CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net loss	$ (20,976)	$ (12,280)
Adjustments to reconcile net loss to cash flows used in operating activities:
Amortization of intangible assets	615	615
Depreciation of property and equipment	81	72
Amortization of debt discount and premium and discount on available-for-sale marketable securities	110	147
Loss on extinguishment of debt	1,559	0
Stock-based compensation	3,477	988
Changes in operating assets and liabilities:
Accounts receivable and other current assets	(2,937)	(2,317)
Inventory	280	(248)
Accounts payable and accrued expenses	(2,107)	(1,798)
Right-of-use assets and operating lease liabilities	(35)	(38)
Deferred revenue	(225)	(240)
Net cash used in operating activities	(20,158)	(15,099)
Cash flows from investing activities:
Purchases of marketable securities	(62,293)	0
Sales and maturities of marketable securities	6,000	0
Purchases of property and equipment	(149)	0
Net cash used in investing activities	(56,442)	0
Cash flows from financing activities:
Proceeds from issuance of stock	0	115,667
Proceeds from issuance of long-term debt	30,000	0
Payment of equity and debt issue costs	(352)	(6,935)
Payment of long-term debt	(38,235)	0
Payment of extinguishment of debt costs	(2,294)	0
Borrowings under revolving facility	11,459	0
Repayment under revolving facility	(984)	0
Net settlement of stock units to satisfy statutory tax withholding	(250)	(128)
Proceeds from exercise of stock options	241	183
Principal payments on finance lease obligations	(33)	(18)
Net cash (used in) provided by financing activities	(448)	108,769
Net increase (decrease) in cash, cash equivalents and restricted cash	(77,048)	93,670
Cash, cash equivalents and restricted cash at beginning of period	178,743	45,059
Cash, cash equivalents and restricted cash at end of period	101,695	138,729
Supplemental cash flow information:
Cash interest paid	941	1,195
Supplemental disclosure of non-cash investing and financing activities:
Stock issuance costs	0	329
Debt issue costs	244	0
Accrued term loan exit fee	600	0
Principal portion of finance lease liabilities	$ 0	$ 12