Blackstone to Fund Up to $1.5B of Pfizer's Obesity Shot Development
Pfizer has signed a deal with Blackstone Life Sciences that will cover up to $1.5 billion of development costs for berobenatide, an experimental monthly obesity shot. Pfizer announced the agreement on November 11, 2026, from New York and Cambridge, Massachusetts.
What happened
Under the deal, funds managed by Blackstone will pay up to $1.5 billion of berobenatide's development costs through 2028. Pfizer calls it a co-funding agreement.
In return, Blackstone can earn milestone payments. Pfizer said those payments depend on two things:
- U.S. approval of monthly dosing of injectable berobenatide on its own for chronic weight management.
- The drug reaching certain sales milestones.
Pfizer said any milestone payments would be paid to Blackstone over several years. The dollar amounts of the milestones were not disclosed. Pfizer said Blackstone gets no rights or ownership in the drug, and Pfizer keeps full control of the program.
Berobenatide, also known as PF'3944, is a GLP-1 receptor agonist peptide. Pfizer describes it as a potential first-in-class monthly treatment. It is being tested for chronic weight management and for conditions linked to obesity, including knee osteoarthritis and obstructive sleep apnea. Pfizer is developing it as a monotherapy and in combination with other hormone peptides, such as amylin analogs.
Pfizer said there are 10 ongoing and planned Phase 3 trials for berobenatide. It plans to advance more than 20 trials in obesity and related conditions in 2026.
Why it matters
The deal moves part of berobenatide's development bill to an outside investor. Pfizer keeps ownership and control of the drug.
According to BioSpace, Pfizer gained berobenatide through its purchase of Metsera last year, a $10 billion deal. That deal followed a bidding contest with Novo Nordisk.
Analysts at BMO Capital Markets, quoted by BioSpace, said the structure offsets near-term development spending without giving up the asset. Leerink Partners expects the deal to help Pfizer over the next two years. BioSpace reported that the patent cliff for Pfizer's Eliquis begins in April 2028.
Blackstone has struck a similar arrangement before. BioSpace reported that in 2025 Blackstone offered Merck $700 million to cover development costs for its drug sac-TMT, in exchange for royalties on sales.
What it means for people in the industry
Neither Pfizer nor BioSpace said anything about new jobs or sites tied to the deal. The money goes to development work on a program with 10 ongoing and planned Phase 3 trials.
Watch for berobenatide trial results and for a U.S. decision on monthly dosing. Under the deal, U.S. approval of monthly dosing is a condition for Blackstone's milestone payments.
See open pharma jobs in the US and Canada
Sources
Check Your Supplement Interactions
Use our AI-powered checker to analyze supplement safety and interactions.
Open Interaction Checker →Comments (0)
This article is for informational purposes only and does not constitute medical or investment advice. It was written with AI assistance from the sources listed above. Check the original sources before relying on any detail.