Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Current assets
Cash and cash equivalents	$ 57,857	$ 71,084
Restricted cash	110	110
Prepaid materials	3,475	2,098
Prepaid expenses and other current assets	1,075	1,165
Total current assets	62,517	74,457
Other assets	1,998	1,987
Total Assets	64,515	76,444
Current liabilities
Accounts payable	2,010	679
Accrued expenses	2,200	919
Payroll liabilities	1,054	1,862
Other current liabilities	1,556	1,507
Total current liabilities	6,820	4,967
Total Liabilities	6,820	4,967
Commitments and contingencies (Note 12)
Stockholders' equity
Convertible preferred stock - $0.001 par value; 10,000,000 shares authorized; 577 and 582 shares issued and outstanding as of June 30, 2025 and December 31, 2024	0	0
Common stock - $0.18 par value; 350,000,000 shares authorized; 129,171,424 and 129,170,004 shares issued and outstanding as of June 30, 2025 and December 31, 2024	23,488	23,488
Additional paid-in capital	262,615	261,256
Treasury stock, at cost; 1,320,046 shares of common stock at June 30, 2025 and December 31, 2024	(1,475)	(1,475)
Accumulated deficit	(226,933)	(211,792)
Total Stockholders' Equity	57,695	71,477
Total Liabilities and Stockholders' Equity	$ 64,515	$ 76,444