Pfizer Secures Up to $1.5 Billion From Blackstone for Obesity Drug

Pfizer has entered into a strategic funding agreement with Blackstone Life Sciences to support the development of its experimental obesity treatment, berobenatide.

Under the agreement, Blackstone will provide up to $1.5 billion to help cover development costs for berobenatide through 2028. The drug is being developed as a potential once-monthly GLP-1 receptor agonist for chronic weight management and obesity-related health conditions.

The funding will help Pfizer move its obesity research programme forward while maintaining the company’s ability to invest in other areas of its drug pipeline.

Funding to Support Clinical Development

Berobenatide, also known as PF’3944, is an investigational peptide designed to target the GLP-1 receptor. Pfizer is studying it as a potential monthly injectable treatment for people living with obesity and related conditions.

As part of the agreement, Blackstone will be eligible to receive milestone-based payments. These payments will depend on US regulatory approval of monthly injectable berobenatide as a standalone treatment for chronic weight management, as well as the achievement of certain commercial sales targets.

The companies have not disclosed the potential value of these milestone payments. Any payments earned will be made to Blackstone over several years.

Importantly, Blackstone will not receive ownership or development rights to berobenatide. Pfizer will retain full operational control and responsibility for decisions related to the drug’s development.

Pfizer Expands Its Obesity Drug Pipeline

Pfizer plans to advance more than 20 clinical trials focused on obesity and related health conditions in 2026. This includes 10 ongoing or planned Phase 3 trials involving berobenatide.

The company is exploring the drug both as a standalone treatment and in combination with other peptide-based medicines, including amylin analogues. Its development programme also covers obesity-related conditions such as knee osteoarthritis and obstructive sleep apnoea.

The funding agreement comes as pharmaceutical companies continue to invest heavily in treatments for obesity, a market that has grown rapidly with increasing interest in GLP-1-based medicines.

For Pfizer, the partnership provides additional financial support for the development of berobenatide without giving up control of the programme. It also allows the company to direct resources towards other research and development projects.

The agreement builds on an earlier collaboration between Pfizer and Blackstone, which involved funding support for the development of certain Pfizer medicines.

Berobenatide remains an investigational drug, and its safety and effectiveness for chronic weight management will need to be established through clinical trials and regulatory review.