Blueprint Medicines Soars 26.36% on Sanofi Acquisition

On June 2, 2025, Blueprint Medicines' stock surged by 26.36% in pre-market trading, driven by a significant acquisition announcement.

Sanofi has agreed to acquire Blueprint Medicines in a deal valued at approximately $9.1 billion. The acquisition includes key assets such as Ayvakit/Ayvakyt, elenestinib, and BLU-808, which are expected to bolster Sanofi's portfolio in rare immunological diseases, particularly systemic mastocytosis (SM).

Sanofi will pay $129.00 per share in cash for Blueprint Medicines, representing a 27% premium over the closing price of Blueprint shares on May 30, 2025. The transaction is anticipated to close in the third quarter of 2025, pending customary regulatory approvals.

Strategically, Sanofi expects the acquisition to be immediately accretive to its gross margin and to positively impact business operating income and earnings per share (EPS) after 2026. The acquisition will be financed through a combination of cash on hand and new debt, while maintaining capacity for future acquisitions.