Via the American Journal of Managed Care:
“A new study has analyzed data from randomized controlled trials (RCTs) in oncology that used surrogate endpoints and measured their relation with treatment effectiveness and patient survival in the real world.
A significant concern with using surrogate endpoints in clinical trials, especially in oncology, has been figuring out how they translate once the drugs are used in clinics post approval. Defined by the National Institutes of Health as a “biomarker intended to substitute for a clinical endpoint,” these intermediate markers substitute for a clinically meaningful endpoint and can be measured much earlier (such as time to progression [TTP], progression-free survival [PFS], etc.) and need a much smaller sample size and a shorter follow-up time.
For the study, the authors used data from 21 phase 3 RCTs that reported overall survival (OS) in addition to surrogates such as PFS or TTP endpoints in breast, colorectal, lung, ovarian, and pancreatic cancers. Using Surveillance and Epidemiology End Results-Medicare data, the researchers estimated real-world OS as the mortality hazard ratio (MHR) among patients meeting RCT inclusion criteria. The primary outcome was real-world OS.”