Condensed Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net loss	$ (9,139)	$ (5,387)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	351	322
Share-based compensation	1,074	185
Deferred rent	(3)
Forgiveness of PPP Loan	(500)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	142	186
Accounts payable	486	874
Accrued expenses and other current liabilities	313	276
Net cash used in operating activities	(7,276)	(3,544)
Cash flows from investing activities:
Purchases of property and equipment	(39)	(416)
Net cash used in investing activities	(39)	(416)
Cash flows from financing activities:
Proceeds from sale of Series A convertible preferred stock		11,046
Payment of Series A convertible preferred stock issuance costs		(27)
Proceeds from sale of common stock and common stock warrants	27,000
Payment of issuance costs releated to the sale of common stock and common stock warrants	(486)
Proceeds from exercise of stock options	27	3
Proceeds from exercise of stock warrants	906
Proceeds from long-term debt		500
Payment of equipment loan payable	(69)	(112)
Payment of capital lease obligations		(204)
Net cash provided by financing activities	27,378	11,206
Net decrease in cash and restricted cash	20,063	7,246
Cash and restricted cash at beginning of period	39,866	2,643
Cash and restricted cash at end of period	59,929	9,889
Supplemental disclosures of cash flow information:
Cash paid for interest		17
Supplemental disclosures of non-cash investing and financing activities:
Fair value of liability-classified warrants issued in connection with Series A convertible preferred stock		$ 1,522
Purchases of property and equipment in accounts payable	7
Offering costs in accounts payable	$ 110