---
title: "Pfizer's Obesity Drug Shows 16% Weight Loss In Phase 2b Study"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/289090641.md"
description: "Pfizer reported Phase 2b data for its investigational obesity drug berobenatide, showing a 15.9% non-placebo-adjusted weight loss. The company plans to advance multiple Phase 3 studies in 2026 for chronic weight management and related comorbidities. Concurrently, the FDA expanded HYMPAVZI's indication for hemophilia patients. Despite these developments, Pfizer shares declined by approximately 1.3%."
datetime: "2026-06-08T18:06:43.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/289090641.md)
  - [en](https://longbridge.com/en/news/289090641.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/289090641.md)
---

# Pfizer's Obesity Drug Shows 16% Weight Loss In Phase 2b Study

**Pfizer Inc.** (NYSE:PFE) shares are trading lower by almost 1% on Monday as the company shared data from Phase 2b studies of berobenatide, an investigational GLP-1 receptor agonist for weight management.

## Pfizer Berobenatide Update

On Saturday, the company reported that the Phase 2b studies for berobenatide demonstrated a non-placebo-adjusted weight loss of 15.9% in participants.

The pivotal Phase 3 study is currently open for enrollment, which may further bolster Pfizer’s position in the obesity treatment market.

Pfizer plans to advance 10 Phase 3 studies for berobenatide in 2026 for chronic weight management and obesity-related comorbidities, including knee osteoarthritis and obstructive sleep apnea, as part of a broader program of 20+ obesity trials.

The first clinical experience with the top weekly dose for berobenatide is were presented for the first time.

**Read Also: Pfizer Strikes Up To $10.5 Billion Deal With China's Innovent Biologics To Develop Next-Gen Cancer Therapies**

Results from a 32-week exploratory extension (Part B) of the Phase 2b VESPER-1 study showed a non-placebo-adjusted weight loss of 15.9% with no plateau observed at 32 weeks on berobenatide (Week 60 of the overall study), in participants who escalated from placebo to 2.4 mg weekly berobenatide.

## Phase 3 Program Expands

The VESPER-6 pivotal Phase 3 study investigating monthly maintenance dosing for berobenatide in obese adults is open for enrollment, as well as the SOLIS-1 Phase 2b study investigating weekly and monthly maintenance dosing of an ultra-long-acting amylin analog (PF’3945) as a monotherapy and in combination with berobenatide.

## FDA Expands HYMPAVZI Indication

On Monday, the U.S. Food and Drug Administration (FDA) approved an expanded indication for Pfizer’s HYMPAVZI (marstacimab-hncq) to include hemophilia A or B patients 12 years and older with inhibitors and pediatric patients (ages 6 to 11 years) with or without inhibitors.

HYMPAVZI is the first subcutaneous non-factor therapy available for pediatric patients with hemophilia B aged 6 to 11 years.

**PFE Stock Price Activity:** Pfizer shares were down 1.3% at $25.70 at the time of publication on Monday, according to Benzinga Pro data.

**Read Also: Cramer's Lightning Round: Buy Reddit Slowly, Avoid Chasing 'Parabolic' Winners**

_Photo: Molly Woodward / Shutterstock_

### Related Stocks

- [PFE.US](https://longbridge.com/en/quote/PFE.US.md)
- [01801.HK](https://longbridge.com/en/quote/01801.HK.md)
- [RDDT.US](https://longbridge.com/en/quote/RDDT.US.md)

## Related News & Research

- [Pfizer Says FDA Approves Expanded HYMPAVZI Indication For Hemophilia A And B](https://longbridge.com/en/news/289046752.md)
- [BUZZ-Street View: Pfizer's monthly obesity shot awaits key late-stage study results](https://longbridge.com/en/news/289042459.md)
- [Why Ciena stock stumbled today](https://longbridge.com/en/news/289114464.md)
- [Cerity Partners LLC Buys 1,448,806 Shares of Pfizer Inc. $PFE](https://longbridge.com/en/news/289292675.md)
- [Novo Nordisk Says Participants Treated With Zenagamtide Showed Body Weight Loss Up To 14.6% At Week 36 With Highest Dose Investigated, 40 Mg](https://longbridge.com/en/news/288912420.md)