Real-World Weight-Loss Outcomes in Weight-Reduced Patients Treated With Tirzepatide.

OBJECTIVE: This study compared weight-loss outcomes in patients prescribed tirzepatide by weight-loss status and assessed results among patients transitioning from semaglutide. METHODS: This retrospective cohort study analyzed 6-month weight-loss outcomes in adults treated with tirzepatide between May 2022 and January 2023. Patients were classified as weight-reduced if they had lost ≥ 10% total body weight (TBW) before starting tirzepatide. Among those who switched from therapeutic semaglutide (≥ 1.7 mg weekly for ≥ 1 month), reasons for switching were categorized as non-response (< 5% weight loss after ≥ 3 months), plateau (≥ 5% loss followed by weight stabilization), or other. RESULTS: Of 941 charts, 293 (31.1%) met inclusion criteria (65% female; mean age 52 years; mean BMI 36.15 kg/m). Weight-reduced patients (n = 133) lost 7.2% TBW versus 10.3% in non-weight-reduced patients (n = 160; p < 0.001). When analyses were stratified by type 2 diabetes (T2D) status, this difference remained significant among patients without T2D. Sixty-one patients switched from semaglutide due to non-response or plateau and lost 5.3% TBW. Those switching at a plateau (n = 28) lost 8.1% versus 2.9% for non-responders (n = 33; p < 0.001). CONCLUSIONS: Tirzepatide produced meaningful weight loss across groups but outcomes varied based on weight-reduction status, T2D status, and prior response to semaglutide.