Bimagrumab

An experimental antibody that blocks activin type II receptors, studied for losing fat while keeping or building muscle.

Evidence: Ongoing clinical research
Half-life: Weeks
Sources: 2 cited

Is bimagrumab FDA-approved?

Investigational. Not FDA-approved.

Overview

Bimagrumab blocks signals like myostatin and activin that normally hold back muscle growth. In a 48-week phase 2 trial in adults with type 2 diabetes and obesity, it cut fat mass by about 20% while lean mass rose about 4%. Newer trials pair it with semaglutide to see whether more of the weight lost comes from fat rather than muscle.

How it works

By blocking the receptor that myostatin and activins use, it takes the brakes off muscle growth and shifts the body toward burning fat.

How long does bimagrumab stay in the body?

An antibody that stays in the body for weeks; given by IV infusion in trials.

What it's studied for

Fat loss with muscle preservation
Combination with GLP-1 medicines
Type 2 diabetes

Reported side effects

Muscle spasms, diarrhea, acne (reported in trials)

Sources

The studies and prescribing labels this page is written from.