Ozempic and Wegovy, the two brand names under which the company sells the GLP-1 drug semaglutide, are already blockbusters.

Novo Nordisk wants the Food and Drug Administration (FDA) to prevent compounding pharmacies from manufacturing their own versions of the company’s popular weight loss drug Wegovy and diabetes treatment Ozempic,

Ozempic maker Novo Nordisk (NVO) is asking the U.S. Food and Drug Administration (FDA) to prohibit compounding pharmacies from making off-brand versions of semaglutide, the active ingredient in its blockbuster weight loss and diabetes medications.

Novo Nordisk is pushing the FDA to block compounders from making copies of its Ozempic and Wegovy, saying the weight-loss treatments are too complex to safely replicate. Why it matters: It's the latest twist in the battle between pharma giants and compounders over the law that allows copies of patent-protected drugs amid shortages.

The Danish drugmaker Novo Nordisk contends that semaglutide, the active ingredient in Ozempic and Wegovy, is too complex for those manufacturers to make safely.

The agency posted documents this week that the drugmaker had requested the drug be placed on the FDA's "Demonstrable Difficulties for Compounding Lists."