STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities:
Net loss	$ (4,679,000)	$ (35,140,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	2,000	2,315,000
Property and equipment right-of-use asset impairment	0	4,803,000
Amortization of financing costs	0	1,339,000
Stock-based compensation	435,000	2,800,000
Decrease in the carrying amount of right-of-use assets	0	286,000
Gain on lease modification and termination	0	(298,000)
Loss on sale of equipment, net	0	7,000
Change in operating assets and liabilities:
Receivables	(4,000)	3,000
Prepaid expenses and other current assets	539,000	(1,399,000)
Deposits	0	42,000
Other non-current liability	0	500,000
Accounts payable	(100,000)	(773,000)
Accrued expenses	(1,164,000)	(3,989,000)
Lease liabilities	0	(610,000)
Other liabilities, non-current	0	(28,000)
Net cash used in operating activities	(4,971,000)	(30,142,000)
Cash flows from investing activities:
Purchases of property and equipment	0	(197,000)
Proceeds from the disposal of property and equipment	0	1,543,000
Net cash provided by investing activities	0	1,346,000
Cash flows from financing activities:
Proceeds from the issuance of common stock	0	92,000
Repayment of long-term debt	0	(18,105,000)
Debt extinguishment	0	(125,000)
Net cash used in financing activities	0	(18,138,000)
Net decrease in cash, cash equivalents and restricted cash	(4,971,000)	(46,934,000)
Cash, cash equivalents and restricted cash, beginning of period	6,062,000	52,996,000
Cash and cash equivalents, end of period	1,091,000	6,062,000
Supplementary disclosure of cash flow information:
Cash paid for interest	0	2,063,000
Reduction in right-of-use assets for modification and termination	$ 0	$ 1,839,000