Verastem (VSTM) 10-Q 9 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Nov. 06, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 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
Trading Symbol	VSTM
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		169,774,432
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001526119
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 170,470	$ 43,514
Short-term investments		31,992
Accounts receivable, net	5,685	2,524
Inventory		3,096
Restricted cash	9,367	507
Prepaid expenses and other current assets	3,033	3,328
Total current assets	188,555	84,961
Property and equipment, net	497	947
Right-of-use asset, net	2,820	3,077
Intangible assets, net		20,008
Restricted cash	25,875	35,241
Other assets	23	812
Total assets	217,770	145,046
Current liabilities:
Accounts payable	4,681	9,655
Accrued expenses	23,164	19,365
Lease liability, short-term	533	420
Derivative liability, short-term		450
Current portion of long-term debt	9,300
Total current liabilities	37,678	29,890
Non-current liabilities:
Long-term debt	26,397	35,067
Convertible senior notes	20,841	68,556
Lease liability, long-term	3,081	3,489
Other non-current liabilities		870
Total liabilities	87,997	137,872
Stockholders' equity:
Preferred stock, $0.0001 par value; 5,000 shares authorized, no shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively
Common stock, $0.0001 par value; 300,000 and 200,000 shares authorized, 169,540 and 80,118 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively	17	8
Additional paid-in capital	702,403	531,937
Accumulated other comprehensive income		14
Accumulated deficit	(572,647)	(524,785)
Total stockholders' equity	129,773	7,174
Total liabilities and stockholders' equity	$ 217,770	$ 145,046

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares shares in Thousands	Sep. 30, 2020	Dec. 31, 2019
CONDENSED 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	169,540	80,118
Common stock, shares outstanding	169,540	80,118

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Total revenue	$ 78,647	$ 9,032	$ 88,010	$ 13,840
Operating expenses:
Cost of sales - product	866	371	1,753	906
Cost of sales - intangible amortization	8	392	793	1,177
Cost of sales - sale of COPIKTRA license and related assets	31,187		31,187
Research and development	10,955	12,219	31,223	33,322
Selling, general and administrative	20,614	22,153	55,660	77,484
Total operating expenses	63,630	35,135	120,616	112,889
Income (loss) from operations	15,017	(26,103)	(32,606)	(99,049)
Other expense			(1,313)
Interest income	19	1,005	497	3,770
Interest expense	(1,898)	(5,041)	(14,440)	(15,156)
Net income (loss)	$ 13,138	$ (30,139)	$ (47,862)	$ (110,435)
Net income (loss) per share-basic	$ 0.08	$ (0.41)	$ (0.32)	$ (1.49)
Net income (loss) per share-diluted	$ 0.08	$ (0.41)	$ (0.32)	$ (1.49)
Weighted average common shares outstanding used in computing:
Net income (loss) per share-basic (in shares)	169,510	74,228	147,766	73,988
Net income (loss) per share-diluted (in shares)	169,760	74,228	147,766	73,988
Net income (loss)	$ 13,138	$ (30,139)	$ (47,862)	$ (110,435)
Unrealized (loss) gain on available-for-sale securities		(59)	(14)	(100)
Comprehensive loss	13,138	(30,198)	(47,876)	(110,535)
Product revenue, net
Revenue:
Total revenue	5,829	4,032	15,098	8,722
License and collaboration revenue
Revenue:
Total revenue	2,818	$ 5,000	2,912	$ 5,118
Copiktra license and related assets
Revenue:
Total revenue	$ 70,000		$ 70,000

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common stockPrivate Investment in Public Equity (PIPE)	Common stockAt-the-market equity offering program	Common stock	Additional paid-in capitalPrivate Investment in Public Equity (PIPE)	Additional paid-in capitalAt-the-market equity offering program	Additional paid-in capital	Accumulated other comprehensive (loss) income	Accumulated deficit	Private Investment in Public Equity (PIPE)	At-the-market equity offering program	Total
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 income (loss)								(38,102)			(38,102)
Unrealized (loss) on available-for-sale marketable securities							(17)				(17)
Issuance of common stock resulting from exercise of stock options						75					75
Issuance of common stock resulting from exercise of stock options (in shares)			46,803
Issuance of common stock resulting from vesting of restricted stock units						(43)					(43)
Issuance of common stock resulting from vesting of restricted stock units (in shares)			23,792
Stock-based compensation expense						2,248					2,248
Balance at Mar. 31, 2019			$ 7			502,021	110	(413,678)			88,460
Balance (in shares) at Mar. 31, 2019			73,876,939
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 income (loss)											(110,435)
Unrealized (loss) on available-for-sale marketable securities											(100)
Balance at Sep. 30, 2019			$ 7			507,494	27	(486,011)			21,517
Balance (in shares) at Sep. 30, 2019			74,313,744
Balance at Mar. 31, 2019			$ 7			502,021	110	(413,678)			88,460
Balance (in shares) at Mar. 31, 2019			73,876,939
Increase (Decrease) in Stockholders' Equity
Net income (loss)								(42,194)			(42,194)
Unrealized (loss) on available-for-sale marketable securities							(24)				(24)
Stock-based compensation expense						3,065					3,065
Balance at Jun. 30, 2019			$ 7			505,086	86	(455,872)			49,307
Balance (in shares) at Jun. 30, 2019			73,876,939
Increase (Decrease) in Stockholders' Equity
Net income (loss)								(30,139)			(30,139)
Unrealized (loss) on available-for-sale marketable securities							(59)				(59)
Issuance of common stock resulting from exercise of stock options						54					54
Issuance of common stock resulting from exercise of stock options (in shares)			45,104
Issuance of common stock resulting from vesting of restricted stock units (in shares)			50,000
Stock-based compensation expense						1,915					1,915
Issuance of common stock under Employee Stock Purchase Plan						439					439
Issuance of common stock under Employee Stock Purchase Plan (in shares)			341,701
Balance at Sep. 30, 2019			$ 7			507,494	27	(486,011)			21,517
Balance (in shares) at Sep. 30, 2019			74,313,744
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 income (loss)								(37,990)			$ (37,990)
Unrealized (loss) on available-for-sale marketable securities							(5)				(5)
Issuance of common stock resulting from exercise of stock options						983					983
Issuance of common stock resulting from exercise of stock options (in shares)			645,628
Issuance of common stock resulting from vesting of restricted stock units						(51)					(51)
Issuance of common stock resulting from vesting of restricted stock units (in shares)			58,166
Stock-based compensation expense						1,370					1,370
Issuance of common stock, net of issuance costs	$ 5			$ 93,824					$ 93,829
Issuance of common stock, net of issuance costs (in shares)	46,511,628
Issuance of common stock under Employee Stock Purchase Plan						259					259
Issuance of common stock under Employee Stock Purchase Plan (in shares)			227,141
Conversion of 2019 Notes into common stock			$ 3			57,411					57,414
Conversion of 2019 Notes into common stock (in shares)			34,796,350
Balance at Mar. 31, 2020			$ 16			685,733	9	(562,775)			122,983
Balance (in shares) at Mar. 31, 2020			162,356,444
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 income (loss)											$ (47,862)
Unrealized (loss) on available-for-sale marketable securities											(14)
Issuance of common stock, net of issuance costs (in shares)		6,769,559
Balance at Sep. 30, 2020			$ 17			702,403		(572,647)			$ 129,773
Balance (in shares) at Sep. 30, 2020			169,540,447								169,540,000
Balance at Mar. 31, 2020			$ 16			685,733	9	(562,775)			$ 122,983
Balance (in shares) at Mar. 31, 2020			162,356,444
Increase (Decrease) in Stockholders' Equity
Net income (loss)								(23,010)			(23,010)
Unrealized (loss) on available-for-sale marketable securities							$ (9)				(9)
Issuance of common stock resulting from exercise of stock options						551					551
Issuance of common stock resulting from exercise of stock options (in shares)			179,266
Issuance of common stock resulting from vesting of restricted stock units						(31)					(31)
Issuance of common stock resulting from vesting of restricted stock units (in shares)			32,650
Stock-based compensation expense						1,659					1,659
Issuance of common stock, net of issuance costs		$ 1			$ 12,229					$ 12,230
Issuance of common stock, net of issuance costs (in shares)		6,769,559
Balance at Jun. 30, 2020			$ 17			700,141		(585,785)			114,373
Balance (in shares) at Jun. 30, 2020			169,337,919
Increase (Decrease) in Stockholders' Equity
Net income (loss)								13,138			13,138
Issuance of common stock resulting from vesting of restricted stock units						(42)					(42)
Issuance of common stock resulting from vesting of restricted stock units (in shares)			71,476
Stock-based compensation expense						2,156					2,156
Issuance of common stock, net of issuance costs (in shares)		0
Issuance of common stock under Employee Stock Purchase Plan						148					148
Issuance of common stock under Employee Stock Purchase Plan (in shares)			131,052
Balance at Sep. 30, 2020			$ 17			$ 702,403		$ (572,647)			$ 129,773
Balance (in shares) at Sep. 30, 2020			169,540,447								169,540,000

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2020	Mar. 31, 2020
Private Investment in Public Equity (PIPE)
Issuance of common stock, issuance costs		$ 6,171
At-the-market equity offering program
Issuance of common stock, issuance costs	$ 55

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities
Net loss	$ (47,862)	$ (110,435)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	450	335
Amortization of acquired intangible asset	793	1,177
Amortization of right-of-use asset and lease liability	(38)	154
Stock-based compensation expense	5,185	7,228
Amortization of deferred financing costs, debt discounts and premiums and discounts on available-for-sale marketable securities	9,765	4,426
Change in fair value of interest make whole provision for 2019 Notes	1,313
Changes in operating assets and liabilities:
Accounts receivable, net	(3,161)	(1,897)
Inventory	3,096	(151)
Prepaid expenses, other current assets and other assets	1,084	(1,100)
Accounts payable	(4,974)	(1,411)
Accrued expenses and other liabilities	3,951	7
Other long-term liabilities	(870)	370
Intangible assets & property, plant and equipment	19,465
Net cash used in operating activities	(11,803)	(101,297)
Investing activities
Purchases of property and equipment	(33)	(7)
Purchases of investments		(73,186)
Maturities of investments	32,050	137,680
Net cash provided by investing activities	32,017	64,487
Financing activities
Proceeds from long-term debt, net of issuance costs		9,694
Proceeds from the exercise of stock options and employee stock purchase program	1,940	569
Interest make-whole payments on the 2019 Notes	(1,763)
Proceeds from the issuance of common stock, net	106,059
Net cash provided by financing activities	106,236	10,263
Increase (decrease) in cash, cash equivalents and restricted cash	126,450	(26,547)
Cash, cash equivalents and restricted cash at beginning of period	79,262	130,608
Cash, cash equivalents and restricted cash at end of period	205,712	104,061
Supplemental disclosure of non-cash investing and financing activities
Common stock issuance costs included in accounts payable and accrued expenses	15	$ 15
Conversion of 2019 Notes into common stock	57,414
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	$ 124

Nature of business

Nature of business	9 Months Ended
	Sep. 30, 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, including RAF/MEK inhibition and focal adhesion kinase (FAK) inhibition. The Company’s product candidates, defactinib and VS-6766 (formerly known as CH5126766, CK127, and RO5126766), are being investigated for treatment of various solid tumors. The Company is currently developing its product candidates in both preclinical and clinical studies as potential therapies for certain cancers, including, ovarian cancer, lung cancer, colorectal cancer, pancreatic cancer, and mesothelioma. The Company believes that these compounds may be beneficial as therapeutics either as single agents or when used in combination with immuno-oncology agents , On September 24, 2018, the Company’s first commercial product, COPIKTRA® (duvelisib), was approved by the U.S. Food and Drug Administration (the FDA) for the treatment of adult patients with certain hematologic cancers including relapsed or refractory chronic lymphocytic leukemia/ small lymphocytic lymphoma (CLL/SLL) after at least two prior therapies and relapsed or refractory follicular lymphoma (FL) after at least two prior systemic therapies. On August 10, 2020, the Company and Secura Bio, Inc. (Secura) entered into an asset purchase agreement (Secura APA). Pursuant to the Secura APA, the Company sold to Secura its exclusive worldwide license, including certain related assets for the research, development, commercialization, and manufacture in oncology indications of products containing COPIKTRA (duvelisib). The transaction closed on September 30, 2020. Refer to Note 16. License and collaboration agreements The condensed 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 September 30, 2020, the Company had cash, cash equivalents, restricted cash and short-term 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.

Summary of significant accounti

Summary of significant accounting policies	9 Months Ended
	Sep. 30, 2020
Summary of significant accounting policies
Summary of significant accounting policies	2. Summary of significant accounting policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with generally accepted accounting principles in the United States (GAAP) for interim financial reporting and as required by Regulation S-X, Rule 10-01 under the assumption that the Company will continue as a going concern for the next twelve months. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements, or any adjustments that might result from the uncertainty related to the Company’s ability to continue as a going concern. In the opinion of management, all adjustments (including those which are normal and recurring) considered necessary for a fair presentation of the interim financial information have been included. When preparing financial statements in conformity with GAAP, the Company must make estimates and assumptions that affect the reported amounts and related disclosures at the date of the financial statements. Actual results could differ from those estimates. Additionally, operating results for the three and nine months ended September 30, 2020 are not necessarily indicative of the results that may be expected for any other interim period or for the year ending December 31, 2020. For further information, refer to the financial statements and footnotes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019, as filed with the Securities and Exchange Commission (SEC) on March 11, 2020. Significant Accounting Policies Revenue Recognition Revenue from Contracts with Customers Product Revenue, Net Product Revenue, Net – to community hospitals or oncology clinics with in-office dispensaries who in turn distribute COPIKTRA to patients. In addition to distribution agreements with customers, the Company also entered into arrangements with (1) certain government agencies and various private organizations (Third-Party Payers), which may provide for chargebacks or discounts with respect to the purchase of COPIKTRA, and (2) Medicare and Medicaid, which may provide for certain rebates with respect to the purchase of COPIKTRA. 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 three and nine months ended September 30, 2020, 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 condensed consolidated statements of operations and comprehensive income (loss) for the three and nine months ended September 30, 2020. 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 condensed consolidated statements of operations and comprehensive income (loss) for the three and nine months ended September 30, 2020. 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 condensed 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 condensed 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 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 Concentrations of credit risk and off-balance sheet risk Cash, cash equivalents, short-term 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 September 30, 2020, the Company’s cash, cash equivalents and short-term investments were deposited at two 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 September 30, 2020 there were two customers that cumulatively made up more than 60% 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 each of the three and nine months ended September 30, 2020, there were three and four customers, respectively who each individually accounted for greater than 10% of the Company’s total product revenue, net and license and collaboration revenue. 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 condensed 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 condensed 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 condensed 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 condensed 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 of 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 of disclosures.

Cash, cash equivalents and rest

Cash, cash equivalents and restricted cash	9 Months Ended
	Sep. 30, 2020
Cash, cash equivalents and restricted cash
Cash, cash equivalents and restricted cash	3. Cash, cash equivalents and restricted cash The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the condensed consolidated balance sheets that sum to the total of the same such amounts shown in the condensed consolidated statements of cash flows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 Cash and cash equivalents ​ $ 170,470 ​ $ 43,514 Restricted cash ​ 35,242 ​ 35,748 Total cash, cash equivalents and restricted cash ​ $ 205,712 ​ $ 79,262 ​ Amounts included in restricted cash as of September 30, 2020 and December 31, 2019 represent (i) cash that the Company is contractually obligated to maintain in accordance with the terms of the Amended Term Loan Agreement, (ii) cash received pursuant to a funded research and development agreement with the Leukemia and Lymphoma Society (the LLS Research Funding Agreement) which is restricted for future expenditures for specific R&D studies and (iii) cash held to collateralize outstanding letters of credit provided as a security deposit for the Company’s office space located in Needham, Massachusetts in the amount of approximately $35.0 million, $0.0 million, and $0.2 million respectively, at September 30, 2020 and $35.0 million, $0.5 million, and $0.2 million, respectively, at December 31, 2019. Restricted cash related to Amended Term Loan Agreement is included on the condensed balance sheet at September 30, 2020 in the amount of $9.4 million in current restricted cash and $25.6 million in non-current restricted cash. Restricted cash related to the Amended Term Loan Agreement is segregated between current restricted cash and non-current restricted cash in correlation to the segregation of the Amended Term Loan Agreement between current and non-current at September 30, 2020. Restricted cash related to Amended Term Loan Agreement is included on the condensed balance sheet at December 31, 2019 in non-current restricted cash. Letters of credit are included in non-current restricted cash on the condensed consolidated balance sheets at September 30, 2020 and December 31, 2019, and cash related to the LLS Research Funding Agreement is included in current restricted cash on the condensed consolidated balance sheet at December 31, 2019.

Fair value of financial instrum

Fair value of financial instruments	9 Months Ended
	Sep. 30, 2020
Fair value of financial instruments
Fair value of financial instruments	4. 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): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 Description Total Level 1 Level 2 Level 3 Financial assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents ​ $ 131,693 ​ $ 131,693 ​ $ — ​ $ — ​ Total financial assets ​ $ 131,693 ​ $ 131,693 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 ​ ​ The Company’s cash equivalents and short-term investments consist of U.S. Government money market funds, corporate bonds, agency bonds and commercial paper of publicly traded companies. The investments and cash equivalents have been initially valued at the transaction price and subsequently valued, at the end of each reporting period, utilizing third party pricing services or other market observable data. The pricing services utilize industry standard valuation models, including both income and market-based approaches and observable market inputs to determine value. These observable market inputs include reportable trades, benchmark yields, credit spreads, broker/dealer quotes, bids, offers, current spot rates and other industry and economic events. The Company validates the prices provided by third party pricing services by reviewing their pricing methods and matrices, obtaining market values from other pricing sources, analyzing pricing data in certain instances and confirming that the relevant markets are active. After completing its validation procedures, the Company did not adjust or override any fair value measurements provided by the pricing services as of September 30, 2020 and December 31, 2019. During 2019, a derivative liability was recorded as a result of the issuance of the 2019 Notes (see Note 12. Convertible Senior Notes The fair value of the derivative liability was determined using a Monte-Carlo simulation by calculating fair value of the 2019 Interest Make-Whole Payment to 2019 Note holders based on assumed timing of conversion of the 2019 Notes. At December 31, 2019, the risk-adjusted discount rate was determined to be The following table represents a reconciliation of the derivative liability recorded in connection with the issuance of the 2019 Notes (in thousands): ​ ​ ​ ​ January 1, 2020 ​ $ 450 Fair value adjustment ​ ​ 1,313 Derivative liability extinguished upon conversion ​ (1,763) September 30, 2020 ​ $ — ​ 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 condensed consolidated balance sheet dates. The carrying value of the Company’s long-term debt, including the current portion, at September 30, 2020 and December 31, 2019 was approximately $35.7 million and $35.1 million, respectively. The Company estimates that the fair value of its long-term debt, including the current portion, was approximately $37.0 million at both September 30, 2020 and December 31, 2019. The fair value of the Company’s long-term debt was determined using Level 3 inputs. The fair value of the Company’s 5.00% Convertible Senior Notes due 2048 (the 2018 Notes) as of September 30, 2020 was approximately $10.0 million, which differs from the carrying value of the 2018 Notes of $20.8 million. The fair value of the 2018 Notes was determined using Level 2 inputs.

Investments

Investments	9 Months Ended
	Sep. 30, 2020
Investments
Investments	5. Investments Cash, cash equivalents, restricted cash and short-term investments consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ Gross Gross ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair ​ Cost Gains Losses Value Cash, cash equivalents & restricted cash: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and money market accounts ​ $ 205,712 ​ $ — ​ $ — ​ $ 205,712 ​ Total cash, cash equivalents & restricted cash: ​ $ 205,712 ​ $ — ​ $ — ​ $ 205,712 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 ​ ​ There were no realized gains or losses on investments for the three and nine months ended September 30, 2020 or 2019, respectively. There were 12 months. The fair value of these securities as of September 30, 2020 and December 31, 2019 was $0 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 September 30, 2020 and December 31, 2019, respectively.

Inventory

Inventory	9 Months Ended
	Sep. 30, 2020
Inventory
Inventory	6. Inventory ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 Raw materials ​ $ — ​ $ 955 ​ Work in process ​ — ​ 2,040 ​ Finished goods ​ — ​ 101 ​ Total inventories ​ $ — ​ $ 3,096 ​ ​ Note 16. License and collaboration agreements ​

Intangible assets

Intangible assets	9 Months Ended
	Sep. 30, 2020
Intangible assets
Intangible assets	7. Intangible assets million milestone payment which became payable upon the FDA marketing approval 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 and collaboration agreements

Accrued expenses

Accrued expenses	9 Months Ended
	Sep. 30, 2020
Accrued expenses
Accrued expenses	8. Accrued expenses Accrued expenses consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 Compensation and related benefits ​ 8,078 ​ 7,399 ​ Contract research organization costs ​ ​ 6,423 ​ ​ 5,467 ​ Commercialization costs ​ 2,707 ​ 3,028 ​ Interest ​ ​ 874 ​ ​ 897 ​ Consulting fees ​ 3,283 ​ 1,610 ​ Professional fees ​ 882 ​ 573 ​ Other ​ 917 ​ 391 ​ Total accrued expenses ​ $ 23,164 ​ $ 19,365 ​ ​

Product revenue reserves and al

Product revenue reserves and allowances	9 Months Ended
	Sep. 30, 2020
Product revenue reserves and allowances
Product revenue reserves and allowances	9. Product revenue reserves and allowances ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Third-Party ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Trade ​ Payer ​ Government ​ ​ ​ ​ ​ ​ ​ ​ discounts ​ chargebacks, ​ rebates and ​ ​ ​ ​ ​ ​ ​ ​ and ​ discounts ​ other ​ ​ ​ ​ ​ ​ ​ allowances and fees incentives Returns Total Balance at December 31, 2019 ​ $ 111 ​ $ 255 ​ $ 372 ​ $ 76 ​ $ 814 Provision related to sales in the current year ​ 626 ​ 1,846 ​ 673 ​ 377 ​ 3,522 Adjustments related to prior period sales ​ — ​ — ​ — ​ — ​ — Credits and payments made ​ (590) ​ (1,805) ​ (725) ​ (327) ​ (3,447) Ending balance at September 30, 2020 ​ $ 147 ​ $ 296 ​ $ 320 ​ $ 126 ​ $ 889 ​ Trade discounts and Third-Party Payer chargebacks and discounts are recorded as a reduction to accounts receivable, net on the condensed 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 condensed consolidated balance sheets.

Leases

Leases	9 Months Ended
	Sep. 30, 2020
Leases
Leases	10. 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. 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 May 2025. Pursuant to the Amended Lease Agreement, the initial annual base rent amount is approximately $0.7 million, 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 condensed 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 Topic 842, Leases of January 1, 2019. 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 September 30, 2020, a right-of-use asset of $2.8 million and lease liability of $3.6 million are reflected on the condensed consolidated balance sheets. The elements of lease expense were as follows (dollar amounts in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 Lease Expense ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease expense ​ ​ $ 221 ​ $ 222 ​ $ 664 ​ $ 666 Total Lease Expense ​ ​ $ 221 ​ $ 222 ​ $ 664 ​ $ 666 Other Information - Operating Leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows paid for amounts included in measurement of lease liabilities ​ ​ $ 252 ​ $ 180 ​ $ 703 ​ $ 512 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 Other Balance Sheet Information - Operating Leases ​ ​ ​ ​ Weighted average remaining lease term (in years) ​ ​ ​ 4.8 Weighted average discount rate ​ ​ ​ 14.6% Maturity Analysis ​ ​ ​ ​ 2020 ​ ​ $ 252 2021 ​ ​ ​ 1,019 2022 ​ ​ ​ 1,039 2023 ​ ​ ​ 1,060 2024 ​ ​ ​ 1,081 Thereafter ​ ​ ​ 546 Total ​ ​ $ 4,997 Less: Present value discount ​ ​ ​ (1,383) Lease Liability ​ ​ $ 3,614 ​

Long-term debt

Long-term debt	9 Months Ended
	Sep. 30, 2020
Long-term debt
Long-term debt	11. 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. As of September 30, 2020, the Company has borrowed a total of $35.0 million in term loans. The Company must 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). As of September 30, 2020, the Company has not met the Initial Net Product Revenue Threshold. Due to the Secura sale discussed below in Note 16. License and collaboration agreements, million in current restricted cash and non-current restricted cash on the condensed consolidated balance sheets. As the Initial Net Product Revenue Threshold is not possible of achievement, the Company must, on a monthly basis, either (a) maintain at all times during such month unrestricted and unencumbered cash in accounts subject to control agreements in favor of Hercules, in an aggregate amount greater than or equal to The Amended Term Loan will mature on December 1, 2022 (Amended Term Loan Maturity Date). Each advance accrues 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 provides for interest-only payments until April 1, 2021, which may be 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. Thereafter, amortization payments will be payable monthly in equal installments of principal and interest (subject to recalculation upon a change in prime rates). The Amended Term Loan is 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. On the Fourth Amendment Date, the Company was required to pay any outstanding accrued interest as well as the final payment fee equal to 4.5% on the outstanding principal balance, or $1.1 million. No prepayment charges were due as a result of executing the Fourth Amendment or conversion of the existing term loans into Amended Term A Loans. The events of default under the Amended Loan Agreement include, without limitation, and subject to customary grace periods, (i) any failure by us to make any payments of principal or interest under the Amended Loan Agreement, any promissory notes or any other loan documents, (ii) any breach or default in the performance of any covenant under the Amended Loan Agreement, (iii) any making of false or misleading representations or warranties in any material respect, (iv) the Company’s insolvency or bankruptcy, (v) certain attachments or judgments on the assets of Verastem, Inc., or (vi) the occurrence of any material default under certain agreements or obligations of ours involving indebtedness, or (vii) the occurrence of a material adverse effect. If an event of default occurs, Hercules is entitled to take enforcement action, including acceleration of amounts due under the Amended Loan Agreement. The Amended Loan Agreement also contains other customary provisions, such as expense reimbursement and confidentiality. Hercules has indemnification rights and the right to assign the Amended Term Loan. 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 condensed 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 September 30, 2020. ​ ​ ​ ​ ​ 2021 ​ $ 14,234 2022 ​ ​ 20,766 Total principal payments ​ $ 35,000 ​

Convertible Senior Notes

Convertible Senior Notes	9 Months Ended
	Sep. 30, 2020
Convertible Senior Notes
Convertible Senior Notes	12. Convertible Senior Notes Convertible Senior Notes due 2048 (the 2018 Notes). The 2018 Notes are governed by the terms of a base indenture for senior debt securities (the 2018 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, as trustee. The 2018 Notes are senior unsecured obligations of the Company and bear interest at a rate of

Common stock

Common stock	9 Months Ended
	Sep. 30, 2020
Common stock.
Common stock	13. Common stock Private Investment in Public Equity (PIPE) At-the-market equity offering programs In March 2017, the Company established an at-the-market equity offering program 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 Fitzgerald & Co. (Cantor) as sales agent. In August 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 at-the-market equity offering program to $75.0 million. During the three and nine months ended September 30, 2020, the Company sold 0 shares and 6,769,559 shares, respectively under this program for net proceeds of approximately $0 million and $12.2 million, respectively (after deducting commissions and other offering expenses). Through September 30, 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).

Stock-based compensation

Stock-based compensation	9 Months Ended
	Sep. 30, 2020
Stock-based compensation
Stock-based compensation	14. Stock-based compensation Stock options A summary of the Company’s stock option activity and related information for the nine months ended September 30, 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 621,357 ​ $ 1.92 ​ ​ ​ ​ ​ ​ Exercised (824,894) ​ $ 1.86 ​ ​ ​ ​ ​ ​ Forfeited/cancelled (4,142,720) ​ $ 3.97 ​ ​ ​ ​ ​ ​ Outstanding at September 30, 2020 12,912,267 ​ $ 4.04 6.5 ​ $ 11 ​ Vested at September 30, 2020 8,562,159 ​ $ 4.75 5.6 ​ $ 10 ​ Vested and expected to vest at September 30, 2020(1) 12,702,267 ​ $ 4.07 6.5 ​ $ 11 ​ (1) This represents the number of vested options as of September 30, 2020, plus the number of unvested options expected to vest as of September 30, 2020. The fair value of each stock option granted during the nine months ended September 30, 2020 and 2019 was estimated on the grant date using the Black-Scholes option-pricing model using the following weighted-average assumptions: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ ​ 2020 ​ 2019 Risk-free interest rate 0.75 % ​ 2.10 % Volatility 94 % ​ 86 % Dividend yield — ​ ​ — ​ Expected term (years) 5.8 ​ ​ 5.8 ​ ​ Restricted stock units (RSUs) The Company awards RSUs to employees under its Amended and Restated 2012 Incentive Plan and its 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, (ii) 100 percent on the first anniversary of the vesting commencement date, (iii) thirty three and one-third percent ( 33 1/3% A summary of RSU activity during the nine months ended September 30, 2020 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shares Weighted-average grant date fair value per share Outstanding at December 31, 2019 ​ 678,089 ​ $ 2.36 ​ Granted ​ 3,825,007 ​ $ 1.56 ​ Vested ​ (595,289) ​ $ 2.25 ​ Forfeited/cancelled ​ ​ (149,259) ​ $ 2.69 ​ Outstanding at September 30, 2020 ​ 3,758,548 ​ $ 1.55 ​ ​ Note 19 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 following weighted-average assumptions: ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, ​ 2020 ​ 2019 Risk-free interest rate 1.04 % ​ 2.26 % Volatility 109 % ​ 88 % Dividend yield — ​ ​ — ​ Expected term (years) 0.5 ​ ​ 0.5 ​ ​

Net income (loss) per share

Net income (loss) per share	9 Months Ended
	Sep. 30, 2020
Net income (loss) per share
Net income (loss) per share	15. Net income (loss) per share Basic net income (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 employee stock purchase plan shares (using the “treasury stock” method), and the 2018 Notes and 2019 Notes (using the “if-converted” method), unless their effect on net loss per share is anti-dilutive. The computation of basic and diluted net income (loss) per share attributable to common stockholders consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ 2020 2019 2020 2019 Numerator ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) 13,138 (30,139) ​ (47,862) (110,435) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average shares outstanding - basic ​ 169,510 ​ 74,228 ​ 147,766 ​ 73,988 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effect of dilutive securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ Restricted Stock Units ​ 137 ​ - ​ - ​ - ​ Stock Options ​ 86 ​ - ​ - ​ - ​ Employee Stock Purchase Plan ​ 27 ​ - ​ - ​ - ​ Weighted average shares outstanding - diluted ​ 169,760 ​ 74,228 ​ 147,766 ​ 73,988 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) per share - basic ​ 0.08 ​ (0.41) ​ (0.32) ​ (1.49) ​ Net income (loss) per share - diluted ​ 0.08 ​ (0.41) ​ (0.32) ​ (1.49) ​ ​ The following potentially dilutive securities were excluded from the calculation of diluted net income (loss) per share for the periods indicated because including them would have had an anti-dilutive effect: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ 2020 2019 2020 2019 Outstanding stock options 11,613,978 16,493,690 ​ 12,912,267 16,493,690 ​ Outstanding restricted stock units ​ 807,566 ​ 816,959 ​ 3,758,548 ​ 816,959 ​ 2018 Notes ​ 3,950,032 ​ 20,936,548 ​ 3,950,032 ​ 20,936,548 ​ Employee Stock Purchase Plan ​ — ​ 262,852 ​ 105,533 ​ 262,852 ​ Total potentially dilutive securities 16,371,576 38,510,049 ​ 20,726,380 38,510,049 ​ ​

License and collaboration agree

License and collaboration agreements	9 Months Ended
	Sep. 30, 2020
License and collaboration agreements
License and collaboration agreements	16. License and collaboration 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. Pursuant to the terms of the Secura APA, Secura has agreed to pay the Company (i) an up-front payment of $70.0 million which was paid to the Company in September 2020, (ii) 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, (iii) 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, (c) 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 (d) 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 our 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 three and nine months ended September 30, 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 within the statements of operations and comprehensive income (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. Pro Forma Financial Information The following pro forma financial information reflects the consolidated results of operations of the Company as if the duvelisib sale to Secura had taken place on January 1, 2019. The pro forma financial information is not necessarily indicative of the results of operations as they would have been had the transaction been effected on the assumed date. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ 2020 2019 2020 2019 Net revenue 1,250 ​ 2,500 ​ 1,250 ​ 2,500 Net loss (13,308) ​ (13,394) ​ (52,551) ​ (48,915) ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss per share—basic ​ (0.08) ​ (0.18) ​ (0.36) ​ (0.66) Net loss per share—diluted ​ (0.08) ​ (0.18) ​ (0.36) ​ (0.66) ​ The pro forma statements include adjustments to eliminate the direct operating results attributable to duvelisib as if the duvelisib sale to Secura occurred on January 1, 2019. The adjustments include elimination of all product revenue, net, sale of COPIKTRA license and related assets revenue, cost of sales – product, cost of sales – intangible amortization, and cost of sales – sale of COPIKTRA license and related assets which were solely and directly related to duvelisib. The adjustments include removing license and collaboration revenue the Company would not have earned if the duvelisib sale had taken place January 1, 2019. Net revenue for the three and nine months ended September 30, 2020 includes $1.3 million or 50% of the $2.5 million milestone earned by Sanofi. Net revenue for the three and nine months ended September 30, 2019 includes $2.5 million or 50% of the $5.0 million upfront received in connection with entering into the license and collaboration agreement with Sanofi. Adjustments to research and development, and selling, general and administrative expenses include amounts that are directly related to duvelisib. The pro forma adjustments do not include any adjustments to other expense, interest income or interest expense. Nonrecurring pro forma transaction costs directly attributable to the Secura transaction were approximately $3.5 million for the three and nine month period ended September 30, 2020 and have been deducted from the net loss above. With respect to selling, general and administrative expenses the Company has adjusted the direct expenses associated with duvelisib, including commercial activities . With respect to research and development expenses, the Company allocates the expenses related to external research and development services, such as contract research organizations, clinical sites, manufacturing organizations and consultants by project. The Company uses our employee and infrastructure resources across multiple research and development projects. The Company’s project costing methodology does not allocate personnel and other indirect costs to specific clinical programs. Accordingly, for both selling, general and administrative and research and development expenses, the pro forma adjustments do not include adjustments for allocations of indirect operating costs as these costs are deployed across multiple programs not directly related to duvelisib. In addition, the Company has not included any allocations of anticipated savings due to costs that may be reduced or eliminated. 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 ) 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. For the three and nine months ended September 30, 2020, the Company recognized $2.5 million of license revenue upon achievement of two development milestones in the three month period ended September 30, 2020. As discussed above as of September 30, 2020, Secura has assumed from the Company all responsibilities and obligations under the Sanofi Agreement. After September 30, 2020, the Company is entitled to 50% of future milestone payments and royalties pursuant to the Secura APA discussed under heading Secura Bio, Inc. (Secura) Yakult Honsha Co., Ltd. (Yakult) On June 5, 2018, the Company entered into a license and collaboration agreement with Yakult (the Yakult Agreement), 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. 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 on a pro-rata basis. For the nine months ended September 30, 2020, there have been no additional milestones achieved under the Yakult Agreement. As discussed above as of September 30, 2020, Secura has assumed from the Company all responsibilities and obligations under the Yakult Agreement. After September 30, 2020, the Company is entitled to 50% of future milestone payments and royalties pursuant to the Secura APA discussed under heading Secura Bio, Inc. (Secura) CSPC Pharmaceutical Group Limited (CSPC) 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 (each, a Region and collectively, the CSPC Territory) for the treatment, prevention, palliation or diagnosis of all oncology indications in humans. CSPC paid the Company an aggregate upfront, non-refundable payment of $15.0 million in 2018. 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, subject to reduction in certain circumstances, and to fund certain global development costs related to worldwide clinical trials conducted by the Company in which CSPC has opted to participate on a pro-rata basis. For the nine months ended September 30, 2020 there have been no additional milestones achieved under the CSPC Agreement. As discussed above as of September 30, 2020, Secura has assumed from the Company all responsibilities and obligations under the CSPC Agreement. After September 30, 2020, the Company is entitled to 50% of future milestone payments and royalties pursuant to the Secura APA discussed under heading Secura Bio, Inc. (Secura)

Income taxes

Income taxes	9 Months Ended
	Sep. 30, 2020
Income taxes
Income taxes	17. Income taxes

Commitments and contingencies

Commitments and contingencies	9 Months Ended
	Sep. 30, 2020
Commitments and contingencies
Commitments and contingencies	18. Commitments and contingencies The Company has no other commitments other than minimum lease payments as disclosed in Note 10. Leases.

Restructurings

Restructurings	9 Months Ended
	Sep. 30, 2020
Restructurings
Restructurings	19. 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 defactinib and CH5126766, 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 three and nine months ended September 30, 2020, the Company recorded an aggregate expense of $3.0 million and $4.8 million, respectively, which is reflected in the condensed consolidated statements of operation and comprehensive income (loss) as selling general, and administrative expense for $2.9 million and $4.3 million, respectively, and research and development expense for $0.1 million and $0.5 million, respectively, for the February 2020 Restructuring and August 2020 Restructuring for one-time termination benefits for employee severance, benefits, and related costs. The following table summarizes the accrued liabilities activity recorded in connection with the restructurings for the nine months ended September 30, 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 ​ ​ (1,653) ​ ​ 10 ​ ​ 145 August 2020 Restructuring ​ ​ — ​ ​ 2,993 ​ ​ — ​ ​ — ​ ​ 2,993 Total $ 631 ​ $ 4,781 ​ $ (2,279) ​ $ 5 ​ $ 3,138 ​

Subsequent events

Subsequent events	9 Months Ended
	Sep. 30, 2020
Subsequent events
Subsequent events	20. Subsequent events The Company reviews all activity subsequent to the end of the quarter but prior to issuance of the condensed consolidated financial statements for events that could require disclosure or that could impact the carrying value of assets or liabilities as of the balance sheet date. The Company is not aware of any material subsequent events other than the following: 2018 Notes Exchange 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 is expected to close on November 13, 2020 (the Closing Date), subject to customary closing conditions. The 2020 Notes will be governed pursuant to a indenture by and between the Company and Wilmington Trust, National Association, as trustee and collateral agent (the Trustee), dated as of October 17, 2018 (the Base Indenture), as supplemented by the second supplemental indenture thereto to be dated the Closing Date (the Supplement 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 will issue the 2020 Notes in reliance on the exemption from registration provided by Section 3(a)(9) of the Securities Act of 1934, as amended (the Securities Act). Any shares of common stock issued upon conversion of the 2020 Notes will be issued pursuant to Section 3(a)(9) of the Securities Act as an exchange with existing security holders. Based on the initial maximum conversion rate of million shares of common stock are initially issuable upon conversion of the 2020 Notes. The offer and sale of the 2020 Notes and the shares of common stock issuable upon conversion of the 2020 Notes have not been, and will not be, registered under the Securities Act. The foregoing summary of the 2020 Notes, the Base Indenture and the Supplemental Indenture does not purport to be complete and is qualified in its entirety by reference to the text of the 2020 Notes, the Base Indenture and the Supplemental Indenture, and the form of 5.00% Convertible Senior Note due 2048 included in the Supplemental Indenture, which are filed as Exhibits 4.1, 4.2 and 4.3 respectively, with this Quarterly Report on Form 10-Q and are incorporated herein by reference. Repayment of Amended Term Loan ​

Summary of significant accoun_2

Summary of significant accounting policies (Policies)	9 Months Ended
	Sep. 30, 2020
Summary of significant accounting policies
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with generally accepted accounting principles in the United States (GAAP) for interim financial reporting and as required by Regulation S-X, Rule 10-01 under the assumption that the Company will continue as a going concern for the next twelve months. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements, or any adjustments that might result from the uncertainty related to the Company’s ability to continue as a going concern. In the opinion of management, all adjustments (including those which are normal and recurring) considered necessary for a fair presentation of the interim financial information have been included. When preparing financial statements in conformity with GAAP, the Company must make estimates and assumptions that affect the reported amounts and related disclosures at the date of the financial statements. Actual results could differ from those estimates. Additionally, operating results for the three and nine months ended September 30, 2020 are not necessarily indicative of the results that may be expected for any other interim period or for the year ending December 31, 2020. For further information, refer to the financial statements and footnotes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019, as filed with the Securities and Exchange Commission (SEC) on March 11, 2020.
Significant Accounting Policies	Significant Accounting Policies
Revenue Recognition	Revenue Recognition Revenue from Contracts with Customers Product Revenue, Net Product Revenue, Net – to community hospitals or oncology clinics with in-office dispensaries who in turn distribute COPIKTRA to patients. In addition to distribution agreements with customers, the Company also entered into arrangements with (1) certain government agencies and various private organizations (Third-Party Payers), which may provide for chargebacks or discounts with respect to the purchase of COPIKTRA, and (2) Medicare and Medicaid, which may provide for certain rebates with respect to the purchase of COPIKTRA. 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 three and nine months ended September 30, 2020, 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 condensed consolidated statements of operations and comprehensive income (loss) for the three and nine months ended September 30, 2020. 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 condensed consolidated statements of operations and comprehensive income (loss) for the three and nine months ended September 30, 2020. 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 condensed 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 condensed 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 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
Concentrations of credit risk and off-balance sheet risk	Concentrations of credit risk and off-balance sheet risk Cash, cash equivalents, short-term 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 September 30, 2020, the Company’s cash, cash equivalents and short-term investments were deposited at two 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 September 30, 2020 there were two customers that cumulatively made up more than 60% 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 each of the three and nine months ended September 30, 2020, there were three and four customers, respectively who each individually accounted for greater than 10% of the Company’s total product revenue, net and license and collaboration revenue.
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 condensed 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 condensed 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 condensed 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 condensed 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 of 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 of disclosures.

Cash, cash equivalents and re_2

Cash, cash equivalents and restricted cash (Tables)	9 Months Ended
	Sep. 30, 2020
Cash, cash equivalents and restricted cash
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 condensed consolidated balance sheets that sum to the total of the same such amounts shown in the condensed consolidated statements of cash flows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 Cash and cash equivalents ​ $ 170,470 ​ $ 43,514 Restricted cash ​ 35,242 ​ 35,748 Total cash, cash equivalents and restricted cash ​ $ 205,712 ​ $ 79,262 ​

Fair value of financial instr_2

Fair value of financial instruments (Tables)	9 Months Ended
	Sep. 30, 2020
Fair value of financial instruments
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): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 Description Total Level 1 Level 2 Level 3 Financial assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash equivalents ​ $ 131,693 ​ $ 131,693 ​ $ — ​ $ — ​ Total financial assets ​ $ 131,693 ​ $ 131,693 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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, 2020 ​ $ 450 Fair value adjustment ​ ​ 1,313 Derivative liability extinguished upon conversion ​ (1,763) September 30, 2020 ​ $ —

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2020
Investments
Schedule of cash, cash equivalents and investments	Cash, cash equivalents, restricted cash and short-term investments consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ Gross Gross ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair ​ Cost Gains Losses Value Cash, cash equivalents & restricted cash: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and money market accounts ​ $ 205,712 ​ $ — ​ $ — ​ $ 205,712 ​ Total cash, cash equivalents & restricted cash: ​ $ 205,712 ​ $ — ​ $ — ​ $ 205,712 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 ​

Inventory (Tables)

Inventory (Tables)	9 Months Ended
	Sep. 30, 2020
Inventory
Schedule of inventory	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 Raw materials ​ $ — ​ $ 955 ​ Work in process ​ — ​ 2,040 ​ Finished goods ​ — ​ 101 ​ Total inventories ​ $ — ​ $ 3,096 ​

Accrued expenses (Tables)

Accrued expenses (Tables)	9 Months Ended
	Sep. 30, 2020
Accrued expenses
Schedule of accrued expenses	Accrued expenses consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 Compensation and related benefits ​ 8,078 ​ 7,399 ​ Contract research organization costs ​ ​ 6,423 ​ ​ 5,467 ​ Commercialization costs ​ 2,707 ​ 3,028 ​ Interest ​ ​ 874 ​ ​ 897 ​ Consulting fees ​ 3,283 ​ 1,610 ​ Professional fees ​ 882 ​ 573 ​ Other ​ 917 ​ 391 ​ Total accrued expenses ​ $ 23,164 ​ $ 19,365 ​

Product revenue reserves and _2

Product revenue reserves and allowances (Tables)	9 Months Ended
	Sep. 30, 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 nine months ended September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Third-Party ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Trade ​ Payer ​ Government ​ ​ ​ ​ ​ ​ ​ ​ discounts ​ chargebacks, ​ rebates and ​ ​ ​ ​ ​ ​ ​ ​ and ​ discounts ​ other ​ ​ ​ ​ ​ ​ ​ allowances and fees incentives Returns Total Balance at December 31, 2019 ​ $ 111 ​ $ 255 ​ $ 372 ​ $ 76 ​ $ 814 Provision related to sales in the current year ​ 626 ​ 1,846 ​ 673 ​ 377 ​ 3,522 Adjustments related to prior period sales ​ — ​ — ​ — ​ — ​ — Credits and payments made ​ (590) ​ (1,805) ​ (725) ​ (327) ​ (3,447) Ending balance at September 30, 2020 ​ $ 147 ​ $ 296 ​ $ 320 ​ $ 126 ​ $ 889

Lease (Tables)

Lease (Tables)	9 Months Ended
	Sep. 30, 2020
Leases
Summary of elements of lease expenses	The elements of lease expense were as follows (dollar amounts in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 Lease Expense ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease expense ​ ​ $ 221 ​ $ 222 ​ $ 664 ​ $ 666 Total Lease Expense ​ ​ $ 221 ​ $ 222 ​ $ 664 ​ $ 666 Other Information - Operating Leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows paid for amounts included in measurement of lease liabilities ​ ​ $ 252 ​ $ 180 ​ $ 703 ​ $ 512 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 Other Balance Sheet Information - Operating Leases ​ ​ ​ ​ Weighted average remaining lease term (in years) ​ ​ ​ 4.8 Weighted average discount rate ​ ​ ​ 14.6% Maturity Analysis ​ ​ ​ ​ 2020 ​ ​ $ 252 2021 ​ ​ ​ 1,019 2022 ​ ​ ​ 1,039 2023 ​ ​ ​ 1,060 2024 ​ ​ ​ 1,081 Thereafter ​ ​ ​ 546 Total ​ ​ $ 4,997 Less: Present value discount ​ ​ ​ (1,383) Lease Liability ​ ​ $ 3,614

Long-term debt (Tables)

Long-term debt (Tables)	9 Months Ended
	Sep. 30, 2020
Long-term debt
Schedule of future principal payments under the Loan Agreement	The future principal payments under the Amended Term Loan are as follows as of September 30, 2020 (in thousands): ​ ​ ​ ​ ​ 2021 ​ $ 14,234 2022 ​ ​ 20,766 Total principal payments ​ $ 35,000

Stock-based compensation (Table

Stock-based compensation (Tables)	9 Months Ended
	Sep. 30, 2020
Stock-based compensation
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 621,357 ​ $ 1.92 ​ ​ ​ ​ ​ ​ Exercised (824,894) ​ $ 1.86 ​ ​ ​ ​ ​ ​ Forfeited/cancelled (4,142,720) ​ $ 3.97 ​ ​ ​ ​ ​ ​ Outstanding at September 30, 2020 12,912,267 ​ $ 4.04 6.5 ​ $ 11 ​ Vested at September 30, 2020 8,562,159 ​ $ 4.75 5.6 ​ $ 10 ​ Vested and expected to vest at September 30, 2020(1) 12,702,267 ​ $ 4.07 6.5 ​ $ 11 ​ (1) This represents the number of vested options as of September 30, 2020, plus the number of unvested options expected to vest as of September 30, 2020.
Schedule of assumptions used to estimate fair value of each stock option on grant date	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ ​ 2020 ​ 2019 Risk-free interest rate 0.75 % ​ 2.10 % Volatility 94 % ​ 86 % Dividend yield — ​ ​ — ​ Expected term (years) 5.8 ​ ​ 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 ​ 3,825,007 ​ $ 1.56 ​ Vested ​ (595,289) ​ $ 2.25 ​ Forfeited/cancelled ​ ​ (149,259) ​ $ 2.69 ​ Outstanding at September 30, 2020 ​ 3,758,548 ​ $ 1.55 ​
Schedule of assumptions used to estimate fair value of each employee stock purchase plan on grant date	​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, ​ 2020 ​ 2019 Risk-free interest rate 1.04 % ​ 2.26 % Volatility 109 % ​ 88 % Dividend yield — ​ ​ — ​ Expected term (years) 0.5 ​ ​ 0.5 ​

Net income (loss) per share (Ta

Net income (loss) per share (Tables)	9 Months Ended
	Sep. 30, 2020
Net income (loss) per share
Schedule of computation of basic and diluted net income (loss) per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ 2020 2019 2020 2019 Numerator ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) 13,138 (30,139) ​ (47,862) (110,435) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average shares outstanding - basic ​ 169,510 ​ 74,228 ​ 147,766 ​ 73,988 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effect of dilutive securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ Restricted Stock Units ​ 137 ​ - ​ - ​ - ​ Stock Options ​ 86 ​ - ​ - ​ - ​ Employee Stock Purchase Plan ​ 27 ​ - ​ - ​ - ​ Weighted average shares outstanding - diluted ​ 169,760 ​ 74,228 ​ 147,766 ​ 73,988 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) per share - basic ​ 0.08 ​ (0.41) ​ (0.32) ​ (1.49) ​ Net income (loss) per share - diluted ​ 0.08 ​ (0.41) ​ (0.32) ​ (1.49) ​
Schedule of potentially anti-dilutive securities excluded from calculation of diluted net loss per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ 2020 2019 2020 2019 Outstanding stock options 11,613,978 16,493,690 ​ 12,912,267 16,493,690 ​ Outstanding restricted stock units ​ 807,566 ​ 816,959 ​ 3,758,548 ​ 816,959 ​ 2018 Notes ​ 3,950,032 ​ 20,936,548 ​ 3,950,032 ​ 20,936,548 ​ Employee Stock Purchase Plan ​ — ​ 262,852 ​ 105,533 ​ 262,852 ​ Total potentially dilutive securities 16,371,576 38,510,049 ​ 20,726,380 38,510,049 ​

License and collaboration agr_2

License and collaboration agreements (Tables)	9 Months Ended
	Sep. 30, 2020
License and collaboration agreements
Schedule of proforma financial information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ 2020 2019 2020 2019 Net revenue 1,250 ​ 2,500 ​ 1,250 ​ 2,500 Net loss (13,308) ​ (13,394) ​ (52,551) ​ (48,915) ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss per share—basic ​ (0.08) ​ (0.18) ​ (0.36) ​ (0.66) Net loss per share—diluted ​ (0.08) ​ (0.18) ​ (0.36) ​ (0.66)

Restructurings (Tables)

Restructurings (Tables)	9 Months Ended
	Sep. 30, 2020
Restructurings
Schedule of accrued restructuring liabilities	The following table summarizes the accrued liabilities activity recorded in connection with the restructurings for the nine months ended September 30, 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 ​ ​ (1,653) ​ ​ 10 ​ ​ 145 August 2020 Restructuring ​ ​ — ​ ​ 2,993 ​ ​ — ​ ​ — ​ ​ 2,993 Total $ 631 ​ $ 4,781 ​ $ (2,279) ​ $ 5 ​ $ 3,138

Nature of business (Details)

Nature of business (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Nature of business
Cash, cash equivalents, restricted cash and short-term investments	$ 205,700
Restricted Cash and Cash Equivalents	35,242	$ 35,748
Accumulated deficit	$ (572,647)	$ (524,785)

Summary of significant accoun_3

Summary of significant accounting policies - Revenue Recognition and Accounts Receivable, Net (Details)	9 Months Ended
	Sep. 30, 2020
Revenue recognition
Practical expedient, incremental cost of obtaining contract	true
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

Summary of significant accoun_4

Summary of significant accounting policies - Concentration of Credit Risk (Details) - customer	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Trade accounts receivable | Credit Concentration Risk
Concentrations of credit risk and off-balance sheet risk
Off-balance sheet concentrations of credit risk description		As of September 30, 2020, the Company’s cash, cash equivalents and short-term investments were deposited at two 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		2
Number of customer		2
Trade accounts receivable | Credit Concentration Risk | Minimum
Concentrations of credit risk and off-balance sheet risk
Percentage		60.00%
Revenue | Customer Concentration Risk
Concentrations of credit risk and off-balance sheet risk
Number of customer	3	4
Revenue | Customer Concentration Risk | Minimum
Concentrations of credit risk and off-balance sheet risk
Percentage	10.00%	10.00%

Cash, cash equivalents and re_3

Cash, cash equivalents and restricted cash - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Cash, cash equivalents and restricted cash
Cash and cash equivalents	$ 170,470	$ 43,514
Restricted cash	35,242	35,748
Total cash, cash equivalents and restricted cash	$ 205,712	$ 79,262	$ 104,061	$ 130,608

Cash, cash equivalents and re_4

Cash, cash equivalents and restricted cash (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Restricted cash	$ 35,242	$ 35,748
Restricted Cash and Cash Equivalents, Noncurrent	25,875	35,241
Restricted cash	9,367	507
Research and development agreement with the Leukemia and Lymphoma Society | Prepaid Expenses and Other Current Assets
Property, Plant and Equipment [Line Items]
Restricted cash	0	500
Amended Term Loan Agreement
Property, Plant and Equipment [Line Items]
Restricted cash	35,000	35,000
Restricted Cash and Cash Equivalents, Noncurrent	25,600
Restricted cash	9,400
Letter of credit | Office and Laboratory Space in Needham, Massachusetts
Property, Plant and Equipment [Line Items]
Restricted Cash and Cash Equivalents, Noncurrent	$ 200	$ 200

Fair value of financial instr_3

Fair value of financial instruments - Fair value (Details) - Recurring basis - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial assets
Cash equivalents	$ 131,693	$ 77,176
Short-term investments		31,992
Total financial assets	131,693	109,168
Derivative liability		450
Level 1
Financial assets
Cash equivalents	131,693	75,678
Total financial assets	$ 131,693	75,678
Level 2
Financial assets
Cash equivalents		1,498
Short-term investments		31,992
Total financial assets		33,490
Level 3
Financial assets
Derivative liability		$ 450

Fair value of financial instr_4

Fair value of financial instruments (Details)	Sep. 30, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 23, 2019	Nov. 14, 2019	Oct. 17, 2018
Financial liabilities
Debt, carrying value	$ 35,700,000	$ 35,100,000
5.00% Convertible Senior Notes due 2048
Financial liabilities
Interest rate (as a percent)					5.00%
5.00% Convertible Senior Second Lien Notes due 2048
Financial liabilities
Interest rate (as a percent)			5.00%	5.00%
Level 2 | 5.00% Convertible Senior Notes due 2048
Financial liabilities
Debt, carrying value	$ 20,800,000
Interest rate (as a percent)	5.00%
Debt, fair value	$ 10,000,000
Level 3
Financial liabilities
Debt, fair value	$ 37,000,000	$ 37,000,000
Risk-adjusted discount rate | 5.00% Convertible Senior Second Lien Notes due 2048
Financial liabilities
Debt Instrument, Measurement Input		13.08
Cost Of Equity | 5.00% Convertible Senior Second Lien Notes due 2048
Financial liabilities
Debt Instrument, Measurement Input		16.54

Fair value of financial instr_5

Fair value of financial instruments - Reconciliation of derivative liability (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Income [Extensible List]	Other Nonoperating Income (Expenses)
5.00% Convertible Senior Second Lien Notes due 2048
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 450
Fair value adjustment	1,313
Derivative liability extinguished upon conversion	$ 1,763

Investments (Details)

Investments (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020USD ($)item	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)item	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)item
Investments
Cash, cash equivalents & restricted cash	$ 170,470		$ 170,470		$ 43,514
Total cash, cash equivalents, restricted cash, gross unrealized gains					$ 14
Total cash, cash equivalents, restricted cash and investments, Fair Value	205,700		205,700
Realized gains or losses on investments	$ 0	$ 0	$ 0	$ 0
Number of investments in unrealized loss position | item	0		0		2
Number of investments in unrealized loss position for more than 12 months | item	0		0		0
Unrealized loss on fair value	$ 0		$ 0		$ 5,800
Amortized Cost
Investments
Total cash, cash equivalents, restricted cash and investments					111,241
Fair Value
Investments
Total cash, cash equivalents, restricted cash and investments, Fair Value					111,255
Cash and cash equivalents | Amortized Cost
Investments
Cash, cash equivalents & restricted cash	205,712		205,712		79,262
Cash and cash equivalents | Fair Value
Investments
Cash and cash equivalents, Fair value	205,712		205,712		79,262
Cash and money market accounts | Amortized Cost
Investments
Cash, cash equivalents & restricted cash	205,712		205,712		77,764
Cash and money market accounts | Fair Value
Investments
Cash and cash equivalents, Fair value	$ 205,712		$ 205,712		$ 77,764
Corporate bonds, agency bonds and commercial paper
Investments
Original maturity period, cash and cash equivalents					90 days
Corporate bonds, agency bonds and commercial paper | Amortized Cost
Investments
Cash, cash equivalents & restricted cash					$ 1,498
Corporate bonds, agency bonds and commercial paper | Fair Value
Investments
Cash and cash equivalents, Fair value					1,498
Investments
Investments
Gross unrealized gains					14
Investments | Amortized Cost
Investments
Investments					31,979
Investments | Fair Value
Investments
Short-term investments					$ 31,993
Corporate bonds and commercial paper
Investments
Maximum maturity period, investments					1 year
Gross unrealized gains					$ 14
Corporate bonds and commercial paper | Amortized Cost
Investments
Due within 1 year					31,979
Corporate bonds and commercial paper | Fair Value
Investments
Due within 1 year					$ 31,993

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Inventory
Raw materials			$ 955
Work in process			2,040
Finished goods			101
Total inventories			$ 3,096
Cost of sales - sale of COPIKTRA license and related assets	$ 31,187	$ 31,187
Secura | Duvelisib inventory | Copiktra license and related assets
Inventory
Cost of sales - sale of COPIKTRA license and related assets	$ 6,000	$ 6,000

Intangible assets (Details)

Intangible assets (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Nov. 30, 2018	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Intangible assets
Amortization of acquired intangible asset		$ 100	$ 793	$ 1,177
Cost of sales - sale of COPIKTRA license and related assets		31,187	31,187
Acquired and in-license rights
Intangible assets
Milestone payment payable		22,000	22,000
Payments for milestone payment	$ 22,000
Secura | Intangible asset | Copiktra license and related assets
Intangible assets
Cost of sales - sale of COPIKTRA license and related assets		$ 19,200	$ 19,200

Accrued expenses (Details)

Accrued expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accrued expenses
Compensation and related benefits	$ 8,078	$ 7,399
Contract research organization costs	6,423	5,467
Commercialization costs	2,707	3,028
Interest	874	897
Consulting fees	3,283	1,610
Professional fees	882	573
Other	917	391
Total accrued expenses	$ 23,164	$ 19,365

Product revenue reserves and _3

Product revenue reserves and allowances (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	$ 814
Provision related to sales in the current year	3,522
Credits and payments made	(3,447)
Product revenue reserves and allowances at ending	889
Trade discounts and allowances
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	111
Provision related to sales in the current year	626
Credits and payments made	(590)
Product revenue reserves and allowances at ending	147
Third-Party Payer chargebacks, discounts and fees
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	255
Provision related to sales in the current year	1,846
Credits and payments made	(1,805)
Product revenue reserves and allowances at ending	296
Government rebates and other incentives
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	372
Provision related to sales in the current year	673
Credits and payments made	(725)
Product revenue reserves and allowances at ending	320
Returns
Product revenue reserves and allowances
Product revenue reserves and allowances at beginning	76
Provision related to sales in the current year	377
Credits and payments made	(327)
Product revenue reserves and allowances at ending	$ 126

Leases - Leases (Details)

Leases - Leases (Details) - Office and Laboratory Space in Needham, Massachusetts $ in Millions	Feb. 15, 2018USD ($)ft²	Apr. 15, 2014ft²
Leases
Area of space | ft²	27,810	15,197
Minimum
Leases
Operating lease expense	$ 0.7
Maximum
Leases
Operating lease expense	$ 1.1

Leases - Balance sheet and othe

Leases - Balance sheet and other information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Leases
Right-of use asset	$ 2,820		$ 2,820		$ 3,077
Lease Expense
Operating lease expense	221	$ 222	664	$ 666
Total Lease Expense	221	222	664	666
Other Information - Operating Leases
Operating cash flows paid for amounts included in measurement of lease liabilities	$ 252	$ 180	$ 703	$ 512
Weighted average remaining lease term (in years)	4 years 9 months 18 days		4 years 9 months 18 days
Weighted average discount rate	14.60%		14.60%
Maturity Analysis
2020	$ 252		$ 252
2021	1,019		1,019
2022	1,039		1,039
2023	1,060		1,060
2024	1,081		1,081
Thereafter	546		546
Total	4,997		4,997
Less: Present value discount	(1,383)		(1,383)
Lease Liability	$ 3,614		$ 3,614

Long-term debt - Hercules term

Long-term debt - Hercules term loan facility (Details) - USD ($)	Nov. 14, 2019	Apr. 23, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Apr. 22, 2019	Mar. 21, 2017
Long-term debt
Amount drawn				$ 9,694,000
Restricted cash			$ 35,242,000		$ 35,748,000
Amended Term Loan Agreement
Long-term debt
Restricted cash			$ 35,000,000		$ 35,000,000
Amended Term Loan Agreement | Trailing six months prior to December 31, 2020
Long-term debt
Debt Covenant Percentage Related To Outstanding Debt Obligations			50.00%
Debt Covenant Percentage Related To Net Product Revenue Minimum			80.00%
Medium-term Notes [Member] | Original Loan Agreement
Long-term debt
Maximum borrowing capacity							$ 25,000,000
Medium-term Notes [Member] | Amended Term Loan Agreement
Long-term debt
Maximum borrowing capacity	$ 75,000,000	$ 75,000,000
Outstanding amount		35,000,000	$ 35,000,000			$ 25,000,000
Amount drawn		10,000,000
Remaining borrowing capacity		$ 40,000,000
Outstanding accrued interest and the final payment fee (as a percent)		4.50%
Outstanding accrued interest and the final payment fee		$ 1,100,000
Prepayment charges due		$ 0
Future principal payments
2021			14,234,000
2022			20,766,000
Total principal payments			$ 35,000,000
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		$ 37,500,000
Medium-term Notes [Member] | Amended Term Loan Agreement | On or before June 30, 2020
Long-term debt
Net product revenue		50,000,000
Medium-term Notes [Member] | Amended Term Loan Agreement | Trailing six months prior to December 31, 2020
Long-term debt
Net product revenue	$ 20,000,000	40,000,000
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		25,000,000
Medium-term Notes [Member] | Amended Term Loan Agreement | Plan | Maximum
Long-term debt
Amount drawn		$ 15,000,000

Convertible Senior Notes (Detai

Convertible Senior Notes (Details) $ / shares in Units, $ in Thousands	Dec. 23, 2019USD ($)D$ / shares	Nov. 14, 2019USD ($)D$ / shares	Oct. 17, 2018USD ($)$ / shares	Jul. 17, 2018D	Sep. 30, 2020USD ($)$ / shares	Mar. 31, 2020USD ($)shares	Sep. 30, 2020USD ($)$ / shares	Dec. 31, 2019USD ($)$ / shares	Nov. 11, 2019$ / shares	Oct. 11, 2018$ / shares
Convertible Notes
Common stock, par value (in dollars per share) | $ / shares					$ 0.0001		$ 0.0001	$ 0.0001
Change in fair value of conversion feature							$ (1,313)
Other Nonoperating Income (Expenses)							(1,313)
Interest make-whole payments on the 2019 Notes							1,763
Other Nonoperating Income (Expense)
Convertible Notes
Other Nonoperating Income (Expenses)					$ 0		1,300
5.00% Convertible Senior Notes due 2048
Convertible Notes
Aggregate principal amount			$ 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%
Common stock, par value (in dollars per share) | $ / shares			$ 0.0001
Initial conversion rate			0.1395771
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 | D				20
Consecutive trading days | D				30
5.00% Convertible Senior Second Lien Notes due 2048
Convertible Notes
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	0.6060606	0.6060606
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
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	$ 200
Derivative liability	$ 200	$ 200
Fair value of 2019 Interest Make-Whole Provision								$ 500
Debt conversion, Converted Instrument, Cash						$ 1,800
Debt Conversion, Converted Instrument, Shares Issued | shares						34,796,350

Common stock (Details)

Common stock (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 03, 2020	Feb. 27, 2020	Aug. 31, 2017	Mar. 31, 2017	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2020	Sep. 30, 2020
Subsidiary, Sale of Stock [Line Items]
Proceeds from the issuance of common stock, net								$ 106,059
Private Investment in Public Equity (PIPE)
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares)		46,511,628
Share price (in dollars per share)		$ 2.15
Share price premium (as percentage)		12.60%
Share price, prior to premium price (in dollars per share)		$ 1.91
Proceeds from the issuance of common stock, net	$ 93,800
Private Investment in Public Equity (PIPE) | Common stock
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares)							46,511,628
At-the-market equity offering program | Common stock
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares)					0	6,769,559		6,769,559	18,287,913
Maximum value of common stock allowed to be sold			$ 75,000	$ 35,000
Net proceeds from issuance of stock					$ 0			$ 12,200	$ 59,600

Stock-based compensation - Stoc

Stock-based compensation - Stock Options (Details) - Stock options - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Shares
Outstanding at the beginning of the period (in shares)	17,258,524
Granted (in shares)	621,357
Exercised (in shares)	(824,894)
Forfeited/cancelled (in shares)	(4,142,720)
Outstanding at the end of the period (in shares)	12,912,267		17,258,524
Vested at the end of the period (in shares)	8,562,159
Vested and expected to vest at end of period (in shares)	12,702,267
Weighted-average exercise price per share
Outstanding at the beginning of the period (in dollars per share)	$ 4
Granted (in dollars per share)	1.92
Exercised (in dollars per share)	1.86
Forfeited/cancelled (in dollars per share)	3.97
Outstanding at the end of the period (in dollars per share)	4.04		$ 4
Vested at the end of the period (in dollars per share)	4.75
Vested and expected to vest at end of the period (in dollars per share)	$ 4.07
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 7 months 6 days
Vested and expected to vest at the end of the period	6 years 6 months
Aggregate intrinsic value
Outstanding at the beginning of the period (in dollars)	$ 185
Outstanding at the end of the period (in dollars)	11		$ 185
Vested at the end of the period (in dollars)	10
Vested and expected to vest at end of the period (in dollars)	$ 11
Assumptions used to estimate fair value of each stock-based award on the grant date
Risk-free interest rate (as a percent)	0.75%	2.10%
Volatility (as a percent)	94.00%	86.00%
Dividend yield (as a percent)	0.00%	0.00%
Expected term	5 years 9 months 18 days	5 years 9 months 18 days

Stock-based compensation - Rest

Stock-based compensation - Restricted Stock (Details) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020USD ($)$ / sharesshares	Sep. 30, 2020USD ($)item$ / sharesshares
Selling, general and administrative expenses
Stock-based compensation
Stock-based compensation expense | $	$ 0.5	$ 0.5
Restricted stock units
Stock-based compensation
Number of shares holder to receive when RSU vests		1
Shares
Unvested at the beginning of the period (in shares)		678,089
Granted (in shares)		3,825,007
Vested (in shares)		(595,289)
Forfeited (in shares)		(149,259)
Unvested at the end of the period (in shares)	3,758,548	3,758,548
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		1.56
Vested (in dollars per share) | $ / shares		2.25
Forfeited/cancelled (in dollars per share) | $ / shares		2.69
Unvested at the end of the period (in dollars per share) | $ / shares	$ 1.55	$ 1.55
Restricted stock units | Four Annual Payments
Stock-based compensation
Number of installments | item		4
Number of anniversaries | item		4
Vesting percentage		50.00%
Vesting period		4 months
Restricted stock units | First Anniversary Payment
Stock-based compensation
Vesting percentage		100.00%
Vesting period		1 year
Restricted stock units | First Anniversary Payment and Each Successive Quarter Thereafter
Stock-based compensation
Award vesting rights, first anniversary, percentage		33.33%
Award vesting rights, successive quarters after anniversary, percentage		8.33%
Restricted stock units | Vesting approximately 21 months from the commencement date
Stock-based compensation
Vesting percentage		100.00%
Vesting period		21 months
Restricted stock units | After one year from vesting commencement
Stock-based compensation
Vesting percentage		50.00%

Stock-based compensation - Empl

Stock-based compensation - Employee Stock Purchase Plan (Details) $ in Thousands	Dec. 18, 2018itemshares	Sep. 30, 2020USD ($)shares	Sep. 30, 2019USD ($)
Assumptions used to estimate fair value of each stock-based award on the grant date
Proceeds from the issuance of common stock, net		$ 106,059
2018 ESPP
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
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%
Dividend yield (as a percent)		0.00%	0.00%
Expected term		6 months	6 months
Stock-based compensation expense		$ 100	$ 400
Issuance of common stock under ESPP | shares		358,193
Proceeds from the issuance of common stock, net		$ 400

Net income (loss) per share - b

Net income (loss) per share - basic and diluted net income (loss) per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Computation of basic and diluted net income (loss) per share:
Net income (loss)	$ 13,138	$ (23,010)	$ (37,990)	$ (30,139)	$ (42,194)	$ (38,102)	$ (47,862)	$ (110,435)
Weighted average shares outstanding - basic	169,510			74,228			147,766	73,988
Effect of dilutive securities:	169,760			74,228			147,766	73,988
Weighted average diluted shares outstanding	169,760			74,228			147,766	73,988
Net income (loss) per share - basic	$ 0.08			$ (0.41)			$ (0.32)	$ (1.49)
Net income (loss) per share - diluted	$ 0.08			$ (0.41)			$ (0.32)	$ (1.49)
Restricted stock units
Computation of basic and diluted net income (loss) per share:
Effect of dilutive securities:	137
Stock options
Computation of basic and diluted net income (loss) per share:
Effect of dilutive securities:	86
Employee Stock Purchase Plan
Computation of basic and diluted net income (loss) per share:
Effect of dilutive securities:	27

Net income (loss) per share (De

Net income (loss) per share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	16,371,576	38,510,049	20,726,380	38,510,049
Stock options
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	11,613,978	16,493,690	12,912,267	16,493,690
Restricted stock units
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	807,566	816,959	3,758,548	816,959
2018 Notes
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	3,950,032	20,936,548	3,950,032	20,936,548
Employee Stock Purchase Plan
Net loss per share
Potentially anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	0	262,852	105,533	262,852

License and collaboration agr_3

License and collaboration agreements - Secura Bio Inc (Details) - USD ($) $ / shares in Units, $ in Thousands	Jul. 25, 2019	Sep. 30, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized			$ 78,647			$ 9,032			$ 88,010	$ 13,840
Cost of sales - sale of COPIKTRA license and related assets			31,187						31,187
Earnings Per Share, Pro Forma [Abstract]
Net income (loss)			13,138	$ (23,010)	$ (37,990)	(30,139)	$ (42,194)	$ (38,102)	(47,862)	(110,435)
Copiktra license and related assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized			70,000						70,000
Secura | Intangible asset | Copiktra license and related assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cost of sales - sale of COPIKTRA license and related assets			19,200						19,200
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						6,000
License and Collaboration Agreement | Sanofi
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment						5,000				5,000
Earnings Per Share, Pro Forma [Abstract]
Net product revenue			2,500						2,500
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						35,000
Milestone payments receivable upon approval for commercial sale		10,000	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%
Number of days written prior notice required for other party to terminate agreement									5 days
Cost of sales - sale of COPIKTRA license and related assets									$ 31,200
Earnings Per Share, Pro Forma [Abstract]
Net product revenue			1,250			2,500			1,250	2,500
Net income (loss)			$ (13,308)			$ (13,394)			$ (52,551)	$ (48,915)
Net loss per share-basic			$ (0.08)			$ (0.18)			$ (0.36)	$ (0.66)
Net loss per share-diluted			$ (0.08)			$ (0.18)			$ (0.36)	$ (0.66)
Nonrecurring pro forma transaction costs			$ 3,500						$ 3,500
License and Collaboration Agreement | Secura | Copiktra license and related assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized			70,000						70,000
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						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						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						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						45,000
Sales milestone receivable		$ 50,000	50,000						50,000
Term of agreement		1 year
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						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						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						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						$ 5,800
License and Collaboration Agreement | Secura | Duvelisib | Sale
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment		$ 70,000
License and Collaboration Agreement | Sanofi
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Maximum aggregate payments entitled to receive if all milestones successfully achieved	$ 42,000
Earnings Per Share, Pro Forma [Abstract]
Revenue recognition percent milestone earned			50.00%			50.00%			50.00%	50.00%

License and collaboration agr_4

License and collaboration agreements - Chugai Pharmaceutical Co., Ltd (Chugai) (Details) - Chugai Pharmaceutical Co., Ltd. - License and Collaboration Agreement - USD ($) $ in Millions	Jan. 07, 2020	Feb. 29, 2020	Sep. 30, 2020
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
Research and development expense.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
One-time cash payment			$ 3

License and collaboration agr_5

License and collaboration agreements - Sanofi (Details) - License and Collaboration Agreement - Sanofi $ in Millions	Oct. 01, 2020	Jul. 25, 2019USD ($)	Aug. 31, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2020Milestone
License and collaboration agreements
Proceeds received			$ 5
Maximum aggregate payments entitled to receive if all milestones successfully achieved		$ 42
Number of additional milestones achieved | Milestone					2
License revenue				$ 2.5
Percentage of future milestone payments and royalties entitled	50.00%

License and collaboration agr_6

License and collaboration agreements - Yakult (Details) - License and Collaboration Agreement - Yakult $ in Millions	Oct. 01, 2020	Jun. 05, 2018USD ($)	Jun. 30, 2018USD ($)	Sep. 30, 2020Milestone
License and collaboration agreements
Proceeds received			$ 10
Maximum aggregate payments entitled to receive if all milestones successfully achieved		$ 90
Number of additional milestones achieved | Milestone				0
Percentage of future milestone payments and royalties entitled	50.00%

License and collaboration agr_7

License and collaboration agreements - CSPC (Details) - License and Collaboration Agreement - CSPC $ in Millions	Oct. 01, 2020	Sep. 25, 2018USD ($)	Sep. 30, 2020Milestone	Dec. 31, 2018USD ($)
License and collaboration agreements
Proceeds received				$ 15
Maximum aggregate payments entitled to receive if all milestones successfully achieved		$ 160
Number of additional milestones achieved | Milestone			0
Percentage of future milestone payments and royalties entitled	50.00%

Restructurings (Details)

Restructurings (Details) $ in Millions	Feb. 27, 2020position	Oct. 28, 2019position	Aug. 31, 2020position	Sep. 30, 2020USD ($)	Dec. 31, 2019USD ($)	Sep. 30, 2020USD ($)
Restructuring Costs
Restructuring costs				$ 3		$ 4.8
Selling, general and administrative expenses
Restructuring Costs
Restructuring costs				2.9		4.3
Research and development expense.
Restructuring Costs
Restructuring costs				$ 0.1		$ 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	9 Months Ended
	Sep. 30, 2020USD ($)
Restructuring Cost and Reserve [Line Items]
Amounts accrued at, December 31, 2019	$ 631
Charges	4,781
Amount Paid	(2,279)
Adjustments	5
Amounts accrued at, September 30, 2020	3,138
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, September 30, 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	(1,653)
Adjustments	10
Amounts accrued at, September 30, 2020	145
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	0
Adjustments	0
Amounts accrued at, September 30, 2020	$ 2,993

Subsequent events (Details)

Subsequent events (Details) $ / shares in Units, shares in Millions, $ in Millions	Nov. 09, 2020USD ($)	Nov. 06, 2020USD ($)D$ / sharesshares	Dec. 23, 2019USD ($)	Nov. 14, 2019USD ($)	Oct. 17, 2018USD ($)$ / shares	Jul. 17, 2018D	Nov. 05, 2020USD ($)	Oct. 11, 2018$ / shares
5.00% Convertible Senior Notes due 2048
Subsequent events
Conversion of Notes into common stock			$ 7.4	$ 114.3
Aggregate principal amount					$ 150
Interest rate (as a percent)					5.00%
Percentage of stock price trigger for conversion						130.00%
Trading days | D						20
Consecutive trading days | D						30
Conversion rate of the notes to common stock, per $1,000 principal amount of notes					0.1395771
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
Subsequent event | 5.00% Convertible Senior Notes due 2048
Subsequent events
Aggregate principal amount		$ 28					$ 28
Interest rate (as a percent)		5.00%
Percentage of stock price trigger for conversion		123.08%
Trading days | D		20
Consecutive trading days | D		30
Conversion rate of the notes to common stock, per $1,000 principal amount of notes		0.3076923
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 principal amount of notes		100.00%
Subsequent event | 5.00% Convertible Senior Notes due 2048 | Maximum
Subsequent events
Conversion rate of the notes to common stock, per $1,000 principal amount of notes		0.8333333
Shares issued on conversion | shares		23.3
Subsequent event | Amended Term Loan Agreement
Subsequent events
Repayment of term loan	$ 37.4
Repayment of principal	35
Repayment of final payment	1.8
Prepayment penalty fee	0.5
Accrued and unpaid interest	$ 0.1