Mast cells drive Blueprint mega-deal

Abstract

In one of the biggest biopharma deals of 2025, Sanofi has acquired Blueprint Medicines for a $9.1 billion upfront payment. The agreement gives the Paris-based pharma an approved drug for systemic mastocytosis as well as a broad pipeline that will bolster the company’s presence in immunological diseases. Blueprint Medicines launched in 2011 with series A funding from Third Rock Ventures and F-Prime Capital, and went public in 2015. It has been developing potent tyrosine kinase inhibitors using novel chemistry from its proprietary compound library and artificial intelligence to enhance its drug discovery processes.

Blueprint gained its first approval in 2020 for oral tyrosine kinase inhibitor Ayvakit (avapritinib), for treating gastrointestinal stromal tumors. The US Food and Drug Administration later granted label expansions in 2021 for advanced and then indolent systemic mastocytosis in 2023. Blueprint estimates that about 30,000–60,000 patients have systemic mastocytosis, a rare disorder that leads to the accumulation of mast cells in various organs and tissues, in the United States alone.