A major change has just occurred at Sanofi. The board of directors decided not to renew Paul Hudson’s contract as CEO, which means he will step down from the role on February 17, 2026 after six years of leading the company.

What’s interesting here is who will replace him. Belén Garijo, who comes from having served as CEO of Merck KGaA since 2021, will take the reins. She will become the new CEO once the annual general meeting concludes on April 29, 2026. In the meantime, Olivier Charmeil will take over as interim CEO during the transition.

The board is being quite clear about its expectations. Garijo will bring “greater rigor” to Sanofi’s strategy and will focus on three areas: productivity, governance, and innovation in R&D. This sounds like a fairly marked shift in direction compared with what Paul Hudson was doing.

Now, why is this happening? Reuters notes that Paul Hudson faced constant pressure during his tenure. Although he was brought in to revitalize the drug portfolio and the share price, he failed to reduce Sanofi’s dependence on a single drug: Dupixent. This eczema treatment is practically the core of the current business.

The numbers say it all. Dupixent generated €4.2 billion in the fourth quarter of 2025, with growth of 32.2%. It’s an impressive figure, but also the problem. Sanofi’s CFO, François-Xavier Roger, was very direct in his remark: the loss of Dupixent’s exclusivity is too large to offset with other products. That is enormous pressure.

In the vaccines segment, things also haven’t gone well. Sales fell 2.5% to €2.0 billion. Beyfortus dropped 14.9%, and primary vaccines against Polio/Diphtheria/Tetanus/Hib fell 9.5%, mainly due to fewer births in countries such as China. The only positive note was that flu and influenza/COVID vaccines rose 31.5%.

Paul Hudson’s strategy seemed to be betting that amlitelimab, a drug in development, could succeed Dupixent. Sanofi has generated solid data for patients aged 12 years and older with moderate to severe atopic dermatitis, but clearly the board felt this was not enough.

The market has already reacted. Sanofi’s shares fell 6.25% to $46.17 in pre-market trading. Investors are processing this change and what it means for the company’s future under the leadership of Belén Garijo.