09:40 AM EDT, 06/02/2025 (MT Newswires) -- Sanofi ( SNY ) agreed to acquire biopharmaceutical company Blueprint Medicines ( BPMC ) in a deal worth up to $9.5 billion, as the French drugmaker seeks to expand its immunology portfolio.

Sanofi ( SNY ) will initially pay $129 per share in cash through a tender offer to acquire US-based Blueprint Medicines ( BPMC ), representing an equity value of about $9.1 billion.

For each share owned, Blueprint stockholders will also be eligible for $2 and $4 in clinical and regulatory milestone payments, respectively, regarding its BLU-808 drug candidate being studied for the treatment of diseases in immunology. The total equity value of the deal, including milestone payments, is about $9.5 billion.

The proposed acquisition would give Sanofi ( SNY ) access to rare immunology disease medicine Ayvakit/Ayvakyt, systemic mastocytosis treatment candidate elenestinib, and BLU-808.

"The proposed acquisition of Blueprint Medicines ( BPMC ) represents a strategic step forward in our rare and immunology portfolios," Sanofi ( SNY ) Chief Executive Paul Hudson said in a joint statement released Monday. "It enhances our pipeline and accelerates our transformation into the world's leading immunology company."

The deal is subject to regulatory approvals and majority of Blueprint shareholders tendering their shares in the tender offer. Sanofi ( SNY ) expects to complete the acquisition in the third quarter.

Sanofi's ( SNY ) Nasdaq-listed shares were down 0.2% in Monday trade, while Blueprint Medicines ( BPMC ) soared 26%.

In May 2023, Blueprint announced the US Food and Drug Administration approved Ayvakit for adults with indolent systemic mastocytosis, followed by its approval by the European Commission in December of the same year. The product's net revenue in the first quarter was about $150 million, up over 60% year over year. In 2024, its sales came in at $479 million.

The deal will be accretive to Sanofi's ( SNY ) earnings per share after 2026, and will not have a "significant impact" on its 2025 guidance, the company said.

"With this agreement, we begin our next chapter with Sanofi ( SNY ), whose exceptional leadership in rare disease and immunology and proven ability to solve medical challenges at scale stand to accelerate our joint mission to bring life-changing medicines to many more patients around the world," Blueprint Chief Executive Kate Haviland said.