Lilly files six lawsuits against US retatrutide sellers

On 12 August 2026, Eli Lilly and Company announced that it had filed six lawsuits in US federal courts against businesses it says sell unapproved versions of retatrutide, its investigational GIP, GLP-1 and glucagon receptor agonist ¹. Lilly described the defendants as including compounding pharmacies, medical spas and online sellers, and said some of them falsely present their products as "research-use only" ¹.

The cases

Lilly's announcement lists the following cases ¹:

• Eli Lilly & Co. v. Aesthetic Envy Cosmetic Centers LLC, d/b/a Aesthetic Envy (N.D. Cal.)
• Eli Lilly & Co. v. Astra LLC, d/b/a Astra Peptides (W.D. Tex.)
• Eli Lilly & Co. v. Legendary Peptides, LLC (E.D. Tex.)
• Eli Lilly & Co. v. Striker Pharmacy, LLC (S.D. Tex.)
• Eli Lilly & Co. v. Texas Peptides Inc. (W.D. Tex.)
• Eli Lilly & Co. v. Lone Star Peptide Co. (S.D. Tex.)

The announcement does not set out the specific legal claims; those are in the complaints themselves ¹. The filings are allegations by Lilly. None of them has been decided, and the defendants have the opportunity to respond in court.

What else Lilly reported

Alongside the lawsuits, Lilly said it had referred more than 200 individuals and entities to FDA, the US Department of Justice, state attorneys general, law enforcement and professional licensing boards, and had reported more than 14,000 websites, advertisements, social media posts and product listings marketing retatrutide in more than 100 countries ¹. The company called on online platforms, payment companies, shipping carriers and regulators to act against the trade ¹.

Lilly's chief medical officer, David A. Hyman, M.D., said in the release: "What is being sold on the black market is not a medicine – it is entirely unverified, unapproved and not worth the risk" ¹. The release also states that no medicine containing retatrutide has been approved for human use by any regulatory agency in the world ¹.

Regulatory background

FDA's page on unapproved GLP-1 drugs, last updated 1 October 2026, states that retatrutide cannot be used in compounding under federal law and that it is not a component of an FDA-approved drug ². The same page says FDA has warned companies that sold unapproved drugs containing retatrutide and other incretin compounds labelled "for research purposes" or "not for human consumption", and that these products were sold directly to consumers for human use with dosing instructions ². Trade coverage noted that Lilly has used litigation before, including 2023 suits against companies making or selling compounded versions of its tirzepatide product ³.

On the development side, Lilly reported phase 3 results for retatrutide in 2026 and said it plans to submit a Biologics License Application to FDA in the first quarter of 2027 ⁴. Until FDA or another regulator reviews and approves an application, retatrutide remains an investigational drug available legitimately only within registered clinical trials.

What this means for readers

• The lawsuits are about who may lawfully sell retatrutide, not about new scientific data on the molecule.
• A "research use only" label is not treated by FDA, or by Lilly in these complaints, as settling how a product is actually marketed or used ^1,2. Amiravo's guide to what research use only means covers that background.
• Retatrutide's published human data come from Lilly-sponsored clinical trials; material sold outside those trials has no regulatory review of identity, purity or content. The retatrutide entry summarizes the trial literature.
• These cases may take months or years to resolve. Amiravo will note outcomes when courts publish them.