Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (29,079)	$ (27,631)
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Depreciation and amortization	538	587
Stock-based compensation	4,520	4,305
Amortization of premium and discount on marketable securities	(2,414)	(190)
ROU asset amortization	884	833
Gain on disposal of equipment	0	(70)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	5,301	639
Accounts payable	(1,076)	1,894
Accrued expenses	(6,046)	(3,033)
Operating lease liability	(892)	(818)
Net cash used in operating activities	(28,264)	(23,484)
Cash flows from investing activities:
Purchases of property and equipment	(21)	(158)
Purchases of marketable securities	(110,339)	(117,332)
Proceeds from sale or maturities of marketable securities	131,011	12,760
Proceeds from sale of equipment	0	176
Net cash provided by (used in) investing activities	20,651	(104,554)
Cash flows from financing activities:
Proceeds from exercise of stock options	62	5
Proceeds from issuance of common stock	(3,126)	0
Issuance costs from issuance of common stock	(95)	0
Net cash provided by financing activities	3,093	5
Net change in cash and cash equivalents	(4,520)	(128,033)
Cash and cash equivalents at beginning of period	34,946	144,514
Cash and cash equivalents at end of period	30,426	16,481
Supplemental disclosure of cash flow information
Unrealized loss on marketable securities	$ 128	$ 641