Glucagon receptor-like peptide receptor agonists, GLP-1 RAs, are one of the most commonly used drugs for type-2 diabetes mellitus. The clinical guidelines recommend GLP-1 RAs as adjunct to diabetes therapy in patients with chronic kidney disease, presence or risk of atherosclerotic cardiovascular disease, obesity, and other cardiometabolic conditions. The weight loss seen in clinical trials has been explored further in healthy individuals, putting GLP-1 RAs on track to be the next weight loss treatment. Although the adverse event profile is relatively safe, most GLP-1 RAs come with a labeled black boxed warning of the risk of thyroid cancers, based on animal models and some postmarketing case reports in humans. Considering the increasing popularity of this drug class and its expansion into a new popular indication, a further review of most recent postmarketing safety data is warranted to quantify thyroid hyperplasia and neoplasms instances. In this study we analyzed over eighteen million reports from United States Food and Drug Administration Adverse Event Reporting System and identified 17,653 relevant GLP-1 RA monotherapy reports to provide the evidence of significantly increased propensity for thyroid hyperplasias and neoplasms in patients taking GLP-1 RA as monotherapy when compared to patients taking sodium-glucose cotransporter-2 inhibitor monotherapy.

The authors have declared no competing interest.

This work was funded in part by NIH R35GM131881.

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