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Stock-Based Compensation - Schedule of Total Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 9,378	$ 8,682	$ 18,237	$ 22,517
Stock-based compensation		8,700	18,237	22,517
Aeglea Employees and Directors
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Stock-based compensation		700		3,800
Parapyre Option Obligation
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Stock-based compensation		1,500		6,900
Research and development
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	4,100	3,451	7,612	10,308
General and administrative
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 5,278	$ 5,231	$ 10,625	$ 12,209