The drug is called bimagrumab.
It was originally developed for rare muscle-wasting diseases, but in a trial involving people with obesity and type 2 diabetes, researchers noticed something unexpected.
Participants who received the drug:
đź”· Lost 20% of their body fat
đź”· Gained lean muscle mass
đź”· Improved insulin sensitivity
đź”· And did all this without changes to diet or exercise
This matters because most weight loss treatments, including GLP-1 medications, cause people to lose both fat and muscle.
That’s not ideal. Muscle is metabolically active and plays a key role in long-term health.
Bimagrumab works differently. It blocks proteins like myostatin and activin A that normally limit muscle growth. By removing those brakes, it allows the body to add muscle even as it burns fat. Any personal trainer will tell you this is incredibly difficult unless you’re a brand new trainee.
Lilly sees the opportunity.
A drug like this could help preserve strength and metabolic function during weight loss, especially in older adults or those already losing muscle.
We often talk about “body weight,” but the more important metric is what that weight is made of. How much is fat. How much is muscle. That’s body composition. And changing it in the right direction could have far-reaching effects on health and longevity.
The science is still developing.
But $2 billion says this isn’t just a side story. It’s the next chapter.
Source: LinkedIn – Derek Berkey
