Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
CURRENT ASSETS:
Cash and cash equivalents	$ 5,851	$ 16,932
Marketable securities	16,584	19,591
Accounts receivable, net	76	131
Inventories, net	258	583
Prepaid and other current assets	1,482	2,517
Total current assets	24,251	39,754
Right-of-use assets	703	11,226
Property and equipment, net	630	281
Restricted cash	0	2,150
Other noncurrent assets	784	906
Total assets	26,368	54,317
CURRENT LIABILITIES:
Accounts payable	3,717	3,442
Accrued expenses and other current liabilities	6,960	6,585
Contract liabilities	35	0
Total current liabilities	10,712	10,027
Operating lease liabilities, noncurrent	537	14,858
Convertible note	146	0
Other noncurrent liabilities	67	409
Total liabilities	11,462	25,294
COMMITMENTS AND CONTINGENCIES (Note 17)
STOCKHOLDERS’ EQUITY:
Preferred stock—$0.0001 par value: 1,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock—$0.0001 par value: 600,000,000 shares authorized; 8,940,942 and 6,310,090 shares issued and outstanding at September 30, 2024 and December 31, 2023	1	1
Additional paid-in capital	379,425	366,647
Accumulated other comprehensive income	27	10
Accumulated deficit	(364,547)	(337,635)
Total stockholders’ equity	14,906	29,023
Total liabilities and stockholders’ equity	$ 26,368	$ 54,317