Sanofi to fork out $9 million + to buy Blueprint Medicines

French pharma major Sanofi (Euronext: SAN) today revealed an agreement to acquire, and Blueprint Medicines (Nasdaq: BPMC), a US company, specializing in systemic mastocytosis (SM), a rare immunological disease, and other KIT-driven diseases. Blueprint’s shares soared 26.80% to $101.35 in pre-market activity today.

The acquisition includes a rare immunology disease medicine, Ayvakit/Ayvakyt (avapritinib), approved in the USA and the European Union, and a promising advanced and early-stage immunology pipeline. Furthermore, Blueprint’s established presence among allergists, dermatologists, and immunologists is expected to enhance Sanofi’s growing immunology pipeline. Ayvakit achieved net revenues of $479 million in 2024 and nearly $150 million in first-quarter 2025, representing year-on-year growth of more than 60% over first-quarter 2024.

Ayvakit/Ayvakyt is the only approved medicine for advanced and indolent systemic mastocytosis (ASM & ISM), a rare immunology disease, which is characterized by the accumulation and activation of aberrant mast cells in bone marrow, skin, the gastrointestinal tract, and other organs. The acquisition will also bring elenestinib, a next-generation medicine for SM, as well as BLU-808, a highly selective and potent oral wild-type KIT inhibitor that has the potential to treat a broad range of diseases in immunology.