Verastem (VSTM) 10-K18 Mar 212020 FY Annual reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2020	Mar. 17, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2020
Entity File Number	001-35403
Entity Registrant Name	Verastem, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	27-3269467
Entity Address, Address Line One	117 Kendrick Street, Suite 500
Entity Address, City or Town	Needham
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02494
City Area Code	781
Local Phone Number	292-4200
Title of 12(b) Security	Common Stock, $0.0001 par value
Trading Symbol	VSTM
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 290,695,420
Entity Common Stock, Shares Outstanding		171,665,716
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Central Index Key	0001526119
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 67,782	$ 43,514
Short-term investments	73,444	31,992
Accounts receivable, net	239	2,524
Inventory		3,096
Prepaid expenses and other current assets	3,473	3,835
Total current assets	144,938	84,961
Property and equipment, net	416	947
Right-of-use asset, net	2,726	3,077
Intangible assets, net		20,008
Restricted cash	241	35,241
Long-term investments	5,995
Other assets	33	812
Total assets	154,349	145,046
Current liabilities:
Accounts payable	1,875	9,655
Accrued expenses	14,660	19,365
Lease liability, short-term	558	420
Derivative liability, short-term		450
Total current liabilities	17,093	29,890
Non-current liabilities:
Long-term debt		35,067
Convertible senior notes	19,051	68,556
Lease liability, long-term	2,931	3,489
Other non-current liabilities		870
Total liabilities	39,075	137,872
Stockholders' equity:
Preferred stock, $0.0001 par value; 5,000 shares authorized, no shares issued and outstanding at December 31, 2020 and December 31, 2019, respectively
Common stock, $0.0001 par value; 300,000 and 200,000 shares authorized, 170,456 and 80,118 shares issued and outstanding at December 31, 2020 and December 31, 2019, respectively	17	8
Additional paid-in capital	707,715	531,937
Accumulated other comprehensive income	53	14
Accumulated deficit	(592,511)	(524,785)
Total stockholders' equity	115,274	7,174
Total liabilities and stockholders' equity	$ 154,349	$ 145,046

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares shares in Thousands	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED BALANCE SHEETS
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000	5,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	300,000	200,000
Common stock, shares issued	170,456	80,118
Common stock, shares outstanding	170,456	80,118

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue:
Total revenue	$ 88,516	$ 17,456	$ 26,718
Operating expenses:
Cost of sales - product	1,765	1,238	165
Cost of sales - intangible amortization	793	1,569	423
Cost of sales - sale of COPIKTRA license and related assets	31,187
Research and development	41,376	45,778	43,648
Selling, general and administrative	62,755	101,212	77,265
Total operating expenses	137,876	149,797	121,501
Loss from operations	(49,360)	(132,341)	(94,783)
Other (expense)/ income	(1,313)	(641)	25,556
Interest income	515	4,381	2,603
Interest expense	(15,794)	(20,608)	(5,810)
Loss on debt extinguishment	(1,580)
Net loss before income taxes	(67,532)	(149,209)	(72,434)
Income tax expense	(194)	0	0
Net loss	$ (67,726)	$ (149,209)	$ (72,434)
Net loss per share-basic	$ (0.44)	$ (2)	$ (1.12)
Net loss per share-diluted	$ (0.44)	$ (2)	$ (1.37)
Weighted average common shares outstanding used in computing:
Net loss per share-basic (in shares)	153,330	74,578	64,962
Net loss per share-diluted (in shares)	153,330	74,578	69,321
Net loss	$ (67,726)	$ (149,209)	$ (72,434)
Unrealized gain (loss) on available-for-sale securities	39	(113)	129
Comprehensive loss	(67,687)	(149,322)	(72,305)
Product revenue, net
Revenue:
Total revenue	15,232	12,339	1,718
License and collaboration revenue
Revenue:
Total revenue	2,912	$ 5,117	$ 25,000
Copiktra license and related assets
Revenue:
Total revenue	70,000
Transition Services Revenue
Revenue:
Total revenue	$ 372

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common stock	Additional paid-in capital	Accumulated other comprehensive (loss) income	Accumulated deficit	Total
Balance at Dec. 31, 2017	$ 5	$ 360,823	$ (2)	$ (303,142)	$ 57,684
Balance (in shares) at Dec. 31, 2017	50,800,908
Increase (Decrease) in Stockholders' Equity
Net loss				(72,434)	(72,434)
Unrealized gain (loss) on available-for-sale marketable securities			129		$ 129
Conversion of Notes into common stock (in shares)					20,936,548
Issuance of common stock resulting from follow-on offering, net of issuance costs	$ 1	81,188			$ 81,189
Issuance of common stock resulting from follow-on offering, net of issuance costs (in shares)	16,111,110
Issuance of common stock resulting from at-the-market transactions, net of issuance costs	$ 1	24,275			24,276
Issuance of common stock resulting from at-the-market transactions, net of issuance costs (in shares)	6,481,475
Issuance of common stock resulting from exercise of stock options		809			809
Issuance of common stock resulting from exercise of stock options (in shares)	412,851
Reclassification of derivative liability to equity		25,975			25,975
Stock-based compensation expense		6,671			6,671
Balance at Dec. 31, 2018	$ 7	499,741	127	(375,576)	124,299
Balance (in shares) at Dec. 31, 2018	73,806,344
Increase (Decrease) in Stockholders' Equity
Net loss				(149,209)	(149,209)
Unrealized gain (loss) on available-for-sale marketable securities			(113)		(113)
Conversion of Notes into common stock	$ 1	9,516			9,517
Conversion of Notes into common stock (in shares)	5,767,872
Change in fair value of conversion option of Notes on exchange		13,640			13,640
Issuance of common stock under Employee Stock Purchase Plan		439			439
Issuance of common stock under Employee Stock Purchase Plan (in shares)	341,701
Issuance of common stock resulting from vesting of restricted stock units		(68)			(68)
Issuance of common stock resulting from vesting of restricted stock units (in shares)	109,707
Issuance of common stock resulting from exercise of stock options		130			130
Issuance of common stock resulting from exercise of stock options (in shares)	91,907
Stock-based compensation expense		8,539			8,539
Balance at Dec. 31, 2019	$ 8	531,937	14	(524,785)	$ 7,174
Balance (in shares) at Dec. 31, 2019	80,117,531				80,118,000
Increase (Decrease) in Stockholders' Equity
Net loss				(67,726)	$ (67,726)
Unrealized gain (loss) on available-for-sale marketable securities			39		39
Conversion of Notes into common stock	$ 3	57,411			57,414
Conversion of Notes into common stock (in shares)	34,796,350
Change in fair value of conversion option of Notes on exchange		2,331			2,331
Issuance of common stock under Employee Stock Purchase Plan		407			407
Issuance of common stock under Employee Stock Purchase Plan (in shares)	358,193
Issuance of common stock resulting from vesting of restricted stock units		(1,120)			(1,120)
Issuance of common stock resulting from vesting of restricted stock units (in shares)	421,695
Issuance of common stock resulting from at-the-market transactions, net of issuance costs	$ 1	12,229			12,230
Issuance of common stock resulting from at-the-market transactions, net of issuance costs (in shares)	6,769,559
Issuance of common stock resulting from exercise of stock options		2,578			2,578
Issuance of common stock resulting from exercise of stock options (in shares)	1,481,223
Issuance of common stock resulting from private investment in public equity offering, net of issuance costs	$ 5	93,824			93,829
Issuance of common stock resulting from private investment in public equity offering, net of issuance costs (in shares)	46,511,628
Stock-based compensation expense		8,118			8,118
Balance at Dec. 31, 2020	$ 17	$ 707,715	$ 53	$ (592,511)	$ 115,274
Balance (in shares) at Dec. 31, 2020	170,456,179				170,456,000

CONSOLIDATED STATEMENTS OF ST_2

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2018
Follow-on offerings
Issuance of common stock, issuance costs		$ 361
At-the-market equity offering program
Issuance of common stock, issuance costs	$ 55	$ 0
Private Investment in Public Equity (PIPE)
Issuance of common stock, issuance costs	$ 6,171

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net loss	$ (67,726)	$ (149,209)	$ (72,434)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	531	429	996
Amortization of acquired intangible asset	793	1,569	423
Amortization of right-of-use asset and lease liability	(69)	181
Stock-based compensation expense	8,118	8,539	6,671
Loss on debt extinguishment	1,580
Amortization of deferred financing costs, debt discounts and premiums and discounts on available-for-sale marketable securities	10,319	7,131	1,814
Change in fair value of interest make whole provision and conversion option for Notes	1,313	641	(25,556)
Gain on sale of fixed assets			(79)
Changes in operating assets and liabilities:
Accounts receivable, net	2,285	(2,218)	(306)
Inventory	3,096	(2,769)	(327)
Prepaid expenses, other current assets and other assets	634	(877)	(1,167)
Accounts payable	(7,976)	(598)	1,048
Accrued expenses and other liabilities	(4,999)	(1,707)	13,902
Other long-term liabilities	(870)	370	500
Intangible assets & property, plant and equipment	19,465
Net cash used in operating activities	(33,506)	(138,518)	(74,515)
Investing activities
Purchases of property and equipment	(33)	(7)	(1,507)
Sales of property and equipment			82
Acquisition of intangible asset			(22,000)
Purchases of investments	(79,380)	(94,123)	(125,452)
Maturities of investments	32,050	183,743	10,500
Net cash (used in) provided by investing activities	(47,363)	89,613	(138,377)
Financing activities
Proceeds from long-term debt, net of issuance costs		9,670	9,900
Repayment of long-term, debt	(37,366)
Proceeds from issuance of convertible senior notes, net of issuance costs			145,297
Principal payments on the convertible senior notes		(12,174)
Interest make-whole payments on the 2019 Notes	(1,763)	(438)
Proceeds from the exercise of stock options and employee stock purchase program	2,985	569	809
Settlement of restricted stock for tax withholdings	(285)	(68)
Proceeds from the issuance of common stock, net	106,059		105,156
Net cash provided by (used in) financing activities	69,630	(2,441)	261,162
(Decrease) increase in cash, cash equivalents and restricted cash	(11,239)	(51,346)	48,270
Cash, cash equivalents and restricted cash at beginning of period	79,262	130,608	82,338
Cash, cash equivalents and restricted cash at end of period	68,023	79,262	130,608
Supplemental disclosure
Cash paid for interest	5,126	12,424	2,107
Supplemental disclosure of non-cash investing and financing activities
Common stock issuance costs included in accounts payable and accrued expenses	15	15	$ 15
Purchases of property and equipment included in accounts payable and accrued expenses	217
Settlement of restricted stock units for tax withholdings included in accrued expenses	835
Change in fair value of conversion option of Notes on exchange	2,331	13,640
Conversion of 2019 Notes into common stock	$ 57,414	$ 9,517

Nature of business

Nature of business	12 Months Ended
Nature of business	Dec. 31, 2020
Nature of business
Nature of business	1. Nature of business Verastem, Inc. (the Company) is a development-stage biopharmaceutical company committed to the development and commercialization of new medicines to improve the lives of patients diagnosed with cancer. The Company’s pipeline is focused on novel small molecule drugs that inhibit critical signaling pathways in cancer that promote cancer cell survival and tumor growth, particularly RAF/MEK inhibition and FAK inhibition. Note 16. License, collaboration and commercial agreements The consolidated financial statements include the accounts of Verastem Securities Company and Verastem Europe GmbH, wholly-owned subsidiaries of the Company. All financial information presented has been consolidated and includes the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The Company is subject to the risks associated with other life science companies, including, but not limited to, possible failure of preclinical testing or clinical trials, competitors developing new technological innovations, inability to obtain marketing approval of the Company’s product candidates, VS-6766 and defactinib, market acceptance and commercial success of the Company’s product candidates, VS-6766 and defactinib, following receipt of regulatory approval, and, protection of proprietary technology and the continued ability to obtain adequate financing to fund the Company’s future operations. If the Company does not obtain marketing approval and successfully commercialize its product candidates, VS-6766 and defactinib, following regulatory approval, it will be unable to generate product revenue or achieve profitability and may need to raise additional capital. The Company has historical losses from operations and anticipates that it will continue to incur losses as it continues the research and development of its product candidates. As of December 31, 2020, the Company had cash, cash equivalents, restricted cash, and investments of The Company expects to finance the future development costs of its clinical product portfolio with its existing cash, cash equivalents and short-term investments, through future milestones and royalties received through the Secura APA or through strategic financing opportunities that could include, but are not limited to collaboration agreements, future offerings of its equity, or the incurrence of debt. However, there is no guarantee that any of these strategic or financing opportunities will be executed or executed on favorable terms, and some could be dilutive to existing stockholders. If the Company fails to obtain additional future capital, it may be unable to complete its planned preclinical studies and clinical trials and obtain approval of certain investigational product candidates from the FDA or foreign regulatory authorities.

Significant accounting policies

Significant accounting policies	12 Months Ended
Significant accounting policies	Dec. 31, 2020
Significant accounting policies
Significant accounting policies	2. Significant accounting policies Basis of presentation The accompanying financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) under the assumption that the Company will continue as a going concern for the next twelve months. Accordingly, they do not include any adjustments that might result from the uncertainty related to the Company’s ability to continue as a going concern. Use of estimates The preparation of the Company’s financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. On an ongoing basis, management evaluates its estimates, including estimates related to revenue recognition, including returns, rebates, and other pricing adjustments, accrued and prepaid clinical trial expense and other general accruals and stock-based compensation expense. The Company bases its estimates on historical experience and other market-specific or other relevant assumptions that it believes to be reasonable. Actual results could differ from such estimates. Segment and geographic information Operating segments are defined as components of an enterprise about which separate discrete information is available and regularly reviewed by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating segment, which is the business of developing and commercializing drugs for the treatment of cancer. All material long-lived assets of the Company reside in the United States. Cash, cash equivalents and restricted cash The Company considers all highly liquid investments with an original or remaining maturity of three months or less at the date of purchase to be cash equivalents. Cash equivalents consist of a U.S. Government money market funds and corporate bonds and commercial paper of publicly traded companies. Cash equivalents are reported at fair value. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the consolidated statements of cash flows (in thousands): December 31, 2020 December 31, 2019 Cash and cash equivalents $ 67,782 $ 43,514 Restricted cash 241 35,748 Total cash, cash equivalents and restricted cash $ 68,023 $ 79,262 . Fair value of financial instruments The Company determines the fair value of its financial instruments based upon the fair value hierarchy, which prioritizes valuation inputs based on the observable nature of those inputs. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The hierarchy defines three levels of valuation inputs: Level 1 inputs Quoted prices in active markets for identical assets or liabilities that the Company can access at the measurement date. Level 2 inputs Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 3 inputs Unobservable inputs that reflect the Company’s own assumptions about the assumptions market participants would use in pricing the asset or liability. Items Measured at Fair Value on a Recurring Basis The following table presents information about the Company’s financial instruments that are measured at fair value on a recurring basis (in thousands): December 31, 2020 Description Total Level 1 Level 2 Level 3 Financial assets Cash equivalents $ 65,610 $ 60,611 $ 4,999 $ — Short-term investments $ 73,444 $ — $ 73,444 $ — Long-term investments $ 5,995 $ — $ 5,995 $ — Total financial assets $ 145,049 $ 60,611 $ 84,438 $ — December 31, 2019 Description Total Level 1 Level 2 Level 3 Financial assets Cash equivalents $ 77,176 $ 75,678 $ 1,498 $ — Short-term investments 31,992 — 31,992 — Total financial assets $ 109,168 $ 75,678 $ 33,490 $ — Derivative liability $ 450 — — $ 450 During the year ended December 31, 2019, a derivative liability was recorded as a result of the issuance of 5.00% Convertible Senior Second Lien Notes due 2048 (2019 Notes) (see Note 12 Convertible Senior Notes The following table represents a reconciliation of the derivative liability recorded in connection with the issuance of the 2019 Notes (in thousands): January 1, 2019 $ — Fair value recognized upon issuance of 2019 Notes 247 Fair value adjustment 641 Derivative liability extinguished upon conversion (438) December 31, 2019 $ 450 Fair value adjustment 1,313 Derivative liability extinguished upon conversion (1,763) December 31, 2020 $ — During the year ended December 31, 2020 the derivative liability has been settled upon conversion of all 2019 Notes into shares of common stock (see Note 12. Convertible Senior Notes ). Fair Value of Financial Instruments The fair value of the Company’s long-term debt is determined using a discounted cash flow analysis with current applicable rates for similar instruments as of the consolidated balance sheet dates. The carrying value of the Company’s long-term debt, including the current portion, at December 31, 2020 and 2019, was approximately $0.0 million and $35.1 million, respectively. At December 31, 2020 and 2019, the Company estimates that the fair value of its long-term debt, including the current portion, was approximately The fair value of the 2018 Notes and 2020 Notes (together with the 2019 Notes referred to as the Notes) was approximately $0.3 million and $30.0 million, respectively, as of December 31, 2020 which differs from the aggregate carrying value of the Notes of $19.1 million. The fair value of the 2018 Notes and 2019 Notes was approximately $12.5 million and $50.5 million, respectively, as of December 31, 2019 which differs from the aggregate carrying value of the Notes of $68.6 million. The fair value of the Notes is influenced by the Company’s stock price, stock price volatility, and current market yields. The fair value of the Notes was determined using Level 3 inputs. Investments Investments and cash equivalents consist of investments in a U.S. Government money market funds, overnight repurchase agreements collateralized by government agency securities or U.S. Treasury securities, corporate bonds and commercial paper of publicly traded companies that are classified as available-for-sale pursuant to Accounting Standards Codification (ASC) Topic 320, Investments—Debt and Equity Securities . The Company classifies investments available to fund current operations as current assets on its consolidated balance sheets. Investments are carried at fair value with unrealized gains and losses included as a component of accumulated other comprehensive income (loss), which is a separate component of stockholders’ equity, until such gains and losses are realized. The fair value of these securities is based on quoted prices for identical or similar assets. If a decline in the fair value is considered other-than-temporary, based on available evidence, the unrealized loss is transferred from other comprehensive loss to the consolidated statements of operations and comprehensive loss. The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. To determine whether an impairment is other-than-temporary, the Company considers the intent to sell, or whether it is more likely than not that the Company will be required to sell, the investment before recovery of the investment’s 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 year end. Realized gains and losses are determined using the specific identification method and are included in interest income in the consolidated statements of operations and comprehensive loss. There were no realized gains or losses on investments for the years ended December 31, 2020, 2019 or 2018 There were one debt security and two debt securities in an unrealized loss position as of December 31, 2020 and December 31, 2019, respectively. None of these investments had been in an unrealized loss position for more than 12 months as of December 31, 2020 or December 31, 2019, respectively. The fair value of these securities as of December 31, 2020 and December 31, 2019 was $6.0 million and $5.8 million, respectively, and the aggregate unrealized loss was immaterial. The Company considered the decline in the market value for these securities to be primarily attributable to current economic conditions. As it was not more likely than not that the Company would be required to sell these securities before the recovery of their amortized cost basis, which may be at maturity, the Company did not consider these investments to be other-than-temporarily impaired as of December 31, 2020 and December 31, 2019, respectively. Cash, cash equivalents, restricted cash and investments consist of the following (in thousands): December 31, 2020 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cash, cash equivalents & restricted cash: Cash and money market accounts $ 63,024 $ — $ — $ 63,024 Corporate bonds, agency bonds and commercial paper (due within 90 days ) 4,998 1 — 4,999 Total cash, cash equivalents & restricted cash: $ 68,022 $ 1 $ — $ 68,023 Investments: Corporate bonds, agency bonds and commercial paper (due within 1 year ) $ 73,389 $ 55 $ — $ 73,444 Corporate bonds, agency bonds and commercial paper (due between 1 and 5 years ) 5,998 — (3) 5,995 Total investments $ 79,387 $ 55 $ (3) $ 79,439 Total cash, cash equivalents, restricted cash and investments $ 147,409 $ 56 $ (3) $ 147,462 December 31, 2019 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cash, cash equivalents & restricted cash: Cash and money market accounts $ 77,764 $ — $ — $ 77,764 Corporate bonds, agency bonds and commercial paper (due within 90 days ) 1,498 $ — $ — $ 1,498 Total cash, cash equivalents & restricted cash: $ 79,262 $ — $ — $ 79,262 Investments: Corporate bonds and commercial paper (due within 1 year ) $ 31,979 $ 14 $ — $ 31,993 Total investments $ 31,979 $ 14 $ — $ 31,993 Total cash, cash equivalents, restricted cash and investments $ 111,241 $ 14 $ — $ 111,255 Concentrations of credit risk and off-balance sheet risk Cash and cash equivalents, investments, and trade accounts receivable are financial instruments that potentially subject the Company to concentrations of credit risk. The Company mitigates this risk by maintaining its cash and cash equivalents and investments with high quality, accredited financial institutions. The management of the Company’s investments is not discretionary on the part of these financial institutions. As of December 31, 2020, the Company’s cash, cash equivalents and investments were deposited at three financial institutions and it has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements. As of December 31, 2020 and 2019, there were two customers, that cumulatively made up more than 50% of the Company’s trade accounts receivable balance. The Company assesses the creditworthiness of all its customers and sets and reassesses customer credit limits to ensure collectability of any trade accounts receivable balances are assured. For the year ended December 31, 2020 and 2019, four customers, individually accounted for greater than 10% of the Company’s total product revenue, net and license and collaboration revenue. Property and equipment Property and equipment consist of laboratory equipment, office furniture, computer equipment and leasehold improvements. Expenditures for repairs and maintenance are recorded to expense as incurred, whereas major betterments are capitalized as additions to property and equipment. Depreciation and amortization are calculated using the straight-line method over the following estimated useful lives of the assets: Laboratory equipment 5 years Furniture 5 years Computer equipment 3 years Leasehold improvements Lesser of useful life or life of lease Upon retirement or sale, the cost of the disposed asset and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is recognized. The Company reviews its long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying value of assets may not be recoverable. Recoverability is measured by comparison of the asset’s book value 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 through December 31, 2020. Other assets Other assets primarily consisted of prepayments made to contract research organizations (CROs). As of December 31, 2020 and 2019, other assets were primarily comprised of approximately $0.0 million and $0.8 million respectively, of prepaid CRO expenses that the Company assumed and paid to Infinity pursuant to the license agreement between the Company and Infinity. As part of the sale of COPIKTRA to Secura, the prepaid balance was transferred to Secura and included in cost of sales - sale of COPIKTRA license and related assets in the statement of operations and comprehensive loss for the year ended December 31, 2020. Research and development costs The Company expenses research and development costs to operations as incurred. Research and development expenses consist of: ● employee-related expenses, including salaries, benefits, travel and stock-based compensation expense; ● external research and development expenses incurred under arrangements with third parties, such as CROs, clinical trial sites, manufacturing organizations and consultants, including the scientific advisory board; ● license fees; ● facilities, depreciation and other expenses, which include direct and allocated expenses for rent and maintenance of facilities, depreciation of equipment, and laboratory supplies; and ● costs associated with COPIKTRA prior to the Company concluding that regulatory approval is probable and that its net realizable value is recoverable. Costs for certain development activities, such as clinical trial expenses, are recognized based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations, and information provided to the Company by its vendor on their actual costs incurred or level of effort expended. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected on the consolidated balance sheets as prepaid expenses and other current assets or accrued expenses. Stock-based compensation The Company recognizes stock-based compensation expense for stock options, and restricted stock units (RSUs) issued to employees and directors based on the grant date fair value of the awards on a straight- line basis over the requisite service period, which typically is the vest period. The Company recognized stock-based compensation for shares issued to employees under the Company’s employee stock purchase plan (ESPP) plan Historically, the Company recorded stock line basis over the vesting period. Effective January 1, 2019, the Company recognizes stock-based compensation expense for stock options and RSUs issued to non-employees based on the grant date fair value of the awards on the straight-line basis over the requisite service period. Awards subject to performance-based vesting requirements are expensed utilizing an accelerated attribution model if achievement of the performance criteria is determined to be probable. The Company accounts for forfeitures as they occur. The grant date fair value of stock options is estimated using the Black- Scholes option pricing model that takes into account the fair value of its common stock, the exercise price, the expected life of the option, the expected volatility of its common stock, expected dividends on its common stock, and the risk-free interest rate over the expected life of the option. The Company applies the simplified method described in the Securities and Exchange Commission (SEC) Staff Accounting Bulletin (SAB) Topic 14.D.2 to calculate the expected term as it does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term for options granted to employees. The expected term is applied to the stock option grant group as a whole, as the Company does not expect substantially different exercise or post-vesting termination behavior among its population. The Company has not paid and do not anticipate paying cash dividends on the Company’s shares of common stock; therefore, the expected dividend yield is assumed to be zero. The computation of expected volatility is based on the historical volatility of the Company’s common stock. The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected term of the stock options. The Company issues shares under the Company’s employee stock purchase plan (ESPP) to employees. Stock-based compensation expense for discounted purchases under the ESPP is measured using the Black-Scholes model to compute the fair value of the lookback provision plus the purchase discount and is recognized as compensation expense over the offering period . Leases Leases At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease based on the unique facts and circumstances within the arrangement. A lease is identified where an arrangement conveys the right to control the use of identified property, plant, and equipment for a period of time in exchange for consideration. Leases which are identified within the scope of ASC 842 and which have a term greater than one year are recognized on the Company’s consolidated balance sheets as right-of-use assets, lease liabilities and, if applicable, long-term lease liabilities. The Company has elected not to recognize leases with terms of one year or less on its consolidated balance sheets. Operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected remaining lease term. However, certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. The interest rate implicit in lease contracts is typically not readily determinable. As a result, the Company utilizes its incremental borrowing rates to calculate the present value of lease payments. Incremental borrowing rates are the rates the Company incurs to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. In accordance with ASC 842, components of a lease are split into three categories: lease components (e.g., land, building, etc.), non-lease components (e.g., common area maintenance, maintenance, consumables, etc.), and non-components (e.g., property taxes, insurance, etc.). The fixed and in-substance fixed contract consideration (including any related to non-components) must be allocated based on fair values to the lease components and non-lease components. Although separation of lease and non-lease components is required, certain practical expedients are available. Entities may elect the practical expedient to not separate lease and non-lease components. Rather, they would account for each lease component and the related non-lease component together as a single component. The Company has elected to account for the lease and non-lease components of each of its operating leases as a single lease component and allocate all of the contract consideration to the lease component only. The lease component results in an operating right-of-use asset being recorded on the consolidated balance sheets and amortized on a straight-line basis as lease expense. Revenue Recognition Revenue from Contracts with Customers Product Revenue, Net Product Revenue, Net – The Company recognized revenue on sales of COPIKTRA when a customer obtains control of the product, which occurs at a point in time (typically upon delivery). Product revenues are recorded at the wholesale acquisition costs, net of applicable reserves for variable consideration. Components of variable consideration include trade discounts and allowances, Third-Party Payer chargebacks and discounts, government rebates, other incentives, such as voluntary co-pay assistance, product returns, and other allowances that are offered within contracts between the Company and customers, payors, and other indirect customers relating to the Company’s sale of COPIKTRA. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and are classified as reductions of accounts receivable or a current liability. These estimates take into consideration a range of possible outcomes based upon relevant factors such as customer contract terms, information received from third parties regarding the anticipated payor mix for COPIKTRA, known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled with respect to sales made. The amount of variable consideration which is included in the transaction price may be constrained and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under contracts will not occur in a future period. The Company’s analyses contemplate the application of the constraint in accordance with ASC 606. For the years ended December 31, 2020, 2019 and 2018, the Company determined a material reversal of revenue would not occur in a future period for the estimates detailed below and, therefore, the transaction price was not reduced further. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known. Trade Discounts and Allowances: The Company generally provided customers with invoice discounts on sales of COPIKTRA for prompt payment, which are explicitly stated in the Company’s contracts and are recorded as a reduction of revenue in the period the related product revenue is recognized. In addition, the Company compensated its specialty distributor customers for sales order management, data, and distribution services. The Company has determined such services are not distinct from the Company’s sale of COPIKTRA to the specialty distributor customers and, therefore, these payments have also been recorded as a reduction of revenue within the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020, 2019 and 2018. Third-Party Payer Chargebacks, Discounts and Fees: The Company executed contracts with Third-Party Payers which allowed for eligible purchases of COPIKTRA at prices lower than the wholesale acquisition cost charged to customers who directly purchase the product from the Company. In some cases, customers charged the Company for the difference between what they paid for COPIKTRA and the ultimate selling price to the Third-Party Payers. These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and accounts receivable, net. Chargeback amounts are generally determined at the time of resale to the qualified Third-Party Payer by customers, and the Company generally issues credits for such amounts within a few weeks of the customer’s notification to the Company of the resale. Reserves for chargebacks consist of credits that the Company expects to issue for units that remain in the distribution channel inventories at the end of each reporting period that the Company expects will be sold to Third-Party Payers, and chargebacks that customers have claimed, but for which the Company has not yet issued a credit. In addition, the Company compensated certain Third-Party Payers for administrative services, such as account management and data reporting. These administrative service fees have also been recorded as a reduction of product revenue within the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020, 2019, and 2018. Government Rebates: The Company was subject to discount obligations under state Medicaid programs and Medicare. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses on the consolidated balance sheets. For Medicare, the Company also estimates the number of patients in the prescription drug coverage gap for whom the Company will owe an additional liability under the Medicare Part D program. The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel inventories at the end of each reporting period. Other Incentives: Other incentives which the Company offered include voluntary co-pay assistance programs, which are intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by payors. The calculation of the accrual for co-pay assistance is based on an estimate of claims and the cost per claim that the Company expects to receive for product that has been recognized as revenue but remains in the distribution channel inventories at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as a component of accrued expenses on the consolidated balance sheets. Product Returns: Consistent with industry practice, the Company generally offers customers a limited right of return for product that has been purchased from the Company. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company estimates product return liabilities using available industry data and its own sales information, including its visibility into the inventory remaining in the distribution channel. Subject to certain limitations, the Company’s return policy allows for eligible returns of COPIKTRA for credit under the following circumstances: ● Receipt of damaged product; ● Shipment errors that were a result of an error by the Company; ● Expired product that is returned during the period beginning three months prior to the product’s expiration and ending six months after the expiration date; ● Product subject to a recall; and ● Product that the Company, at its sole discretion, has specified can be returned for credit. If taxes should be collected from customers relating to product sales and remitted to governmental authorities, they will be excluded from product revenue. The Company expenses incremental costs of obtaining a contract when incurred if the expected amortization period of the asset that the Company would have recognized is one year or less. Licenses and Sales of Intellectual Property Exclusive Licenses of Intellectual Property - The Company may enter into collaboration and licensing arrangements for research and development, manufacturing, and commercialization activities with collaboration partners for the development and commercialization of its product candidates, which have components within the scope of ASC 606. The arrangements generally contain multiple elements or deliverables, which may include (i) licenses, or options to obtain licenses, to the Company’s intellectual property or sale of the Company’s license, (ii) research and development activities performed for the collaboration partner, (iii) participation on joint steering committees, and (iv) the manufacturing of commercial, clinical or preclinical material. Payments pursuant to these arrangements typically include non-refundable, upfront payments, milestone payments upon the achievement of significant development events, research and development reimbursements, sales milestones, and royalties on product sales. The amount of variable consideration is constrained until it is probable that the revenue is not at a significant risk of reversal in a future period. The contracts into which the Company enters generally do not include significant financing components. In determining the appropriate amount of revenue to be recognized as it fulfills its obligations under each of its collaboration and license agreements, the Company performs the following steps: (i) identification of the promised goods or services in the contract within the scope of ASC 606; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. As part of the accounting for these arrangements, the Company must use significant judgment to determine: a) the number of performance obligations based on the determination under step (ii) above; b) the transaction price under step (iii) above; c) the stand-alone selling price for each performance obligation identified in the contract for the allocation of transaction price in step (iv) above; and d) the measure of progress in step (v) above. The Company uses judgment to determine whether milestones or other variable consideration, except for royalties on license arrangements, should be included in the transaction price as described further below. If a 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 to the customer and the customer is able to use and benefit from the license. In assessing whether a promise or performance obligation is distinct from the other elements, the Company considers factors such as the research, development, manufacturing and commercialization capabilities of the collaboration partner and the availability of its associated expertise in t

Inventory

Inventory	12 Months Ended
Inventory	Dec. 31, 2020
Inventory
Inventory	3. Inventory December 31, 2020 December 31, 2019 Raw materials $ — $ 955 Work in process — 2,040 Finished goods — 101 Total inventories $ — $ 3,096 Note 16. License, collaboration and commercial agreements

Property and equipment, net

Property and equipment, net	12 Months Ended
Property and equipment, net	Dec. 31, 2020
Property and equipment, net
Property and equipment, net	4. Property and equipment, net Property and equipment and related accumulated depreciation are as follows (in thousands): December 31, December 31, 2020 2019 Leasehold improvements $ 146 $ 146 Furniture and fixtures 1,074 1,074 Computer equipment 665 665 1,885 1,885 Less: accumulated depreciation (1,469) (938) Total property and equipment, net $ 416 $ 947 During the year ended December 31, 2018, an amendment to the Company’s existing office space lease was executed whereby the Company relocated from its previous 15,197 rentable square foot location to an adjacent 27,810 rentable square foot location within the same building. As a result of this amendment, the Company shortened the useful life of the leasehold improvements related to the original location and depreciated this balance through the date which it vacated the original space. Upon vacating the original rentable office space, the Company disposed of the leasehold improvements related to this location. The Company recorded approximately $0.5 million, $0.4 million, and $1.0 million in depreciation expense for the years ended December 31, 2020, 2019 and 2018, respectively .

Intangible assets

Intangible assets	12 Months Ended
Intangible assets	Dec. 31, 2020
Intangible assets
Intangible assets	5. Intangible assets million milestone payment which became payable upon the FDA marketing approval for COPIKTRA on September 24, 2018, pursuant to the amended and restated license agreement with Infinity Pharmaceuticals, Inc. (Infinity). The Company made the milestone payment of On July 2, 2020, the Company’s intangible asset met the Held for Sale criteria and the Company ceased amortization. Pursuant to the Secura APA, discussed further in Note 16. License, collaboration and commercial agreements

Accrued expenses

Accrued expenses	12 Months Ended
Accrued expenses	Dec. 31, 2020
Accrued expenses
Accrued expenses	6. Accrued expenses Accrued expenses consist of the following (in thousands): December 31, 2020 December 31, 2019 Compensation and related benefits 5,930 7,399 Research and development expenses 5,176 5,467 Commercialization costs 330 3,028 Interest 236 897 Consulting fees 1,091 1,610 Professional fees 615 573 Other 1,282 391 Total accrued expenses $ 14,660 $ 19,365

Long-term debt

Long-term debt	12 Months Ended
Long-term debt	Dec. 31, 2020
Long-term debt
Long-term debt	7. Long-term debt On March 21, 2017, the Company entered into a term loan facility of up to $25.0 million with Hercules Capital, Inc. (Hercules). The term loan facility is governed by a loan and security agreement, dated March 21, 2017 (the Original Loan Agreement). The Original Loan Agreement was amended on January 4, 2018, March 6, 2018, October 11, 2018, April 23, 2019, and November 14, 2019 (the Amended Loan Agreement) to increase the total borrowing limit under the Original Loan Agreement from up to $25.0 million to up to $75.0 million, pursuant to certain conditions of funding. Per the terms of the Amended Loan Agreement, the Company may borrow up to an aggregate of $75.0 million, of which $35.0 million was outstanding immediately as of April 23, 2019 (Fourth Amendment Date) (Amended Term A Loan) as a result of the existing outstanding principal of term loans of $25.0 million being converted into the Amended Term A Loan, and an additional $10.0 million being drawn on the Fourth Amendment Date. The remaining $40.0 million of borrowing capacity may be drawn in multiple tranches comprised of (i) a term loan in an amount of up to $15.0 million upon the Company generating cumulative net product revenues (as defined in the Amended Loan Agreement) of either (a) $37.5 million on or before April 30, 2020 or (b) $50.0 million on or before June 30, 2020 (Amended Term B Loan), and (ii) a term loan in an amount of up to $25.0 million available through December 31, 2021, subject to Hercules’ approval and certain other conditions specified in the Amended Loan Agreement (the Amended Term C Loan, and together with the Amended Term A Loan and Amended Term B Loan, the Amended Term Loan). The funding conditions for the Amended Term B Loan have not been met and expired on June 30, 2020. Per the Amended Loan Agreement, the Company was required to maintain unrestricted and unencumbered cash in accounts subject to control agreements in favor of Hercules of an aggregate amount greater than or equal to 100% of the outstanding debt obligations under the Amended Term Loan Agreement, unless and until the Company receives of Net Product Revenues (as defined in the Amended Loan Agreement) of at least $20 million on or before December 31, 2020, measured on a trailing six month basis (Initial Net Product Revenue Threshold). The Company recorded a total $35.0 million in restricted cash on the consolidated balance sheet as of December 31, 2019. The Amended Term Loan was scheduled to mature on December 1, 2022 (Amended Term Loan Maturity Date). Each advance accrued interest at a floating per annum rate equal to the greater of (a) 9.75% or (b) the lesser of (i) 12.00% and (ii) the sum of (x) 9.75% plus (y) (A) the prime rate (as defined in the Amended Loan Agreement) minus (B) 5.50% . The Amended Term Loan provided for interest-only payments until April 1, 2021, which could have been extended to December 1, 2021 subject to the Company generating $40.0 million in net product revenue on a trailing six-month basis on or prior to December 31, 2020 provided that no event of default has occurred. The Amended Term Loan was secured by a lien on substantially all of the Company’s assets, other than intellectual property and contains customary covenants and representations, including a liquidity covenant, minimum net revenue covenant, financial reporting covenant and limitations on dividends, indebtedness, collateral, investments, distributions, transfers, mergers or acquisitions, taxes, corporate changes, deposit accounts, and subsidiaries. The Company assessed all terms and features of the Amended Loan Agreement in order to identify any potential embedded features that would require bifurcation or any beneficial conversion features. As part of this analysis, the Company assessed the economic characteristics and risks of the Amended Loan Agreement, including put and call features. The Company determined that all features of the Amended Loan Agreement were clearly and closely associated with a debt host and did not require bifurcation as a derivative liability, or the fair value of the feature was immaterial to the Company's consolidated financial statements. The Company reassesses the features on a quarterly basis to determine if they require separate accounting. There have been no changes to the Company’s original assessment On November 9, 2020, the Company repaid in full all principal, accrued and unpaid interest, fees, and expenses under the Amended Loan Agreement with Hercules in an aggregate amount of $37.4 million (the Payoff Amount). The Payoff Amount includes the principal balance of $35.0 million, final payment fee of $1.8 million, prepayment penalty fee of $0.5 million, and accrued and unpaid interest of $0.1 million. On November 9, 2020 the Amended Loan Agreement was terminated along with Hercules’ commitment to provide funding under any future term loans. All liens on substantially all of the Company’s assets to secure the loans under the Amended Loan Agreement have been terminated and released. The Payoff Amount, excluding accrued interest, exceeded the carrying amount of the Hercules debt on November 9, 2020 by $1.6 million. As a result, the Company recorded a loss on debt extinguishment of $1.6 million included in the statements of operations and comprehensive loss for the year ended December 31, 2020.

Product revenue reserves and al

Product revenue reserves and allowances	12 Months Ended
Product revenue reserves and allowances	Dec. 31, 2020
Product revenue reserves and allowances
Product revenue reserves and allowances	8. Product revenue reserves and allowances As of December 31, 2020, the Company’s sole source of product revenue has been from sales of COPIKTRA in the United States, which it began shipping to customers on September 25, 2018. Third-Party Trade Payer Government discounts chargebacks, rebates and and discounts other allowances and fees incentives Returns Total Beginning Balance at December 31, 2018 $ 29 $ 88 $ 157 $ 2 $ 276 Provision related to sales in the current year 512 1,306 608 74 2,500 Adjustments related to prior period sales — — (76) — (76) Credits and payments made (430) (1,139) (317) — (1,886) Balance at December 31, 2019 $ 111 $ 255 $ 372 $ 76 $ 814 Provision related to sales in the current year 640 1,820 609 307 3,376 Adjustments related to prior period sales — — — — — Credits and payments made (728) (2,075) (914) (352) (4,069) Ending balance at December 31, 2020 $ 23 $ — $ 67 $ 31 $ 121 Trade discounts and Third-Party Payer chargebacks and discounts are recorded as a reduction to accounts receivable, net on the consolidated balance sheets. Trade allowances and Third-Party Payer fees, government rebates, other incentives and returns are recorded as a component of accrued expenses on the consolidated balance sheets.

Leases

Leases	12 Months Ended
Leases	Dec. 31, 2020
Leases
Leases	9. Leases On April 15, 2014, the Company entered into a lease agreement for approximately 15,197 square feet of office and laboratory space in Needham, Massachusetts. The lease term commenced on April 15, 2014 and was scheduled to expire on September 30, 2019. Effective February 15, 2018, the Company amended its lease agreement to relocate within the facility to another location consisting of 27,810 square feet of office space (the Amended Lease Agreement). The Amended Lease Agreement extends the expiration date of the lease from September 2019 through June 2025. Pursuant to the Amended Lease Agreement, the initial annual base rent amount is approximately $660,000, which increases during the lease term to $1.1 million for the last twelve-month period. The Company has accounted for its Needham, Massachusetts office space as an operating lease. The Company’s lease contains an option to renew and extend the lease terms and an option to terminate the lease prior to the expiration date. The Company has not included the lease extension or the termination options within the right-of-use asset and lease liability on the consolidated balance sheets as neither option is reasonably certain to be exercised. The Company’s lease includes variable non-lease components (e.g., common area maintenance, maintenance, consumables, etc.) that are not included in the right-of-use asset and lease liability and are reflected as an expense in the period incurred. The Company does not have any other operating or finance leases. In calculating the present value of future lease payments, the Company has elected to utilize its incremental borrowing rate based on the remaining lease term at the date of adoption of ASC 842. The Company has elected to account for lease components and associated non-lease components as a single lease component and has allocated all of the contract consideration to the lease components only. This will potentially result in the initial and subsequent measurement of the balances of the right-of-use asset and lease liability for leases being greater than if the policy election was not applied. As of December 31, 2020 a right-of-use asset of $2.7 million and lease liability of $3.5 million are reflected on the consolidated balance sheets. The elements of lease expense were as follows (dollar amounts in thousands): Year ended December 31, 2020 2019 Lease Expense Operating lease expense $ 885 $ 885 Total Lease Expense $ 885 $ 885 Other Information - Operating Leases Operating cash flows paid for amounts included in measurement of lease liabilities $ 955 $ 703 December 31, 2020 Other Balance Sheet Information - Operating Leases Weighted average remaining lease term (in years) 4.5 Weighted average discount rate 14.6% Maturity Analysis 2021 1,019 2022 1,039 2023 1,060 2024 1,081 2025 546 Total $ 4,745 Less: Present value discount (1,256) Lease Liability $ 3,489

Common stock

Common stock	12 Months Ended
Common stock	Dec. 31, 2020
Common stock.
Common stock	10. Common stock As of December 31, 2020 and 2019, the Company had reserved the following shares of common stock for the issuance of common stock for vested restricted stock units, the exercise of stock options, employee stock purchase plan and Notes conversions to shares of common stock (in thousands): December 31, 2020 2019 Shares reserved under equity compensation plans 25,114 15,389 Shares reserved for inducement grants 4,058 6,331 Shares reserved for 2018 Notes 42 3,950 Shares reserved for 2019 Notes — 34,796 Shares reserved for 2020 Notes 8,615 — Employee Stock Purchase Plan 1,300 1,658 Total shares reserved 39,129 62,124 Each share of common stock is entitled to one vote. The holders of the common stock are also entitled to receive dividends whenever funds are legally available and when declared by the board of directors. Private Investment in Public Equity (PIPE) At-the-market equity offering programs On March 30, 2017, the Company established an at-the-market equity offering program (ATM) pursuant to which it was able to offer and sell up to $35.0 million of its common stock at then-current market prices from time to time through Cantor, as sales agent. On August 28, 2017, the Company amended its sales agreement with Cantor to increase the maximum aggregate offering price of shares of common stock that can be sold under the ATM to $75.0 million. During the year-ended December 31, 2020, the Company sold 6,769,559 shares under this program for net proceeds of approximately $12.2 million (after deducting commissions and other offering expenses). Through December 31, 2020, the Company has sold a total of 18,287,913 shares under this program for net proceeds of approximately $59.6 million (after deducting commissions and other offering expenses). Equity offering On May 16, 2018, the Company entered into an underwriting agreement with Cantor relating to the underwritten offering of 7,777,778 shares (the Shares) of the Company’s common stock (the Underwriting Agreement). Cantor agreed to purchase the Shares pursuant to the Underwriting Agreement at a price of On June 14, 2018, the Company entered into a purchase agreement with Consonance Capital Master Account L.P. and P Consonance Opportunities Ltd. (collectively, Consonance) relating to the registered offering of 7,166,666 shares of its common stock at a price of $6.00 per share. The aggregate proceeds from Consonance, net of offering costs, were approximately

Stock-based compensation

Stock-based compensation	12 Months Ended
Stock-based compensation	Dec. 31, 2020
Stock-based compensation
Stock-based compensation	11. Stock-based compensation Stock-based compensation expense as reflected in the Company’s consolidated statements of operations and comprehensive loss was as follows (in thousands): Year ended December 31, 2020 2019 2018 Research and development $ 1,935 $ 1,501 $ 2,043 Selling, general and administrative 6,183 7,038 4,628 Total stock-based compensation expense $ 8,118 $ 8,539 $ 6,671 All of the $8.1 million, $8.5 million, and $6.7 million, of stock-based compensation expense recorded during the years ended December 31, 2020, 2019 and 2018, respectively, was recorded to additional paid-in capital. The Company has awards outstanding under two equity compensation plans, the Amended and Restated 2012 Incentive Plan (the Amended 2012 Plan) and the 2010 Equity Incentive Plan (the 2010 Plan), as well as the inducement award program. Terms of stock award agreements, including vesting requirements, are determined by the board of directors, subject to the provisions of the individual plans. To date, most options granted by the Company vest twenty-five percent (25%) one year from vesting start date and six and a quarter percent (6.25%) for each successive three-month period, thereafter (subject to acceleration of vesting in the event of certain change of control transactions) and are exercisable for a period of ten years from the date of grant. 2012 Incentive Plan The 2012 Plan became effective immediately upon the closing of the Company’s IPO in February 2012. Upon effectiveness of the 2012 Plan, the Company ceased making awards under the 2010 Plan. The 2012 Plan initially allowed the Company to grant awards for up to 3,428,571 shares of common stock, plus the number of shares of common stock available for grant under the 2010 Plan as of the effectiveness of the 2012 Plan (which was an additional 30,101 shares), plus that number of shares of common stock related to awards outstanding under the 2010 Plan which terminate by expiration, forfeiture, cancellation or otherwise. The 2012 Plan included an “evergreen provision” that allowed for an annual increase in the number of shares of common stock available for issuance under the 2012 Plan. The annual increase was added on the first day of each year from 2013 through 2018 and was equal to the lesser of 1,285,714 shares of common stock and 4.0% of the number of shares of common stock outstanding, or a lesser amount as determined by the board of directors. On each of January 1, 2018, January 1, 2017 and January 1, 2016, the number of shares available for issuance under the 2012 Plan increased by 1,285,714 under this provision. On December 18, 2018, the shareholders of the Company approved the Amended and Restated 2012 Incentive Plan which increased the maximum number of shares available for issuance under the 2012 Plan to 16,628,425 and eliminated the evergreen provision. On May 19, 2020, the shareholders of the Company approved the Amended and Restated 2012 Incentive Plan which increased the maximum number of shares available for issuance by 13,000,000 shares. Awards under the 2012 Plan may include the following award types: incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock units (RSUs), other stock-based or cash-based awards and any combination of the foregoing. As of December 31, 2020, under the 2012 Plan, the Company has granted stock options for 21,727,798 shares of common stock, of which 8,496,099 have been forfeited and 1,735,524 have been exercised, and granted restricted stock units for 6,371,656 shares of common stock, of which 922,801 have been forfeited and 2,847,038 have vested. The exercise price of each option has been equal to the closing price of a share of the Company’s common stock on the grant date. As of December 31, 2020, 10,947,871 shares remain available for future issuance. Inducement Award Program In December 2014, the Company established an inducement award program (in accordance with Nasdaq Listing Rule 5635(c)(4)) under which it may grant non-statutory stock options to purchase, and RSUs in respect of up to an aggregate of additional shares of common stock under this program. In June and December 2018, the Board of Directors authorized and reserved additional shares of common stock under this program, respectively. In February 2020, the Board of Directors authorized the reduction of have vested. As of December 31, 2020, Stock Options A summary of the Company’s stock option activity and related information for the year ended December 31, 2020 is as follows: Weighted-average Weighted-average remaining Aggregate exercise price per contractual term intrinsic value Shares share (years) (in thousands) Outstanding at December 31, 2019 17,258,524 $ 4.00 7.3 $ 185 Granted 2,291,815 $ 2.11 Exercised (1,498,355) $ 1.72 Forfeited/cancelled (5,361,239) $ 4.05 Outstanding at December 31, 2020 12,690,745 $ 3.90 6.5 $ 3,390 Vested at December 31, 2020 8,053,260 $ 4.70 5.2 $ 2,150 The fair value of each stock option was estimated using a Black-Scholes option-pricing model with the following weighted-average assumptions: Year ended December 31, 2020 2019 2018 Risk-free interest rate 0.60 % 1.98 % 2.65 % Volatility 96 % 87 % 81 % Dividend yield — — — Expected term (years) 6.0 5.9 5.8 The Company recorded stock-based compensation expense associated with employee and non-employee stock options of $4.3 million, $7.1 million, and $5.6 million, for the years ended December 31, 2020, 2019, and 2018, respectively. The weighted-average grant date fair value of options granted in the years ended December 31, 2020, 2019, and 2018 was $1.62, $1.44, and $3.72 per share, respectively. The fair value of options that vested during the years ended December 31, 2020, 2019, and 2018 was At December 31, 2020, there was $7.1 million of total unrecognized compensation cost related to unvested stock options and the Company expects to recognize this cost over a remaining weighted-average period of 2.6 years. Restricted Stock Units (RSUs) The Company awards RSUs to employees under its 2012 Incentive Plan and Inducement Award Program. Each RSU entitles the holder to receive one share of the Company’s common stock when the RSU vests. The RSUs generally vest in either (i) four substantially equal installments on each of the first four anniversaries of the vesting commencement date, or (ii) 100 percent on the first anniversary of the vesting commencement date, subject to the employee’s continued employment with, or service to, the Company on such vesting date. Compensation expense is recognized on a straight-line basis. A summary of RSU activity during the year ended December 31, 2020 is as follows: Shares Weighted-average grant date fair value per share Outstanding at December 31, 2019 678,089 $ 2.36 Granted 4,471,534 $ 1.64 Vested (2,020,782) $ 1.60 Forfeited/cancelled (479,524) $ 2.27 Outstanding at December 31, 2020 2,649,317 $ 1.73 The Company recorded stock-based compensation expense associated with employee and non-employee RSUs of $3.7 million, $1.0 million, and $0.4 million, for the years ended December 31, 2020, 2019, and 2018, respectively. The total fair value of restricted stock units vested during the years ended December 31, 2020, 2019, and 2018 was approximately $3.8 million, $0.3 million, and $0.0 million, respectively. At December 31, 2020, there was $3.8 million of total unrecognized compensation cost related to unvested RSUs and the Company expects to recognize this cost over a remaining weighted-average period of 1.5 years. On March 27, 2020, the Company amended all outstanding stock options and RSUs awards held by employees (including executive officers), other than certain performance-based awards, to provide that, in the event of a change of control, such equity awards currently held by employees that are outstanding and unvested immediately prior to a change of control of the Company will become fully vested and, if applicable, exercisable immediately prior to, and subject to the consummation of, such change of control. The amendment was implemented to provide assurance to the Company’s existing employees and not in response to any change of control offer for the Company. The modification affected 93 employees and will result in incremental stock compensation expense of $0.2 million to be recognized over the remaining requisite service period for each award. The modification resulted in incremental stock compensation expense of $0.1 million recognized in the year ended December 31, 2020. The Company modified all unvested equity awards held by employees included in the August 2020 Restructuring discussed in Note. 17 Restructurings Employee stock purchase plan At the Special Meeting of Stockholders, held on December 18, 2018, the stockholders approved the 2018 Employee Stock Purchase Plan (2018 ESPP). On June 21, 2019, the board of directors of the Company amended and restated the 2018 ESPP, to account for certain non-material changes to the plan’s administration (the Amended and Restated 2018 ESPP). The Amended and Restated 2018 ESPP provides eligible employees with the opportunity, through regular payroll deductions, to purchase shares of the Company’s common stock at 85% of the lesser of the fair market value of the common stock (a) on the date the option is granted, which is the first day of the purchase period, and (b) on the exercise date, which is the last business day of the purchase period. The Amended and Restated 2018 ESPP generally allows for two six-month purchase periods per year beginning in January and July, or such other periods as determined by the compensation committee of the Company’s board of directors. The Company has reserved 2,000,000 shares of common stock for the administration of the Amended and Restated 2018 ESPP. The fair value of shares expected to be purchased under the Amended and Restated 2018 ESPP was calculated using the Black-Scholes model with the following weighted-average assumptions: Year ended December 31, 2020 2019 Risk-free interest rate 1.04 % 2.26 % Volatility 109 % 88 % Dividend yield — — Expected term (years) 0.5 0.5

Convertible Senior Notes

Convertible Senior Notes	12 Months Ended
Convertible Senior Notes	Dec. 31, 2020
Convertible Senior Notes
Convertible Senior Notes	12. Convertible Senior Notes 2018 Notes On October 17, 2018, the Company closed a registered direct public offering of $150.0 million aggregate principal amount of the Company’s 5.00% Convertible Senior Notes due 2048 (the 2018 Notes), for net proceeds of approximately $145.3 million. The 2018 Notes are governed by the terms of a base indenture for senior debt securities (the Base Indenture), as supplemented by the first supplemental indenture thereto (the Supplemental Indenture and together with the 2018 Base Indenture, the 2018 Indenture), each dated October 17, 2018, by and between the Company and Wilmington Trust, National Association, (Wilmington) as trustee. The 2018 Notes are senior unsecured obligations of the Company and bear interest at a rate of The 2018 Notes are convertible into shares of the Company’s common stock, par value $0.0001 per share, together, if applicable, with cash in lieu of any fractional share, at an initial conversion rate of 139.5771 shares of common stock per $1,000 principal amount of the Notes, which corresponds to an initial conversion price of approximately $7.16 per share of common stock and represents a conversion premium of approximately 15.0% above the last reported sale price of the common stock of $6.23 per share on October 11, 2018. Upon conversion, converting noteholders will be entitled to receive accrued interest on their converted 2018 Notes. To the extent the Company has insufficient authorized but unissued shares to settle conversions in shares of common stock, the Company would be required to settle the deficiency in cash. The Company will have the right, exercisable at its option, to cause all Notes then outstanding to be converted automatically if the “Daily VWAP” (as defined in the 2018 Indenture) per share of the Company’s common stock equals or exceeds 130% of the conversion price on each of at least 20 VWAP Trading Days (as defined in the 2018 Indenture), whether or not consecutive, during any 30 consecutive VWAP Trading Day period commencing on or after the date the Company first issued the 2018 Notes. The conversion rate is subject to adjustment from time to time upon the occurrence of certain events, including, but not limited to, the issuance of stock dividends and payment of cash dividends, but will not be adjusted for any accrued and unpaid interest. Prior to November 1, 2022, the Company will not have the right to redeem the 2018 Notes. On or after November 1, 2022, the Company may elect to redeem the 2018 Notes, in whole or in part, at a cash redemption price equal to the principal amount of the 2018 Notes to be redeemed, plus accrued and unpaid interest, if any. Unless the Company has previously called all outstanding 2018 Notes for redemption, the 2018 Notes will be subject to repurchase by the Company at the holders’ option on each of November 1, 2023, November 1, 2028, November 1, 2033, November 1, 2038 and November 1, 2043 (or, if any such date is not a business day, on the next business day) at a cash repurchase price equal to the principal amount of the 2018 Notes to be repurchased, plus accrued and unpaid interest, if any. If a “Fundamental Change” (as defined in the 2018 Indenture) occurs at any time, subject to certain conditions, holders may require the Company to purchase all or any portion of their 2018 Notes at a purchase price equal to 100% of the principal amount of the 2018 Notes to be purchased, plus accrued and unpaid interest. If a “Fundamental Change” occurs on or before November 1, 2022 and a holder elects to convert its Notes in connection with such change, such holder may be entitled to an increase in the conversion rate in certain circumstances as set forth in the Indenture. The 2018 Notes are the Company’s senior, unsecured obligations and will be senior in right of payment to the Company’s future indebtedness that is expressly subordinated in right of payment to the 2018 Notes; equal in right of payment with the Company’s existing and future indebtedness that is not so subordinated, and effectively subordinated to the Company’s existing and future secured indebtedness, to the extent of the value of the collateral securing such indebtedness. The 2018 Notes are structurally subordinated to all existing and future indebtedness and other liabilities, including trade payables, and (to the extent the Company is not a holder thereof) preferred equity, if any, of the Company’s subsidiaries. The Company assessed all terms and features of the 2018 Notes in order to identify any potential embedded features that would require bifurcation. As part of this analysis, the Company assessed the economic characteristics and risks of the 2018 Notes, including the conversion, put and call features. Per the terms of the 2018 Indenture, upon conversion of the 2018 Notes, a portion of the principal may be settled in cash until the date upon which the Company’s stockholders approve an increase in the number of authorized shares of common stock, or the Authorized Share Effective Date, as defined. In consideration of this provision, the Company concluded the conversion feature required bifurcation as a derivative. The fair value of the conversion feature derivative was determined based on the difference between the fair value of the 2018 Notes with the conversion option and the fair value of the 2018 Notes without the conversion option. The Company determined that the fair value of the derivative upon issuance of the 2018 Notes was October 17, 2018 On December 18, 2018, the Authorized Share Effective Date was achieved as the Company’s stockholders approved an increase in the number of authorized shares of Common Stock. Following this approval, no portion of the 2018 Notes are settleable in cash upon conversion. As such, the Company determined that the conversion feature no longer met the definition of a derivative following the increase in the number of authorized shares of common stock. As of December 18, 2018, the Company determined the fair value of the conversion feature was million. The Company recorded the change in the fair value of the conversion feature for the period from October 17, 2018 to December 18, 2018 of million as other income on the consolidated statements of operations and comprehensive loss. As of December 18, 2018, the fair value of the conversion option was reclassified to additional paid-in capital on the consolidated balance sheets as it qualified for a scope exception from derivative accounting. Accordingly, the conversion feature will no longer be measured at fair value on the Company’s financial statements. The Company determined that all other features of the 2018 Notes were clearly and closely associated with a debt host and did not require bifurcation as a derivative liability, or the fair value of the feature was immaterial to the Company's consolidated financial statements. The Company reassesses the features on a quarterly basis to determine if they require separate accounting. There have been no changes to the Company’s original assessment through December 31, 2020. 2019 Notes On November 14, 2019 and December 23, 2019, the Company entered into privately negotiated agreements to exchange approximately $114.3 million and $7.4 million, respectively, aggregate principal amount of the 2018 Notes for (i) approximately $62.9 million and $4.0 million, respectively, aggregate principal amount of 2019 Notes (ii) an aggregate of approximately $11.4 million and $0.7 million in 2018 Notes principal repayment and (iii) accrued interest on the 2018 Notes through November 14, 2019 and December 23, 2019, respectively. The 2019 Notes are governed by the terms of an indenture (the 2019 Indenture). The 2019 Notes are senior secured obligations of the Company and bear interest at The Company determined 2019 Notes exchange met the definition of a troubled debt restructuring under ASC 470-60, Troubled Debt Restructurings by Debtors The 2019 Notes are convertible into shares of the Company’s common stock, par value $0.0001 per share, together, if applicable, with cash in lieu of any fractional share, at an initial conversion rate of 606.0606 shares of common stock per $1,000 principal amount of the 2019 Notes, which corresponds to an initial conversion price of approximately $1.65 per share of common stock and represents a conversion premium of approximately 52.8% above the last reported sale price of the Company’s common stock of $1.08 per share on November 11, 2019. The Company will have the right, exercisable at the Company’s option, to cause all 2019 Notes then outstanding to be converted automatically if the “Daily VWAP” (as defined in the 2019 Indenture) per share of the Company’s common stock equals or exceeds 121% of the conversion price on each of at least 20 VWAP Trading Days, whether or not consecutive, during any 30 consecutive VWAP Trading Day period commencing on or after the date the Company first issued the 2019 Notes. (Company’s Mandatory Conversion Option). Upon conversion, converting noteholders will be entitled to receive accrued interest on their converted 2019 Notes. In addition, if the 2019 Notes are converted with a conversion date that is on or prior to November 1, 2020, other than in connection with the Company’s exercise of the Company’s Mandatory Conversion Option then the consideration due upon any such conversion will also include a cash interest make-whole payment for all future scheduled interest payments on the converted 2019 Notes through November 1, 2020 (2019 Notes Interest Make-Whole Provision). The conversion rate is subject to adjustment from time to time upon the occurrence of certain events, including, but not limited to, the issuance of stock dividends and payment of cash dividends, but will not be adjusted for any accrued and unpaid interest. The Company assessed all terms and features of the 2019 Notes in order to identify any potential embedded features that would require bifurcation. As part of this analysis, the Company assessed the economic characteristics and risks of the 2019 Notes, including the conversion, put and call features. In consideration of the 2019 Notes Interest Make-Whole Provision, the Company concluded the provision required bifurcation as a derivative. The fair value of the 2019 Interest Make-Whole Provision was determined using a Monte Carlo model. It was determined that the fair value of the derivative upon the November 14, 2019 and December 23, 2019 issuance of the 2019 Notes was debt During the first three months of the year ended December 31, 2020, 2019 Note holders converted $57.4 million aggregate principal of 2019 Notes in exchange for 34,796,350 shares of common stock and $1.8 million of cash for the 2019 Note Interest Make-Whole Provision. The Company recorded $1.3 million for the year ended December 31, 2020, as other expense for the change in fair value of the 2019 Notes Interest Make-Whole Provision in the consolidated statements of operations and comprehensive loss. The Company determined that all other features of the 2019 Notes were clearly and closely associated with a debt host and did not require bifurcation as a derivative liability, or the fair value of the feature was immaterial to the Company's consolidated financial statements. As of December 31, 2020, all 2019 Notes have converted into shares of common stock.. 2020 Notes On November 6, 2020, the Company entered into a privately negotiated agreement with an investor who is a holder of the Company’s 2018 Notes to exchange approximately $28.0 million aggregate principal amount of 2018 Notes for approximately $28.0 million aggregate principal amount of newly issued 5.00% Convertible Senior Notes due 2048 (the 2020 Notes). The issuance of the 2020 Notes closed on November 13, 2020. The 2020 Notes are governed pursuant to the Base Indenture between the Company and Wilmington dated as of October 17, 2018 as supplemented by the second supplemental indenture thereto dated as of November 13, 2020 (the Supplemental Indenture and together with the Base Indenture, the 2020 Indenture). The Company will have the right, exercisable at its option, to cause all 2020 Notes then outstanding to be converted automatically if the “Daily VWAP” (as defined in the 2020 Indenture) per share of the Company’s common stock equals or exceeds 123.08% of the conversion price on each of at least 20 “VWAP Trading Days” (as defined in the 2020 Indenture), whether or not consecutive, during any 30 consecutive VWAP Trading Day period commencing on or after the date the Company first issued the 2020 Notes. The initial conversion rate for the 2020 Notes is 307.6923 shares of the Company’s common stock per $1,000 principal amount of the 2020 Notes, which is equivalent to an initial conversion price of approximately $3.25 per share, representing an approximately 153.9% premium to the sale price of $1.28 per share of the Company’s common stock on November 5, 2020, as reported on the Nasdaq Global Market. The conversion rate is subject to adjustment from time to time upon the occurrence of certain events, including, but not limited to, the issuance of stock dividends and payment of cash dividends, but will not be adjusted for any accrued and unpaid interest. Prior to November 1, 2023, the Company will not have the right to redeem the 2020 Notes. On or after November 1, 2023, the Company may elect to redeem the 2020 Notes, in whole or in part, at a cash redemption price equal to the principal amount of the 2020 Notes to be redeemed, plus accrued and unpaid interest, if any. Unless the Company has previously called all outstanding 2020 Notes for redemption, the 2020 Notes will be subject to repurchase by the Company at the holders’ option on each of November 1, 2023, November 1, 2028, November 1, 2033, November 1, 2038 and November 1, 2043 (or, if any such date is not a business day, on the next business day) at a cash repurchase price equal to the principal amount of the 2020 Notes to be repurchased, plus accrued and unpaid interest, if any. If a Fundamental Change (as defined in the 2020 Indenture) occurs at any time, subject to certain conditions, holders may require the Company to purchase all or any portion of their 2020 Notes at a purchase price equal to 100% of the principal amount of the 2020 Notes to be purchased, plus accrued and unpaid interest, if any, to, but excluding, the “Fundamental Change Repurchase Date” (as defined in the 2020 Indenture). If a “Make-Whole Fundamental Change” (as defined in the 2020 Indenture) occurs on or before November 1, 2022 and a holder elects to convert its 2020 Notes in connection with such Make-Whole Fundamental Change, such holder may be entitled to an increase in the conversion rate in certain circumstances as set forth in the 2020 Indenture. Upon conversion of the 2020 Notes, holders will receive a cash payment equal to the accrued and unpaid interest on the converted 2020 Notes. The 2020 Notes are the Company’s senior unsecured obligations and will be senior in right of payment to the Company’s future indebtedness that is expressly subordinated in right of payment to the 2020 Notes, and equal in right of payment with the Company’s existing and future indebtedness that is not so subordinated, and effectively subordinated to the Company’s existing and future indebtedness, to the extent of the value of the collateral securing such indebtedness. The 2020 Notes are structurally subordinated to all existing and future indebtedness and other liabilities, including trade payables, and (to the extent the Company is not a holder thereof) preferred equity, if any, of the Company’s subsidiaries. The Company determined the 2020 Notes exchange met the definition of a debt modification under ASC 470-50, Modifications and Extinguishments The Company determined that all features of the 2020 Notes were clearly and closely associated with a debt host and did not require bifurcation as a derivative liability, or the fair value of the feature was immaterial to the Company's consolidated financial statements. The Company reassesses the features on a quarterly basis to determine if they require separate accounting. There have been no changes to the Company’s original assessment through December 31, 2020. All Notes The Company determined that the expected life of the 2018 Notes and 2020 was equal to the period through November 1, 2023 as this represents the point at which the 2018 Notes and 2020 Notes are initially subject to repurchase by the Company at the option of the holders. Accordingly, the total debt discount, inclusive of the fair value of the embedded conversion feature derivative at issuance and change in fair value of conversion option upon exchange is being amortized using the effective interest method through November 1, 2023. For the year ended December 31, 2020, the Company recognized an aggregate of

Net Loss per share

Net Loss per share	12 Months Ended
Net Loss per share	Dec. 31, 2020
Net Loss per share
Net Loss per Share	13. Net Loss per Share ASC Topic 260, Earnings Per Share, The computation of basic and diluted net loss per share attributable to common stockholders consists of the following: Year Ended December 31, 2020 2019 2018 Numerator Net loss (67,726) (149,209) (72,434) Less: Other income — — (25,556) Add: Interest expense — — 3,071 Adjusted diluted net loss (67,726) (149,209) (94,919) Denominator Weighted average shares outstanding - basic 153,330 74,578 64,962 Effect of dilutive securities: 2018 Notes — — 4,359 Weighted average shares outstanding - diluted 153,330 74,578 69,321 Net loss per share - basic (0.44) (2.00) (1.12) Net loss per share - diluted (0.44) (2.00) (1.37) million is added to the Company’s net loss. As of December 31, 2018, upon conversion of all outstanding 2018 Notes, the Company would be required to issue shares. Under the “if-converted” method, convertible instruments are assumed to have been converted as of the beginning of the period or when issued, if later. Accordingly, the weighted average number of potentially issuable shares upon conversion of the 2018 Notes was determined by weighting the number of shares potentially issuable as of December 31, 2018, The following potentially dilutive securities were excluded from the calculation of diluted net loss per share due to their anti-dilutive effect: Year Ended December 31, 2020 2019 2018 Outstanding stock options 12,690,745 17,258,524 12,522,867 Outstanding restricted stock units 2,649,317 678,089 306,750 2018 Notes 41,873 3,950,032 — 2019 Notes — 34,796,363 — 2020 Notes 8,615,384 — — Employee Stock Purchase Plan 53,372 227,141 — Total potentially dilutive securities 24,050,691 56,910,149 12,829,617

Income Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2020
Income Taxes
Income Taxes	14. Income Taxes As of December 31, 2020, the Company had federal and state NOL carryforwards of approximately $348.5 million and $231.9 million, respectively, which are available to reduce future taxable income. The Company also had federal and state tax credits of $1.6 million and $0.6 million, respectively, which may be used to offset future tax liabilities. The NOL and tax credit carryforwards will expire at various dates through 2037, except for $154.5 million of federal NOL carryforwards which may be carried forward indefinitely. During the year ended December 31, 2020, the Company recorded income tax expense of $0.2 million, which primarily related to state income tax as a result of the sale of COPIKTRA license and related assets to Secura. Refer to Note 16. License, collaboration and commercial agreements For the years ended December 31, 2020, 2019, and 2018 income tax expense consisted of the following (in thousands): Year ended December 31, 2020 2019 2018 Current tax expense: Federal $ — $ — $ — State 194 — — Current income tax expense 194 — — Deferred Federal — — — State — — — Deferred income tax expense — — — Total income tax expense $ 194 $ — $ — A reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations follows: December 31, 2020 2019 Income tax benefit using U.S. federal statutory rate 21.00 % 21.00 % State tax benefit, net of federal benefit (8.55) % 4.26 % Research and development tax credits 2.84 % 1.67 % Cancellation of debt — % (4.76) % Permanent items (0.60) % (1.41) % Change in the valuation allowance 35.09 % (20.33) % NOL and tax credit expiration under Section 382 (52.67) % — % Other 2.60 % (0.43) % (0.29) % — % The principal components of the Company’s deferred tax assets and liabilities are as follows (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 86,665 $ 101,039 Capitalized research and development 1,565 2,230 Research and development credits 2,043 22,944 Stock-based compensation 4,041 4,445 Installment sale 9,981 — Other 888 1,451 Total deferred tax assets 105,183 132,109 Deferred tax liabilities: Debt discount (2,245) (3,702) Total deferred tax liabilities (2,245) (3,702) Net deferred tax asset prior to valuation allowance 102,938 128,407 Valuation allowance (102,938) (128,407) Net deferred tax asset $ — $ — The Company has recorded a valuation allowance against its deferred tax assets at December 31, 2020 and 2019 because the Company’s management believes that it is more likely than not that these assets will not be fully realized. The decrease in the valuation allowance of approximately $25.5 million in the year ended December 31, 2020 primarily relates to the loss of NOL carryforwards and research and development credits due to Section 382 of the Internal Revenue Code and similar provisions under state law discussed in the next paragraph Section 382 of the Internal Revenue Code and similar provisions under state law limit the utilization of U.S. and state NOL carryforwards following certain cumulative changes in the ownership interest of significant stockholders over a three-year period in excess of 50%. Based on the Company’s analysis under Section 382, the Company believes that $41.4 million of its federal NOL carryforwards and $168.0 million of its state NOL carryforwards are limited by Section 382 and similar provisions under state law as of December 31, 2020 and have been written off in the year ended December 31, 2020. Due to limitations under Section 382 the Company believes that its Research & Development (R&D) and Orphan Drug (OD) Credits will be limited as of December 31, 2020. The portion of R&D and OD credits that were determined to be limited by Section 382 have been written off as of December 31, 2020. The remaining unused carryforwards and credits remain available for future periods. Due the Company’s full valuation allowance the write off of NOL carryforwards and R&D and OD credits did not have any impact to the statements of operation and comprehensive loss. The Company’s reserves related to taxes are based on a determination of whether and how much of a tax benefit taken by the Company in its tax filings or positions is more likely than not to be realized following resolution of any potential contingencies present related to the tax benefit. From inception and through December 31, 2020, the Company had no unrecognized tax benefits or related interest

Commitments and contingencies

Commitments and contingencies	12 Months Ended
Commitments and contingencies	Dec. 31, 2020
Commitments and contingencies
Commitments and contingencies	15. Commitments and contingencies The Company has entered into a lease agreement for approximately 27,810 square feet of office space in Needham, Massachusetts. Please refer to Note 9. Leases Pursuant to the terms of various agreements, the Company may be required to pay various development, regulatory and commercial milestones. In addition, if any products related to these agreements are approved for sale, the Company may be required to pay significant royalties on future sales. The payment of these amounts, however, is contingent upon the occurrence of various future events, which have a high degree of uncertainty of occurring.

License, collaboration and comm

License, collaboration and commercial agreements	12 Months Ended
License, collaboration and commercial agreements	Dec. 31, 2020
License, collaboration and commercial agreements
License, collaboration and commercial agreements	16. License, collaboration and commercial agreements Secura Bio, Inc. (Secura) On August 10, 2020, the Company and Secura signed the Secura APA and on September 30, 2020, the transaction closed. Pursuant to the Secura APA, the Company sold to Secura its exclusive worldwide license, including related assets, for the research, development, commercialization, and manufacture in oncology indications of products containing duvelisib. The sale included certain intellectual property related to duvelisib in oncology indications, certain existing duvelisib inventory, claims and rights under certain contracts pertaining to duvelisib. Pursuant to the Secura APA, Secura assumed all operational and financial responsibility for activities that were part of the Company’s duvelisib oncology program, including all commercialization efforts related to duvelisib in the United States and Europe, as well as the Company’s ongoing duvelisib clinical trials. Further, Secura assumed all obligations with existing collaboration partners developing and commercializing duvelisib, which include Yakult Honsha Co., Ltd. (Yakult), CSPC Pharmaceutical Group Limited (CSPC), and Sanofi. Additionally, Secura assumed all royalty payment obligations due under the amended and restated license agreement with Infinity (Infinity License Agreement). Pursuant to the terms of the Secura APA, Secura has paid the Company an up-front payment of $70.0 million in September 2020 and has agreed to pay the Company (i) regulatory milestone payments up to $45.0 million, consisting of a payment of $35.0 million upon receipt of regulatory approval of COPIKTRA in the United States for the treatment of peripheral T-cell lymphoma and a payment of $10.0 million upon receipt of the first regulatory approval for the commercial sale of COPIKTRA in the European Union for the treatment of peripheral T-cell lymphoma, (ii) sales milestone payments of up to $50.0 million, consisting of $10.0 million when total worldwide net sales of COPIKTRA exceed $100.0 million, $15.0 million when total worldwide net sales of COPIKTRA exceed $200.0 million and $25.0 million when total worldwide net sales of COPIKTRA exceed $300.0 million, (iii) low double-digit royalties on the annual aggregate net sales above $100.0 million in the United States, European Union, and the United Kingdom of Great Britain and Northern Ireland and (iv) 50% of all royalty, milestone and sublicense revenue payments payable to Secura under the Company’s existing license agreements with Sanofi, Yakult, and CSPC, and 50% of all royalty and milestone payments payable to Secura under any license or sublicense agreement entered into by Secura in certain jurisdictions. In connection with the Secura APA, the Company and Secura entered into a transition services agreement (Secura TSA). Under the terms of the Secura TSA, the Company will provide certain support functions at Secura’s direction for a term of less than one year from the date of execution, unless earlier terminated or extended according to the terms of the Secura TSA (Secura TSA Services). Secura may cancel the Secura TSA at sole discretion for any or no reason with five days ' notice. Services performed are paid at a mutually agreed upon rate. The Company evaluated the Secura APA and Secura TSA in accordance with ASC 606 as the Company concluded that the counterparty, Secura, is a customer. The Company identified the following performance obligations under the Secura APA and Secura TSA: ● a bundled performance obligation consisting of delivery of the duvelisib global license and intellectual property, certain existing duvelisib inventory, certain duvelisib contracts and clinical trials, certain regulatory approvals, and certain regulatory documentation and books and records (the Bundled Secura Performance Obligation); and ● Secura TSA Services. The Company concluded that the duvelisib global license and intellectual property were not distinct within the context of the contract (i.e. separately identifiable) because the other assets including certain existing duvelisib inventory, certain duvelisib contracts and clinical trials, certain regulatory approval, and certain regulatory documentation and books and records do not have stand-alone value from other duvelisib global license and intellectual property and Secura could not benefit from them without the duvelisib global license and intellectual property. Consistent with the guidance under ASC 606-10-25-16A, the Company disregarded immaterial promised goods and services when determining performance obligations. The Company has determined that the upfront payment of $70.0 million, future potential milestone payments and royalties including from Secura’s sublicensees should be allocated to the delivery of the Bundled Secura Performance Obligation. The Company has the right to consideration for TSA services in an amount that corresponds directly with the value to Secura of the Company’s performance to date. Consideration allocated to the Secura TSA Services will be recognized as such services are provided over the performance period using an output method based on the amount to which the Company has a right to invoice. Future potential milestones and royalties were excluded from the transaction price, as all milestone amounts and royalties were fully constrained under the guidance. As part of the Company’s evaluation of the constraint, the Company considered a number of factors in determining whether there is significant uncertainty associated with the future events that would result in the milestone payments and royalties. Those factors include: the amount of variable consideration is highly susceptible to factors outside of the Company’s influence, the uncertainty about the consideration is not expected to be resolved for a long period of time, with respect to future global royalties the Company considered that there is no history of selling COPIKTRA outside of the United States to be able to forecast results reliably. Future potential milestone payments and royalties were fully constrained as the risk of significant revenue reversal related to these amounts has not yet been resolved. During the year ended December 31, 2020, the Company recognized $70.0 million as sale of COPIKTRA license and related assets revenue related to delivery of the Bundled Secura Performance Obligation and $0.4 million in transition services revenue within the statements of operations and comprehensive loss. The Company recognized approximately $31.2 million of cost of sales – sale of COPIKTRA license and related assets within the statements of operations and comprehensive income (loss) which consisted of $19.2 million, $6.0 million, $5.8 million and $0.2 million for the intangible asset, certain duvelisib inventory, net duvelisib contract prepaid balances and manufacturing equipment, respectively, which were delivered to Secura as part of the sale. Chugai Pharmaceutical Co., Ltd (Chugai) On January 7, 2020, the Company entered into a license agreement with Chugai (the Chugai Agreement) whereby Chugai granted the Company an exclusive worldwide license for the development, commercialization and manufacture of products containing VS-6766, a dual RAF/MEK inhibitor. Under the terms of the Chugai Agreement, the Company received an exclusive right to develop and commercialize products containing VS-6766 at the Company’s own cost and expense. The Company is required to pay Chugai a non-refundable payment of $3.0 million which was paid in February 2020. The Company is further obligated to pay Chugai double-digit royalties on net sales of products containing VS-6766, subject to reduction in certain circumstances. Chugai also obtained opt back rights to develop and commercialize VS-6766 (a) in the European Union, which option may be exercised through the date the Company submits a NDA to the FDA for a product which contains VS-6766 as the sole active pharmaceutical ingredient and (b) in Japan and Taiwan, which option may be exercised through the date the Company receives marketing authorization from the FDA for a product which contains VS-6766 as the sole active pharmaceutical ingredient. As consideration for executing either option, Chugai would have to make a payment to the Company calculated on the Company’s development costs to date. Chugai and the Company have made customary representations and warranties and have agreed to certain customary covenants, including confidentiality and indemnification. Unless earlier terminated, the Chugai Agreement will expire upon the fulfillment of the Company’s royalty obligations to Chugai for the sale of any products containing the VS-6766, which royalty obligations expire on a product-by-product and country-by-country basis, upon the last to occur, in each specific country, of (a) expiration of valid patent claims covering such product or (b) 12 years from the first commercial sale of such product in such country. The Company may terminate the Chugai Agreement upon 180 days ’ written notice. Subject to certain limitations, Chugai may terminate the Chugai Agreement upon written notice if the Company challenges any patent licensed by Chugai to the Company under the Chugai Agreement. Either party may terminate the license agreement in its entirety with 120 days ’ written notice for the other party’s material breach if such party fails to cure the breach. Either party may also terminate the Chugai Agreement in its entirety upon certain insolvency events involving the other party. The Company evaluated the license agreement with Chugai under ASC Topic 805, Business Combinations ) Pfizer Inc. (Pfizer) On July 11, 2012, the Company entered into a license agreement with Pfizer Inc. (Pfizer), under which Pfizer granted the Company worldwide, exclusive rights to research, develop, manufacture and commercialize products containing certain of Pfizer’s inhibitors of focal adhesion kinase (the FAK Products) for all therapeutic, diagnostic and prophylactic uses in humans. The Company is solely responsible, at its expense, for the clinical development of the FAK Products, which is to be conducted in accordance with an agreed upon development plan. The Company is also responsible for all manufacturing and commercialization activities at its own expense. Pfizer is required to provide the Company with an initial quantity of clinical supply of one of the FAK Products for an agreed upon price. Under the agreement, the Company made a one-time cash payment to Pfizer in the amount of $1.5 million and issued 192,012 shares of its common stock. Pfizer is also eligible to receive up to $2.0 million in developmental milestones and up to an additional $125.0 million based on the successful attainment of regulatory and commercial sales milestones. Pfizer is also eligible to receive high single to mid-double-digit royalties on future net sales of the FAK Products. The Company’s royalty obligations with respect to each FAK Product in each country begin on the date of first commercial sale of the FAK Product in that country, and end on the later of 10 years after the date of first commercial sale of the FAK Product in that country or the date of expiration or abandonment of the last claim contained in any issued patent or patent application licensed by Pfizer to the Company that covers the FAK Product in that country. The Company accounted for the license agreement as the licensing of in process research and development with no alternative future use. Infinity Pharmaceuticals, Inc. (Infinity) In November 2016, the Company entered into the Infinity License Agreement with Infinity under which the Company acquired an exclusive worldwide license for the research, development, commercialization, and manufacture of products in oncology indications containing duvelisib. In connection with the license agreement, the Company assumed operational and financial responsibility for certain activities that were part of Infinity’s duvelisib program, including the DUO study for patients with relapsed/refractory CLL, and Infinity maintained a portion of the financial responsibility for the shutdown of certain other clinical studies. The Company was obligated to use diligent efforts to develop and commercialize a product in an oncology indication containing duvelisib. During the term of the Infinity License Agreement, Infinity has agreed not to research, develop, manufacture or commercialize duvelisib in any other indication in humans or animals. Pursuant to the terms of the Infinity License Agreement, the Company was required to make the following payments to Infinity in cash or, at the Company’s election, in whole or in part, in shares of the Company’s common stock: (i) $6.0 million upon the completion of the DUO study if the results of the DUO study met certain pre-specified criteria, which was paid in cash by the Company to Infinity in October 2017 and recorded as research and development expense in the consolidated statements of operations and comprehensive loss, and (ii) $22.0 million upon the approval of a NDA in the United States or an application for marketing authorization with a regulatory authority outside of the United States for a product in an oncology indication containing duvelisib, which was paid in cash by the Company to Infinity in November 2018 and was recorded as an intangible asset in the consolidated balance sheets. The Company was also obligated to pay Infinity royalties on worldwide net sales of any products in an oncology indication containing duvelisib ranging from the mid-single digits to the high single-digits. The royalties will expire on a product-by-product and country-by-country basis until the latest to occur of (i) the last-to-expire patent right covering the applicable product in the applicable country, (ii) the last-to-expire patent right covering the manufacture of the applicable product in the country of manufacture of such product, (iii) the expiration of non-patent regulatory exclusivity in such country and (iv) ten years following the first commercial sale of a product in a country, provided that if royalties on net sales for a product in the United States are payable solely on the basis of non-patent regulatory exclusivity, the applicable royalty on net sales for such product in the United States will be reduced by 50%. The royalties are also subject to reduction by 50% of certain third-party royalty payments or patent litigation damages or settlements which might be required to be paid by the Company if litigation were to arise, with any such reductions capped at 50% of the amounts otherwise payable during the applicable royalty payment period. In addition to the foregoing, the Company was obligated to pay Infinity an additional royalty of 4% on worldwide net sales of any products in an oncology indication containing duvelisib to cover the reimbursement of research and development costs owed by Infinity to Mundipharma International Corporation Limited (MICL) and Purdue Pharmaceutical Products L.P. (Purdue). Once Infinity has fully reimbursed MICL and Purdue, the royalty obligations will be reduced to 1% of net sales in the United States. These trailing MICL royalties are payable until the later to occur of the last-to-expire of specified patent rights and the expiration of non-patent regulatory exclusivities in a country. Each of the above royalty rates is reduced by 50% on a product-by-product and country-by-country basis if the applicable royalty is payable solely on the basis of non-patent regulatory exclusivity. In addition, the trailing MICL royalties are subject to reduction by 50% of certain third-party royalty payments or patent litigation damages or settlements which might be required to be paid by the Company if litigation were to arise, with any such reductions capped at 50% of the amounts otherwise payable during the applicable royalty payment period. On March 5, 2019, Infinity and Healthcare Royalty Partners III, L.P. (HCR) entered into a purchase and sale agreement, in which HCR paid Infinity a $30.0 million upfront payment and is entitled to receive up to $20.0 million in potential milestone payments from Infinity. In exchange HCR has received the right to receive the royalties due to Infinity from us under the license agreement. As a result, the Company paid royalties previously due to Infinity to HCR. The royalties due to MICL and Purdue described above are still paid to Infinity. The Company evaluated the license agreement with Infinity under ASC 805 and concluded that as substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or group of similar assets, the transaction did not meet the requirements to be accounted for as a business combination and therefore was accounted for as an asset acquisition. All consideration to be paid under the license agreement is contingent in nature and will be recognized when the respective contingency is resolved. During the year ended December 31, 2020, 2019, and 2018, the Company recorded royalty expense of $1.3 million, $1.0 million, and $0.1 million, respectively related to the HCR, Infinity, MICL, and Purdue royalty payments, which are included in costs of sales - product within the consolidated statements of operation and comprehensive loss. As discussed above under heading Secura Bio, Inc. (Secura) Sanofi On July 25, 2019, the Company entered into a license and collaboration agreement with Sanofi (the Sanofi Agreement), under which the Company granted exclusive rights to Sanofi to develop and commercialize products containing duvelisib in Russia, the Commonwealth of Independent States (CIS), Turkey, the Middle East and Africa (collectively the “Sanofi Territory”) for the treatment, prevention, palliation or diagnosis of any oncology indication in humans or animals. Under the terms of the Sanofi Agreement, Sanofi received the exclusive right to develop and commercialize products containing duvelisib in the Sanofi Territory under mutually agreed upon development and commercialization plans at Sanofi’s own cost and expense. In addition, Sanofi received certain limited manufacturing rights in the event the Company is unable to manufacture or supply sufficient quantities of duvelisib or products containing duvelisib to Sanofi during the term of the Sanofi Agreement. The Company retained all rights to duvelisib outside the Sanofi Territory, except for those territories previously and exclusively licensed to other partners. Sanofi paid the Company an upfront, non-refundable payment of $5.0 million in August 2019. The Company is also entitled to receive aggregate payments of up to $42.0 million if certain regulatory and commercial milestones are successfully achieved. Sanofi is obligated to pay the Company double-digit royalties on net sales of products containing duvelisib in the Sanofi Territory, subject to reduction in certain circumstances. Unless earlier terminated by either party, the Sanofi Agreement will expire upon the fulfillment of Sanofi’s royalty obligations to the Company for the sale of any products containing duvelisib in the Sanofi Territory, which royalty obligations expire, on a product-by-product and country-by-country basis, upon the last to occur, in each specific country, of (a) expiration of valid patent claims covering such product, (b) expiration of regulatory exclusivity for such product or (c) 10 years from the first commercial sale of such product in such country. Sanofi may terminate the Sanofi Agreement on a product-by-product basis or on a country-by country basis at any time with 180 days ’ written notice. Either party may terminate the Sanofi Agreement in its entirety with 60 days ’ written notice for the other party’s material breach if such party fails to cure the breach. Subject to certain limitations, the Company may terminate the Sanofi Agreement immediately if Sanofi challenges any patent covering a product or compound licensed by the Company to Sanofi under the Sanofi Agreement. The Company also has the right to terminate Sanofi’s rights to products containing duvelisib in any specific country if Sanofi fails to use certain efforts to develop and commercialize products containing duvelisib in such country. Either party may terminate the Sanofi Agreement in its entirety upon certain insolvency events involving the other party. The Company first assessed the Sanofi Agreement under ASC 808 to determine whether the Sanofi Agreement (or part of the Sanofi Agreement) represents a collaborative arrangement based on the respective risks, rewards and activities of the parties. The Company accounts for collaborative arrangements (or elements within the contract that are deemed part of a collaborative arrangement), which represent a collaborative relationship and not a customer relationship, outside the scope of ASC 606. The Company concluded that the Sanofi Agreement (or part of the Sanofi Agreement) does not represent a collaborative arrangement under ASC 808. The Company then considered each component in the Sanofi Agreement to determine if ASC 606 should be applied to those components. Generally, the component in the Sanofi Agreement that falls under potential research and development activities is the development of duvelisib specifically in the Sanofi Territory. For development of duvelisib specifically in the Sanofi Territory, the Company has concluded that Sanofi is a customer with regard to this component in the context of the Sanofi Agreement. As such, the Sanofi Territory component and all related payments are within the scope of ASC 606. The Company determined that there were two material promises associated with the Sanofi territory-specific activities: (i) an exclusive license to develop and commercialize duvelisib in the Sanofi Territory and (ii) the initial technology transfer. The Company determined that the exclusive license and initial technology transfer were not distinct from one another, as the license has limited value without the initial technology transfer. Therefore, the exclusive license and initial technology transfer are combined as a single performance obligation. The Company evaluated the option rights for manufacturing and supply services to determine whether they represent material rights to Sanofi and concluded that the options were not issued at a significant and incremental discount and therefore do not represent material rights. As such, they are not performance obligations at the outset of the arrangement. Based on this assessment, the Company concluded that one performance obligation exists at the outset of the Sanofi Agreement, which is the exclusive license combined with the initial technology transfer. The Company has determined that the upfront payment of $5.0 million constituted the transaction price at the outset of the Sanofi Agreement. Future potential milestone payments were fully constrained as the risk of significant revenue reversal related to these amounts has not yet been resolved. The achievement of the future potential milestones is not within the Company’s control and is subject to certain regulatory approvals and therefore carry significant uncertainty. The Company will reevaluate the likelihood of achieving future milestones at the end of each reporting period. As all performance obligations have been satisfied, if the risk of significant revenue reversal is resolved, any future milestone revenue from the arrangement will be added to the transaction price (and thereby recognized as revenue) in the period the risk is relieved. The Company satisfied the performance obligation upon delivery of the license and initial technology transfer and recognized the upfront payment of $5.0 million as license and collaboration revenue during the year ended December 31, 2019. For the year ended December 31, 2020, the Company recognized $2.5 million of license revenue upon achievement of two development milestones which were paid in the year ended December 31, 2020. As discussed above under heading Secura Bio, Inc. Yakult Honsha Co., Ltd. (Yakult) On June 5, 2018, the Company entered into a license and collaboration agreement (the Yakult Agreement) with Yakult, under which the Company granted exclusive rights to Yakult to develop and commercialize products containing duvelisib in Japan for the treatment, prevention, palliation or diagnosis of all oncology indications in humans or animals. Under the terms of the Yakult Agreement, Yakult received an exclusive right to develop and commercialize products containing duvelisib in Japan under mutually agreed upon development and commercialization plans at its own cost and expense. Yakult also received certain limited manufacturing rights in the event that the Company is unable to manufacture or supply sufficient quantities of duvelisib or products containing duvelisib to Yakult during the term of the Yakult Agreement. The Company retained all rights to duvelisib outside of Japan. Yakult paid the Company an upfront, non-refundable payment of $10.0 million in June 2018. The Company is also entitled to receive aggregate payments of up to $90.0 million if certain development, regulatory and commercial milestones are successfully achieved. Yakult is obligated to pay the Company a double-digit royalty on net sales of products containing duvelisib in Japan, subject to reduction in certain circumstances, and to fund certain global development costs related to worldwide clinical trials conducted by the Company in which Yakult has opted to participate (Global Clinical Trials) on a pro-rata basis. Unless earlier terminated by either party, the Yakult Agreement will expire upon the fulfillment of Yakult’s royalty obligations to the Company for the sale of any products containing duvelisib in Japan, which royalty obligations expire, on a product-by-product basis, upon the last to occur of (a) expiration of valid claims covering such product, (b) expiration of regulatory exclusivity for such product or (c) 10 years from first commercial sale of such product. Yakult may terminate the Yakult Agreement in its entirety at any time with 180 days’ written notice. Either party may terminate the Yakult Agreement in its entirety with 60 days’ written notice for the other party’s material breach if such party fails to cure the breach. The Company may terminate the Yakult Agreement if (i) Yakult fails to use commercially reasonable efforts to develop and commercialize products containing duvelisib in Japan or (ii) Yakult challenges any patent licensed by the Company to Yakult under the Yakult Agreement. Either party may terminate the Yakult Agreement in its entirety upon certain insolvency events involving the other party. The Company first assessed the Yakult Agreement under ASC 808 to determine whether the Yakult Agreement (or part of the Yakult Agreement) represents a collaborative arrangement based on the risks and rewards and activities of the parties pursuant to the Yakult Agreement. The Company accounts for collaborative arrangements (or elements within the contract that are deemed part of a collaborative arrangement), which represent a collaborative relationship and not a customer relationship, outside the scope of ASC 606. For a component of the Yakult Agreement, the Company concluded that both the Company and Yakult are exposed to significant risks while developing duvelisib and ultimately would share in the reward upon successful commercialization of duvelisib. The Company then considered each remaining component in the Yakult Agreement to determine if ASC 606 should be applied to those components. Generally, the components in the Yakult Agreement fall under one of two potential research and development activities: (i) the parties’ joint participation in Global Clinical Trials and (ii) the territory-specific development of duvelisib. For the parties’ participation in the Global Clinical Trials, the Company concluded that the research and development activities and payments related to such activities are not within the scope of ASC 606 as Yakult is not a customer of the Company with regards to these activities in the context of the Yakult Agreement. As such, costs incurred to execute the Global Clinical Trials will be recorded as research and development expense and payments received from Yakult related to such will be recorded as a reduction of research and development expense. For Territory-specific activities, the Company concluded that Yakult is a customer with regard to this component in the context of the Yakult Agreement. As such, the Territory-specific component and all related payments are within the scope of ASC 606. The Company determined that there were two material promises associated with the territory-specific activities: (i) an exclusive license to develop and commercialize duvelisib in the territory and (ii) the initial technology transfer. The Company determined that the exclusive license and initial technology transfer were not distinct from another, as the license has limited value without the initial technology. Therefore, the exclusive license and initial technology transfer are combined as a single performance obligation. The Company evaluated the option rights for manufacturing and supply services to determine whether they represent material rights to Yakult and concluded that the options were not issued at a significant and incremental discount and therefore do not represent material rights. As such, they are not performance obligations at the outset of the arrangement. Based on this assessment, the Company concluded one performance obligation exists at the outset of the Yakult Agreement: the exclusive license combined with the initial technology transfer. The Company determined that the upfront payment of $10.0 million constitutes the transaction price as of the outset of the Yakult Agreement. Future potential milestone payments were fully constrained as the risk of significant revenue reversal related to these amounts has not yet been resolved. The achievement of the future potential milestones is not within the Company’s control and is subject to certain research and development success or regulatory approvals and therefore carry significant uncertainty. The Company will reevaluate the likelihood of achieving future milestones at the end of each reporting period. As all performance obligations have been satisfied, if the risk of significant revenue reversal is resolved, any future milestone revenue from the arrangement will be added to the transaction price (and thereby recognized as revenue) in the period the risk is relieved. For the year ended December 31, 2020 and 2019 there have been no additional milestones achieved under the Yakult Agreement. The Company satisfied the performance obligation upon delivery of the license and initial technology transfer and recognized the upfront payment of $10.0 million as license revenue during year ended December 31, 2018. As discussed above under heading Secura Bio, Inc. (Secura) Secura Bio, Inc. (Secura) CSPC Pharmaceutical Group Limited (CSPC) On July 26, 2018, the Company and CSPC entered into an Exclusivity Agreement which granted CSPC the exclusive right to negotiate a licensing agreement with the Company for duvelisib in China. CSPC paid the Company a non-refundable exclusivity fee of $5.0 million in August 2018 (Exclusivity Fee) which was creditable against any payments agreed to under the terms of a potential definitive license agreement. Subsequently, on September 25, 2018, the Company entered into a license and collaboration agreement with CSPC (the CSPC Agreement), under which the Company granted exclusive rights to CSPC to develop and commercialize products containing duvelisib in the People’s Republic of China (China), Hong Kong, Macau and Taiwan Under the terms of the CSPC Agreement, CSPC received an exclusive right to develop and commercialize products containing duvelisib in the CSPC Territory the CSPC Territory CSPC paid the Company an aggregate upfront, non-refundable payment of $15.0 million, less the previously paid $5.0 million Exclusivity Fee. The Company is also entitled to receive aggregate payments of up to $160.0 million if certain development, regulatory and commercial milestones are successfully achieved. CSPC is obligated to pay the Company a double-digit royalty on net sales of products containing duvelisib in the CSPC Territory Unless earlier terminated by either party, the CSPC Agreement will expire upon the fulfillment of CSPC’s royalty obligations to the Company for the sale of any products containing duvelisib in the CSPC Territ

Restructurings

Restructurings	12 Months Ended
Restructurings	Dec. 31, 2020
Restructurings
Restructurings	17. Restructurings On October 28, 2019, the Company committed to an operational plan to reduce overall operating expenses, including the elimination of approximately 40 positions across the Company and other cost-saving measures (the October 2019 Restructuring). The October 2019 Restructuring was designed to streamline operations, speed execution, and reflect the focused, account-based approach in the field. The Company recorded On February 27, 2020, following further analysis of the Company’s strategy, the Company committed to an operational plan to reduce overall operating expenses, including the elimination of approximately 31 positions across the Company and other cost-saving measures (the February 2020 Restructuring). The February 2020 Restructuring is designed to streamline operations, speed execution of the Company’s clinical development of VS-6766 and defactinib, and reflect a focused, account-based approach in the field. In August 2020, in connection with the duvelisib sale to Secura pursuant to the Secura APA, the Company committed to a strategic restructuring (the August 2020 Restructuring). The restructuring included a workforce reduction of approximately 41 positions primarily in the Company’s commercial operations department. During the year-ended December 31, 2020, the Company recorded an aggregate expense of $4.6 million for the February 2020 Restructuring and August 2020 Restructuring for one-time termination benefits for employee severance, benefits, and related costs. This expense is reflected in the consolidated statements of operation and comprehensive loss as selling general, and administrative expense for $4.1 million, and research and development expense for $0.5 million. The following table summarizes the accrued liabilities activity recorded in connection with the restructurings for the year ended December 31, 2020 (in thousands): Employee severance, benefits and related costs Amounts Charges Amount Adjustments Amounts October 2019 Restructuring 631 — (626) (5) — February 2020 Restructuring — 1,788 (1,812) 24 — August 2020 Restructuring — 2,993 (1,797) (169) 1,027 Total $ 631 $ 4,781 $ (4,235) $ (150) $ 1,027

Employee benefit plan

Employee benefit plan	12 Months Ended
Employee benefit plan	Dec. 31, 2020
Employee benefit plan
Employee benefit plan	18. Employee benefit plan In June 2011, the Company adopted a 401(k) retirement and savings plan (the 401(k) Plan) covering all employees. The 401(k) Plan allows employees to make pre-tax or post-tax contributions up to the maximum allowable amount set by the Internal Revenue Service. Under the 401(k) Plan, the Company may make discretionary contributions as approved by the board of directors. The Company made contributions to the 401(k) Plan of approximately $0.9 million, $1.3 million, and $0.8 million for the years ended December 31, 2020, 2019, and 2018, respectively.

Quarterly financial information

Quarterly financial information (unaudited, in thousands, except per share data)	12 Months Ended
	Dec. 31, 2020
Quarterly financial information (unaudited, in thousands, except per share data)
Quarterly financial information	19. Quarterly financial information (unaudited, in thousands, except per share data) First Quarter Second Quarter Third Quarter Fourth Quarter Ended Ended Ended Ended March 31, June 30, September 30, December 31, 2020 2020 2020 2020 Revenue: Product revenue, net $ 5,034 $ 4,235 $ 5,829 $ 134 License and collaboration revenue 22 72 2,818 — Sale of COPIKTRA license and related assets — — 70,000 — Transition services revenue — — — 372 Total revenue 5,056 4,307 78,647 506 Operating expenses: Cost of sales - product $ 495 $ 392 $ 866 $ 12 Cost of sales - intangible amortization 392 393 8 — Cost of sales - sale of COPIKTRA license and related assets — — 31,187 — Research and development 10,924 9,344 10,955 10,153 Selling, general and administrative 19,604 15,442 20,614 7,095 Total operating expenses 31,415 25,571 63,630 17,260 (Loss) income from operations (26,359) (21,264) 15,017 (16,754) Other income/(expense) (1,313) — — — Interest income 356 122 19 18 Interest expense (10,674) (1,868) (1,898) (1,354) Loss on debt extinguishment — — — (1,580) Net (loss) income before income taxes (37,990) (23,010) 13,138 (19,670) Income tax expense — — — (194) Net (loss) income $ (37,990) $ (23,010) $ 13,138 $ (19,864) Net (loss) income per share —basic $ (0.35) $ (0.14) $ 0.08 $ (0.12) Net (loss) income per share —diluted $ (0.35) $ (0.14) $ 0.08 $ (0.12) Weighted-average number of common shares used in net loss per share —basic and diluted Net (loss) income per share —basic 108,153 165,395 169,510 169,902 Net (loss) income per share —diluted 108,153 165,395 169,760 169,902 First Quarter Second Quarter Third Quarter Fourth Quarter Ended Ended Ended Ended March 31, June 30, September 30, December 31, 2019 2019 2019 2019 Revenue: Product revenue, net $ 1,671 $ 3,019 $ 4,032 $ 3,617 License and collaboration revenue — 117 5,000 — Total revenue 1,671 3,136 9,032 3,617 Operating expenses: Cost of sales - product $ 158 $ 377 $ 371 $ 332 Cost of sales - intangible amortization 392 392 392 393 Research and development 9,758 11,346 12,219 12,455 Selling, general and administrative 26,033 29,298 22,153 23,728 Total operating expenses 36,341 41,413 35,135 36,908 Loss from operations (34,670) (38,277) (26,103) (33,291) Other income — — — (641) Interest income 1,497 1,268 1,005 611 Interest expense (4,929) (5,185) (5,041) (5,453) Net loss $ (38,102) $ (42,194) $ (30,139) $ (38,774) Net loss per share —basic $ (0.52) $ (0.57) $ (0.41) $ (0.51) Net loss per share —diluted $ (0.52) $ (0.57) $ (0.41) $ (0.51) Weighted-average number of common shares used in net loss per share —basic and diluted Net loss per share —basic 73,854 73,877 74,228 76,331 Net loss per share —diluted 73,854 73,877 74,228 76,331

Subsequent events

Subsequent events	12 Months Ended
Subsequent events	Dec. 31, 2020
Subsequent events
Subsequent events	20. Subsequent events The Company reviews all activity subsequent to year end but prior to the issuance of the consolidated financial statements for events that could require disclosure or that could impact the carrying value of assets or liabilities as of the consolidated balance sheet date. The Company is not aware of any material subsequent events.

Significant accounting polici_2

Significant accounting policies (Policies)	12 Months Ended
Significant accounting policies (Policies)	Dec. 31, 2020
Significant accounting policies
Basis of presentation	Basis of presentation The accompanying financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) under the assumption that the Company will continue as a going concern for the next twelve months. Accordingly, they do not include any adjustments that might result from the uncertainty related to the Company’s ability to continue as a going concern.
Use of estimates	Use of estimates The preparation of the Company’s financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. On an ongoing basis, management evaluates its estimates, including estimates related to revenue recognition, including returns, rebates, and other pricing adjustments, accrued and prepaid clinical trial expense and other general accruals and stock-based compensation expense. The Company bases its estimates on historical experience and other market-specific or other relevant assumptions that it believes to be reasonable. Actual results could differ from such estimates.
Segment and geographic information	Segment and geographic information Operating segments are defined as components of an enterprise about which separate discrete information is available and regularly reviewed by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating segment, which is the business of developing and commercializing drugs for the treatment of cancer. All material long-lived assets of the Company reside in the United States.
Cash, cash equivalents and restricted cash	Cash, cash equivalents and restricted cash The Company considers all highly liquid investments with an original or remaining maturity of three months or less at the date of purchase to be cash equivalents. Cash equivalents consist of a U.S. Government money market funds and corporate bonds and commercial paper of publicly traded companies. Cash equivalents are reported at fair value. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the consolidated statements of cash flows (in thousands): December 31, 2020 December 31, 2019 Cash and cash equivalents $ 67,782 $ 43,514 Restricted cash 241 35,748 Total cash, cash equivalents and restricted cash $ 68,023 $ 79,262 .
Fair value of financial instruments	Fair value of financial instruments The Company determines the fair value of its financial instruments based upon the fair value hierarchy, which prioritizes valuation inputs based on the observable nature of those inputs. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The hierarchy defines three levels of valuation inputs: Level 1 inputs Quoted prices in active markets for identical assets or liabilities that the Company can access at the measurement date. Level 2 inputs Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 3 inputs Unobservable inputs that reflect the Company’s own assumptions about the assumptions market participants would use in pricing the asset or liability. Items Measured at Fair Value on a Recurring Basis The following table presents information about the Company’s financial instruments that are measured at fair value on a recurring basis (in thousands): December 31, 2020 Description Total Level 1 Level 2 Level 3 Financial assets Cash equivalents $ 65,610 $ 60,611 $ 4,999 $ — Short-term investments $ 73,444 $ — $ 73,444 $ — Long-term investments $ 5,995 $ — $ 5,995 $ — Total financial assets $ 145,049 $ 60,611 $ 84,438 $ — December 31, 2019 Description Total Level 1 Level 2 Level 3 Financial assets Cash equivalents $ 77,176 $ 75,678 $ 1,498 $ — Short-term investments 31,992 — 31,992 — Total financial assets $ 109,168 $ 75,678 $ 33,490 $ — Derivative liability $ 450 — — $ 450 During the year ended December 31, 2019, a derivative liability was recorded as a result of the issuance of 5.00% Convertible Senior Second Lien Notes due 2048 (2019 Notes) (see Note 12 Convertible Senior Notes The following table represents a reconciliation of the derivative liability recorded in connection with the issuance of the 2019 Notes (in thousands): January 1, 2019 $ — Fair value recognized upon issuance of 2019 Notes 247 Fair value adjustment 641 Derivative liability extinguished upon conversion (438) December 31, 2019 $ 450 Fair value adjustment 1,313 Derivative liability extinguished upon conversion (1,763) December 31, 2020 $ — During the year ended December 31, 2020 the derivative liability has been settled upon conversion of all 2019 Notes into shares of common stock (see Note 12. Convertible Senior Notes ). Fair Value of Financial Instruments The fair value of the Company’s long-term debt is determined using a discounted cash flow analysis with current applicable rates for similar instruments as of the consolidated balance sheet dates. The carrying value of the Company’s long-term debt, including the current portion, at December 31, 2020 and 2019, was approximately $0.0 million and $35.1 million, respectively. At December 31, 2020 and 2019, the Company estimates that the fair value of its long-term debt, including the current portion, was approximately The fair value of the 2018 Notes and 2020 Notes (together with the 2019 Notes referred to as the Notes) was approximately $0.3 million and $30.0 million, respectively, as of December 31, 2020 which differs from the aggregate carrying value of the Notes of $19.1 million. The fair value of the 2018 Notes and 2019 Notes was approximately $12.5 million and $50.5 million, respectively, as of December 31, 2019 which differs from the aggregate carrying value of the Notes of $68.6 million. The fair value of the Notes is influenced by the Company’s stock price, stock price volatility, and current market yields. The fair value of the Notes was determined using Level 3 inputs.
Investments	Investments Investments and cash equivalents consist of investments in a U.S. Government money market funds, overnight repurchase agreements collateralized by government agency securities or U.S. Treasury securities, corporate bonds and commercial paper of publicly traded companies that are classified as available-for-sale pursuant to Accounting Standards Codification (ASC) Topic 320, Investments—Debt and Equity Securities . The Company classifies investments available to fund current operations as current assets on its consolidated balance sheets. Investments are carried at fair value with unrealized gains and losses included as a component of accumulated other comprehensive income (loss), which is a separate component of stockholders’ equity, until such gains and losses are realized. The fair value of these securities is based on quoted prices for identical or similar assets. If a decline in the fair value is considered other-than-temporary, based on available evidence, the unrealized loss is transferred from other comprehensive loss to the consolidated statements of operations and comprehensive loss. The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. To determine whether an impairment is other-than-temporary, the Company considers the intent to sell, or whether it is more likely than not that the Company will be required to sell, the investment before recovery of the investment’s 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 year end. Realized gains and losses are determined using the specific identification method and are included in interest income in the consolidated statements of operations and comprehensive loss. There were no realized gains or losses on investments for the years ended December 31, 2020, 2019 or 2018 There were one debt security and two debt securities in an unrealized loss position as of December 31, 2020 and December 31, 2019, respectively. None of these investments had been in an unrealized loss position for more than 12 months as of December 31, 2020 or December 31, 2019, respectively. The fair value of these securities as of December 31, 2020 and December 31, 2019 was $6.0 million and $5.8 million, respectively, and the aggregate unrealized loss was immaterial. The Company considered the decline in the market value for these securities to be primarily attributable to current economic conditions. As it was not more likely than not that the Company would be required to sell these securities before the recovery of their amortized cost basis, which may be at maturity, the Company did not consider these investments to be other-than-temporarily impaired as of December 31, 2020 and December 31, 2019, respectively. Cash, cash equivalents, restricted cash and investments consist of the following (in thousands): December 31, 2020 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cash, cash equivalents & restricted cash: Cash and money market accounts $ 63,024 $ — $ — $ 63,024 Corporate bonds, agency bonds and commercial paper (due within 90 days ) 4,998 1 — 4,999 Total cash, cash equivalents & restricted cash: $ 68,022 $ 1 $ — $ 68,023 Investments: Corporate bonds, agency bonds and commercial paper (due within 1 year ) $ 73,389 $ 55 $ — $ 73,444 Corporate bonds, agency bonds and commercial paper (due between 1 and 5 years ) 5,998 — (3) 5,995 Total investments $ 79,387 $ 55 $ (3) $ 79,439 Total cash, cash equivalents, restricted cash and investments $ 147,409 $ 56 $ (3) $ 147,462 December 31, 2019 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cash, cash equivalents & restricted cash: Cash and money market accounts $ 77,764 $ — $ — $ 77,764 Corporate bonds, agency bonds and commercial paper (due within 90 days ) 1,498 $ — $ — $ 1,498 Total cash, cash equivalents & restricted cash: $ 79,262 $ — $ — $ 79,262 Investments: Corporate bonds and commercial paper (due within 1 year ) $ 31,979 $ 14 $ — $ 31,993 Total investments $ 31,979 $ 14 $ — $ 31,993 Total cash, cash equivalents, restricted cash and investments $ 111,241 $ 14 $ — $ 111,255
Concentrations of credit risk and off-balance sheet risk	Concentrations of credit risk and off-balance sheet risk Cash and cash equivalents, investments, and trade accounts receivable are financial instruments that potentially subject the Company to concentrations of credit risk. The Company mitigates this risk by maintaining its cash and cash equivalents and investments with high quality, accredited financial institutions. The management of the Company’s investments is not discretionary on the part of these financial institutions. As of December 31, 2020, the Company’s cash, cash equivalents and investments were deposited at three financial institutions and it has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements. As of December 31, 2020 and 2019, there were two customers, that cumulatively made up more than 50% of the Company’s trade accounts receivable balance. The Company assesses the creditworthiness of all its customers and sets and reassesses customer credit limits to ensure collectability of any trade accounts receivable balances are assured. For the year ended December 31, 2020 and 2019, four customers, individually accounted for greater than 10% of the Company’s total product revenue, net and license and collaboration revenue.
Property and equipment	Property and equipment Property and equipment consist of laboratory equipment, office furniture, computer equipment and leasehold improvements. Expenditures for repairs and maintenance are recorded to expense as incurred, whereas major betterments are capitalized as additions to property and equipment. Depreciation and amortization are calculated using the straight-line method over the following estimated useful lives of the assets: Laboratory equipment 5 years Furniture 5 years Computer equipment 3 years Leasehold improvements Lesser of useful life or life of lease Upon retirement or sale, the cost of the disposed asset and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is recognized. The Company reviews its long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying value of assets may not be recoverable. Recoverability is measured by comparison of the asset’s book value 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 through December 31, 2020.
Other assets	Other assets Other assets primarily consisted of prepayments made to contract research organizations (CROs). As of December 31, 2020 and 2019, other assets were primarily comprised of approximately $0.0 million and $0.8 million respectively, of prepaid CRO expenses that the Company assumed and paid to Infinity pursuant to the license agreement between the Company and Infinity. As part of the sale of COPIKTRA to Secura, the prepaid balance was transferred to Secura and included in cost of sales - sale of COPIKTRA license and related assets in the statement of operations and comprehensive loss for the year ended December 31, 2020.
Research and development costs	Research and development costs The Company expenses research and development costs to operations as incurred. Research and development expenses consist of: ● employee-related expenses, including salaries, benefits, travel and stock-based compensation expense; ● external research and development expenses incurred under arrangements with third parties, such as CROs, clinical trial sites, manufacturing organizations and consultants, including the scientific advisory board; ● license fees; ● facilities, depreciation and other expenses, which include direct and allocated expenses for rent and maintenance of facilities, depreciation of equipment, and laboratory supplies; and ● costs associated with COPIKTRA prior to the Company concluding that regulatory approval is probable and that its net realizable value is recoverable. Costs for certain development activities, such as clinical trial expenses, are recognized based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations, and information provided to the Company by its vendor on their actual costs incurred or level of effort expended. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected on the consolidated balance sheets as prepaid expenses and other current assets or accrued expenses.
Stock-based compensation	Stock-based compensation The Company recognizes stock-based compensation expense for stock options, and restricted stock units (RSUs) issued to employees and directors based on the grant date fair value of the awards on a straight- line basis over the requisite service period, which typically is the vest period. The Company recognized stock-based compensation for shares issued to employees under the Company’s employee stock purchase plan (ESPP) plan Historically, the Company recorded stock line basis over the vesting period. Effective January 1, 2019, the Company recognizes stock-based compensation expense for stock options and RSUs issued to non-employees based on the grant date fair value of the awards on the straight-line basis over the requisite service period. Awards subject to performance-based vesting requirements are expensed utilizing an accelerated attribution model if achievement of the performance criteria is determined to be probable. The Company accounts for forfeitures as they occur. The grant date fair value of stock options is estimated using the Black- Scholes option pricing model that takes into account the fair value of its common stock, the exercise price, the expected life of the option, the expected volatility of its common stock, expected dividends on its common stock, and the risk-free interest rate over the expected life of the option. The Company applies the simplified method described in the Securities and Exchange Commission (SEC) Staff Accounting Bulletin (SAB) Topic 14.D.2 to calculate the expected term as it does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term for options granted to employees. The expected term is applied to the stock option grant group as a whole, as the Company does not expect substantially different exercise or post-vesting termination behavior among its population. The Company has not paid and do not anticipate paying cash dividends on the Company’s shares of common stock; therefore, the expected dividend yield is assumed to be zero. The computation of expected volatility is based on the historical volatility of the Company’s common stock. The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected term of the stock options. The Company issues shares under the Company’s employee stock purchase plan (ESPP) to employees. Stock-based compensation expense for discounted purchases under the ESPP is measured using the Black-Scholes model to compute the fair value of the lookback provision plus the purchase discount and is recognized as compensation expense over the offering period .
Leases	Leases Leases At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease based on the unique facts and circumstances within the arrangement. A lease is identified where an arrangement conveys the right to control the use of identified property, plant, and equipment for a period of time in exchange for consideration. Leases which are identified within the scope of ASC 842 and which have a term greater than one year are recognized on the Company’s consolidated balance sheets as right-of-use assets, lease liabilities and, if applicable, long-term lease liabilities. The Company has elected not to recognize leases with terms of one year or less on its consolidated balance sheets. Operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected remaining lease term. However, certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. The interest rate implicit in lease contracts is typically not readily determinable. As a result, the Company utilizes its incremental borrowing rates to calculate the present value of lease payments. Incremental borrowing rates are the rates the Company incurs to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. In accordance with ASC 842, components of a lease are split into three categories: lease components (e.g., land, building, etc.), non-lease components (e.g., common area maintenance, maintenance, consumables, etc.), and non-components (e.g., property taxes, insurance, etc.). The fixed and in-substance fixed contract consideration (including any related to non-components) must be allocated based on fair values to the lease components and non-lease components. Although separation of lease and non-lease components is required, certain practical expedients are available. Entities may elect the practical expedient to not separate lease and non-lease components. Rather, they would account for each lease component and the related non-lease component together as a single component. The Company has elected to account for the lease and non-lease components of each of its operating leases as a single lease component and allocate all of the contract consideration to the lease component only. The lease component results in an operating right-of-use asset being recorded on the consolidated balance sheets and amortized on a straight-line basis as lease expense.
Revenue Recognition	Revenue Recognition Revenue from Contracts with Customers Product Revenue, Net Product Revenue, Net – The Company recognized revenue on sales of COPIKTRA when a customer obtains control of the product, which occurs at a point in time (typically upon delivery). Product revenues are recorded at the wholesale acquisition costs, net of applicable reserves for variable consideration. Components of variable consideration include trade discounts and allowances, Third-Party Payer chargebacks and discounts, government rebates, other incentives, such as voluntary co-pay assistance, product returns, and other allowances that are offered within contracts between the Company and customers, payors, and other indirect customers relating to the Company’s sale of COPIKTRA. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and are classified as reductions of accounts receivable or a current liability. These estimates take into consideration a range of possible outcomes based upon relevant factors such as customer contract terms, information received from third parties regarding the anticipated payor mix for COPIKTRA, known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled with respect to sales made. The amount of variable consideration which is included in the transaction price may be constrained and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under contracts will not occur in a future period. The Company’s analyses contemplate the application of the constraint in accordance with ASC 606. For the years ended December 31, 2020, 2019 and 2018, the Company determined a material reversal of revenue would not occur in a future period for the estimates detailed below and, therefore, the transaction price was not reduced further. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known. Trade Discounts and Allowances: The Company generally provided customers with invoice discounts on sales of COPIKTRA for prompt payment, which are explicitly stated in the Company’s contracts and are recorded as a reduction of revenue in the period the related product revenue is recognized. In addition, the Company compensated its specialty distributor customers for sales order management, data, and distribution services. The Company has determined such services are not distinct from the Company’s sale of COPIKTRA to the specialty distributor customers and, therefore, these payments have also been recorded as a reduction of revenue within the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020, 2019 and 2018. Third-Party Payer Chargebacks, Discounts and Fees: The Company executed contracts with Third-Party Payers which allowed for eligible purchases of COPIKTRA at prices lower than the wholesale acquisition cost charged to customers who directly purchase the product from the Company. In some cases, customers charged the Company for the difference between what they paid for COPIKTRA and the ultimate selling price to the Third-Party Payers. These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and accounts receivable, net. Chargeback amounts are generally determined at the time of resale to the qualified Third-Party Payer by customers, and the Company generally issues credits for such amounts within a few weeks of the customer’s notification to the Company of the resale. Reserves for chargebacks consist of credits that the Company expects to issue for units that remain in the distribution channel inventories at the end of each reporting period that the Company expects will be sold to Third-Party Payers, and chargebacks that customers have claimed, but for which the Company has not yet issued a credit. In addition, the Company compensated certain Third-Party Payers for administrative services, such as account management and data reporting. These administrative service fees have also been recorded as a reduction of product revenue within the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020, 2019, and 2018. Government Rebates: The Company was subject to discount obligations under state Medicaid programs and Medicare. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses on the consolidated balance sheets. For Medicare, the Company also estimates the number of patients in the prescription drug coverage gap for whom the Company will owe an additional liability under the Medicare Part D program. The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel inventories at the end of each reporting period. Other Incentives: Other incentives which the Company offered include voluntary co-pay assistance programs, which are intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by payors. The calculation of the accrual for co-pay assistance is based on an estimate of claims and the cost per claim that the Company expects to receive for product that has been recognized as revenue but remains in the distribution channel inventories at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as a component of accrued expenses on the consolidated balance sheets. Product Returns: Consistent with industry practice, the Company generally offers customers a limited right of return for product that has been purchased from the Company. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company estimates product return liabilities using available industry data and its own sales information, including its visibility into the inventory remaining in the distribution channel. Subject to certain limitations, the Company’s return policy allows for eligible returns of COPIKTRA for credit under the following circumstances: ● Receipt of damaged product; ● Shipment errors that were a result of an error by the Company; ● Expired product that is returned during the period beginning three months prior to the product’s expiration and ending six months after the expiration date; ● Product subject to a recall; and ● Product that the Company, at its sole discretion, has specified can be returned for credit. If taxes should be collected from customers relating to product sales and remitted to governmental authorities, they will be excluded from product revenue. The Company expenses incremental costs of obtaining a contract when incurred if the expected amortization period of the asset that the Company would have recognized is one year or less. Licenses and Sales of Intellectual Property Exclusive Licenses of Intellectual Property - The Company may enter into collaboration and licensing arrangements for research and development, manufacturing, and commercialization activities with collaboration partners for the development and commercialization of its product candidates, which have components within the scope of ASC 606. The arrangements generally contain multiple elements or deliverables, which may include (i) licenses, or options to obtain licenses, to the Company’s intellectual property or sale of the Company’s license, (ii) research and development activities performed for the collaboration partner, (iii) participation on joint steering committees, and (iv) the manufacturing of commercial, clinical or preclinical material. Payments pursuant to these arrangements typically include non-refundable, upfront payments, milestone payments upon the achievement of significant development events, research and development reimbursements, sales milestones, and royalties on product sales. The amount of variable consideration is constrained until it is probable that the revenue is not at a significant risk of reversal in a future period. The contracts into which the Company enters generally do not include significant financing components. In determining the appropriate amount of revenue to be recognized as it fulfills its obligations under each of its collaboration and license agreements, the Company performs the following steps: (i) identification of the promised goods or services in the contract within the scope of ASC 606; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. As part of the accounting for these arrangements, the Company must use significant judgment to determine: a) the number of performance obligations based on the determination under step (ii) above; b) the transaction price under step (iii) above; c) the stand-alone selling price for each performance obligation identified in the contract for the allocation of transaction price in step (iv) above; and d) the measure of progress in step (v) above. The Company uses judgment to determine whether milestones or other variable consideration, except for royalties on license arrangements, should be included in the transaction price as described further below. If a 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 to the customer and the customer is able to use and benefit from the license. In assessing whether a promise or performance obligation is distinct from the other elements, the Company considers factors such as the research, development, manufacturing and commercialization capabilities of the collaboration partner and the availability of its associated expertise in the general marketplace. In addition, the Company considers whether the collaboration partner can benefit from a promise for its intended purpose without the receipt of the remaining elements, whether the value of the promise is dependent on the unsatisfied promise, whether there are other vendors that could provide the remaining promise, and whether it is separately identifiable from the remaining promise. For licenses that are combined with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time 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 as of progress of 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, is subject to estimates by management and may change over the course of the arrangement. Such a change could have a material impact on the amount of revenue the Company records in future periods. Customer Options: If an arrangement is determined to contain customer options that allow the customer to acquire additional goods or services such as research and development services or manufacturing services, the goods and services underlying the customer options are not considered to be performance obligations at the inception of the arrangement; rather, such goods and services are contingent on exercise of the option, and the associated option fees are not included in the transaction price. The Company evaluates customer options for material rights or options to acquire additional goods or services for free or at a discount. If a customer option is 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 estimated 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. 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. 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. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. 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. Royalties: For license 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 not recognized any royalty revenue resulting from any of its licensing arrangements. For sales of license and intellectual property, that include sale-based royalties, including milestone payments based on a level of sales, the Company evaluates whether the royalties and sales based milestones are considered probable of being achieved and estimates the amount of royalties to include over the contractual term using the expected value method and estimates the sales-based milestones using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated royalty and milestone value is included in the transaction price. Royalties and sales-based milestones for territories for which there is not regulatory approval are not considered probable until such regulatory approval is achieved. The Company evaluates factors such as whether consideration is outside of the Company’s control, timeline for when the uncertainty will be resolved and historical sales of COPIKTRA if applicable. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and amount of royalty revenue to be received 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. Collaborative Arrangements: Contracts are considered to be collaborative arrangements when they satisfy the following criteria defined in ASC Topic 808, Collaborative Arrangements
Accounts Receivable, Net	Accounts Receivable, Net Accounts receivable, net consists of amounts due from customers, net of applicable revenue reserves. Accounts receivable have standard payments that generally require payment within 30 to 90 days . The Company analyzes accounts that are past due for collectability and provides an allowance for receivables when collection becomes doubtful. Given the nature and limited history of collectability of the Company’s accounts receivable, an allowance for doubtful accounts is not deemed necessary at December 31, 2020.
Inventory	Inventory The Company capitalizes inventories manufactured in preparation for initiating sales of a product candidate when the related product candidate is considered to have a high likelihood of regulatory approval and the related costs are expected to be recoverable through sales of the inventories. In determining whether or not to capitalize such inventories, the Company evaluates, among other factors, information regarding the product candidate’s safety and efficacy, the status of regulatory submissions and communications with regulatory authorities and the outlook for commercial sales, including the existence of current or anticipated competitive drugs and the availability of reimbursement. In addition, the Company evaluates risks associated with manufacturing the product candidate, including the ability of the Company’s third-party suppliers to complete the validation batches and the remaining shelf life of the inventories. Costs associated with manufacturing product candidates prior to satisfying the inventory capitalization criteria are charged to research and development expense as incurred. The Company values its inventories at the lower of cost or estimated net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials and manufacturing overhead, on a first-in, first-out basis. The Company performs an assessment of the recoverability of capitalized inventory during each reporting period, and it writes down any excess and obsolete inventories to their estimated realizable value in the period in which the impairment is first identified. Such impairment charges, should they occur, are recorded within cost of sales - product. The determination of whether inventory costs will be realizable requires estimates by management. If actual market conditions are less favorable than projected by management, additional write-downs of inventory may be required which would be recorded as a cost of sales - product in the consolidated statements of operations and comprehensive loss. Shipping and handling costs for product shipments are recorded as incurred in cost of sales - product along with costs associated with manufacturing the product, and any inventory write-downs.
Intangible Assets	Intangible Assets The Company records finite-lived intangible assets related to certain capitalized milestone payments related to commercial products at their fair value. These assets are amortized on a straight-line basis over their remaining useful lives, which are estimated based on the shorter of the remaining underlying patent life or the estimated useful life of the underlying product. The Company assesses its finite-lived intangible assets for impairment if indicators are present or changes in circumstance suggest that impairment may exist. Events that could result in an impairment include the receipt of additional clinical or nonclinical data regarding one of the Company’s drug candidates or a potentially competitive drug candidate, changes in the clinical development program for a drug candidate, or new information regarding potential sales for the drug. If impairment indicators are present or changes in circumstance suggest that impairment may exist, the Company performs a recoverability test by comparing the sum of the estimated undiscounted cash flows of each finite-lived intangible asset to its carrying value on the consolidated balance sheets. If the undiscounted cash flows used in the recoverability test are less than the carrying value, the Company would determine the fair value of the finite-lived intangible asset and recognize an impairment loss if the carrying value of the finite-lived intangible asset exceeds its fair value.
Income taxes	Income taxes The Company accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases using enacted tax rates in effect for the year in which the differences are expected to affect taxable income. Tax benefits are recognized when it is more likely than not that a tax position will be sustained during an audit. Deferred tax assets are reduced by a valuation allowance if current evidence indicates that it is considered more likely than not that these benefits will not be realized. The Company recognizes the tax effects of an uncertain tax position only if it is more likely than not that it will be sustained based solely on its technical merits as of the reporting date and only in an amount more likely than not that it will be sustained upon review by the tax authorities. The Company evaluates uncertain tax positions on a quarterly basis and adjust the liability for changes in facts and circumstances, such as new regulations or interpretations by the taxing authorities, new information obtained during a tax examination, significant amendment to an existing tax law, or resolution of an examination. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will impact the income tax provision in the period in which such determination is made. The resolution of its uncertain income tax positions is dependent on uncontrollable factors such as law changes, new case law, and the willingness of the income tax authorities to settle, including the timing thereof and other factors. Although the Company does not anticipate significant changes to its uncertain income tax positions in the next twelve months, items outside of its control could cause its uncertain income tax positions to change in the future, which would be recorded in its statements of operations. Interest and/or penalties related to income tax matters are recognized as a component of income tax expense. Net operating loss (NOL) and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities and may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant stockholders over a three-year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code, 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 experienced a greater than 50% change in ownership during the year ended December 31, 2020. For more details please Note 14. income taxes.
Net loss per share	Net loss per share Basic net loss per common share is calculated by dividing net loss applicable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per common share is calculated by increasing the denominator by the weighted-average number of additional shares that could have been outstanding from securities convertible into common stock, such as stock options, restricted stock units and warrants (using the “treasury stock” method) and Notes (using the “if-converted” method), unless their effect on net loss per share is antidilutive. The effect of computing diluted net loss per common share was antidilutive for any potentially issuable shares of common stock from the conversion of stock options, restricted stock units and warrants and, as such, have been excluded from the calculation. However, under the “if-converted” method, convertible instruments that are-in-the-money, are assumed to have been converted as of the beginning of the period or when issued, if later. Additionally, the effects of any interest expense and changes in fair value of bifurcated derivatives shall be added back to the numerator of the diluted net loss per share calculation. Refer to Note 13, net loss per share
Recently Issued and/or Adopted Accounting Standards Updates	Recently Issued Accounting Standards Updates In June 2016, the FASB issued Accounting Standard Update (ASU) No. 2016-13, Measurement of Credit Losses on Financial Instruments (ASU 2016-13). ASU 2016-13 will replace the incurred loss impairment methodology under current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. In November 2019, the FASB issued ASU 2019-10, Financial Instruments – Credit Losses (Topic 326), Derivatives (Topic 815), and Leases (Topic 842). This ASU delayed the required adoption for SEC filers that are smaller reporting companies as of their determination on November 15, 2019, until annual and interim periods beginning after December 15, 2022, with early adoption permitted. The Company has determined that as of November 15, 2019, it is a smaller reporting company and has not elected to early adopt this standard. The Company is currently evaluating the impact the adoption of the standard will have on its consolidated financial statements and related disclosures. In December 2019, the FASB issued ASU No 2019-12, Simplifying Accounting for Income Taxes (ASU 2019-12). ASU 2019-12 removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocations, calculating income taxes in interim periods, and adds certain guidance to remove complexity in certain areas. ASU 2019-12 is effective for all entities for annual and interim periods beginning after December 15, 2020. An entity is permitted to early adopt either the entire standard or only the provisions that eliminate or modify requirements. The Company has not elected to early adopt this standard and is currently evaluating the impact the adoption of the standard will have on its consolidated financial statements and related disclosures. In August 2020, the FASB issued No. ASU 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815 – 40) (ASU 2020-06). ASU 2020-06 simplifies the complexity associated with applying U.S. GAAP for certain financial instruments with characteristics of liabilities and equity. More specifically, the amendments focus on the guidance for convertible instruments and derivative scope exception for contracts in an entity’s own equity. The ASU also simplifies the diluted earnings per share (EPS) calculation in certain areas. For smaller reporting companies, ASU 2020-06 is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years. The Company is currently evaluating the impact ASU 2020-06 will have on its consolidated financial statements and related disclosures. Recently Adopted Accounting Standards Updates In November 2018, the Financial Accounting Standards Board (FASB) issued ASU 2018-18, Collaborative Arrangements (ASU 2018-18): Clarifying the Interaction between ASC 808 and ASC 606, which makes targeted improvements for collaborative arrangements to clarify that certain transactions between collaborative arrangement participants should be accounted for as revenue under ASC 606 when the collaborative arrangement participant is a customer in the context of a unit of account, adds unit of account guidance in ASC 808 to align with guidance in ASC 606, and clarifies presentation of certain revenues with a collaborative arrangement participant which are not directly related to a third party. ASU 2018-18 is effective for annual and interim periods beginning after December 15, 2019, with early adoption permitted. This guidance requires entities to adopt on a retrospective basis to the date the Company adopted ASC 606. The Company adopted ASU 2018-18 as of January 1, 2020 on a retrospective basis to January 1, 2018, the date at which the Company adopted ASC 606, and it did not have a material impact on the Company’s consolidated financial statements or disclosures. In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal Use Software: Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract, which 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. ASU 2018-15 is effective for annual and interim periods beginning after December 15, 2019, with early adoption permitted. The Company adopted this standard effective January 1, 2020 on a prospective basis. The adoption of this ASU did not have an effect on the Company’s financial statements or disclosures. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement, which eliminates certain disclosure requirements for fair value measurements for all entities, requires public entities to disclose certain new information and modifies some disclosure requirements. ASU 2018-13 is effective for all entities for annual and interim periods beginning after December 15, 2019. The Company adopted this standard effective January 1, 2020 on a prospective basis. The adoption of this ASU did not have an effect on the Company’s financial statements or disclosures.

Significant accounting polici_3

Significant accounting policies (Tables)	12 Months Ended
Significant accounting policies (Tables)	Dec. 31, 2020
Significant accounting policies
Schedule of reconciliation of cash, cash equivalents and restricted cash	The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the consolidated statements of cash flows (in thousands): December 31, 2020 December 31, 2019 Cash and cash equivalents $ 67,782 $ 43,514 Restricted cash 241 35,748 Total cash, cash equivalents and restricted cash $ 68,023 $ 79,262
Schedule of financial instruments measured at fair value on a recurring basis	The following table presents information about the Company’s financial instruments that are measured at fair value on a recurring basis (in thousands): December 31, 2020 Description Total Level 1 Level 2 Level 3 Financial assets Cash equivalents $ 65,610 $ 60,611 $ 4,999 $ — Short-term investments $ 73,444 $ — $ 73,444 $ — Long-term investments $ 5,995 $ — $ 5,995 $ — Total financial assets $ 145,049 $ 60,611 $ 84,438 $ — December 31, 2019 Description Total Level 1 Level 2 Level 3 Financial assets Cash equivalents $ 77,176 $ 75,678 $ 1,498 $ — Short-term investments 31,992 — 31,992 — Total financial assets $ 109,168 $ 75,678 $ 33,490 $ — Derivative liability $ 450 — — $ 450
Schedule of derivative liability reconciliation	The following table represents a reconciliation of the derivative liability recorded in connection with the issuance of the 2019 Notes (in thousands): January 1, 2019 $ — Fair value recognized upon issuance of 2019 Notes 247 Fair value adjustment 641 Derivative liability extinguished upon conversion (438) December 31, 2019 $ 450 Fair value adjustment 1,313 Derivative liability extinguished upon conversion (1,763) December 31, 2020 $ —
Schedule of cash, cash equivalents and investments	Cash, cash equivalents, restricted cash and investments consist of the following (in thousands): December 31, 2020 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cash, cash equivalents & restricted cash: Cash and money market accounts $ 63,024 $ — $ — $ 63,024 Corporate bonds, agency bonds and commercial paper (due within 90 days ) 4,998 1 — 4,999 Total cash, cash equivalents & restricted cash: $ 68,022 $ 1 $ — $ 68,023 Investments: Corporate bonds, agency bonds and commercial paper (due within 1 year ) $ 73,389 $ 55 $ — $ 73,444 Corporate bonds, agency bonds and commercial paper (due between 1 and 5 years ) 5,998 — (3) 5,995 Total investments $ 79,387 $ 55 $ (3) $ 79,439 Total cash, cash equivalents, restricted cash and investments $ 147,409 $ 56 $ (3) $ 147,462 December 31, 2019 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cash, cash equivalents & restricted cash: Cash and money market accounts $ 77,764 $ — $ — $ 77,764 Corporate bonds, agency bonds and commercial paper (due within 90 days ) 1,498 $ — $ — $ 1,498 Total cash, cash equivalents & restricted cash: $ 79,262 $ — $ — $ 79,262 Investments: Corporate bonds and commercial paper (due within 1 year ) $ 31,979 $ 14 $ — $ 31,993 Total investments $ 31,979 $ 14 $ — $ 31,993 Total cash, cash equivalents, restricted cash and investments $ 111,241 $ 14 $ — $ 111,255
Schedule of estimated useful lives of the assets	Laboratory equipment 5 years Furniture 5 years Computer equipment 3 years Leasehold improvements Lesser of useful life or life of lease

Inventory (Tables)

Inventory (Tables)	12 Months Ended
Inventory (Tables)	Dec. 31, 2020
Inventory
Schedule of inventory	Inventory consists of the following (in thousands): December 31, 2020 December 31, 2019 Raw materials $ — $ 955 Work in process — 2,040 Finished goods — 101 Total inventories $ — $ 3,096

Property and equipment, net (Ta

Property and equipment, net (Tables)	12 Months Ended
Property and equipment, net (Tables)	Dec. 31, 2020
Property and equipment, net
Schedule of property equipment and related accumulated depreciation	Property and equipment and related accumulated depreciation are as follows (in thousands): December 31, December 31, 2020 2019 Leasehold improvements $ 146 $ 146 Furniture and fixtures 1,074 1,074 Computer equipment 665 665 1,885 1,885 Less: accumulated depreciation (1,469) (938) Total property and equipment, net $ 416 $ 947

Accrued expenses (Tables)

Accrued expenses (Tables)	12 Months Ended
Accrued expenses (Tables)	Dec. 31, 2020
Accrued expenses
Schedule of accrued expenses	Accrued expenses consist of the following (in thousands): December 31, 2020 December 31, 2019 Compensation and related benefits 5,930 7,399 Research and development expenses 5,176 5,467 Commercialization costs 330 3,028 Interest 236 897 Consulting fees 1,091 1,610 Professional fees 615 573 Other 1,282 391 Total accrued expenses $ 14,660 $ 19,365

Product revenue reserves and _2

Product revenue reserves and allowances (Tables)	12 Months Ended
Product revenue reserves and allowances (Tables)	Dec. 31, 2020
Product revenue reserves and allowances
Schedule of product revenue allowance and reserve categories	The following table summarizes activity in each of the product revenue allowance and reserve categories for the year ended December 31, 2020 and December 31, 2019 (in thousands): Third-Party Trade Payer Government discounts chargebacks, rebates and and discounts other allowances and fees incentives Returns Total Beginning Balance at December 31, 2018 $ 29 $ 88 $ 157 $ 2 $ 276 Provision related to sales in the current year 512 1,306 608 74 2,500 Adjustments related to prior period sales — — (76) — (76) Credits and payments made (430) (1,139) (317) — (1,886) Balance at December 31, 2019 $ 111 $ 255 $ 372 $ 76 $ 814 Provision related to sales in the current year 640 1,820 609 307 3,376 Adjustments related to prior period sales — — — — — Credits and payments made (728) (2,075) (914) (352) (4,069) Ending balance at December 31, 2020 $ 23 $ — $ 67 $ 31 $ 121

Lease (Tables)

Lease (Tables)	12 Months Ended
Lease (Tables)	Dec. 31, 2020
Leases
Summary of elements of lease expenses	The elements of lease expense were as follows (dollar amounts in thousands): Year ended December 31, 2020 2019 Lease Expense Operating lease expense $ 885 $ 885 Total Lease Expense $ 885 $ 885 Other Information - Operating Leases Operating cash flows paid for amounts included in measurement of lease liabilities $ 955 $ 703 December 31, 2020 Other Balance Sheet Information - Operating Leases Weighted average remaining lease term (in years) 4.5 Weighted average discount rate 14.6% Maturity Analysis 2021 1,019 2022 1,039 2023 1,060 2024 1,081 2025 546 Total $ 4,745 Less: Present value discount (1,256) Lease Liability $ 3,489

Common stock (Tables)

Common stock (Tables)	12 Months Ended
Common stock (Tables)	Dec. 31, 2020
Common stock.
Schedule of shares of common stock reserved for the issuance of common stock for vested restricted stock units and the exercise of stock options	As of December 31, 2020 and 2019, the Company had reserved the following shares of common stock for the issuance of common stock for vested restricted stock units, the exercise of stock options, employee stock purchase plan and Notes conversions to shares of common stock (in thousands): December 31, 2020 2019 Shares reserved under equity compensation plans 25,114 15,389 Shares reserved for inducement grants 4,058 6,331 Shares reserved for 2018 Notes 42 3,950 Shares reserved for 2019 Notes — 34,796 Shares reserved for 2020 Notes 8,615 — Employee Stock Purchase Plan 1,300 1,658 Total shares reserved 39,129 62,124

Stock-based compensation (Table

Stock-based compensation (Tables)	12 Months Ended
Stock-based compensation (Tables)	Dec. 31, 2020
Stock-based compensation
Schedule of stock-based compensation expense as reflected in the Company's consolidated statements of operations and comprehensive loss	Stock-based compensation expense as reflected in the Company’s consolidated statements of operations and comprehensive loss was as follows (in thousands): Year ended December 31, 2020 2019 2018 Research and development $ 1,935 $ 1,501 $ 2,043 Selling, general and administrative 6,183 7,038 4,628 Total stock-based compensation expense $ 8,118 $ 8,539 $ 6,671
Summary of stock option activity and related information	Weighted-average Weighted-average remaining Aggregate exercise price per contractual term intrinsic value Shares share (years) (in thousands) Outstanding at December 31, 2019 17,258,524 $ 4.00 7.3 $ 185 Granted 2,291,815 $ 2.11 Exercised (1,498,355) $ 1.72 Forfeited/cancelled (5,361,239) $ 4.05 Outstanding at December 31, 2020 12,690,745 $ 3.90 6.5 $ 3,390 Vested at December 31, 2020 8,053,260 $ 4.70 5.2 $ 2,150
Schedule of assumptions used to estimate fair value of each stock option on grant date	Year ended December 31, 2020 2019 2018 Risk-free interest rate 0.60 % 1.98 % 2.65 % Volatility 96 % 87 % 81 % Dividend yield — — — Expected term (years) 6.0 5.9 5.8
Schedule of restricted stock units	Shares Weighted-average grant date fair value per share Outstanding at December 31, 2019 678,089 $ 2.36 Granted 4,471,534 $ 1.64 Vested (2,020,782) $ 1.60 Forfeited/cancelled (479,524) $ 2.27 Outstanding at December 31, 2020 2,649,317 $ 1.73
Schedule of assumptions used to estimate fair value of each employee stock purchase plan on grant date	Year ended December 31, 2020 2019 Risk-free interest rate 1.04 % 2.26 % Volatility 109 % 88 % Dividend yield — — Expected term (years) 0.5 0.5

Net Loss per share (Tables)

Net Loss per share (Tables)	12 Months Ended
Net Loss per share (Tables)	Dec. 31, 2020
Net Loss per share
Schedule of computation of basic and diluted net loss per share	Year Ended December 31, 2020 2019 2018 Numerator Net loss (67,726) (149,209) (72,434) Less: Other income — — (25,556) Add: Interest expense — — 3,071 Adjusted diluted net loss (67,726) (149,209) (94,919) Denominator Weighted average shares outstanding - basic 153,330 74,578 64,962 Effect of dilutive securities: 2018 Notes — — 4,359 Weighted average shares outstanding - diluted 153,330 74,578 69,321 Net loss per share - basic (0.44) (2.00) (1.12) Net loss per share - diluted (0.44) (2.00) (1.37)
Schedule of potentially anti-dilutive securities excluded from calculation of diluted net loss per share	Year Ended December 31, 2020 2019 2018 Outstanding stock options 12,690,745 17,258,524 12,522,867 Outstanding restricted stock units 2,649,317 678,089 306,750 2018 Notes 41,873 3,950,032 — 2019 Notes — 34,796,363 — 2020 Notes 8,615,384 — — Employee Stock Purchase Plan 53,372 227,141 — Total potentially dilutive securities 24,050,691 56,910,149 12,829,617

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2020
Income Taxes
Schedule of components of Income tax expense	For the years ended December 31, 2020, 2019, and 2018 income tax expense consisted of the following (in thousands): Year ended December 31, 2020 2019 2018 Current tax expense: Federal $ — $ — $ — State 194 — — Current income tax expense 194 — — Deferred Federal — — — State — — — Deferred income tax expense — — — Total income tax expense $ 194 $ — $ —
Schedule of reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations	A reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations follows: December 31, 2020 2019 Income tax benefit using U.S. federal statutory rate 21.00 % 21.00 % State tax benefit, net of federal benefit (8.55) % 4.26 % Research and development tax credits 2.84 % 1.67 % Cancellation of debt — % (4.76) % Permanent items (0.60) % (1.41) % Change in the valuation allowance 35.09 % (20.33) % NOL and tax credit expiration under Section 382 (52.67) % — % Other 2.60 % (0.43) % (0.29) % — %
Schedule of principal components of deferred tax assets and liabilities	The principal components of the Company’s deferred tax assets and liabilities are as follows (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 86,665 $ 101,039 Capitalized research and development 1,565 2,230 Research and development credits 2,043 22,944 Stock-based compensation 4,041 4,445 Installment sale 9,981 — Other 888 1,451 Total deferred tax assets 105,183 132,109 Deferred tax liabilities: Debt discount (2,245) (3,702) Total deferred tax liabilities (2,245) (3,702) Net deferred tax asset prior to valuation allowance 102,938 128,407 Valuation allowance (102,938) (128,407) Net deferred tax asset $ — $ —

Restructurings (Tables)

Restructurings (Tables)	12 Months Ended
Restructurings (Tables)	Dec. 31, 2020
Restructurings
Schedule of accrued restructuring liabilities	The following table summarizes the accrued liabilities activity recorded in connection with the restructurings for the year ended December 31, 2020 (in thousands): Employee severance, benefits and related costs Amounts Charges Amount Adjustments Amounts October 2019 Restructuring 631 — (626) (5) — February 2020 Restructuring — 1,788 (1,812) 24 — August 2020 Restructuring — 2,993 (1,797) (169) 1,027 Total $ 631 $ 4,781 $ (4,235) $ (150) $ 1,027

Quarterly financial informati_2

Quarterly financial information (unaudited, in thousands, except per share data) (Tables)	12 Months Ended
	Dec. 31, 2020
Quarterly financial information (unaudited, in thousands, except per share data)
Schedule of Quarterly Financial Information	First Quarter Second Quarter Third Quarter Fourth Quarter Ended Ended Ended Ended March 31, June 30, September 30, December 31, 2020 2020 2020 2020 Revenue: Product revenue, net $ 5,034 $ 4,235 $ 5,829 $ 134 License and collaboration revenue 22 72 2,818 — Sale of COPIKTRA license and related assets — — 70,000 — Transition services revenue — — — 372 Total revenue 5,056 4,307 78,647 506 Operating expenses: Cost of sales - product $ 495 $ 392 $ 866 $ 12 Cost of sales - intangible amortization 392 393 8 — Cost of sales - sale of COPIKTRA license and related assets — — 31,187 — Research and development 10,924 9,344 10,955 10,153 Selling, general and administrative 19,604 15,442 20,614 7,095 Total operating expenses 31,415 25,571 63,630 17,260 (Loss) income from operations (26,359) (21,264) 15,017 (16,754) Other income/(expense) (1,313) — — — Interest income 356 122 19 18 Interest expense (10,674) (1,868) (1,898) (1,354) Loss on debt extinguishment — — — (1,580) Net (loss) income before income taxes (37,990) (23,010) 13,138 (19,670) Income tax expense — — — (194) Net (loss) income $ (37,990) $ (23,010) $ 13,138 $ (19,864) Net (loss) income per share —basic $ (0.35) $ (0.14) $ 0.08 $ (0.12) Net (loss) income per share —diluted $ (0.35) $ (0.14) $ 0.08 $ (0.12) Weighted-average number of common shares used in net loss per share —basic and diluted Net (loss) income per share —basic 108,153 165,395 169,510 169,902 Net (loss) income per share —diluted 108,153 165,395 169,760 169,902 First Quarter Second Quarter Third Quarter Fourth Quarter Ended Ended Ended Ended March 31, June 30, September 30, December 31, 2019 2019 2019 2019 Revenue: Product revenue, net $ 1,671 $ 3,019 $ 4,032 $ 3,617 License and collaboration revenue — 117 5,000 — Total revenue 1,671 3,136 9,032 3,617 Operating expenses: Cost of sales - product $ 158 $ 377 $ 371 $ 332 Cost of sales - intangible amortization 392 392 392 393 Research and development 9,758 11,346 12,219 12,455 Selling, general and administrative 26,033 29,298 22,153 23,728 Total operating expenses 36,341 41,413 35,135 36,908 Loss from operations (34,670) (38,277) (26,103) (33,291) Other income — — — (641) Interest income 1,497 1,268 1,005 611 Interest expense (4,929) (5,185) (5,041) (5,453) Net loss $ (38,102) $ (42,194) $ (30,139) $ (38,774) Net loss per share —basic $ (0.52) $ (0.57) $ (0.41) $ (0.51) Net loss per share —diluted $ (0.52) $ (0.57) $ (0.41) $ (0.51) Weighted-average number of common shares used in net loss per share —basic and diluted Net loss per share —basic 73,854 73,877 74,228 76,331 Net loss per share —diluted 73,854 73,877 74,228 76,331

Nature of business (Details)

Nature of business (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Nature of business
Cash, cash equivalents, restricted cash and investments	$ 147,500
Accumulated deficit	$ (592,511)	$ (524,785)

Significant accounting polici_4

Significant accounting policies - Segment and geographic information (Details)	12 Months Ended
	Dec. 31, 2020item
Segment and geographic information
Number of operating segments	1

Significant accounting polici_5

Significant accounting policies - Cash, cash equivalents and restricted cash (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Significant accounting policies
Cash and cash equivalents	$ 67,782	$ 43,514
Restricted cash	241	35,748
Total cash, cash equivalents and restricted cash	$ 68,023	$ 79,262	$ 130,608	$ 82,338

Significant accounting polici_6

Significant accounting policies - Cash, cash equivalents and restricted cash - Security deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted Cash and Cash Equivalents, Noncurrent	$ 241	$ 35,241
Restricted cash	241	35,748
Research and development agreement with the Leukemia and Lymphoma Society \| Prepaid Expenses and Other Current Assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash		500
Letter of credit \| Office and Laboratory Space in Needham, Massachusetts
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 200	200
Amended Term Loan Agreement
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash		$ 35,000

Significant accounting polici_7

Significant accounting policies - Fair Value Financial Instruments, Measured at Fair Value (Details) - Recurring basis - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial assets
Cash equivalents	$ 65,610	$ 77,176
Short-term investments	73,444	31,992
Long-term investments	5,995
Total financial assets	145,049	109,168
Derivative liability		450
Level 1
Financial assets
Cash equivalents	60,611	75,678
Total financial assets	60,611	75,678
Level 2
Financial assets
Cash equivalents	4,999	1,498
Short-term investments	73,444	31,992
Long-term investments	5,995
Total financial assets	$ 84,438	33,490
Level 3
Financial assets
Derivative liability		$ 450

Significant accounting polici_8

Significant accounting policies - Fair Value Financial Instruments, Derivative Liability (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Nov. 14, 2019	Oct. 17, 2018
Reconciliation of derivative liability
Derivative liability at	$ 450	$ 0
Fair value recognized upon issuance of Convertible Senior Notes		247
Fair value adjustment	1,313	641
Derivative liability extinguished upon conversion	(1,763)	(438)
Derivative liability at	$ 0	$ 450
5.00% Convertible Senior Notes due 2048
Derivative liability
Interest rate (as a percent)		5.00%		5.00%
5.00% Convertible Senior Notes due 2048 \| Risk-adjusted discount rate
Derivative liability
Debt Instrument, Measurement Input		13.08	12.06
5.00% Convertible Senior Notes due 2048 \| Cost Of Equity
Derivative liability
Debt Instrument, Measurement Input		16.54	17.05

Significant accounting polici_9

Significant accounting policies - Fair Value Financial Instruments, Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Financial liabilities
Debt, carrying value	$ 0	$ 35.1
Level 3
Financial liabilities
Debt, fair value	0	37
Level 3 \| 5.00% Convertible Senior Notes due 2048
Financial liabilities
Debt, carrying value	19.1	68.6
Debt, fair value	0.3	12.5
Level 3 \| 5.00% Convertible Senior Second Lien Notes due 2048
Financial liabilities
Debt, fair value		$ 50.5
Level 3 \| 5.00% Convertible Senior Third Lien Notes due 2048
Financial liabilities
Debt, fair value	$ 30

Significant accounting polic_10

Significant accounting policies - Investments (Details)	12 Months Ended
Significant accounting policies - Investments (Details)	Dec. 31, 2020USD ($)item	Dec. 31, 2019USD ($)item	Dec. 31, 2018USD ($)
Investments
Cash, cash equivalents & restricted cash	$ 67,782,000	$ 43,514,000
Gross unrealized gains	1,000
Total cash, cash equivalents, restricted cash, gross unrealized gains	56,000	14,000
Total cash, cash equivalents, restricted cash, gross unrealized losses	(3,000)
Total cash, cash equivalents, restricted cash and investments, Fair Value	147,500,000
Realized gains or losses on investments	$ 0	$ 0	$ 0
Number of investments in unrealized loss position \| item	1	2
Number of investments in unrealized loss position for more than 12 months	0	0
Unrealized loss on fair value	$ 6,000,000	$ 5,800,000
Amortized Cost
Investments
Total cash, cash equivalents, restricted cash and investments	147,409,000	111,241,000
Fair Value
Investments
Total cash, cash equivalents, restricted cash and investments, Fair Value	147,462,000	111,255,000
Cash and cash equivalents \| Amortized Cost
Investments
Cash, cash equivalents & restricted cash	68,022,000	79,262,000
Cash and cash equivalents \| Fair Value
Investments
Cash and cash equivalents, Fair value	68,023,000	79,262,000
Cash and money market accounts \| Amortized Cost
Investments
Cash, cash equivalents & restricted cash	63,024,000	77,764,000
Cash and money market accounts \| Fair Value
Investments
Cash and cash equivalents, Fair value	$ 63,024,000	$ 77,764,000
Corporate bonds, agency bonds and commercial paper
Investments
Original maturity period, cash and cash equivalents	90 days	90 days
Gross unrealized gains	$ 1,000
Corporate bonds, agency bonds and commercial paper \| Amortized Cost
Investments
Cash, cash equivalents & restricted cash	4,998,000	$ 1,498,000
Corporate bonds, agency bonds and commercial paper \| Fair Value
Investments
Cash and cash equivalents, Fair value	$ 4,999,000	1,498,000
Minimum \| Corporate bonds, agency bonds and commercial paper
Investments
Maturity period, investments	1 year
Maximum \| Corporate bonds, agency bonds and commercial paper
Investments
Maturity period, investments	5 years
Investments
Investments
Gross unrealized gains	$ 55,000	14,000
Gross unrealized losses	(3,000)
Investments \| Amortized Cost
Investments
Investments	79,387,000	31,979,000
Investments \| Fair Value
Investments
Investments	$ 79,439,000	$ 31,993,000
Corporate bonds and commercial paper
Investments
Maturity period, investments		1 year
Gross unrealized gains		$ 14,000
Corporate bonds and commercial paper \| Amortized Cost
Investments
Due within 1 year		31,979,000
Corporate bonds and commercial paper \| Fair Value
Investments
Due within 1 year		$ 31,993,000
Corporate bonds, agency bonds and commercial paper
Investments
Maturity period, investments	1 year
Gross unrealized gains	$ 55,000
Gross unrealized losses	(3,000)
Corporate bonds, agency bonds and commercial paper \| Amortized Cost
Investments
Due within 1 year	73,389,000
Due between 1 and 5 years	5,998,000
Corporate bonds, agency bonds and commercial paper \| Fair Value
Investments
Due within 1 year	73,444,000
Due between 1 and 5 years	$ 5,995,000

Significant accounting polic_11

Significant accounting policies - Concentration of Credit Risk (Details)	12 Months Ended		24 Months Ended
	Dec. 31, 2020Institutioncustomer	Dec. 31, 2019customer	Dec. 31, 2020customer
Concentrations of credit risk and off-balance sheet risk
Off-balance sheet concentrations of credit risk description	As of December 31, 2020, the Company’s cash, cash equivalents and investments were deposited at three financial institutions and it has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements.
Number of financial institutions in which cash, cash equivalents and investments were deposited \| Institution	3
Trade accounts receivable \| Credit Concentration Risk
Concentrations of credit risk and off-balance sheet risk
Number of customer			2
Trade accounts receivable \| Credit Concentration Risk \| Minimum
Concentrations of credit risk and off-balance sheet risk
Percentage	50.00%	50.00%
Revenue \| Customer Concentration Risk
Concentrations of credit risk and off-balance sheet risk
Number of customer	4	4
Revenue \| Customer Concentration Risk \| Minimum
Concentrations of credit risk and off-balance sheet risk
Percentage	10.00%	10.00%

Significant accounting polic_12

Significant accounting policies - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property and equipment, net
Impairment losses on long-lived assets	$ 0
Laboratory equipment
Property and equipment, net
Estimated useful lives	5 years
Furniture and fixtures
Property and equipment, net
Estimated useful lives	5 years
Computer equipment
Property and equipment, net
Estimated useful lives	3 years
Exclusive license agreement \| Infinity
Other assets
Prepaid CRO Expenses	$ 0	$ 800

Significant accounting polic_13

Significant accounting policies - Revenue Recognition and Accounts Receivable, Net (Details)	12 Months Ended
	Dec. 31, 2020
Minimum
Accounts Receivable
Threshold accounts receivable typically due	30 days
Maximum
Accounts Receivable
Threshold accounts receivable typically due	90 days
Prior to product's expiration
Revenue recognition
Period for eligible returns of expired product	3 months
After product's expiration date
Revenue recognition
Period for eligible returns of expired product	6 months

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Inventory
Raw materials			$ 955
Work in process			2,040
Finished goods			101
Total inventories			$ 3,096
Cost Of Sale, License And Related Assets		$ 31,187
Copiktra license and related assets
Inventory
Cost Of Sale, License And Related Assets	$ 31,187
Copiktra license and related assets \| Duvelisib inventory \| Secura
Inventory
Cost Of Sale, License And Related Assets		$ 6,000

Property and equipment, net (De

Property and equipment, net (Details) $ in Thousands	12 Months Ended
Property and equipment, net (Details) $ in Thousands	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Feb. 15, 2018ft²	Apr. 15, 2014ft²
Property and equipment
Property and equipment, gross	$ 1,885	$ 1,885
Less: accumulated depreciation	(1,469)	(938)
Property and equipment, net	416	947
Depreciation expenses	531	429	$ 996
Office and Laboratory Space in Needham, Massachusetts
Property and equipment
Area of space \| ft²				27,810	15,197
Area of office space vacated \| ft²				15,197
Leasehold improvements
Property and equipment
Property and equipment, gross	146	146
Gain or loss from disposal of leasehold improvements			$ 0
Furniture and fixtures
Property and equipment
Property and equipment, gross	1,074	1,074
Computer equipment
Property and equipment
Property and equipment, gross	$ 665	$ 665

Intangible assets (Details)

Intangible assets (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
Intangible assets (Details) - USD ($) $ in Thousands	Nov. 30, 2018	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 24, 2018
Intangible assets
Payments for milestone payment					$ 22,000
Amortization of acquired intangible asset			$ 793	$ 1,569	$ 423
Cost Of Sale, License And Related Assets			31,187
Copiktra license and related assets
Intangible assets
Cost Of Sale, License And Related Assets		$ 31,187
Acquired and in-license rights
Intangible assets
Intangible assets, gross						$ 22,000
Payments for milestone payment	$ 22,000
Secura \| Acquired and in-license rights \| Copiktra license and related assets
Intangible assets
Cost Of Sale, License And Related Assets			$ 19,200

Accrued expenses (Details)

Accrued expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued expenses
Compensation and related benefits	$ 5,930	$ 7,399
Research and development expenses	5,176	5,467
Commercialization costs	330	3,028
Interest	236	897
Consulting fees	1,091	1,610
Professional fees	615	573
Other	1,282	391
Total accrued expenses	$ 14,660	$ 19,365

Long-term debt - Hercules term

Long-term debt - Hercules term loan facility (Details) - USD ($) $ in Thousands	Nov. 09, 2020	Nov. 14, 2019	Apr. 23, 2019	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Apr. 22, 2019	Mar. 21, 2017
Long-term debt
Amount drawn						$ 9,670	$ 9,900
Restricted cash				$ 241	$ 241	35,748
Loss on debt extinguishment				$ (1,580)	(1,580)
Amended Term Loan Agreement
Long-term debt
Restricted cash						35,000
Repayment of term loan	$ 37,400
Repayment of principal	35,000
Repayment of final payment	1,800
Prepayment penalty fee	500
Accrued and unpaid interest	100
Loss on debt extinguishment					$ 1,600
Carrying amount of the debt excluding accrued interest	$ 1,600
Medium-term Notes [Member] \| Original Loan Agreement
Long-term debt
Maximum borrowing capacity									$ 25,000
Medium-term Notes [Member] \| Amended Term Loan Agreement
Long-term debt
Maximum borrowing capacity		$ 75,000	$ 75,000
Outstanding amount			35,000					$ 25,000
Amount drawn			10,000
Remaining borrowing capacity			$ 40,000
Restricted cash						$ 35,000
Medium-term Notes [Member] \| Amended Term Loan Agreement \| Prime rate
Long-term debt
Basis spread			5.50%
Medium-term Notes [Member] \| Amended Term Loan Agreement \| Minimum
Long-term debt
Interest rate			9.75%
Basis spread			9.75%
Medium-term Notes [Member] \| Amended Term Loan Agreement \| Maximum
Long-term debt
Interest rate			12.00%
Medium-term Notes [Member] \| Amended Term Loan Agreement \| On or before April 30, 2020
Long-term debt
Net product revenue			$ 37,500
Medium-term Notes [Member] \| Amended Term Loan Agreement \| On or before June 30, 2020
Long-term debt
Net product revenue			50,000
Medium-term Notes [Member] \| Amended Term Loan Agreement \| Trailing six months prior to December 31, 2020
Long-term debt
Net product revenue		$ 20,000	40,000
Debt Covenant, Initial Net Product Revenue Threshold, Measurement Period					6 months
Percentage of restricted cash, collateral		100.00%
Medium-term Notes [Member] \| Amended Term Loan Agreement \| Company's option through December 31, 2021
Long-term debt
Amount drawn			25,000
Debt Covenant, Initial Net Product Revenue Threshold, Measurement Period					6 months
Medium-term Notes [Member] \| Amended Term Loan Agreement \| Plan \| Maximum
Long-term debt
Amount drawn			$ 15,000

Product revenue reserves and _3

Product revenue reserves and allowances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	$ 814	$ 276
Provision related to sales in the current year	3,376	2,500
Adjustments related to prior period sales		(76)
Credits and payments made	(4,069)	(1,886)
Product revenue reserves and allowances at ending	121	814
Trade discounts and allowances
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	111	29
Provision related to sales in the current year	640	512
Credits and payments made	(728)	(430)
Product revenue reserves and allowances at ending	23	111
Third-Party Payer chargebacks, discounts and fees
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	255	88
Provision related to sales in the current year	1,820	1,306
Credits and payments made	(2,075)	(1,139)
Product revenue reserves and allowances at ending		255
Government rebates and other incentives
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	372	157
Provision related to sales in the current year	609	608
Adjustments related to prior period sales		(76)
Credits and payments made	(914)	(317)
Product revenue reserves and allowances at ending	67	372
Returns
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	76	2
Provision related to sales in the current year	307	74
Credits and payments made	(352)
Product revenue reserves and allowances at ending	$ 31	$ 76

Leases - Leases (Details)

Leases - Leases (Details) - Office and Laboratory Space in Needham, Massachusetts	Feb. 15, 2018USD ($)ft²	Apr. 15, 2014ft²
Leases
Area of space \| ft²	27,810	15,197
Minimum
Leases
Operating lease expense	$ 660,000
Maximum
Leases
Operating lease expense	$ 1,100,000

Leases - Balance sheet and othe

Leases - Balance sheet and other information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases
Right-of use asset	$ 2,726	$ 3,077
Lease liability	3,489
Lease Expense
Operating lease expense	885	885
Total Lease Expense	885	885
Other Information - Operating Leases
Operating cash flows paid for amounts included in measurement of lease liabilities	$ 955	$ 703
Weighted average remaining lease term (in years)	4 years 6 months
Weighted average discount rate	14.60%
Maturity Analysis
2021	$ 1,019
2022	1,039
2023	1,060
2024	1,081
2025	546
Total	4,745
Less: Present value discount	(1,256)
Lease Liability	$ 3,489

Common stock (Details)

Common stock (Details) $ / shares in Units, $ in Thousands	Mar. 03, 2020USD ($)	Feb. 27, 2020$ / sharesshares	Aug. 28, 2017USD ($)	Mar. 30, 2017USD ($)	Dec. 31, 2020USD ($)Voteshares	Dec. 31, 2018USD ($)	Dec. 31, 2019shares	Dec. 18, 2018shares
Common stock
Shares reserved for issuance					39,129,000		62,124,000
Number of votes entitled for each share of common stock \| Vote					1
Common stock
Proceeds from Issuance of Common Stock \| $					$ 106,059	$ 105,156
Private Investment in Public Equity (PIPE)
Common stock
Shares issued (in shares)		46,511,628
Proceeds from Issuance of Common Stock \| $	$ 93,800
Share price (in dollars per share) \| $ / shares		$ 2.15
Share price premium (as percentage)		12.60%
Share price, prior to premium price (in dollars per share) \| $ / shares		$ 1.91
Common stock
Common stock
Shares issued (in shares)					46,511,628
Common stock \| At-the-market equity offering program
Common stock
Shares issued (in shares)					6,769,559
Proceeds from Issuance of Common Stock \| $					$ 12,200
Shares, Outstanding					18,287,913
Net proceeds from issuance of stock \| $					$ 59,600
2017 ATM Program \| Common stock \| At-the-market equity offering program
Common stock
Maximum value of common stock allowed to be sold \| $			$ 75,000	$ 35,000
Inducement Award Program
Common stock
Shares reserved for issuance					4,058,000		6,331,000
Convertible Common Stock [Member] \| 5.00% Convertible Senior Notes due 2048
Common stock
Shares reserved for issuance					42,000		3,950,000
Convertible Common Stock [Member] \| 5.00% Convertible Senior Second Lien Notes due 2048
Common stock
Shares reserved for issuance							34,796,000
Convertible Common Stock [Member] \| 5.00% Convertible Senior Third Lien Notes due 2048
Common stock
Shares reserved for issuance					8,615,000
Equity compensation plans
Common stock
Shares reserved for issuance					25,114,000		15,389,000
Employee Stock purchase plan
Common stock
Shares reserved for issuance					1,300,000		1,658,000	2,000,000
Common stock
Proceeds from Issuance of Common Stock \| $					$ 400

Common stock - Equity offerings

Common stock - Equity offerings (Details) - Common stock - USD ($) $ / shares in Units, $ in Millions	Jun. 14, 2018	May 23, 2018	May 16, 2018	Dec. 31, 2020
Common stock
Issuance of common stock resulting from private investment in public equity offering, net of issuance costs (in shares)				46,511,628
Cantor \| Follow-on offerings \| Underwriting Agreement
Common stock
Issuance of common stock resulting from private investment in public equity offering, net of issuance costs (in shares)		1,166,666
Net proceeds from issuance of stock		$ 38.3
Options are exercisable from date of prospectus supplement			30 days
Cantor \| Follow-on offerings \| Underwriting Agreement \| Plan
Common stock
Issuance of common stock resulting from private investment in public equity offering, net of issuance costs (in shares)			7,777,778
Share price (in dollars per share)			$ 4.31
Consonance \| Follow-on offerings \| Purchase Agreement
Common stock
Issuance of common stock resulting from private investment in public equity offering, net of issuance costs (in shares)	7,166,666
Share price (in dollars per share)	$ 6
Net proceeds from issuance of stock	$ 42.9

Stock-based compensation - Stoc

Stock-based compensation - Stock-Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock-based compensation
Total stock-based compensation expense	$ 8,118	$ 8,539	$ 6,671
Research and development expense.
Stock-based compensation
Total stock-based compensation expense	1,935	1,501	2,043
Selling, General And Administrative Expense [Member]
Stock-based compensation
Total stock-based compensation expense	$ 6,183	$ 7,038	$ 4,628

Stock-based compensation - Equi

Stock-based compensation - Equity Plans (Details)	12 Months Ended
Stock-based compensation - Equity Plans (Details)	Dec. 31, 2020item
Stock-based compensation
Number of equity compensation plans	2
Stock options
Stock-based compensation
Expiration term	10 years
Stock options \| Four Annual Payments
Stock-based compensation
Vesting percentage	25.00%
Vesting period	1 year
Stock options \| First Anniversary Payment
Stock-based compensation
Vesting percentage	6.25%
Vesting period	3 months

Stock-based compensation - St_2

Stock-based compensation - Stock Plans and Activity (Details) - shares

Jan. 01, 2018

Jan. 01, 2017

Jan. 01, 2016

Feb. 29, 2020

Dec. 31, 2018

Jun. 30, 2018

Dec. 31, 2017

Dec. 31, 2016

Feb. 29, 2012

Dec. 31, 2020

May 19, 2020

Dec. 18, 2018

Dec. 31, 2014

Stock options

Stock-based compensation

Granted (in shares)

2,291,815

Exercised (in shares)

1,498,355

Restricted stock units

Stock-based compensation

Granted (in shares)

4,471,534

Forfeited (in shares)

479,524

Vested (in shares)

2,020,782

2012 Incentive Plan

Stock-based compensation

Number of shares reserved

3,428,571

13,000,000

16,628,425

Additional number of shares authorized for issuance

1,285,714

30,101

Percentage of outstanding shares of common stock used to compute annual increase in number of shares reserved

4.00%

Shares available for future grants

10,947,871

2012 Incentive Plan | Maximum

Stock-based compensation

Annual increase in number of shares reserved

1,285,714

2012 Incentive Plan | Stock options

Stock-based compensation

Granted (in shares)

21,727,798

Forfeited (in shares)

8,496,099

Exercised (in shares)

1,735,524

2012 Incentive Plan | Restricted stock units

Stock-based compensation

Granted (in shares)

6,371,656

Forfeited (in shares)

922,801

Vested (in shares)

2,847,038

Inducement Award Program

Stock-based compensation

Number of shares reserved

750,000

Additional number of shares authorized for issuance

1,250,000

1,700,000

2,500,000

580,000

Shares available for future grants

2,879,688

Inducement Award Program | Stock options

Stock-based compensation

Granted (in shares)

6,392,134

Forfeited (in shares)

4,722,689

Exercised (in shares)

543,446

Inducement Award Program | Restricted stock units

Stock-based compensation

Granted (in shares)

184,700

Forfeited (in shares)

62,200

Vested (in shares)

70,000

Reduction of shares available for issuance

2,033,367

Stock-based compensation - St_3

Stock-based compensation - Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Additional disclosures
Stock-based compensation expense	$ 8,118	$ 8,539	$ 6,671
Stock options
Shares
Outstanding at the beginning of the period (in shares)	17,258,524
Granted (in shares)	2,291,815
Exercised (in shares)	(1,498,355)
Forfeited/cancelled (in shares)	(5,361,239)
Outstanding at the end of the period (in shares)	12,690,745	17,258,524
Vested at the end of the period (in shares)	8,053,260
Weighted-average exercise price per share
Outstanding at the beginning of the period (in dollars per share)	$ 4
Granted (in dollars per share)	2.11
Exercised (in dollars per share)	1.72
Forfeited/cancelled (in dollars per share)	4.05
Outstanding at the end of the period (in dollars per share)	3.90	$ 4
Vested at the end of the period (in dollars per share)	$ 4.70
Weighted-average remaining contractual term
Outstanding at the end of the period	6 years 6 months	7 years 3 months 18 days
Vested at the end of the period	5 years 2 months 12 days
Aggregate intrinsic value
Outstanding at the beginning of the period (in dollars)	$ 185
Outstanding at the end of the period (in dollars)	3,390	$ 185
Vested at the end of the period (in dollars)	2,150
Aggregate intrinsic value of options exercised (in dollars)	$ 1,000	$ 100
Assumptions used to estimate fair value of each stock-based award on the grant date
Risk-free interest rate (as a percent)	0.60%	1.98%	2.65%
Volatility (as a percent)	96.00%	87.00%	81.00%
Dividend yield (as a percent)	0.00%	0.00%	0.00%
Expected term	6 years	5 years 10 months 24 days	5 years 9 months 18 days
Additional disclosures
Stock-based compensation expense	$ 4,300	$ 7,100	$ 5,600
Weighted-average grant date fair value (in dollars per share)	$ 1.62	$ 1.44	$ 3.72
Fair value of vested stock options	$ 7,400	$ 7,300	$ 4,700
Total unrecognized stock-based compensation expense (in dollars)	$ 7,100
Weighted-average recognition period	2 years 7 months 6 days

Stock-based compensation - Rest

Stock-based compensation - Restricted Stock (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)itememployee$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares	Dec. 31, 2018USD ($)
Additional disclosures
Stock-based compensation expense	$ 8,118	$ 8,539	$ 6,671
Restricted stock units
Stock-based compensation
Number of shares holder to receive when RSU vests \| shares	1
Shares
Unvested at the beginning of the period (in shares) \| shares	678,089
Granted (in shares) \| shares	4,471,534
Vested (in shares) \| shares	(2,020,782)
Forfeited (in shares) \| shares	(479,524)
Unvested at the end of the period (in shares) \| shares	2,649,317	678,089
Weighted-average grant date fair value
Unvested at the beginning of the period (in dollars per share) \| $ / shares	$ 2.36
Granted (in dollars per share) \| $ / shares	1.64
Vested (in dollars per share) \| $ / shares	1.60
Forfeited/cancelled (in dollars per share) \| $ / shares	2.27
Unvested at the end of the period (in dollars per share) \| $ / shares	$ 1.73	$ 2.36
Additional disclosures
Stock-based compensation expense	$ 3,700	$ 1,000	400
Fair value of shares vested	3,800	$ 300	$ 0
Unrecognized stock-based compensation expense	$ 3,800
Weighted-average recognition period	1 year 6 months
Number of affected employees \| employee	93
Incremental stock compensation expense to be recognized over the remaining requisite service period	$ 200
Incremental stock compensation expense	100
Restricted stock units \| Selling, general and administrative expenses
Additional disclosures
Stock-based compensation expense	$ 500
Restricted stock units \| Four Annual Payments
Stock-based compensation
Number of installments \| item	4
Number of anniversaries \| item	4
Restricted stock units \| First Anniversary Payment
Stock-based compensation
Vesting percentage	100.00%

Stock-based compensation - Empl

Stock-based compensation - Employee Stock Purchase Plan (Details) $ in Thousands	Dec. 18, 2018itemshares	Dec. 31, 2020USD ($)shares	Dec. 31, 2019USD ($)shares	Dec. 31, 2018USD ($)
Stock-based compensation
Shares reserved for issuance \| shares		39,129,000	62,124,000
Assumptions used to estimate fair value of each stock-based award on the grant date
Stock-based compensation expense		$ 8,118	$ 8,539	$ 6,671
Proceeds from the issuance of common stock, net		$ 106,059		$ 105,156
Employee Stock purchase plan
Stock-based compensation
Percent of common stock at market price to be purchased	85.00%
Number of vesting periods \| item	2
Vesting period	6 months
Shares reserved for issuance \| shares	2,000,000	1,300,000	1,658,000
Assumptions used to estimate fair value of each stock-based award on the grant date
Risk-free interest rate (as a percent)		1.04%	2.26%
Volatility (as a percent)		109.00%	88.00%
Expected term		6 months	6 months
Stock-based compensation expense		$ 100	$ 400
Issuance of common stock under ESPP \| shares		358,193	341,701
Proceeds from the issuance of common stock, net		$ 400

Convertible Senior Notes (Detai

Convertible Senior Notes (Details) $ / shares in Units, $ in Thousands	Nov. 06, 2020USD ($)D$ / shares	Dec. 23, 2019USD ($)D$ / shares	Nov. 14, 2019USD ($)D$ / shares	Dec. 18, 2018USD ($)	Oct. 17, 2018USD ($)Ditem$ / shares	Dec. 31, 2019USD ($)$ / shares	Mar. 31, 2020USD ($)shares	Dec. 31, 2019USD ($)$ / shares	Dec. 31, 2020USD ($)$ / shares	Dec. 31, 2019USD ($)$ / sharesshares	Dec. 31, 2018USD ($)	Nov. 11, 2018$ / shares	Oct. 11, 2018$ / shares
Convertible Notes
Repayments of Convertible Debt										$ 12,174
Net proceeds											$ 145,297
Common stock, par value (in dollars per share) \| $ / shares						$ 0.0001		$ 0.0001	$ 0.0001	$ 0.0001
Change in fair value of conversion feature									$ (1,313)	$ (641)	25,556
Change in fair value of conversion option of Notes on exchange									2,331	13,640
Other Nonoperating Income (Expenses)							$ (1,313)	$ (641)	(1,313)	(641)	$ 25,556
Interest make-whole payments on the 2019 Notes									1,763	$ 438
5.00% Convertible Senior Notes due 2048
Convertible Notes
Aggregate principal amount	$ 28,000				$ 150,000
Debt Conversion, Original Debt, Amount		$ 7,400	$ 114,300
Repayments of Convertible Debt		700	11,400
Interest rate (as a percent)					5.00%	5.00%		5.00%		5.00%
Net proceeds					$ 145,300
Common stock, par value (in dollars per share) \| $ / shares					$ 0.0001
Initial conversion rate					139.5771
Initial conversion price of Common Stock \| $ / shares					$ 7.16
Conversion premium above the last reported sales price of the Common Stock (as a percent)					15.00%
Sale price of the Common Stock \| $ / shares													$ 6.23
Percentage of stock price trigger for conversion					130.00%
Trading days \| item					20
Consecutive trading days \| D					30
Percentage price of principal amount to be purchased plus accrued and unpaid interest					100.00%
Debt discount					$ 51,500
Derivative liability					$ 51,500
Fair value adjustment				$ 25,900
Change in fair value of conversion feature				$ 25,600
5.00% Convertible Senior Second Lien Notes due 2048
Convertible Notes
Debt Conversion, Original Debt, Amount										$ 9,500
Debt Conversion, Converted Instrument, Amount		$ 4,000	$ 62,900				57,400
Interest rate (as a percent)		5.00%	5.00%
Gains (Losses) on Restructuring of Debt									0
Common stock, par value (in dollars per share) \| $ / shares		$ 0.0001	$ 0.0001
Initial conversion rate		606.0606	606.0606
Initial conversion price of Common Stock \| $ / shares		$ 1.65	$ 1.65
Conversion premium above the last reported sales price of the Common Stock (as a percent)		52.80%	52.80%
Sale price of the Common Stock \| $ / shares		$ 1.08										$ 1.08
Percentage of stock price trigger for conversion		121.00%	121.00%
Trading days \| D		20	20
Consecutive trading days \| D		30	30
Debt discount		$ 200
Derivative liability		$ 200
Change in fair value of conversion option of Notes on exchange									13,600
Fair value of 2019 Interest Make-Whole Provision						$ 500		$ 500		$ 500
Other Nonoperating Income (Expenses)						$ 600			1,300
Interest expense									$ 12,100
Debt conversion, Converted Instrument, Cash							$ 1,800
Debt Conversion, Converted Instrument, Shares Issued \| shares							34,796,350			5,767,872
Interest make-whole payments on the 2019 Notes										$ 400
5.00% Convertible Senior Third Lien Notes due 2048
Convertible Notes
Aggregate principal amount	$ 28,000
Interest rate (as a percent)	5.00%
Initial conversion rate	307.6923
Initial conversion price of Common Stock \| $ / shares	$ 3.25
Conversion premium above the last reported sales price of the Common Stock (as a percent)	153.90%
Sale price of the Common Stock \| $ / shares	$ 1.28
Percentage of stock price trigger for conversion	123.08%
Trading days \| D	20
Consecutive trading days \| D	30
Percentage price of principal amount to be purchased plus accrued and unpaid interest	100.00%
Change in fair value of conversion option of Notes on exchange	$ 2,300

Net Loss per share - basic and

Net Loss per share - basic and diluted net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Computation of basic and diluted net income (loss) per share:
Net loss	$ (19,864)	$ 13,138	$ (23,010)	$ (37,990)	$ (38,774)	$ (30,139)	$ (42,194)	$ (38,102)	$ (67,726)	$ (149,209)	$ (72,434)
Less: Other income											(25,556)
Add: Interest expense											3,071
Adjusted diluted net loss									$ (67,726)	$ (149,209)	$ (94,919)
Weighted average shares outstanding - basic									153,330,000	74,578,000	64,962,000
Effect of dilutive securities: 2018 Notes											4,359,391
Weighted average shares outstanding - diluted	169,902,000	169,760,000	165,395,000	108,153,000	76,331,000	74,228,000	73,877,000	73,854,000	153,330,000	74,578,000	69,321,000
Net loss per share-basic	$ (0.12)	$ 0.08	$ (0.14)	$ (0.35)	$ (0.51)	$ (0.41)	$ (0.57)	$ (0.52)	$ (0.44)	$ (2)	$ (1.12)
Net loss per share-diluted	$ (0.12)	$ 0.08	$ (0.14)	$ (0.35)	$ (0.51)	$ (0.41)	$ (0.57)	$ (0.52)	$ (0.44)	$ (2)	$ (1.37)

Net Loss per share (Details)

Net Loss per share (Details) - USD ($) $ in Thousands	12 Months Ended
Net Loss per share (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net loss per share
Change in fair value of the bifurcated derivative			$ (25,556)
Interest expense			$ 3,071
Number of shares at issue			20,936,548
Number of shares at issuance			20,936,548
Number of days outstanding to calculate weighted average shares			76 days
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	24,050,691	56,910,149	12,829,617
Weighted-average number of shares of adjustments			4,359,391
Stock options
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	12,690,745	17,258,524	12,522,867
Restricted stock units
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	2,649,317	678,089	306,750
Employee Stock purchase plan
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	53,372	227,141
5.00% Convertible Senior Notes due 2048 \| Convertible Common Stock [Member]
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	41,873	3,950,032
5.00% Convertible Senior Second Lien Notes due 2048 \| Convertible Common Stock [Member]
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)		34,796,363
5.00% Convertible Senior Third Lien Notes due 2048 \| Convertible Common Stock [Member]
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	8,615,384

Income Taxes - Operating Loss C

Income Taxes - Operating Loss Carryforwards (Details) $ in Millions	Dec. 31, 2020USD ($)
Federal
Operating loss carryforwards
NOL carryforwards	$ 348.5
Operating loss carryforwards, indefinite period	154.5
NOL carryforwards subject to limitation	41.4
State
Operating loss carryforwards
NOL carryforwards	231.9
NOL carryforwards subject to limitation	$ 168

Income Taxes - Tax Credits (Det

Income Taxes - Tax Credits (Details) $ in Millions	Dec. 31, 2020USD ($)
Federal
Tax credit carryforwards
Tax credits	$ 1.6
State
Tax credit carryforwards
Tax credits	$ 0.6

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current tax expense:
Federal		$ 0	$ 0	$ 0
State		194	0	0
Current income tax expense		194	0	0
Deferred
Federal		0	0	0
State		0	0	0
Deferred income tax expense		0	0	0
Total income tax expense	$ 194	$ 194	$ 0	$ 0

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Taxes and Deferred Tax Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of income taxes computed using the U.S. federal statutory rate
Income tax benefit using U.S. federal statutory rate (as a percent)	21.00%	21.00%
State tax benefit, net of federal benefit (as a percent)	(8.55%)	4.26%
Research and development tax credits (as a percent)	2.84%	1.67%
Cancellation of debt		(4.76%)
Permanent items (as a percent)	(0.60%)	(1.41%)
Change in the valuation allowance (as a percent)	35.09%	(20.33%)
NOL and tax credit expiration under Section 382 (as a percent)	(52.67%)
Other (as a percent)	2.60%	(0.43%)
Effective income tax rate (as a percent)	(0.29%)
Deferred tax assets:
Net operating loss carryforwards	$ 86,665	$ 101,039
Capitalized research and development	1,565	2,230
Research and development credits	2,043	22,944
Stock-based compensation	4,041	4,445
Installment sale	9,981
Other	888	1,451
Total deferred tax assets	105,183	132,109
Deferred tax liabilities:
Debt Discount	(2,245)	(3,702)
Total deferred tax liabilities	(2,245)	(3,702)
Net deferred tax asset prior to valuation allowance	102,938	128,407
Valuation allowance	(102,938)	$ (128,407)
Additional disclosures
Increase (decrease) in valuation allowance	(25,500)
Unrecognized tax benefits	0
Interest and penalties accrued related to unrecognized tax benefits	0
Liability for uncertain tax positions	$ 0

Commitments and contingencies (

Commitments and contingencies (Details) - Office and Laboratory Space in Needham, Massachusetts $ in Millions	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Feb. 15, 2018ft²	Apr. 15, 2014ft²
Property, Plant and Equipment [Line Items]
Area of space \| ft²			27,810	15,197
Letter of credit \| Restricted Cash and Cash Equivalents, Noncurrent [Member]
Property, Plant and Equipment [Line Items]
Security deposit \| $	$ 0.2	$ 0.2

License, collaboration and co_2

License, collaboration and commercial agreements - Secura Bio Inc (Details) - USD ($) $ in Thousands	Jul. 25, 2019	Sep. 30, 2020	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Term of agreement		1 year
Number of days written prior notice required for other party to terminate agreement		5 days
Revenue recognized			$ 506	$ 78,647	$ 4,307	$ 5,056	$ 3,617	$ 9,032	$ 3,136	$ 1,671	$ 88,516	$ 17,456	$ 26,718
Cost of sales - sale of COPIKTRA license and related assets											31,187
Earnings Per Share, Pro Forma [Abstract]
Net loss			(19,864)	13,138	$ (23,010)	$ (37,990)	$ (38,774)	$ (30,139)	$ (42,194)	$ (38,102)	(67,726)	$ (149,209)	$ (72,434)
Copiktra license and related assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized				70,000							70,000
Cost of sales - sale of COPIKTRA license and related assets				31,187
Transition Services Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized			$ 372								372
Secura \| Duvelisib inventory \| Copiktra license and related assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cost of sales - sale of COPIKTRA license and related assets											6,000
License and Collaboration Agreement \| Secura
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment		$ 70,000
Milestone payments receivable upon approval of COPIKTRA		35,000		35,000
Milestone payments receivable upon approval for commercial sale		10,000		10,000
Threshold sales to trigger royalty payments		$ 100,000
Percentage of all royalty, milestone and sublicense revenue payments payable		50.00%
Percentage of all royalty and milestone payments payable under certain jurisdictions		50.00%
Cost of sales - sale of COPIKTRA license and related assets											31,200
License and Collaboration Agreement \| Secura \| Copiktra license and related assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized											70,000
License and Collaboration Agreement \| Secura \| Transition Services Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized											400
License and Collaboration Agreement \| Secura \| Sales Exceeds $100 Million
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sales milestone receivable		$ 10,000		10,000
Threshold sales to trigger milestone payments		100,000
License and Collaboration Agreement \| Secura \| Sales Exceeds $200 Million
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sales milestone receivable		15,000		15,000
Threshold sales to trigger milestone payments		200,000
License and Collaboration Agreement \| Secura \| Sales Exceeds $300 Million
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sales milestone receivable		25,000		25,000
Threshold sales to trigger milestone payments		300,000
License and Collaboration Agreement \| Secura \| Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Regulatory milestone payments		45,000		45,000
Sales milestone receivable		$ 50,000		$ 50,000
License and Collaboration Agreement \| Secura \| Intangible asset
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cost of sales - sale of COPIKTRA license and related assets											19,200
License and Collaboration Agreement \| Secura \| Duvelisib inventory
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cost of sales - sale of COPIKTRA license and related assets											6,000
License and Collaboration Agreement \| Secura \| Manufacturing equipment
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cost of sales - sale of COPIKTRA license and related assets											200
License and Collaboration Agreement \| Secura \| Duvelisib contract prepaid balances
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cost of sales - sale of COPIKTRA license and related assets											$ 5,800
License and Collaboration Agreement \| Sanofi
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Agreement obligations expire from first commercial sale of product (in years)	10 years
Maximum aggregate payments entitled to receive if all milestones successfully achieved	$ 42,000
Number of days written prior notice required for other party to terminate agreement	180 days

License, collaboration and co_3

License, collaboration and commercial agreements - Chugai Pharmaceutical Co., Ltd (Chugai) (Details) - USD ($) $ in Millions	Jan. 07, 2020	Sep. 30, 2020	Dec. 31, 2020
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of days written prior notice required for other party to terminate agreement		5 days
Chugai Pharmaceutical Co., Ltd. \| License and Collaboration Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
One-time cash payment	$ 3
Agreement obligations expire from first commercial sale of product (in years)	12 years
Number of days written prior notice required for other party to terminate agreement	180 days
Number of days written notice required to terminate agreement if fails to cure breach	120 days
Chugai Pharmaceutical Co., Ltd. \| License and Collaboration Agreement \| Research and development expense.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
One-time cash payment			$ 3

License, collaboration and co_4

License, collaboration and commercial agreements - Pfizer (Details) - Exclusive license agreement - PFIZER $ in Millions	Jul. 11, 2012USD ($)itemshares
License and collaboration agreements
Number of products required from licensor for an agreed upon price \| item	1
One-time cash payment	$ 1.5
Issuance of common stock resulting from private investment in public equity offering, net of issuance costs (in shares) \| shares	192,012
Royalty obligations term	10 years
Maximum
License and collaboration agreements
Eligible amount payable on developmental milestones to Pfizer	$ 2
Additional payable on successful attainment of regulatory and commercial sales milestones	$ 125

License, collaboration and co_5

License, collaboration and commercial agreements - Infinity (Details) - USD ($) $ in Millions	Mar. 05, 2019	Nov. 30, 2016	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Exclusive license agreement \| Infinity
License and collaboration agreements
Payments upon study meeting certain pre-specified criteria		$ 6
Payments on approval of new drug application		$ 22
Royalty obligations term		10 years
Percentage of reduction in royalty on net sales		50.00%
Deduction in royalty payments as percentage of amount paid to third party		50.00%
Percentage royalty reductions capped		50.00%
Percentage of additional royalty on worldwide net sales		4.00%
Percentage of net sales for royalty obligations in the United States		1.00%
Percentage of reduction of royalty rate on basis of non-patent regulatory exclusivity		50.00%
Royalty payments			$ 1.3	$ 1	$ 0.1
Purchase And Sale Agreement Between Infinity and Healthcare Royalty Partners III, L.P. [Member]
License and collaboration agreements
Upfront payment	$ 30
Purchase And Sale Agreement Between Infinity and Healthcare Royalty Partners III, L.P. [Member] \| Maximum
License and collaboration agreements
Potential milestone payment receivable	$ 20

License, collaboration and co_6

License, collaboration and commercial agreements - Sanofi (Details) $ in Thousands	Jul. 25, 2019USD ($)item	Sep. 30, 2020	Aug. 31, 2019USD ($)	Dec. 31, 2020USD ($)	Sep. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2020USD ($)Milestone	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
License and collaboration agreements
Number of days written prior notice required for other party to terminate agreement		5 days
Revenue recognized				$ 506	$ 78,647	$ 4,307	$ 5,056	$ 3,617	$ 9,032	$ 3,136	$ 1,671	$ 88,516	$ 17,456	$ 26,718
License and collaboration revenue
License and collaboration agreements
Revenue recognized					$ 2,818	$ 72	$ 22		$ 5,000	$ 117		2,912	5,117	$ 25,000
License and Collaboration Agreement \| Sanofi
License and collaboration agreements
Proceeds received			$ 5,000									$ 5,000
Maximum aggregate payments entitled to receive if all milestones successfully achieved	$ 42,000
Number of additional milestones achieved \| Milestone												2
Number of material promises \| item	2
Number of performance obligations at outset of the Agreement \| item	1
Number of days written prior notice required for other party to terminate agreement	180 days
Number of days written notice required to terminate agreement if fails to cure breach	60 days
Agreement obligations expire from first commercial sale of product (in years)	10 years
License revenue												$ 2,500
Percentage of future milestone payments and royalties entitled												50.00%
License and Collaboration Agreement \| Sanofi \| License and collaboration revenue
License and collaboration agreements
Revenue recognized													$ 5,000

License, collaboration and co_7

License, collaboration and commercial agreements - Yakult (Details) $ in Thousands

Jun. 05, 2018USD ($)item

Sep. 30, 2020

Jun. 30, 2018USD ($)

Dec. 31, 2020USD ($)

Sep. 30, 2020USD ($)

Jun. 30, 2020USD ($)

Mar. 31, 2020USD ($)

Dec. 31, 2019USD ($)

Sep. 30, 2019USD ($)

Jun. 30, 2019USD ($)

Mar. 31, 2019USD ($)

Dec. 31, 2020USD ($)Milestone

Dec. 31, 2019USD ($)Milestone

Dec. 31, 2018USD ($)

License and collaboration agreements

Number of days written prior notice required for other party to terminate agreement

5 days

Revenue recognized

$ 506

$ 78,647

$ 4,307

$ 5,056

$ 3,617

$ 9,032

$ 3,136

$ 1,671

$ 88,516

$ 17,456

$ 26,718

License and Collaboration Agreement | Yakult

License and collaboration agreements

Proceeds received

$ 10,000

Maximum aggregate payments entitled to receive if all milestones successfully achieved

$ 90,000

Agreement obligations expire from first commercial sale of product (in years)

10 years

Number of days written prior notice required for other party to terminate agreement

180 days

Number of days written notice required to terminate agreement if fails to cure breach

60 days

Number of potential research and development activities | item

Number of material promises | item

Number of performance obligations at outset of the Agreement | item

Number of additional milestones achieved | Milestone

Revenue recognized

$ 10,000

Percentage of future milestone payments and royalties entitled

50.00%

License, collaboration and co_8

License, collaboration and commercial agreements - CSPC (Details) $ in Thousands

Sep. 25, 2018USD ($)item

Sep. 30, 2020

Aug. 31, 2018USD ($)

Dec. 31, 2020USD ($)

Sep. 30, 2020USD ($)

Jun. 30, 2020USD ($)

Mar. 31, 2020USD ($)

Dec. 31, 2019USD ($)

Sep. 30, 2019USD ($)

Jun. 30, 2019USD ($)

Mar. 31, 2019USD ($)

Dec. 31, 2020USD ($)

Dec. 31, 2019USD ($)

Dec. 31, 2018USD ($)

License and collaboration agreements

Revenue recognized

$ 506

$ 78,647

$ 4,307

$ 5,056

$ 3,617

$ 9,032

$ 3,136

$ 1,671

$ 88,516

$ 17,456

$ 26,718

Number of days written prior notice required for other party to terminate agreement

5 days

License and Collaboration Agreement | CSPC

License and collaboration agreements

Proceeds received

$ 15,000

Upfront, non-refundable payment obligation to be received prior to initial Exclusivity Fee

$ 15,000

Maximum aggregate payments entitled to receive if all milestones successfully achieved

$ 160,000

Number of additional milestones achieved

Number of days written notice required to terminate agreement if fails to cure breach

60 days

Number of material promises | item

Number of potential research and development activities | item

Number of performance obligations at outset of the Agreement | item

Revenue recognized

$ 15,000

Agreement obligations expire from first commercial sale of product (in years)

10 years

Number of days written prior notice required for other party to terminate agreement

180 days

Percentage of future milestone payments and royalties entitled

50.00%

Exclusivity Agreement [Member] | CSPC

License and collaboration agreements

Proceeds received

$ 5,000

Restructurings (Details)

Restructurings (Details) $ in Millions	Feb. 27, 2020position	Oct. 28, 2019position	Aug. 31, 2020position	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Restructuring Costs
Restructuring costs				$ 4.6
Selling, general and administrative expenses
Restructuring Costs
Restructuring costs				4.1
Research and development expense.
Restructuring Costs
Restructuring costs				$ 0.5
October 2019 Restructuring \| One-time Termination Benefits
Restructuring Costs
Number of eliminated positions \| position		40
Restructuring costs					$ 1.2
February 2020 Restructuring \| One-time Termination Benefits
Restructuring Costs
Number of eliminated positions \| position	31
August 2020 Restructuring \| One-time Termination Benefits
Restructuring Costs
Number of eliminated positions \| position			41

Restructurings - Restructuring

Restructurings - Restructuring Reserve Activity (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Restructuring Cost and Reserve [Line Items]
Amounts accrued at, December 31, 2019	$ 631
Charges	4,781
Amount Paid	(4,235)
Adjustments	(150)
Amounts accrued at, December 31, 2020	1,027
One-time Termination Benefits \| October 2019 Restructuring
Restructuring Cost and Reserve [Line Items]
Amounts accrued at, December 31, 2019	631
Charges	0
Amount Paid	(626)
Adjustments	(5)
Amounts accrued at, December 31, 2020	0
One-time Termination Benefits \| February 2020 Restructuring
Restructuring Cost and Reserve [Line Items]
Amounts accrued at, December 31, 2019	0
Charges	1,788
Amount Paid	(1,812)
Adjustments	24
Amounts accrued at, December 31, 2020	0
One-time Termination Benefits \| August 2020 Restructuring
Restructuring Cost and Reserve [Line Items]
Amounts accrued at, December 31, 2019	0
Charges	2,993
Amount Paid	(1,797)
Adjustments	(169)
Amounts accrued at, December 31, 2020	$ 1,027

Employee benefit plan (Details)

Employee benefit plan (Details) - USD ($) $ in Millions	12 Months Ended
Employee benefit plan (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Employee benefit plan
Contributions made under 401(k) plan	$ 0.9	$ 1.3	$ 0.8

Quarterly financial informati_3

Quarterly financial information (unaudited, in thousands, except per share data) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue:
Total revenue	$ 506	$ 78,647	$ 4,307	$ 5,056	$ 3,617	$ 9,032	$ 3,136	$ 1,671	$ 88,516	$ 17,456	$ 26,718
Operating expenses:
Cost of sales - product	12	866	392	495	332	371	377	158	1,765	1,238	165
Cost of sales - intangible amortization		8	393	392	393	392	392	392	793	1,569	423
Cost of sales - sale of COPIKTRA license and related assets									31,187
Research and development	10,153	10,955	9,344	10,924	12,455	12,219	11,346	9,758	41,376	45,778	43,648
Selling, general and administrative	7,095	20,614	15,442	19,604	23,728	22,153	29,298	26,033	62,755	101,212	77,265
Total operating expenses	17,260	63,630	25,571	31,415	36,908	35,135	41,413	36,341	137,876	149,797	121,501
(Loss) income from operations	(16,754)	15,017	(21,264)	(26,359)	(33,291)	(26,103)	(38,277)	(34,670)	(49,360)	(132,341)	(94,783)
Other income/(expense)				(1,313)	(641)				(1,313)	(641)	25,556
Interest income	18	19	122	356	611	1,005	1,268	1,497	515	4,381	2,603
Interest expense	(1,354)	(1,898)	(1,868)	(10,674)	(5,453)	(5,041)	(5,185)	(4,929)	(15,794)	(20,608)	(5,810)
Loss on debt extinguishment	(1,580)								(1,580)
Net loss before income taxes	(19,670)	13,138	(23,010)	(37,990)					(67,532)	(149,209)	(72,434)
Income tax expense	(194)								(194)	0	0
Net loss	$ (19,864)	$ 13,138	$ (23,010)	$ (37,990)	$ (38,774)	$ (30,139)	$ (42,194)	$ (38,102)	$ (67,726)	$ (149,209)	$ (72,434)
Net (loss) income per share - basic	$ (0.12)	$ 0.08	$ (0.14)	$ (0.35)	$ (0.51)	$ (0.41)	$ (0.57)	$ (0.52)	$ (0.44)	$ (2)	$ (1.12)
Net (loss) income per share - diluted	$ (0.12)	$ 0.08	$ (0.14)	$ (0.35)	$ (0.51)	$ (0.41)	$ (0.57)	$ (0.52)	$ (0.44)	$ (2)	$ (1.37)
Weighted-average number of common shares used in net loss per share -basic and diluted
Net (loss) income per share-basic (in shares)	169,902	169,510	165,395	108,153	76,331	74,228	73,877	73,854	153,330	74,578	64,962
Net (loss) income per share-diluted (in shares)	169,902	169,760	165,395	108,153	76,331	74,228	73,877	73,854	153,330	74,578	69,321
Product revenue, net
Revenue:
Total revenue	$ 134	$ 5,829	$ 4,235	$ 5,034	$ 3,617	$ 4,032	$ 3,019	$ 1,671	$ 15,232	$ 12,339	$ 1,718
License and collaboration revenue
Revenue:
Total revenue		2,818	$ 72	$ 22		$ 5,000	$ 117		2,912	$ 5,117	$ 25,000
Copiktra license and related assets
Revenue:
Total revenue		70,000							70,000
Operating expenses:
Cost of sales - sale of COPIKTRA license and related assets		$ 31,187
Transition Services Revenue
Revenue:
Total revenue	$ 372								$ 372