Condensed Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net loss	$ (37,494)	$ (34,045)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	87	450
Change in fair value of derivative liability associated with contingently issuable warrants	(109)
Non-cash interest expense related to term loan	350
Stock-based compensation expense	4,631	5,133
Changes in operating assets and liabilities:
Prepaid expenses and other assets	1,887	3,692
Accounts receivable		257
Accounts payable	1,406	(775)
Accrued expenses and other liabilities	(1,440)	(467)
Net cash used in operating activities	(30,682)	(25,755)
Cash flows from investing activities:
Proceeds from sale of property and equipment		121
Net cash provided by investing activities		121
Cash flows from financing activities:
Proceeds from stock options exercised		133
Repurchase of shares for tax withholdings		(912)
Proceeds from issuance of term loan, net of issuance costs paid to lender	10,000
Payment of debt issuance costs	(20)
Proceeds from at the market offering, net of sales commission		14,615
Payment of offering costs	(153)	(4)
Net cash provided by financing activities	9,827	13,832
Net (decrease) in cash, cash equivalents and restricted cash	(20,855)	(11,802)
Cash, cash equivalents and restricted cash, at beginning of period	106,321	141,299
Cash, cash equivalents and restricted cash, at end of period	85,466	$ 129,497
Supplemental disclosure of cash flow information:
Cash paid for interest	798
Supplemental disclosure of non-cash investing and financing activities:
Deferred offering costs not yet paid	78
Issuance of warrants in connection with term loan financing	$ 206