Segment Information - Schedule of Disaggregated Amounts of Research and Development Expenses and General and Administrative Expenses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Research and development:
Total research and development expenses	$ 6,669	$ 5,653	$ 12,630	$ 9,693
General and administrative:
Total general and administrative expense	5,115	1,705	11,233	4,460
Direct Program Costs
Research and development:
Total research and development expenses	5,372	4,879	9,896	7,988
Personnel Related
Research and development:
Total research and development expenses	1,045	774	2,180	1,648
General and administrative:
Total general and administrative expense	1,467	589	3,529	1,328
Stock-Based Compensation
Research and development:
Total research and development expenses	142	0	303	57
General and administrative:
Total general and administrative expense	769	0	1,484	0
Other
Research and development:
Total research and development expenses	110	0	251	0
Consulting and Professional Services
General and administrative:
Total general and administrative expense	1,496	645	3,473	2,301
Facilities Related and Other
General and administrative:
Total general and administrative expense	$ 1,383	$ 471	$ 2,747	$ 831