Top Biotech Deals in May 2026

Why It Matters

These transactions reshape therapeutic pipelines, giving large pharma direct access to niche rare‑disease, ophthalmology and vaccine assets, and signal intensified competition for next‑generation biologics and AI‑driven drug discovery.

Key Takeaways

• Angelini Pharma buys Catalyst for $4.1B, entering rare‑disease neurology market.
• Bayer acquires Perfuse Therapeutics for $2.45B, adds glaucoma candidate PER‑001.
• BMS secures 13 oncology programs from Hengrui in $15.2B licensing pact.
• Pfizer‑Innovent partnership targets up to $9.85B ADC development pipeline.
• Eli Lilly spends $4B on four biotech deals to boost infectious vaccines.

Pulse Analysis

The May M&A wave underscores a strategic pivot toward rare‑disease and ophthalmology platforms, where established players seek to diversify revenue streams beyond traditional small‑molecule drugs. Angelini Pharma’s takeover of Catalyst grants it a U.S. foothold and a pipeline of neuro‑rare therapeutics, while Bayer’s purchase of Perfuse adds a late‑stage glaucoma candidate, PER‑001, to its eye‑care portfolio. These moves reflect a broader industry trend of leveraging high‑margin biologics to offset generic erosion and to capture premium pricing in underserved patient populations.

Licensing activity, though quieter, delivered the sector’s largest single deal: BMS’s $15.2 billion agreement with Hengrui Pharma. By acquiring worldwide rights to 13 early‑stage oncology, hematology and immunology programs—excluding China, Hong Kong and Macau—BMS accelerates its pipeline while Hengrui secures upfront cash and milestone upside. Parallel collaborations in antibody‑drug conjugates illustrate the high‑stakes bet on next‑generation oncology therapeutics; Pfizer’s joint venture with Innovent promises up to $9.85 billion in milestones, and Regeneron’s tie‑up with Parabilis adds a peptide‑antibody hybrid approach to tackle traditionally “undruggable” targets.

Beyond deals, the month highlighted the rising influence of AI, RNA and vaccine technologies. GSK’s $1 billion commitment to siRNA developer SiranBio and Boehringer Ingelheim’s $478 million milestone for an innovative antibody signal confidence in nucleic‑acid and next‑gen antibody modalities. Eli Lilly’s $4 billion multi‑deal spree—spanning shingles, bacterial, EBV and DNA‑nanoparticle platforms—demonstrates a decisive push into infectious‑disease prevention, a segment gaining urgency after the pandemic. Collectively, these transactions suggest a competitive landscape where scale, platform diversity, and advanced technology integration become decisive factors for long‑term growth.