Pfizer and Blackstone Life Sciences have entered a strategic co-funding agreement to advance berobenatide, an investigational monthly GLP-1 receptor agonist peptide for chronic weight management and obesity-related conditions. Under the deal, Blackstone-managed funds will contribute up to $1.5 billion toward development costs through 2028. In return, Blackstone is eligible for milestone payments contingent on U.S. regulatory approval of the injectable monotherapy and future commercial sales targets.

“Our aim is to bring important new medicines to patients while taking a disciplined approach that pairs internal research investments with targeted investment from capital partners. Today’s announcement helps us advance our comprehensive obesity program and maintain the financial capacity and flexibility to invest in our broader pipeline across all therapeutic areas,”  Cecile Guegan, Chief Financial Officer and Executive Vice President, Pfizer.

"We are pleased to further expand our relationship with Pfizer and support the broad and rigorous development of berobenatide as the anchor of Pfizer’s cardiometabolic pipeline. This collaboration is a good example of our leadership in providing capital solutions at scale to advance important medicines and technologies to patients," said Dr. Nicholas Galakatos, Global Head of Blackstone Life Sciences.

Any earned milestone payments will be distributed to Blackstone across multiple years. Under the agreement, Blackstone receives no ownership or rights to berobenatide, leaving Pfizer with complete operational control and decision-making authority over the drug program. Additionally, Blackstone Life Sciences will co-invest alongside funds from Blackstone's perpetual private equity strategy (BXPE).

Pfizer is advancing over 20 obesity-related clinical trials in 2026, anchored by 10 Phase 3 studies for berobenatide (PF’3944). As a potential first-in-class monthly GLP-1 peptide, berobenatide is being evaluated for chronic weight management, knee osteoarthritis, and obstructive sleep apnea. Supported by growing clinical evidence, Pfizer is developing the drug both as a standalone treatment and in combination with amylin analogs and other nutrient-stimulated hormone (NuSH) peptides.