Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Consolidated net loss	$ (11,952)	$ (12,154)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	80	81
Stock-based compensation	619	417
(Accretion) amortization of (discount) premium of available-for-sale investment securities	(419)	237
Amortization of right-of-use assets	675	217
Gain on disposal of property and equipment	0	(89)
Changes in operating assets and liabilities:
Other receivables	9,883	9
Prepaid expenses and other assets	(438)	1,180
Accounts payable and accrued expenses	(1,057)	216
Operating lease liability	2,019	(233)
Net cash used in operating activities	(590)	(10,119)
Cash flows from investing activities:
Purchases of property and equipment	(1,246)	(43)
Purchases of available-for-sale investment securities	(46,226)	0
Maturities of available-for-sale investment securities	9,300	14,500
Proceeds from sale of property and equipment	0	169
Net cash (used in) provided by investing activities	(38,172)	14,626
Cash flows from financing activities:
Proceeds from issuance of common stock through option exercises	0	1
Proceeds from issuance of common stock from at-the-market offerings, net of offering costs	1,489	1,480
Proceeds from issuance of common stock from underwritten follow-on public offering, net of offering costs	48,073	0
Principal paid on finance lease liabilities	(66)	0
Net cash provided by financing activities	49,496	1,481
Net change in cash, cash equivalents and restricted cash	10,734	5,988
Cash, cash equivalents and restricted cash at beginning of period	13,146	2,336
Cash, cash equivalents and restricted cash at end of period	23,880	8,324
Cash and cash equivalents at the end of period	20,690	8,324
Restricted cash at the end of period	3,190	0
Cash, cash equivalents and restricted cash at the end of period	23,880	8,324
Supplemental disclosure of cash flow information:
Interest paid	46	0
Purchases of property and equipment in accounts payable	2,136	0
Right-of-use assets obtained in exchange for lease obligation	$ 1,043	$ 0