Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities
Net loss	$ (6,145)	$ (2,363)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	16	22
Non-cash stock-based compensation	764	361
Amortization of financing lease right-of-use assets	149	113
Amortization of operating lease right-of-use assets	67	30
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	792	(162)
Other current assets		(52)
Accounts payable	158	(180)
Accrued expenses and other current liabilities	(351)	(298)
Short-term operating lease liabilities	72	57
Long-term operating lease liabilities	(81)	(35)
Net cash used in operating activities	(4,559)	(2,507)
Investing activities
Purchases of property and equipment	(8)
Construction in progress	(245)
Net cash used in investing activities	(253)
Financing activities
Principal payments on financing leases	(135)	(112)
Exercise of common stock	33
Deferred offering costs paid		(323)
Net cash provided by financing activities	(102)	(435)
Net increase in cash and restricted cash	(4,914)	(2,942)
Cash and restricted cash at beginning of period	37,272	17,994
Cash and restricted cash at end of period	32,358	15,052
Cash, end of period	32,107	15,052
Restricted cash, end of period	251
Cash and restricted cash, end of period	32,358	15,052
Supplemental disclosure of non-cash operating, financing and investing information
Deferred offering costs included in accounts payable and accrued expenses		1,238
Initial measurement of operating lease right-of-use assets and liabilities		$ 3,483