The next game-changing weight loss drug just moved closer to FDA approval

• Tirzepatide, a new medication designed for diabetes, continues to show promise in weight loss trials. 
• Recent data found people taking the drug lost nearly 16% of their body weight in 16 months. 
• Manufacturer Eli Lilly expects an update on FDA approval in late 2023. 

A potentially game-changing medication called tirzepatide is moving closer to earning FDA approval for weight loss, with new preliminary data from a clinical trial showing it helped people lose nearly 16% of their body weight in 16 months. 

The drug, manufactured by pharmaceutical company Eli Lilly and sold under the brand name Mounjaro, was originally designed to treat diabetes. It attracted attention for dramatic weight loss results, with an earlier trial published in June 2022, showing participants lost 20% of their body weight, an average of 52 pounds, in about 16 months with once-weekly injections of the drug. 

In the latest study of 938 adult participants with obesity or overweight and type 2 diabetes, those taking tirzepatide lost an average of about 34 pounds, from an average starting weight of around 222 pounds. Those results are significant — participants on a placebo lost just 7 pounds or 3% of their body weight in the same period. 

In addition, around 86% of participants on the medication saw at least 5% weight loss in the study.

The results of the latest study will be presented at American Diabetes Association's 83rd Scientific Sessions and submitted to a peer-reviewed journal.

Tirzepatide is also being submitted for FDA approval as a weight loss medication, and Eli Lilly expects an update to the process in late 2023, according to a press release.

In the meantime, patients can still access the drug — since it has been FDA-approved for diabetes, doctors are able to prescribe it to patients, even for a different purpose, if they think it will help.

A similar medication, semaglutide, was FDA-approved for weight loss in 2021. Its continued popularity has caused shortages and prompted a wave of generic versions of the drug called compounded semaglutide (which are not FDA approved). 

Tirzepatide works similarly to semaglutide, acting on a hormone called GLP-1 that controls appetite, but also affects another insulin-related hormone. Some evidence suggests it could be more effective than semaglutide, although the available data comparing the two was conducted only on patients with diabetes, and did not use the highest dose of semaglutide. 

Side effects of both medications are well-documented but typically mild. About one in five patients reported nausea or diarrhea, and about one in 10 reported vomiting or constipation, according to the latest study of tirzepatide. 

Also like semaglutide, patients need to continue taking tirzepatide in order to maintain the weight loss results.