Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (79,464)	$ (68,741)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	1,504	1,208
Amortization of operating lease right-of-use assets	10,180	9,822
Stock-based compensation expense	8,403	8,505
Loss on disposal of property and equipment	33	7
Changes in operating assets and liabilities:
Accounts receivable	3,000	(1,108)
Prepaid expenses and other current assets	(373)	460
Accounts payable	(1,422)	1,074
Accrued expenses	2,083	(283)
Accrued restructuring expenses	3,162
Deferred revenue	(20,988)	(23,873)
Other assets	323	(323)
Operating lease liabilities	(9,990)	(8,710)
Other liabilities		(175)
Net cash used in operating activities	(83,549)	(82,137)
Cash flows from investing activities:
Purchases of property and equipment	(522)	(613)
Proceeds from sale of equipment	34
Net cash used in investing activities	(488)	(613)
Cash flows from financing activities:
Proceeds from issuance of common stock under at-the market offering of common stock, net of issuance costs	4,067
Proceeds from follow-on public offering of common stock, net of issuance costs		56,400
Payment of public offering costs		(1,904)
Proceeds from issuance of common stock under employee stock purchase plan	29	103
Proceeds from exercise of stock options	137	1,307
Net cash provided by financing activities	4,233	55,906
Net (decrease) increase in cash, cash equivalents and restricted cash	(79,804)	(26,844)
Cash, cash equivalents and restricted cash at beginning of period	145,818	172,662
Cash, cash equivalents and restricted cash at end of period	66,014	145,818
Supplemental disclosure of non-cash investing and financing activities:
Lease assets obtained in exchange for operating lease liabilities		$ 31,307
Reduction in lease assets and liabilities due to lease amendment	$ (32,230)