Pfizer's Berobenatide Delivers 15.9% Weight Loss, Advances 10 Phase 3 Trials
PFE•Pfizer's experimental GLP-1 agonist berobenatide achieved up to 15.9% body weight reduction over eight months at highest weekly dose in Phase 2b VESPER-1, and nearly 15% loss after 14 months with monthly dosing in VESPER-3. The company plans over 20 obesity trials in 2026, including 10 Phase 3 studies.
1. Phase 2b VESPER-1 Results
In the Phase 2b VESPER-1 trial, patients receiving the highest weekly dose of berobenatide achieved a mean 15.9% reduction in body weight over eight months, with no weight-loss plateau observed. Tolerability remained favorable as participants escalated to the top dose.
2. VESPER-3 Monthly Dosing Findings
VESPER-3 data showed patients on the highest four-week dosing regimen lost nearly 15% of body weight after 14 months. The results highlight berobenatide’s potential as the first once-a-month GLP-1 therapy, offering greater convenience over weekly alternatives.
3. Expanded Clinical Program
Pfizer is advancing more than 20 trials across obesity and related metabolic conditions in 2026, including ten active or planned Phase 3 studies. Upcoming studies will assess impacts on comorbidities such as sleep apnea and knee osteoarthritis and will expand into China and Japan.
4. Commercial and Future Outlook
Following its $10 billion Metsera acquisition, Pfizer leverages its commercial network to support primary-care adoption of obesity treatments. Company executives project that berobenatide’s tolerability and monthly dosing could drive sustained patient adherence in real-world settings.
