Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities:
Net loss	$ (21,763)	$ (29,769)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	126	127
Stock-based compensation	1,726	1,984
License rights expense settled in stock	0	772
Change in fair value of warrant liability	(6,125)	1,044
Loss on issuance of warrant liabilities	847	0
Operating lease, net	103	119
Transaction costs allocated to warrant liabilities	993	510
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	1,807	(272)
Accounts payable	(468)	403
Accrued expenses and other current liabilities	(1,108)	1,491
Net cash used in operating activities	(23,862)	(23,591)
Cash flows from investing activities:
Purchase of fixed assets	(13)	(124)
Net cash used in investing activities	(13)	(124)
Cash flows from financing activities:
Proceeds from exercise of warrants	1	0
Payment of tax liability for vested restricted stock units	(26)	(25)
Proceeds from sale of common stock, pre-funded and common warrants, net of issuance and transaction costs	4,660	4,166
Net cash provided by financing activities	4,635	4,141
Effect of exchange rate changes on cash and cash equivalents	(32)	(21)
Net change in cash and cash equivalents	(19,272)	(19,595)
Cash and cash equivalents, at beginning of year	23,550	43,145
Cash and cash equivalents, at end of year	4,278	23,550
Non-cash investing and financing activities:
Transaction costs related to the sale of common stock, pre-funded and common warrants	156	0
Purchases of property and equipment in accounts payable and accrued liabilities	0	26
Offering costs included in accounts payable and accrued liabilities	0	115
Issuance of common stock to acquire license rights	$ 0	$ 772