Sanofi has agreed to acquire Blueprint Medicines for up to approximately $9.5 billion, the companies said today, in a deal designed to expand the buyer’s rare immunological disease portfolio with an FDA-approved treatment, as well as an early-stage pipeline of immunological drug candidates.
The deal includes Blueprint’s marketed drug Ayvakit® (avapritinib), a selective inhibitor of activated KIT and PDGFRA mutant kinases and the only approved therapy for advanced and indolent systemic mastocytosis (SM). Ayvakit is also indicated for gastrointestinal stromal tumor (GIST).
Ayvakit—marketed in the European Union as Ayvakyt®—generated net product revenues of $478.95 million in 2024, more than double the $204.207 million racked up a year earlier, plus $149.4 million during the first quarter, up 61.5% from $92.5 million in Q1 2024.
“The proposed acquisition of Blueprint Medicines represents a strategic step forward in our rare and immunology portfolios. It enhances our pipeline and accelerates our transformation into the world’s leading immunology company,” Sanofi CEO Paul Hudson said in a statement. “This acquisition is fully aligned with our strategic intent to strengthen our existing therapeutic areas, to bring relevant and differentiated medicines to patients and to secure attractive returns to our shareholders. It complements recent acquisitions of early-stage medicines that remain our main field of interest.
Blueprint investors appear to agree, as the company’s shares jumped 26% in premarket trading this morning. Sanofi shares on Euronext Paris, however, dipped 1.5% from €87.52 ($99.85) to €86.24 ($98.39) as of 9:06 a.m. ET.
Hudson also said that Sanofi still retained a “sizeable” capacity for further acquisitions. Sanofi last year grew its immunology and inflammation pipeline by acquiring Inhibrx for up to approximately $2.2 billion. The deal gave Sanofi access to Inhibrx’s mid-clinical-phase recombinant human AAT-Fc fusion protein therapeutic, which is being developed to treat Alpha-1 Antitrypsin Deficiency (AATD).
Sanofi may face competition in SM: Jefferies analyst Michael J. Yee reported in a research note this morning that investors anticipate Cogent Biosciences will report Phase III data in the second half of this year on its lead pipeline candidate bezuclastinib, which is also being developed for SM (both advanced and non-advanced) and GIST.
Hudson also said that Sanofi still retained a “sizeable” capacity for further acquisitions.
“We are excited to welcome Blueprint’s talented people and we look forward to chasing the miracles of science together,” Hudson added. “This makes sense for science, for both companies, for healthcare professionals, and—most of all—for patients.”
Through the deal, Sanofi will add to its immunology pipeline with elenestinib, a next-generation, highly selective KIT D816V inhibitor with limited central nervous system penetration; and BLU-808, a highly selective oral wild-type KIT inhibitor that according to the companies could potentially treat a wide variety of immunological diseases.
Elenestinib is being evaluated in the Phase II/III HARBOR trial (NCT04910685), an ongoing, randomized, double-blind, placebo-controlled study designed to assess the efficacy and safety of elenestinib plus symptom-directed therapy in patients with indolent SM and smoldering SM.
BLU-808 is a selective wild-type KIT inhibitor developed through Blueprint’s expertise in mast cell biology. Wild-type KIT plays a central role in mast cell activation, which is implicated in a broad range of inflammatory diseases.
Tender offer plus milestones
Upon closing of the deal, Sanofi has agreed to commence a tender offer to acquire all outstanding shares of Blueprint for $129 per share cash, for a total value of approximately $9.1 billion. The share price represents a premium of approximately 27% over the closing price of Blueprint on May 30, and a premium of approximately 34% over the 30 trading days volume weighted average price (VWAP) of Blueprint as of May 30.
Blueprint shareholders will also receive one non-tradeable contingent value right (CVR) that will entitle them to receive potential milestone payments of $2 per CVR tied to achieving a future development milestone for BLU-808, and $4 per CVR tied to achieving a future regulatory milestone for BLU-808. The milestones could generate up to an additional $400 million, bringing the deal’s total value to about $9.5 billion.
Together with the CVR, the premium is approximately 33% over the closing price on May 30, and approximately 40% over the 30 trading days VWAP.
Consummation of the tender offer is subject to customary closing conditions, including the tender of a number of shares of Blueprint common stock representing at least a majority of the outstanding shares of Blueprint common stock, the receipt of required regulatory approvals, and other customary conditions.
If the tender offer is successfully completed, a wholly owned subsidiary of Sanofi will merge with and into Blueprint and all outstanding Blueprint shares that are not tendered in the tender offer will be converted into the right to receive the same $129 per share cash and one CVR per share offered to Blueprint shareholders in the tender offer.
Sanofi said it plans to finance the transaction with a combination of cash on hand and proceeds from new debt. The tender offer is not subject to any financing condition.
Subject to the satisfaction or waiver of customary closing conditions, Sanofi said it expects to complete the acquisition in the third quarter. Sanofi said the acquisition will not have a significant impact on its financial guidance for 2025 and will immediately add to its gross margin.
The deal will also add to business operating income and earnings per share after 2026, Sanofi added.
“With this agreement, we begin our next chapter with Sanofi, 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,” stated Blueprint CEO Kate Haviland.
