Pfizer obesity drug delivers 18% weight loss in late-stage trial

Pfizer said its experimental obesity treatment produced an average weight loss of 18% after 68 weeks in a late-stage clinical trial, a result that puts the company closer to joining a fast-growing market for anti-obesity medicines.

The once-weekly injection was tested against semaglutide in a head-to-head study, where it showed stronger results on average. The company has been working to build a pipeline in obesity care after other drugmakers have already seen major commercial gains from similar treatments.

The findings are based on trial data and still need to be reviewed in the context of safety, durability, and real-world use. As with any late-stage result, the next steps will determine whether the drug can move toward regulatory filing and eventual approval.

Interest in obesity medicines has surged as patients and doctors look for treatments that can produce significant weight loss with manageable side effects. Pfizer’s data suggests it may have a credible contender, but broader evidence will be needed before the drug can be judged against existing options.