Study wrapper · #1315
Tirzepatide non-response with subsequent semaglutide response in class 2 obesity.
Editor's note
A single case, so it establishes that a tirzepatide non-responder can respond to semaglutide - not how often that happens or why. The proposed GIP receptor mechanism is inference from the literature rather than anything measured in this patient, and the authors themselves flag that the HOMA-IR threshold idea needs prospective testing. Useful as a counterweight to the assumption that the dual agonist is universally the stronger choice, which the head-to-head trial data supports only on average.
Plain-language abstract
Clinicians describe a 40-year-old man with class 2 obesity and marked insulin resistance who lost under 5 percent of his body weight despite six months of tirzepatide escalated to 15 mg weekly. After switching to semaglutide 2.4 mg weekly, he lost 20 percent of his body weight over six months, with fasting glucose and insulin resistance measures returning to normal. The authors propose that reduced GIP receptor signalling in fat tissue, alongside intact central GLP-1 signalling, could explain the pattern.