Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (14,465)	$ (25,412)	$ (71,067)
Adjustments to reconcile net loss to net cash used in operating activities:
Noncash inventory reserve	801	397	5,323
Depreciation	102	1,280	2,064
Amortization	284	254	159
Loss on disposition of assets		11,122
Noncash stock-based compensation	1,981	2,493	3,338
Noncash amortization of deferred financing costs	1,063	1,969	1,661
Unrealized gain on warrants	(6,760)	(25,520)	(3,827)
Changes in operating assets and liabilities:
Accounts receivable	(15)	(1,844)	(668)
Inventory	(2,207)	(763)	(6,289)
Prepaid expenses and other assets	2,270	880	(967)
Accounts payable and accrued expenses	7,688	(628)	5,202
Lease liability	(319)	(175)	(131)
Net cash used in operating activities	(9,577)	(35,947)	(65,202)
Cash flows from investing activities:
Sales and maturities of marketable securities			39,729
Acquisition of property and equipment		(133)	(269)
Net cash (used in) provided by investing activities		(133)	39,460
Cash flows from financing activities:
Proceeds from issuance of common stock in public offering, net of offering costs	6,510	21,936	21,081
Repayments of long-term debt	(975)	(17,375)
Proceeds from exercise of stock options			75
Repayments of note payable	(372)
Net cash provided by financing activities	6,888	22,183	30,422
Net (decrease) increase in cash and cash equivalents	(2,689)	(13,897)	4,680
Cash and cash equivalents, beginning of period	5,246	19,143	14,463
Cash and cash equivalents, end of period	2,557	5,246	19,143
Supplemental disclosure of noncash financing activities
Warrants issued in connection with long-term debt			1,080
Operating right-of-use assets obtained in exchange for new operating lease liabilities			969
Supplemental cash flow information
Interest paid	356	1,162	2,383
Public offering
Cash flows from financing activities:
Proceeds from issuance of preferred stock in registered direct offering, net of offering costs		4,128
At-the-market sales
Cash flows from financing activities:
Proceeds from At-the-Market sales of common stock, net of offering costs	$ 1,725	$ 13,494	$ 9,266