Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net loss	$ (43,274)	$ (34,469)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization expense	558	640
Amortization of operating lease right-of-use assets	4,882	4,895
Stock-based compensation expense	4,254	3,412
Loss on disposal of equipment	42	6
Changes in operating assets and liabilities:
Accounts receivable	3,000	1,892
Prepaid expenses and other current assets	(369)	(386)
Accounts payable	(2,278)	(793)
Accrued expenses	2,901	(1,818)
Deferred revenue	(5,877)	(9,767)
Deferred financing costs	13
Operating lease liabilities	(4,762)	(4,609)
Net cash used in operating activities	(40,910)	(40,225)
Cash flows from investing activities:
Purchases of property and equipment	(308)	(521)
Proceeds from disposals of property and equipment	34
Cash flows from investing activities	(274)	(521)
Cash flows from financing activities:
Proceeds from issuance of common stock		56,400
Payment of issuance costs		(1,904)
Proceeds from Issuance of Common Stock		56,400
Proceeds from issuance of common stock under at-the market offering	3,092
Proceeds from issuance of common stock under employee stock purchase plan	111
Proceeds from exercise of stock options	29	960
Net cash provided by financing activities	3,232	55,456
Net (decrease) increase in cash, cash equivalents and restricted cash	(37,952)	14,710
Cash, cash equivalents and restricted cash at beginning of period	145,818	172,662
Cash, cash equivalents and restricted cash at end of period	107,866	$ 187,372
Supplemental disclosure of non-cash investing and financing activities:
Deferred offering costs included in accrued expenses at end of period	$ 106