Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net loss	$ (62,421)	$ (69,580)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	417	513
Amortization of intangibles	9,011	9,011
Amortization of premium/discount on investments	0	(11)
Non-cash interest expense related to sale of future royalties	2,345	2,162
Non-cash royalty revenue related to sale of future royalties	(329)	(20)
Non-cash interest expense	246	229
Non-cash operating lease expense	(557)	(494)
Fair value step-up of inventory sold or written off	0	21,575
Write-down of inventory	5,344	5,075
Change in excess inventory purchase commitments	(773)	(8,945)
Stock-based compensation	4,536	5,992
Change in fair value of derivative liability	(710)	80
Changes in operating assets and liabilities:
Accounts receivable	(13,707)	(8,380)
Inventory	(5,247)	(19,193)
Prepaid expenses and other current assets	9,019	2,268
Other long-term assets	3,297	1,361
Accounts payable	(7,358)	(4,912)
Accrued expense	4,426	(4,877)
Operating lease liabilities	616	407
Deferred revenue	33,416	(3,007)
Other non-current liabilities	(3,191)	0
Net cash used in operating activities	(21,620)	(70,746)
Investing activities:
Purchase of equipment	(114)	(59)
Proceeds from the maturities of available for sale securities	0	20,000
Net cash (used in) provided by investing activities	(114)	19,941
Financing activities:
Proceeds from sale of future royalties, net	0	44,783
Proceeds from refund liabilities to customers	40,000	0
Proceeds from the issuance of common stock, net of issuance costs	7,178	29,327
Proceeds from the sale of stock under employee stock purchase plan	367	367
Proceeds from the exercise of stock options	0	0
Net cash provided by financing activities	47,545	74,477
Increase in cash, cash equivalents, and restricted cash	25,811	23,672
Cash, cash equivalents, and restricted cash at beginning of the period	151,839	231,132
Cash, cash equivalents, and restricted cash at end of the period	177,650	254,804
Non-cash financing activities
Unpaid offering costs	$ 0	$ 171