The fourth quarter of 2025 saw significant activity in the biopharma mergers and acquisitions space, highlighted by several major deals involving both large pharmaceutical companies and smaller biotech firms.
Novartis led the quarter with its $11.3 billion acquisition of Avidity Biosciences, a company specializing in neuromuscular disorders. The deal was notable for its negotiation process; at one point, Avidity CEO Sarah Boyce and her team halted talks with Novartis and shifted focus to raising capital before ultimately reaching an agreement.
Other billion-dollar transactions included Merck's $9.2 billion purchase of Cidara Therapeutics and Novo Nordisk's acquisition of Akero Therapeutics for $4.9 billion. Sanofi entered into a $2.2 billion deal to acquire Dynavax, which brings an approved hepatitis B vaccine called Heplisav-B as well as a singles vaccine candidate to Sanofi's portfolio. BioMarin made a $4.8 billion offer for Amicus Therapeutics, aiming to add two approved rare disease therapies.
Smaller companies were also active in M&A this quarter. Alkermes, with a market capitalization of approximately $4.6 billion, acquired sleep disorder biotech Avadel for $2.1 billion after competing with Lundbeck in a brief bidding war.
According to S&P Capital IQ’s database, there were 20 announced deals during the quarter. Notably absent from this list is Pfizer’s acquisition of Metsera for $9.8 billion, as that deal was finalized in the previous quarter.
Additional transactions included Mirum Pharmaceuticals’ acquisition of Bluejay Therapeutics for $805 million, focusing on brelovitug—a Phase III antibody targeting chronic hepatitis delta virus (HDV). XOMA Royalty offered to buy Generation Bio for $55 million after Generation Bio faced significant layoffs earlier in the year; XOMA is recognized for acquiring struggling biotech firms and breaking them down for remaining value.
For further analysis on recent industry trends and additional quarterly roundups from 2025, readers can find more information on BioSpace’s website.
