Pfizer and Amgen Report Midstage Data on Experimental Monthly GLP-1 Drugs for Weight Loss

Pfizer presented results from the first 28 weeks of its ongoing middle-stage trial of berobenatide at the American Diabetes Association’s annual conference on Saturday. 3% of their body weight on average. A separate midstage trial found berobenatide helped patients with Type 2 diabetes manage blood sugar levels.

Pfizer’s experimental drug berobenatide stays attached longer to albumin in the blood, which protects the molecule from being broken down too quickly. Participants began with lower doses that were gradually increased over the first few weeks. They started on weekly injections for 12 weeks before moving to monthly shots.

The weight-loss trial is set to run for 64 weeks. Dr. John Buse, an endocrinologist at the University of North Carolina School of Medicine who worked on the trial, said side effects were mainly gastrointestinal symptoms and were similar to or not as bad as those seen with other GLP-1 drugs.

Issues were more common when patients first transitioned from weekly to monthly dosing. Buse said berobenatide binds to the GLP-1 receptor in a way that minimizes side effects. “The GLP-1 receptor where the GLP-1 docks, it has got two signaling paths that it works through.

And this one [berobenatide] is driving one of those two, whereas normally when you have a GLP-1 molecule, it drives both at the same time,” Buse said. Amgen’s monthly GLP-1 drug, called MariTide, is currently being tested in late-stage trials. The drug uses an antibody to prolong its stay in the body and blocks the GIP receptor.

Amgen is testing whether MariTide could be taken every other month or every three months and whether it can treat obesity-related problems such as heart disease and sleep apnea.