Novo Nordisk asked the Food and Drug Administration to prevent compounding pharmacies from making cheaper versions of its popular weight loss injection Wegovy and diabetes treatment Ozempic. The Danish drugmaker contends the medications are too complex for those manufacturers to make safely.

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 has asked the FDA to block production of compounded copies of Ozempic, arguing that it’s too difficult to do safely. It’s the latest escalation in a brewing war between pharmaceutical companies and compounders.

Novo Nordisk on Tuesday asked the U.S. Food and Drug Administration to ban compounding pharmacies from making copycat versions of its popular weight-loss and diabetes drugs, which it said were too complex for those manufacturers to produce safely.

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,

Under US law, compounding pharmacies can make and sell patent-protected drugs that are on the FDA's shortages list in limited amounts, and have been reaping the rewards of supplying versions of Novo Nordisk's obesity drug Wegovy and Ozempic for diabetes, which are both based on the GLP-1 receptor agonist.

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