CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
OPERATING CASH FLOW ACTIVITIES:
Net loss	$ (179,053)	$ (165,757)
Reconciliation of net loss to net cash used in operating activities
Depreciation	318	327
Accretion of debt discount and amortization of financing costs	1,373	860
Change in fair value of derivative liabilities	(438)	389
Stock-based compensation expense	18,614	17,337
Payable-in-kind interest on Credit Agreement	1,872	807
Loss on disposal of equipment	2	22
Operating lease right-of-use assets	288	271
Changes in operating assets and liabilities
Accounts receivable	177	(248)
Inventory	(6)	(1,985)
Prepaid expenses, other current assets and other assets	2,888	(3,905)
Accounts payable, accrued expenses, due to related parties, and other current liabilities	(3,219)	13,030
Accrued interest	2,497	3,804
Operating lease liabilities	(319)	(293)
Net cash used in operating activities	(155,006)	(135,341)
INVESTING CASH FLOW ACTIVITIES:
Purchases of equipment and leasehold improvements	(20)	(139)
Net cash used in investing activities	(20)	(139)
FINANCING CASH FLOW ACTIVITIES:
Proceeds from long-term debt		98,600
Debt issuance costs	(180)	(2,646)
Proceeds from issuance of common stock	27,032
Offering costs for common stock issuance	(811)
Payment of employee tax obligations related to vesting restricted stock units	(27)
Exercise of stock options	508	283
Net cash provided by financing activities	26,522	96,237
Net decrease in cash and cash equivalents	(128,504)	(39,243)
Cash and cash equivalents, beginning of the period	193,725	232,968
Cash and cash equivalents, end of the period	65,221	193,725
Supplemental cash flow information:
Issuance of stock purchase warrants	200	3,245
Repricing of stock purchase warrants	254
Interest paid	7,551	$ 2,697
Conversion of accrued interest to long-term debt	$ 767