Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net loss	$ (51,537)	$ (18,709)
Adjustments to reconcile net loss to net cash used in operating activities:
Noncash inventory reserve	1,415
Depreciation	1,546	8
Amortization	102	82
Noncash stock-based compensation	2,472	1,460
Noncash interest	1,262	447
Changes in operating assets and liabilities:
Accounts receivable	(444)
Inventory	(4,875)
Prepaid expenses and other assets	(885)	(686)
Accounts payable and accrued expenses	2,462	2,839
Lease liability	(102)	(90)
Net cash used in operating activities	(48,584)	(14,649)
Cash flows from investing activities:
Purchases of marketable securities		(47,822)
Sales and maturities of marketable securities	39,729
Acquisition of property and equipment	(214)	(222)
Net cash provided by (used in) investing activities	39,515	(48,044)
Cash flows from financing activities:
Proceeds from issuance of long-term debt		20,000
Debt financing costs paid		(1,059)
Proceeds from exercise of stock options	75	285
Net cash provided by financing activities	9,341	67,660
Net increase in cash and cash equivalents	272	4,967
Cash and cash equivalents, beginning of period	14,463	34,479
Cash and cash equivalents, end of period	14,735	39,446
Supplemental disclosure of noncash financing activities
Warrants issued in connection with long-term debt	1,080	3,570
Supplemental cash flow information
Interest paid	1,782	1,498
Public offering
Cash flows from financing activities:
Proceeds from issuance of common stock, net of offering costs		$ 48,434
At-the-market sales
Cash flows from financing activities:
Proceeds from issuance of common stock, net of offering costs	$ 9,266