Eli Lilly is stepping up its fight against copycat weight loss drugs

In its continuing war against copycat drugs, Eli Lilly (LLY) said on Wednesday that it filed suits against four telehealth companies that offer cheaper versions of its blockbuster GLP-1 weight loss drugs Mounjaro and Zepbound.

The lawsuits, against Mochi Health, Fella & Delilah Health, Willow Health, and Henry, come just weeks after Lilly filed two lawsuits against compounding pharmacies Empower Pharmacy and Strive Pharmacy, alleging that they make and sell unauthorized versions of tirzepatide, the active ingredient in both Mounjaro and Zepbound.

Those two drugs accounted for over $16.4 billion in revenue for the company last year. In the new lawsuits, Lilly alleges that the four companies are selling illegal knockoffs of its drugs, in some cases adding untested ingredients like vitamins and amino acids to distinguish them from patented weight-loss drugs.

Lilly also claims that some of the formulations haven’t been studied, such as oral tablets and drops, “putting patients at risk by engaging in dangerous, deceptive, and unlawful practices.”

When Mounjaro went into short supply in late 2022, the Food and Drug Administration allowed pharmacies and outsourcing facilities to produce tirzepatide through a practice called compounding. But compounding was supposed to stop in March when the FDA declared that the shortage was over.

Some compounders continued to sell the reconfigured drugs, however, labelling their products as personalized versions that differ slightly from the brand name drugs. Mochi Health, for one, has been upfront about its plans to continue selling compounded versions of tirzepatide.

In March, Mochi CEO Myra Ahmad told CNBC that she wasn’t worried about legal action because with compounding, doctors “get full autonomy to decide what is the best way to manage their patients” by creating personalized formulations.

In its filing Wednesday, Lilly claimed that Mochi and its owners “exercise undue influence and control over, among other things, the prescribing decisions of physicians.”

In all four cases, Lilly is seeking to stop the companies from marketing or selling tirzepatide.