By Patrick Wingrove

Eli Lilly on Tuesday said it was suing 10 U.S. medical spas, wellness centers and compounding pharmacies for selling products claiming to contain tirzepatide, the active ingredient in its diabetes drug Mounjaro which is expected to be approved for weight loss later this year.

In four separate lawsuits filed in Florida and Texas federal courts, Eli Lilly is seeking orders barring Better Life Pharmacy, ReviveRX, Rx Compound Store and Wells Pharmacy Network from selling tirzepatide, and requesting unspecified damages.

The Indianapolis-based drugmaker is accusing the four compounding pharmacies, which make customized drug preparations for customers, of violating federal and state consumer protection and competition laws by selling unregulated versions of Mounjaro.

Lilly is the only company with U.S. Food and Drug Administration approval to sell tirzepatide drugs.

The drugmaker is seeking similar injunctive orders and damages against six medical spas and wellness centers from federal courts in Arizona, Florida, Georgia, Minnesota, South Carolina and Utah, accusing them of infringing its trademark by advertising compounded tirzepatide as Mounjaro.

"Defendants use Lilly’s trademark to attract customers and generate revenues and profits, including by passing off as 'Mounjaro' their own unapproved compounded drugs purporting to contain tirzepatide, and doing so for a use for which Mounjaro is not approved, namely weight loss," Eli Lilly said in the lawsuits.

The suits come just over two months after rival Novo Nordisk, which markets the popular obesity treatment Wegovy, sued several medical spas and three compounding pharmacies for selling products claiming to contain semaglutide, the main ingredient in Wegovy and the related diabetes drugs Ozempic and Rybelsus.

Lilly in a statement said, “products claiming to contain tirzepatide that are made and/or distributed by compounding pharmacies or distributed by counterfeit sources have not been reviewed by the U.S. FDA or global regulatory agencies for safety, quality, or efficacy.”

In May, the FDA warned about the safety risks of using compounded or custom-made versions of popular weight-loss drugs such as Wegovy and Ozempic, saying it had received reports of adverse events after patients used compounded versions of semaglutide.

However, the agency has said that depending on circumstances, compounded drugs can be made and distributed with fewer restrictions when the original drug appears on its drug shortages list, which Mounjaro currently does.

Analysts and industry executives have said annual sales of weight-loss treatments like Wegovy and Mounjaro, once it is approved to treat obesity, could hit $100 billion within a decade, and that Lilly’s product could eventually account for more than half of those sales.

(Reporting by Patrick Wingrove; Editing by Bill Berkrot)