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Organization and Principal Activities - Additional Information (Details) $ / shares in Units, $ in Thousands			6 Months Ended
	Feb. 09, 2026 USD ($) $ / shares shares	Dec. 02, 2025	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Date of incorporation			Apr. 21, 2003
Headquartered in			South San Francisco
Headquartered in state			CA
Proceeds from issuance of common stock			$ 102,658	$ 0
Accumulated deficit			1,054,972		$ 977,955
Unrestricted cash, cash equivalents and marketable securities			$ 164,300
Reverse stock split		0.1
Employee Severance \| March and September 2025 Restructuring Plan
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Restructuring plan, percentage of workforce reduction			0.6667%
Minimum
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Period from issuance date of unaudited interim condensed financial statements			12 months
Common Stock \| Leerink Partners LLC and TD Securities (USA) LLC
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Shares of common stock \| shares	7,868,383
Offering price \| $ / shares	$ 13.98
Proceeds from issuance of common stock	$ 110,000