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Novo Nordisk has started a website to offer information on how to distinguish FDA-approved products from other versions.
CNN  — 

Pharmaceutical firm Novo Nordisk says it has begun legal proceedings against some US medical spas, weight loss or wellness clinics and compounding pharmacies “to cease and desist from false advertising, trademark infringement and/or unlawful sales of non-FDA approved compounded products claiming to contain semaglutide,” the active ingredient in its diabetes and weight-loss medications Ozempic, Wegovy and Rybelsus.

“These unlawful marketing and sales practices … have created a high risk of consumer confusion and deception as well as potential safety concerns,” Novo Nordisk said in a news release Tuesday. It did not offer any further details on the targeted companies or their practices.

The US Food and Drug Administration issued a warning last month about some compounded versions of semaglutide.

Compounding “is the process of combining, mixing, or altering ingredients to create a medication tailored to the needs of an individual patient,” the agency said. “Compounding includes the combining of two or more drugs.”

Semaglutide, a type of drug called a GLP-1 agonist, is FDA-approved as Ozempic and Rybelsus to treat type 2 diabetes and as Wegovy to treat overweight and obesity.

The FDA said that it has received reports of adverse events in people who used compounded semaglutide and that patients “should not use a compounded drug if an approved drug is available.”

Ozempic and Wegovy have been on the FDA’s Drug Shortages list since last year.

“When a drug is in shortage, compounders may be able to prepare a compounded version of that drug if they meet certain requirements of the Federal Food, Drug, and Cosmetic (FD&C) Act,” the FDA said, but the agency doesn’t review these compounded versions for safety, effectiveness or quality.

Some compounders may also be using salt forms of the medication, such as semaglutide sodium and semaglutide acetate, which have different active ingredients from those in the approved drugs. “The agency is not aware of any basis for compounding using the salt forms that would meet the FD&C requirements. … Products containing these salts, such as semaglutide sodium and semaglutide acetate, have not been shown to be safe and effective.”

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Novo Nordisk said in its release that people who have a prescription for semaglutide “should be vigilant in checking their medicine to ensure they are taking an authentic” version. Its new website offers more information on how to distinguish FDA-approved products from “counterfeit” ones.

In a statement to CNN on Wednesday, the company said its “legal actions are focused on preventing entities in the marketplace from engaging in misleading or false advertising, infringing our trademarks, or illegal distributing compounded products claiming to contain semaglutide.

“We will continue to evaluate any and all appropriate actions against entities that violate Novo Nordisk’s intellectual property rights in connection with their sale of compounded drug products purporting to contain semaglutide,” Novo Nordisk wrote.

On an earnings call earlier Tuesday, Novo Nordisk said it’s been ramping up production capacity of Wegovy, as it’s had trouble keeping up with demand, last month limiting doses for new patients in the US to be able to meet the needs of people already taking the medicine.

The company also plans to study whether it’s possible for patients to maintain their weight loss after stopping the medication but expects it to be a chronic therapy for the foreseeable future.

“Based on the knowledge we have today, we’re talking about a chronic treatment in order to maintain weight loss,” Dr. Martin Holst Lange, executive vice president of development at Novo Nordisk, said in a briefing Tuesday. He noted that the company has shown that patients can maintain weight loss of about 15% over two years while staying on Wegovy but that those who stop the drug regain weight.

CNN’s Meg Tirrell contributed to this report.