Eli Lilly moved to shut down a growing “black market” for retatrutide, filing the first lawsuits targeting six U.S. sellers. The company alleges the businesses are offering illegal versions of its investigational triple-G weight-loss drug and diabetes candidate, despite the FDA’s ongoing development status. Lilly’s complaints focus on compounding pharmacies, medical spas, and online sellers advertising “research-use only” versions while allegedly providing human dosing instructions. The company said it has reported more than 200 entities engaged in the illegal market to the FDA, DOJ, state attorneys general, and law enforcement. The enforcement push underscores the regulatory sensitivity around highly anticipated metabolic medicines and adds pressure to compliance systems across pharmacies and distribution channels.