CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Operating activities
Net loss	$ (131,500)	$ (132,725)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation expense	12,034	11,401
Depreciation and amortization	3,826	4,478
Amortization of debt issuance costs	1,119	1,260
Allowance for excess inventory	9,712
Other	751	1,908
Changes in operating assets and liabilities:
Accounts receivable	7,332	2,331
Inventory	9,263	6,525
Prepaid and accrued research and development expenses	(9,453)	(1,736)
Other operating assets and liabilities	115	(3,963)
Accounts payable	(2,518)	(4,551)
Other accrued expenses	5,697	6,427
Net cash used in operating activities	(93,622)	(108,645)
Investing activities
Purchases of property and equipment	(108)	(154)
Net cash used in investing activities	(108)	(154)
Financing activities
Proceeds from sale of common stock, net of issuance costs	28,628	72,472
Proceeds from borrowings under financing agreement	17,981	27,154
Proceeds from the exercise of stock options and employee stock purchases	392	683
Payments on finance leases		(780)
Payments on other long-term liabilities		(213)
Net cash provided by financing activities	47,001	99,316
Effect of exchange rate changes on cash and cash equivalents	(2,120)	(542)
Decrease in cash and cash equivalents	(48,849)	(10,025)
Cash and cash equivalents at beginning of period	143,428	240,229
Cash and cash equivalents at end of period	94,579	230,204
Supplemental disclosure of cash flow information:
Cash paid for interest	5,099	5,167
Non-cash investing and financing activities:
Vesting of restricted stock units	$ 2,225	$ 8,274