Study wrapper · #935
Efficacy of GLP-1 analog peptides, semaglutide, tirzepatide, and retatrutide on MC4R deficient obesity and their comparison.
Hitaka K, Sugawara T, Matsumoto M, et al. International journal of obesity (2005). 2026.
DOI: 10.1038/s41366-026-02025-2PubMed: 41733725
Editor's note
This animal study directly compares three tracked peptides in MC4R-knockout mice, a model of severe genetic obesity, so all three are central subjects. All reduced body weight and improved insulin, lipid, and liver markers, with tirzepatide showing the greatest effect. Findings are preclinical, and the authors note the model aligns with clinical observations.
Plain-language abstract
In mice lacking the MC4R gene, semaglutide, tirzepatide, and retatrutide all reduced body weight and improved metabolic markers, with tirzepatide producing the largest weight reduction.
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