Lilly details the scale of its retatrutide enforcement campaign

Eli Lilly has laid out the scope of its campaign against the underground market for retatrutide, its experimental three-hormone obesity injection. The company says it has referred more than 200 people and entities to the U.S. Food and Drug Administration, the Department of Justice, state attorneys general and law enforcement, and has reported more than 14,000 websites, advertisements, social media posts and product listings marketing retatrutide across more than 100 countries ^[1][2].

The enforcement push follows six lawsuits Lilly filed on Aug. 12 ^[2]. The complaints target suburban Houston-based compounding pharmacy Striker Pharmacy; Sacramento, California-based medical spa chain Aesthetic Envy; and online Texas sellers Astra Peptides of Austin, Texas Peptides and Lone Star Peptide Co. of Houston, and Legendary Peptides of Lumberton ^[2]. Lilly used a similar strategy last year when it sued two compounding pharmacies and four telehealth companies over compounded tirzepatide, the active ingredient in Zepbound and Mounjaro ^[2].

What the lawsuits say

Many of the sellers label their products "for research use only," but Lilly argues that framing is a pretext. The Lone Star complaint points to a "Retatrutide Dosage Calculator" on the seller's website that instructs users to "Enter the vial strength, the bacteriostatic water you added, and your target dose" ^[2]. The complaint states that the substance "is not a chemical intended for research use but instead a drug it intends and sells for human use," and that "Retatrutide cannot legally be sold for human use to anyone, anywhere, for any reason" ^[2].

Legendary Peptides declined to comment on the lawsuit, four of the other businesses did not respond to requests for comment, and an email to Astra was returned as undeliverable ^[2].

Lilly Chief Medical Officer Dr. David Hyman said in the announcement of the lawsuits that what is sold on the black market "is not a medicine — it is entirely unverified, unapproved and not worth the risk" ^[2]. Spokesperson Jared Shapiro said platforms are "not doing enough to block this content" ^[2].

The drug itself is not approved

Retatrutide is a once-weekly injectable designed to act on three receptors — GLP-1, GIP and glucagon ^[2]. Zepbound targets GLP-1 and GIP, Wegovy targets GLP-1, and Lilly's once-daily pill Foundayo (orforglipron) targets GLP-1 ^[2]. Retatrutide is still in Phase 3 testing, and Lilly plans to file for approval in the first quarter of 2027 ^[2].

Phase 3 results released in May, in a study of 2,339 patients, showed people on 12 milligrams lost an average of 70.3 pounds, or 28% of body weight, after 80 weeks, with nearly half of that group losing an average of 30% ^[2]. The 4-milligram group lost an average of 47.2 pounds and the 9-milligram group 64.4 pounds ^[2]. In an extension study, participants with a body mass index of 35 or higher lost an average of 85 pounds, or 30.3% of body weight, at 104 weeks ^[2]. Lilly reported that 11% of trial participants stopped the drug because they felt they were losing too much weight, and that about 11% taking the highest dose discontinued because of side effects, most commonly nausea, diarrhea, vomiting and constipation ^[2]. By comparison, Wegovy and Zepbound patients can lose up to about 20% of body weight ^[2].

Why it matters for patients

There is no legal, approved retatrutide product in the United States, so anything sold online or at a med spa today falls outside the system that checks what is in a vial and how much ^[2]. Reported harms are accumulating: the Washington Poison Center has logged a growing number of calls about illegal retatrutide, Australian health authorities reported six cases of liver toxicity this summer among people using the unapproved drug, and Lilly says patients have reported serious harms including hospitalizations ^[2]. An August pre-print by three Boston-area researchers found black-market retatrutide use was associated with lower weight loss and more cardiovascular symptoms ^[2].

Lilly argues in its complaints that by launch, sellers "will have already conditioned the public to associate retatrutide as an ingredient with danger, illegality, and reduced or total lack of efficacy," forcing the company into "rehabilitating a product that has been tarnished" ^[2].

What happens next

The six lawsuits filed Aug. 12 are pending ^[2]. Lilly's regulatory filing is planned for the first quarter of 2027, meaning an approval decision, label and pricing are not yet known ^[2]. Whether the FDA, DOJ or state attorneys general act on Lilly's 200-plus referrals has not been reported ^[2].