CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Operating activities
Net loss	$ (39,652)	$ (32,624)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of premium on marketable securities	507	430
Depreciation and amortization	535	536
Stock-based compensation expense	5,374	5,575
Gain on foreign currency translation	349	108
Non-cash operating lease expense	854	0
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	562	(563)
Accounts payable, accrued expenses and other current liabilities	3,300	471
Deferred revenue	(1,527)	(1,709)
Deferred rent	0	(50)
Operating lease liabilities	(1,075)	0
Net cash used in operating activities	(30,773)	(27,826)
Investing activities
Purchase of marketable securities	(72,241)	(118,705)
Proceeds from maturities of marketable securities	86,335	67,715
Purchase of property and equipment	(715)	(291)
Net cash provided by (used in) investing activities	13,379	(51,281)
Financing activities
Proceeds from equity offerings, net of issuance costs	49,784	134,582
Proceeds from issuance of common stock under employee stock plans	786	1,137
Net cash provided by financing activities	50,570	140,409
Net increase inn cash and cash equivalents	33,176	61,302
Cash and cash equivalents at beginning of period	24,027	24,918
Cash and cash equivalents at end of period	57,203	86,220
Supplemental disclosures of non-cash investing and financing information
Right-of-use asset obtained in exchange for lease obligation	(6,585)	0
Issuance costs related to public offering included in accrued expenses		403
At The Market
Financing activities
Proceeds from equity offerings, net of issuance costs	$ 0	$ 4,690