Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 88,460	$ 110,890
Restricted cash	110	110
Prepaid materials	1,487	5,247
Prepaid expenses and other current assets	2,162	1,207
Research and development tax rebate receivable	0	743
Total current assets	92,219	118,197
Investment in equity securities	1,710	4,700
Other assets	2,323	635
Total Assets	96,252	123,532
Current liabilities
Accounts payable	806	2,965
Accrued expenses	973	1,059
Payroll liabilities	1,654	1,525
Other current liabilities	1,803	19
Total current liabilities	5,236	5,568
Total Liabilities	5,236	5,568
Commitments and contingencies (Note 13)
Stockholders' equity
Convertible preferred stock - $0.001 par value; 10,000,000 shares authorized; 582 shares issued and outstanding as of December 31, 2023 and 2022	0	0
Common stock - $0.18 par value; 175,000,000 shares authorized; 125,304,064 and 126,624,110 shares issued and outstanding as of December 31, 2023 and 2022, respectively	22,792	22,792
Additional paid-in capital	255,987	251,366
Treasury stock, at cost; 1,320,046 and 0 shares of common stock at December 31, 2023 and 2022, respectively	(1,475)	0
Accumulated deficit	(186,288)	(156,194)
Total Stockholders' Equity	91,016	117,964
Total Liabilities and Stockholders' Equity	$ 96,252	$ 123,532