Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 23,767	$ 24,228
Short-term investments	0	14,932
Restricted cash	62	62
Prepaid materials, net	3,010	3,010
Prepaid expenses and other current assets	1,340	1,847
Total current assets	28,179	44,079
Property and equipment, net	1,061	536
Intangibles, net	33	62
Right of use asset	1,477	2,039
Total assets	30,750	46,716
Current liabilities:
Accounts payable	204	175
Accrued liabilities	691	961
Accrued research and development expenses	921	1,252
Accrued compensation	2,979	2,205
Current portion of term loan, less debt issuance costs	1,334	4,511
Other current liabilities	2,379	2,553
Total current liabilities	8,508	11,657
Operating lease liability, less current portion	1,055	1,768
Total liabilities	9,563	13,425
Commitments and Contingencies
Stockholders’ equity (deficit):
Common stock, $0.001 par value; 300,000,000 shares authorized at December 31, 2023 and 2022; 20,222,672 and 16,840,261 shares issued and outstanding at December 31, 2023 and 2022, respectively	20	17
Additional paid-in capital	534,375	516,457
Accumulated other comprehensive loss	0	(12)
Accumulated deficit	(513,213)	(483,176)
Total stockholders’ equity	21,187	33,291
Total liabilities and stockholders’ equity	30,750	46,716
Class A-1 Convertible Preferred Stock
Stockholders’ equity (deficit):
Convertible preferred stock	0	0
Class A-2 Convertible Preferred Stock
Stockholders’ equity (deficit):
Convertible preferred stock	1	1
Class A-3 Convertible Preferred Stock
Stockholders’ equity (deficit):
Convertible preferred stock	0	0
Class A-4 convertible preferred stock outstanding (as-converted)
Stockholders’ equity (deficit):
Convertible preferred stock	4	4
Class A-5 convertible preferred stock outstanding (as-converted)
Stockholders’ equity (deficit):
Convertible preferred stock	$ 0	$ 0