The hugely popular weight-loss drugs including Ozempic may cause suicidal thoughts. Europe is investigating

Woman with cereal
Weight loss drugs may have serious side effects.
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Novo Nordisk A/S’s weight-loss medications are under investigation by the European Union’s drugs regulator after a small number of reports of suicidal risks were referred to the watchdog.

The European Medicines Agency is looking at adverse events noted by the Icelandic Medicines Agency, including two cases of suicidal thoughts linked to the drugs Saxenda and Ozempic, the EMA said in a statement Monday. One additional case relating to thoughts of self-injury has been raised in connection with Saxenda. 

The EMA did not report any cases of suicide, and suicidal behavior is not currently listed as a side effect in the EU product information of these medicines.

The EMA said it would consider whether its review should be extended to other drugs in the same class, known as GLP-1 receptor agonists. Eli Lilly & Co.’s Mounjaro is among them, and other companies including Amgen Inc. and Pfizer Inc. are developing similar products.

Novo’s shares fell as much as 2.3% in Copenhagen. Lilly’s were little changed at the New York market open

The agency said it’s investigating the possible side effects in relation to patients who have used medicines containing the active ingredients semaglutide or liraglutide for weight loss. Novo’s latest hit weight-loss drug Wegovy also uses semaglutide. 

“The popularity of these drugs brings added scrutiny to the class,” Bloomberg Intelligence analyst Michael Shah said in an e-mail. “No red flags on this front were raised across the late-stage trials, and these events are anecdotal.”

Novo has entered the limelight over the last two years after Wegovy and sister diabetes drug Ozempic were found to induce significant weight loss, with celebrities and high-profile business personalities openly discussing their use of them. The popularity of the medicines has led to supply shortages and delays in launching the drugs in new markets.

The EMA also recently asked Novo for more data on the potential link between its GLP-1 hormone and thyroid cancer. In Wegovy’s safety information, the medication lists a potential risk of thyroid cancer, and people with a family history of certain serious conditions are advised not to take it. Patients may also experience inflammation of the pancreas or kidney injury. 

Novo said in a statement that patient safety is a “top priority” and it takes all reports of adverse events very seriously.

“GLP-1 receptor agonists have been used to treat type 2 diabetes for more than 15 years and for treatment of obesity for eight years, including Novo products such as semaglutide and liraglutide that have been on the market for more than 10 years,” a spokesperson said.

Saxenda, which contains liraglutide, is a weight-loss medication that was first approved for use in 2014. Approved to treat type 2 diabetes, Ozempic contains semaglutide, the same active ingedient in Wegovy, which was cleared in 2021.

Wegovy is currently available in the US, Denmark and Norway and is set to go on the market in Germany this month. While the drug is not yet sold in the UK, the government announced last month it was looking at making it more widely available than originally planned with a pilot program aimed at expanding weight-loss services.

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