Consolidated Balance Sheets - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 190,459	$ 85,918
Short-term investments	38,156	163,322
Accounts receivable	22,497	12,881
Inventory	4,106	2,644
Prepaid expenses and other current assets	14,039	9,285
Restricted cash	6,349	2,481
Total current assets	275,606	276,531
Property and equipment, net	1,642	2,219
Operating lease right-of-use assets	7,915	9,363
Long-term investments		24,215
Other assets	19,505
Other assets	19,505
Restricted cash	637	722
Total assets	305,305	313,050
Current liabilities:
Accounts payable	1,603	4,450
Accrued expenses	69,121	52,930
Deferred revenue		297
Operating lease liabilities	2,316	1,917
Other current liabilities	678	609
Total current liabilities	73,718	60,203
Convertible senior notes	169,293	117,928
Deferred royalty obligation	132,998	73,088
Operating lease liabilities, net of current portion	8,969	11,285
Total liabilities	384,978	262,504
Stockholders' (deficit) equity:
Preferred stock, $0.0001 par value; 5,000 shares authorized; none issued and outstanding
Common stock, $0.0001 par value; 200,000 shares authorized; 75,746 and 73,923 shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively	8	7
Additional paid-in capital	1,098,776	1,119,632
Accumulated other comprehensive income	191	518
Accumulated deficit	(1,178,648)	(1,069,611)
Total stockholders' (deficit) equity	(79,673)	50,546
Total liabilities and stockholders' (deficit) equity	$ 305,305	$ 313,050