Progression-Free vs Overall Survival

Progression-free vs overall survival is the clinical-endpoint distinction emphasized in 156.生物医药的2026：当市场不再为BD躁动，中国药企的星辰大海才刚刚展开. 小P老师 explains PFS as time before disease progression, while OS asks whether patients live longer overall.

The distinction matters because a drug can shrink tumors or delay progression without yet proving a dramatic survival extension. The source applies this to 康方生物, Summit, and PD-1/VEGF bispecific interpretation: strong PFS can justify attention, but OS is harder to read and more decisive for the market’s strongest claims.

Key Claims

• PFS can respond more directly to tumor shrinkage and progression delay.
• OS is more patient-direct but can be confounded by follow-on treatment, patient condition, and trial design.
• A trial whose primary endpoint is PFS should not be interpreted as if it had already proven exceptional OS.
• Endpoint interpretation is central to Biotech BD Data Validation Phase because BD assets need more than one attractive number.

Connections

• PD-1/VEGF Bispecific, Akeso / 康方生物, and Summit Therapeutics - source case.
• Clinical Development Capability - trial design and endpoint strategy.
• Medical Risk Management - caution around interpreting incomplete evidence.