Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 131,177	$ 142,072
Accounts receivable, net	3,673	2,560
Inventory	5,261	3,880
Prepaid expenses and other current assets	2,090	2,585
Total current assets	142,201	151,097
Property and equipment, net	1,656	1,425
Operating lease right-of-use asset	522	0
Other non-current assets	26	26
Total assets	144,405	152,548
Current liabilities:
Accounts payable	1,607	510
Accrued expenses	4,985	5,398
Total current liabilities	6,592	5,908
Operating lease liability, non-current portion	304	0
Other long-term liabilities	706	681
Total liabilities	7,602	6,589
Commitments and contingencies (Notes 5 and 10)
Stockholders' equity
Common stock, $0.01 par value, 200,000,000 authorized as of March 31, 2022 and December 31, 2021; 20,486,971 and 20,399,337 shares issued and outstanding as of March 31, 2022 and December 31, 2021, respectively	205	204
Additional paid-in capital	541,547	540,707
Accumulated deficit	(404,745)	(394,754)
Accumulated other comprehensive loss	(204)	(198)
Total stockholders' equity	136,803	145,959
Total liabilities and stockholders' equity	$ 144,405	$ 152,548