Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Net loss	$ (5,014)	$ (7,607)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	2	2
Non-cash operating lease expense	62	56
Recurring fair value measurements of liabilities	(9)	5
Issuance of common stock to vendors	0	73
Write-off of deferred equity issuance costs	75	0
Loss on disposal of property and equipment	0	4
Stock-based compensation and related charges	138	480
Changes in operating assets and liabilities:
Prepaid and other current assets and other noncurrent assets	(18)	349
Accounts payable and accrued liabilities	1,210	506
Accrued compensation and benefits	(530)	(490)
Operating lease liabilities	(66)	(57)
Net cash used in operating activities	(4,150)	(6,679)
Cash flows from financing activities
Payments on insurance financing debt	(80)	(158)
Proceeds from issuance of common stock and warrants	0	4,000
Proceeds from the exercise of warrants	1	2,503
Payment of warrant inducement issuance costs	0	(343)
Payment of equity issuance costs	(178)	(388)
Proceeds from issuance of common stock under Employee Stock Purchase Plan	3	11
Shares withheld for payment of employee withholding tax liability	0	(25)
Net cash (used in) provided by financing activities	(254)	5,600
Net decrease in cash, cash equivalents and restricted cash	(4,404)	(1,079)
Cash, cash equivalents and restricted cash, beginning of period	9,847	12,458
Cash, cash equivalents and restricted cash, end of period	5,443	11,379
Reconciliation of cash, cash equivalents and restricted cash to the balance sheets:
Cash and cash equivalents	5,417	11,353
Restricted cash	26	26
Total cash, cash equivalents and restricted cash	5,443	11,379
Supplemental disclosures of cash flow information:
Interest paid	1	2
Supplemental disclosures of non-cash investing and financing activities:
Warrant inducement and equity issuance costs included in accounts payable and accrued liabilities	0	68
Transaction costs included in accounts payable and accrued liabilities	0	0
Fair value of warrants issued to solicitation agent	0	94
Fair value of warrants issued to placement agent	0	249
Deferred equity issuance costs recognized as a reduction in additional paid-in capital from financing activities	0	37
Insurance financing debt included in prepaid and other current assets and other noncurrent assets	312	346
Incremental fair value of modified warrants (Note 5)	$ 0	$ 1,975