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Study wrapper · #861

Tirzepatide compared with semaglutide in obesity disease: a subpopulation analysis applying Japan Society for the Study of Obesity criteria in the global SURMOUNT-5 trial.

Kitamoto T, Yoshino M, Shingaki T, et al. Current medical research and opinion. 2026.

Editor's note

A prespecified subpopulation analysis of the randomized SURMOUNT-5 trial, applying Japanese obesity criteria, found tirzepatide produced markedly greater weight loss than semaglutide (roughly 20% versus 13% at 72 weeks) with a comparable, mostly gastrointestinal safety profile. As a head-to-head RCT-derived comparison this carries real weight, though it is a subgroup of 383 and industry-sponsored, so the headline gap should be read as consistent with rather than independent confirmation of the main trial. Strong signal on relative efficacy for peptide readers.

Plain-language abstract

In a head-to-head trial subgroup, people on tirzepatide lost about 20% of their body weight over 72 weeks versus about 13% on semaglutide, with similar side-effect profiles.