What is Brenipatide? An Analysis of LY3537031

Note: this article will be updated when new information is available.

It’s only been about a month since Brenipatide was christened with its nonproprietary name: before then, it was known as LY3537031. Not a whole lot is known about it, but over the past few days, Lilly has submitted a few trial details that are interesting.

First and foremost: it isn’t designed to be a rival to retatrutide. It is a peptide, and it’s even a GIP/GLP-1 dual RA (meaning weight loss is a potential outcome), but the study details we have are steering the investigation toward alcohol use disorder (AUD) and semi-surprisingly, asthma. Asthma is a chronic lung disease driven mainly by inflammation, which GLP-1 RAs can reduce independently of weight loss. Out of curiosity, I did a brief background check on asthma and potential links to AUD – there doesn’t appear to be a mechanistic link and longitudinal studies don’t find much of interest.

Lilly has one phase 1 study currently underway specifically looking at Brenipatide in overweight and obese individuals (NCT06606106), but the two phase 3s that were posted in October 2025 to ClinicalTrials.gov are very similar and both pertain to AUD (NCT07219966 and NCT07219953). Phase 3 trials aren’t cheap, so Lilly clearly sees something in Brenipatide and just a few days ago, it added a phase 2 trial to evaluate the peptide for asthma (NCT07219173), though previous phase 1s have shown a definite skew toward its impact on the liver and I suspect that long-term, Lilly is looking at a specific use case where it can treat alcoholics and problem drinkers with a once-weekly injectable.

Alcohol is quite literally a poison and several cancers have causal links to its usage. I don’t think it’s quite as destructive on society as obesity currently is, but as an Australian, I’ve seen the impact AUD has on indigenous communities firsthand. Current interventions are costly and quite low yield: I hope that Brenipatide is successful through its trials and becomes a first line treatment for AUD. Indigenous Australians are disadvantaged and alcohol use is the second largest contributor to their total disease burden (second only to heart disease), which means there’s a high ROI on AUD interventions. The federal government should see this as a potential opportunity to make a generational shift in Australia’s alcohol consumption rates, which are quite high when compared to other countries.

We have to be careful with anecdotes and N=1, but when enough people taking GLP-1 RAs mention a reduction in alcohol consumption, it’s something to pay attention to. Additionally, there have been a few studies that look into it directly. One small randomized clinical trial (Once-Weekly Semaglutide in Adults With AUD) published its data back in February 2025 and it looked promising: there’s also this observational study that provides us with some useful data. The real question is whether Brenipatide is better than the other GLP-1s for AUD (and potentially asthma). Pharmaceutical companies have a track record of doing interesting things for various profit-maximizing reasons, and as much as I’d like to cover that topic – I’ll just cross my fingers that out of all available GLP-1 RAs, Brenipatide is the most efficacious medicine for the trials it’s being administered in.

We’re a long way away from knowing if Brenipatide is any good, and I don’t expect much coverage on it for at least a year or two, but if Lilly can continue to produce high-quality agonists, perhaps there’s a suite of peptide-based medications waiting to be discovered.