Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Current assets
Cash and cash equivalents	$ 65,116	$ 71,084
Restricted cash	110	110
Prepaid materials	2,079	2,098
Prepaid expenses and other current assets	1,439	1,165
Total current assets	68,744	74,457
Other assets	2,003	1,987
Total Assets	70,747	76,444
Current liabilities
Accounts payable	1,165	679
Accrued expenses	1,788	919
Payroll liabilities	942	1,862
Other current liabilities	1,530	1,507
Total current liabilities	5,425	4,967
Total Liabilities	5,425	4,967
Commitments and contingencies (Note 12)
Stockholders' equity
Convertible preferred stock - $0.001 par value; 10,000,000 shares authorized; 582 shares issued and outstanding as of March 31, 2025 and December 31, 2024	0	0
Common stock - $0.18 par value; 350,000,000 shares authorized; 129,170,004 shares issued and outstanding as of March 31, 2025 and December 31, 2024	23,488	23,488
Additional paid-in capital	261,819	261,256
Treasury stock, at cost; 1,320,046 shares of common stock at March 31, 2025 and December 31, 2024	(1,475)	(1,475)
Accumulated deficit	(218,510)	(211,792)
Total Stockholders' Equity	65,322	71,477
Total Liabilities and Stockholders' Equity	$ 70,747	$ 76,444