,336 |
2022 | 8,409 |
2023 | 6,450 |
Total Lease Payments | 31,805 |
Less: imputed interest | (5,421) |
Total operating lease liabilities | $ 26,384 |
Leases - Lease Costs (Details)
Leases - Lease Costs (Details) | Dec. 31, 2019 |
Leases [Abstract] | |
Weighted average remaining lease term | 3 years 8 months 12 days |
Weighted average discount rate | 10.59% |
Leases - Maturity Schedule Prio
Leases - Maturity Schedule Prior to the Adoptions of ASC 842 (Details) $ in Thousands | Dec. 31, 2018USD ($) |
Leases [Abstract] | |
2019 | $ 8,195 |
2020 | 8,438 |
2021 | 8,180 |
2022 | 8,256 |
2023 | 6,333 |
Total future lease payments | $ 39,402 |
Related Party Transactions (Det
Related Party Transactions (Details) - Bristol-Myers Squibb Company (BMS, formerly Celgene) - shares | 1 Months Ended | ||||
Jan. 31, 2019 | Sep. 30, 2017 | Jan. 31, 2016 | Dec. 31, 2019 | Dec. 31, 2018 | |
Common Stock | |||||
Related Party Transaction [Line Items] | |||||
Shares purchased by collaborators (in shares) | 706,206 | 745,592 | 800,000 | ||
Bristol-Myers Squibb Company (BMS, formerly Celgene) | |||||
Related Party Transaction [Line Items] | |||||
Ownership percentage of entity's fully diluted equity | 12.00% | 12.20% |
Quarterly Financial Data (una_3
Quarterly Financial Data (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | |
Quarterly Financial Information Disclosure [Abstract] | |||||||||||
Revenue | $ 39,338 | $ 4,208 | $ 27,666 | $ 2,780 | $ 3,816 | $ 3,258 | $ 3,685 | $ 3,232 | $ 73,993 | $ 13,991 | $ 13,481 |
Total costs and expenses | 64,919 | 53,131 | 48,802 | 43,585 | 40,622 | 33,320 | 33,591 | 30,872 | 210,438 | 138,405 | 123,464 |
Income (loss) from operations | (25,581) | (48,923) | (21,136) | (40,805) | (36,806) | (30,062) | (29,906) | (27,640) | (136,445) | (124,414) | (109,983) |
Net loss | $ (23,575) | $ (45,369) | $ (17,862) | $ (38,053) | $ (34,734) | $ (28,979) | $ (28,938) | $ (26,219) | $ (124,858) | $ (118,871) | $ (108,454) |
Net loss per share applicable to common stockholders-basic and diluted (in dollars per share) | $ (0.44) | $ (0.86) | $ (0.34) | $ (0.74) | $ (0.75) | $ (0.63) | $ (0.63) | $ (0.58) | $ (2.38) | $ (2.59) | $ (2.68) |
Uncategorized Items - xlrn-2019
Label | Element | Value |
Accounting Standards Update 2016-09 [Member] | ||
Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | $ 0 |
Accounting Standards Update 2016-09 [Member] | Retained Earnings [Member] | ||
Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | (79,000) |
Accounting Standards Update 2016-09 [Member] | Additional Paid-in Capital [Member] | ||
Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | 79,000 |
Accounting Standards Update 2018-07 [Member] | ||
Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | 0 |
Accounting Standards Update 2018-07 [Member] | Retained Earnings [Member] | ||
Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | 1,641,000 |
Accounting Standards Update 2018-07 [Member] | Additional Paid-in Capital [Member] | ||
Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | $ (1,641,000) |