Eli Lilly is currently developing retatrutide, a peptide that early clinical trials suggest could be particularly effective for weight loss. Following favorable initial results, the laboratory plans to file for marketing approval with the Food and Drug Administration (FDA) in the first quarter of 2027. However, the molecule is already being sold clandestinely on social media, giving rise to numerous abuses, according to BFM Business.
A Triple-Receptor Approach
Retatrutide, nicknamed “King Kong” by some physicians, would be the first drug to target three receptors, mimicking three natural intestinal and pancreatic hormones: GLP-1, GIP, and glucagon. Eli Lilly’s Mounjaro targets only two (GLP-1 and GIP), while Novo Nordisk’s Wegovy targets just one (GLP-1). According to the latest trials published in May, retatrutide could enable weight loss of 28.3% over 18 months at the highest dose, while limiting the loss of lean muscle mass.
A Booming Black Market
These claims have generated significant enthusiasm around retatrutide, particularly against the broader backdrop of a shortage of weight-loss treatments in the United States since 2023. A veritable black market has organized, with Chinese research laboratories illegally marketing their drugs through influencers on social media.
In the United States, several fitness influencers with more than 200,000 followers tout the benefits of peptides and direct users to websites selling retatrutide at prices ranging from $80 to $350. In France, accounts presenting themselves as “pharmacists” also highlight links supposedly allowing the purchase of the molecule. TikTok attempted to act against this illegal trade in 2025 by removing content linked to certain keywords such as “retatrutide” or “reta.” But users have found ways around these restrictions.
Proven Dangers
However, numerous risks surround these illegal sales. Fraudulent injectable “peptides” present a higher risk of side effects, including liver damage, infections, or severe allergic reactions, according to the French National Agency for the Safety of Medicines and Health Products (ANSM). More generally, products sold clandestinely under the name retatrutide, particularly those from China, present uncertainties regarding their composition, dosage, and actual efficacy.
The situation echoes growing concerns about the diversion of anti-obesity medications, as pharmacovigilance authorities continue to monitor the misuse of these treatments. In France, two anti-obesity drugs are now reimbursed, but access remains tightly controlled.
As Eli Lilly prepares its regulatory submission, the gap between legitimate clinical development and the unregulated online marketplace continues to widen, leaving health authorities grappling with how to protect consumers from potentially dangerous counterfeit products.
