Pfizer Advances Early-Stage Obesity Asset With New Gastric Emptying Study

Pfizer Inc (PFE) announced an update on their ongoing clinical study.

Pfizer Inc. (PFE) is running a Phase 1 study called “A PHASE 1, OPEN-LABEL, MULTIPLE DOSE STUDY TO INVESTIGATE THE IMPACT OF PF 08653944 ON GASTRIC EMPTYING IN ADULT PARTICIPANTS WITH OVERWEIGHT OR OBESITY.” The goal is to see how the drug PF-08653944 affects how fast food leaves the stomach and to check its safety, which could guide future obesity trials.

The main treatment is PF-08653944, a shot given under the skin and aimed at weight-related pathways by slowing how quickly the stomach empties. Acetaminophen, taken by mouth, is used as a tool drug to track stomach emptying speed, because its absorption changes as the stomach empties.

This is an interventional, early-stage study with no random assignment between different treatment arms, and it uses several treatment periods run in parallel. The trial is open-label, so both doctors and participants know what is given, and the main goal is basic research on how the drug behaves in the body rather than direct weight-loss outcomes.

The study started after initial submission on 27 March 2026, marking the formal launch of recruitment and dosing in healthy adults with overweight or obesity. The latest update was filed on 20 April 2026, which signals active trial management; primary and final completion dates are not yet reported, so investors should assume data readouts are still at least several quarters away.

For investors, this update supports Pfizer’s push into obesity and metabolic health, an area led today by GLP-1 players like Eli Lilly and Novo Nordisk. While this is only a Phase 1 mechanistic study and not a near-term revenue driver, it adds optionality to PFE’s pipeline and, if safety and gastric effects look favorable, could modestly improve sentiment around Pfizer’s long-term growth story.

The study remains ongoing and updated, with more details available on the ClinicalTrials.gov portal under the listed NCT identifier.

To learn more about PFE’s potential, visit the Pfizer Inc drug pipeline page.