New study ties weight-loss drugs Wegovy, Ozempic to serious gastrointestinal conditions
CBC
Medicines in the same class as Novo Nordisk's popular weight-loss therapy Wegovy may carry an increased risk of pancreatitis, intestinal blockage and stomach paralysis compared to an older obesity drug, according to a study published on Thursday.
The study focused on two drugs from the class known as GLP-1 inhibitors, which help lower blood sugar levels for people with Type 2 diabetes: semaglutide is the active ingredient in Wegovy as well as Novo's diabetes drugs Ozempic and Rybelsus; liraglutide is the active ingredient in the company's earlier obesity medicine Saxenda and diabetes drug Victoza.
Nearly five in every 1,000 users of semaglutide drugs developed pancreatitis, compared to one of every 1,000 users of bupropion-naltrexone, the active ingredients in the weight-loss drug Contrave, according to a report in the JAMA medical journal. Contrave was approved in the U.S. in 2014 and in Canada in 2018.
For liraglutide, there were about eight cases of pancreatitis per 1,000 users.
Pancreatitis, or inflammation of the pancreas, can cause severe abdominal pain.
For stomach paralysis, researchers found roughly nine cases among every 1,000 users of semaglutide and about seven in liraglutide patients, compared with three among the same number of those taking bupropion-naltrexone.
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GLP-1 inhibitor medications mimic the actions of GLP-1, a natural hormone that helps control blood sugar levels in people with diabetes.
Mahyar Etminan, an epidemiologist at the University of British Columbia and senior author of the study, said up to two per cent of patients who used semaglutide and liraglutide medications to lose weight developed gastrointestinal problems.
"When you have millions of people taking them, that one per cent starts becoming a relatively big number," he said. "One of my main concerns is that they're long-term adverse events for which we really don't have much data, especially for those who are taking them just for weight loss and not for diabetes."
People with diabetes were not included in the study.
The study was observational, so it can only show associations, not whether the drugs caused the conditions.
The results of this study are consistent with effects observed in clinical trials in obese patients, said Penny Ward, an independent pharmaceutical physician and visiting professor in pharmaceutical medicine at King's College London in the U.K.
Ward told Science Media Centre that the study wasn't designed to assess all possible side-effects of the treatments.