Segment Reporting (Details) $ in Thousands		3 Months Ended		6 Months Ended
	Mar. 04, 2026 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) segment	Jun. 30, 2025 USD ($)
Segment Reporting
Number of reportable segments | segment				1
Research and development
Total research and development expenses		$ 3,343	$ 5,814	$ 7,436	$ 13,551
General and administrative
Total general and administrative expenses		6,873	4,520	11,660	10,605
Impairment of long-lived assets					2,637
Net gain on lease terminations	$ (600)	(1,944)		(2,577)
Loss from operations		(8,272)	(10,334)	(16,519)	(26,793)
Other income (expense), net		451	949	1,139	2,003
Net loss		(7,821)	(9,385)	(15,380)	(24,790)
Genetic Medicines Segment
Research and development
Wages, benefits, and other payroll		1,830	1,302	3,288	4,891
Third-party costs		1,464	4,154	3,896	7,948
Share-based compensation		49	248	191	492
Depreciation and amortization			110	61	220
Total research and development expenses		3,343	5,814	7,436	13,551
General and administrative
Wages, benefits, and other payroll		2,312	1,798	4,203	4,588
Third-party costs		4,059	1,974	6,474	4,577
Share-based compensation		476	675	890	1,289
Depreciation and amortization		26	73	93	151
Total general and administrative expenses		6,873	4,520	11,660	10,605
Impairment of long-lived assets					2,637
Net gain on lease terminations		(1,944)		(2,577)
Loss from operations		(8,272)	(10,334)	(16,519)	(26,793)
Other income (expense), net		451	949	1,139	2,003
Net loss		$ (7,821)	$ (9,385)	$ (15,380)	$ (24,790)