Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 38,320	$ 66,923
Inventories	906	2,352
Prepaid expenses and other current assets	1,782	1,448
Total current assets	41,008	70,723
Restricted cash	1,960	1,311
Property and equipment, net	1,488	1,841
Right-of-use lease asset	4,224	4,706
Other assets		1,543
Total assets	48,680	80,124
Current liabilities:
Accounts payable, net	2,372	4,547
Accrued expenses and other current liabilities	5,461	3,847
Lease liability	899	792
Total current liabilities	8,732	9,186
Loans payable, net	13,430
Leases, net of current portion	5,436	6,309
Warrant liability	5,483
Total liabilities	33,081	15,495
Stockholders' equity:
Preferred stock-$0.001 par value; 5,000,000 shares authorized, none issued or outstanding at December 31, 2022 and December 31, 2021
Common stock-$0.001 par value; 200,000,000 shares authorized at December 31, 2022 and December 31, 2021; 7,744,692 and 6,618,093 shares issued and outstanding at December 31, 2022 and December 31, 2021, respectively	8	7
Additional paid-in capital	563,362	558,724
Accumulated deficit	(547,772)	(494,102)
Accumulated other comprehensive loss	1
Total stockholders' equity	15,599	64,629
Total liabilities and stockholders' equity	$ 48,680	$ 80,124