Sanofi to Acquire Blueprint Medicines for Up to $9.5 Billion, Expanding Immunology Focus

Sanofi announced on June 2, 2025, that it will acquire Blueprint Medicines for up to $9.5 billion, paying $129 per share, a 27% premium over Blueprint’s closing price on May 30, 2025234.

The acquisition strengthens Sanofi’s immunology pipeline, notably adding Ayvakit (avapritinib), the only approved treatment for advanced and indolent systemic mastocytosis (SM), a rare immunological disease, in the US and EU234.

Sanofi will also obtain Blueprint’s next-generation SM candidate elenestinib, currently in Phase 2/3 trials, and early-stage KIT inhibitor BLU-808, potentially broadening their reach in immunological and KIT-driven diseases24.

The deal follows Sanofi’s sale of its consumer health business Opella and aligns with its stated strategy to focus on bolt-on acquisitions and boost its rare disease and immunology portfolios23.

Sanofi’s acquisition includes both guaranteed cash and potential future milestone payments, with total deal value reaching up to $9.5 billion34.

Sanofi expects to complete the acquisition in the third quarter of 2025, enhancing its relationships among allergists, dermatologists, and immunologists through Blueprint’s established presence4.

Sources:

2. https://www.fiercepharma.com/pharma/opella-sale-burning-hole-its-pocket-sanofi-snaps-blueprint-95b

3. https://www.investopedia.com/blueprint-medicines-stock-soars-as-biotech-agrees-to-over-9b-sanofi-takeover-11746204

4. https://www.globenewswire.com/news-release/2025/06/02/3091539/0/en/Press-Release-Sanofi-to-acquire-Blueprint-Medicines-expanding-portfolio-in-rare-immunological-disease-and-adding-early-stage-pipeline-in-immunology.html