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Assessment of thyroid cancer risk associated with glucagon-like peptide 1 receptor agonist use.

Diabetes Obes Metab · 2026

Last updated 2026-05-28

A review of clinical trials involving 101,732 participants and post-marketing data found no clear link between GLP-1 drugs like liraglutide or semaglutide and thyroid cancer risk. Across trials, the reported thyroid cancer cases were low, with hazard ratios of 1.70 and 1.83 compared to placebos or other treatments, but confidence intervals included 1, meaning the results were not statistically significant. Real-world data from a U.S. database also showed no increased risk, with a hazard ratio of 0.87 when comparing GLP-1 drugs to another diabetes medication class.

AI summary of the abstract below.

JournalDiabetes Obes Metab, 2026
Citations2
Molecules

Abstract

AIMS: Published literature has raised concerns regarding a causal association between glucagon-like peptide 1 receptor agonist (GLP-1RA) use and thyroid cancer risk in adults. In this analysis, we evaluated the association between thyroid cancer risk and GLP-1RA use. MATERIALS AND METHODS: Our evaluation included data from (i) 93 liraglutide or semaglutide phase 2 and 3 clinical trials, of which six were cardiovascular outcome trials (CVOTs); (ii) post-marketing surveillance from the Novo Nordisk safety database (evaluating data for liraglutide and semaglutide); and (iii) the US Merative™ MarketScan® Commercial Database. Hazard ratios (HRs) were estimated for overall thyroid cancer risk for treatment groups in the clinical trials and for individuals with type 2 diabetes treated with any GLP-1RAs versus sodium-glucose cotransporter-2 inhibitors (SGLT2is) for the real-world data. RESULTS: Data from all clinical trials across 101 732 participants (totalling 206 950 patient-years of exposure [PYE]) reported low numbers of thyroid cancer events; across all trials, HRs were 1.70 (95% confidence interval [CI] 0.99, 3.03) and 1.83 (0.70, 6.71) for pooled GLP-1RA versus pooled placebo and active comparator, respectively. For CVOTs, the HR (95% CI) for pooled GLP-1RA versus pooled placebo was 1.41 (0.72, 2.81). Post-marketing surveillance data showed a low thyroid cancer reporting rate of 0.001 cases/100 PYE and did not support an association between liraglutide or semaglutide exposure and the number of thyroid cancer events. Analysis of the US Merative™ MarketScan® Commercial Database reported an HR of 0.87 (95% CI 0.58, 1.29) for the occurrence of thyroid cancer in individuals using any GLP-1RAs versus SGLT2is. CONCLUSIONS: The totality of data analysed did not suggest an association between liraglutide or semaglutide use and thyroid cancer risk in adults.

Verbatim abstract via PubMed 41287564 ↗