CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating activities
Net loss	$ (83,838)	$ (69,204)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of premium (accretion of discounts) on marketable securities	(296)	1,270
Depreciation and amortization	1,047	996
Stock-based compensation expense	11,264	9,952
Gain on foreign currency translation	627	258
Non- cash operating lease expense	1,760	0
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(1,421)	(1,764)
Accounts payable, accrued expenses, and other current liabilities	3,710	933
Deferred revenue	(1,527)	(3,432)
Deferred rent, net of current portion	0	(35)
Operating lease liabilities	(2,097)	0
Net cash used in operating activities	(70,771)	(61,026)
Investing activities
Purchase of marketable securities	(190,856)	(164,977)
Proceeds from maturities of marketable securities	146,211	84,385
Proceeds from sale of equipment	0	0
Purchase of property and equipment	(845)	(755)
Net cash used in investing activities	(45,490)	(81,347)
Financing activities
Proceeds from issuances of common stock under employee stock plans	1,392	2,022
Net cash provided by financing activities	131,180	141,482
Net increase (decrease) in cash and cash equivalents	14,919	(891)
Cash and cash equivalents at beginning of year	24,027	24,918
Cash and cash equivalents at end of year	38,946	24,027
Supplemental disclosures of non-cash investing and financing information
Right-of-use asset obtained in exchange for lease obligation	8,063	0
Public Offering
Financing activities
Proceeds from equity offerings, net of issuance costs	124,810	134,770
At The Market
Financing activities
Proceeds from equity offerings, net of issuance costs	$ 4,978	$ 4,690