Possible Thyroid Cancer Risks with Semaglutide Triggers Safety Signal

A European drug authority has requested that drug manufacturers provide more information about the possible links between semaglutide — found in diabetes and weight loss medications like Ozempic and Wegovy — and thyroid cancer.

Last month, the European Medicines Agency (EMA) — a European Union (EU) agency in charge of evaluating and supervising pharmaceutical medications — raised concerns about a possible risk of thyroid cancer in people using glucagon-like peptide-1 (GLP-1) receptor agonists, including semaglutide.

Semaglutide is the active ingredient in popular diabetes and weight loss drugs like Ozempic and Wegovy.

In a document published on May 8, 2023, the EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) states that makers of semaglutide, including Novo Nordisk, AstraZeneca, Eli Lilly, and others, must provide supplementary information on the drug by July 26, 2023.

The study prompting the EMA’s safety signal was published in Diabetes Care in February. According to the paper, researchers found that people using GLP-1 receptor agonists for one to three years may have an increased risk of all types of thyroid cancers.

Moreover, previous 2022 research found an association between GLP-1 receptor agonists and thyroid cancers and malignant pancreatic neoplasms.

However, these and other studies have not provided conclusive evidence about whether GLP-1 receptor agonists like semaglutide pose a thyroid cancer risk.

Still, prescribing information included with Ozempic and Wegovy advises consumers about the potential adverse effects of these drugs. For example, both drugs warn that semaglutide causes thyroid C-cell tumors in rodents, but it’s unknown if it causes this type of tumor in humans.

Other precautions listed include warnings that pancreatitis, gallbladder disease, and kidney injuries have occurred in people using semaglutide.

The EMA issues a safety signal when adverse events occur in people using an approved drug, or research indicates there may be an association between an adverse event and a medication. However, a safety signal does not mean there’s a direct link between semaglutide and thyroid cancer.

But it does trigger more investigations to determine the drug’s safety.

According to a Reuters report, a spokesperson for Eli Lilly states they have previously acknowledged the potential thyroid cancer risks related to GLP-1 receptor agonists and are working with regulatory agencies to conduct two studies investigating that link.