Published on: April 20, 2026 – Keith Chappell, Scientific Advisor at Sanofi
Most people don’t think about how a vaccine is designed. They think about the appointment, the needle, maybe a sore arm later that day. But behind the scenes, scientists are working through a surprisingly delicate question: to design a more effective vaccine, how do you show the immune system what a virus really looks like?
This question matters more than most of us realize. Consider respiratory syncytial virus (RSV). Most RSV infections resemble the common cold. But globally, RSV triggers 33 million severe respiratory infections in young children each year, with 95% occurring in low- and middle-income countries. And in older adults, RSV is increasingly recognized as a serious cause of hospitalization, with disease severity that can rival influenza in vulnerable populations.
For Keith Chappell, Scientific Advisor at Sanofi, this burden pointed to a challenge he’s been trying to solve for more than a decade: how to capture a moving target.
Viral proteins can act as shapeshifters, posing a key challenge in the development of effective vaccines, as the immune system recognizes viruses by their shape.
The molecular clamp, developed by Sanofi, is a small synthetic scaffold that stabilizes viral proteins in their most potent shape. This allows the immune system to better recognize the threat and respond accordingly. This “plug-and-play” approach can accelerate the development of new vaccines, including combinations, and support pandemic preparedness.
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Discover the full article and learn more about the science behind molecular clamp vaccines via Sanofi.
