The U.S. Food and Drug Administration (FDA) has released new draft guidance that emphasizes overall survival (OS) as the preferred primary endpoint in cancer clinical trials whenever it is feasible. This marks a significant shift from the previous reliance on surrogate endpoints, such as tumor shrinkage or progression-free survival, which often promised faster approvals but did not always translate into longer patient lives.
For years, many treatments moved quickly through regulatory pathways based on intermediate measures. While efficient, this approach carried an important limitation: some drugs that slowed tumor progression failed to meaningfully extend survival. The FDA’s updated stance addresses this critical gap by placing patient outcomes, not just clinical metrics, at the heart of cancer research.
At its core, this is about understanding what matters most to patients. When individuals sit across from their oncologists, their primary concern is not whether a tumor marker improves but whether a treatment will help them live longer and spend more time with their loved ones. The new guidance aligns regulatory expectations with these patient-centered priorities, representing a significant step toward designing trials that reflect real-world values.
However, the FDA also acknowledges that measuring overall survival is not always practical. In cases involving indolent cancers or diseases with long survival times, waiting for OS data could be unfeasible. In such scenarios, sponsors may continue to use alternative endpoints but must clearly justify why overall survival cannot be the focus.
This shift raises an important question for sponsors and researchers alike: Are clinical trials being designed around what patients truly value? As the gap between traditional measurements and patient-centered outcomes narrows, it becomes increasingly difficult to ignore the need for evidence that directly reflects improvements in both life span and quality of life.
While this transition may introduce challenges for trial designs and timelines, it signals a promising move toward ensuring that future cancer therapies deliver what patients need most more meaningful time.
Source: U.S. Food and Drug Administration (FDA) – Draft Guidance, August 2025
SUBMIT YOUR COMMENT