Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2023
Cash flows from operating activities:
Net loss	$ (11,227)	$ (16,556)	$ (20,313)	$ (21,658)	$ (41,487)	$ (63,518)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization					721	781
Stock-based compensation					7,336	9,704
Amortization of premiums and discounts on marketable securities					(1,769)	(4,128)
Amortization of debt discount and issuance costs and other non-cash interest					238	193
Impairment loss of right-of-use asset					0	1,549	$ 2,700
Reclassification of currency translation loss					282	0
Gain on disposition of fixed assets					(4)	0
Changes in operating assets and liabilities
Prepaid expenses and other current assets					958	(2,413)
Other assets					2,415	3,180
Accounts payable, accrued and other current liabilities					(6,748)	(1,607)
Operating lease assets and liabilities					(1,757)	(1,128)
Net cash used in operating activities					(39,815)	(57,387)
Cash flows from investing activities:
Purchases of property and equipment					(8)	(18)
Proceeds from sale of fixed assets					9	0
Purchases of marketable securities					(42,631)	(72,102)
Maturities of marketable securities					83,481	128,804
Net cash provided by investing activities					40,851	56,684
Cash flows from financing activities:
Repayment of loan principal					(3,913)	0
Proceeds from issuance of common stock under employee stock incentive plans					35	56
Net cash (used in) provided by financing activities					(3,878)	56
Effect of exchange rate changes on cash and cash equivalents					28	12
Net decrease in cash and cash equivalents					(2,814)	(635)
Cash and cash equivalents at the beginning of period		$ 41,749		$ 35,493	41,749	35,493
Cash and cash equivalents at the end of period	$ 38,935		$ 34,858		38,935	34,858	$ 35,493
Supplemental disclosures
Cash paid for interest					$ 667	$ 1,011