Tirzepatide for Obesity in Adults ≥ 65 Years: A Post Hoc Analysis of the SURMOUNT and SUMMIT Clinical Trials

Abstract

Aims: Tirzepatide is a once-weekly glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist (RA) approved for weight management in adults with obesity. Data on older adults remain limited, however. This study aimed to examine tirzepatide's safety and efficacy in adults aged ≥ 65 years with obesity across Phase 3 clinical trials. Materials and Methods: This post hoc analysis evaluated results from the SURMOUNT-1 through -5 (including SURMOUNT-1 3-year study), SURMOUNT-OSA and SUMMIT trials. Efficacy and safety of tirzepatide were compared between participants aged ≥ 65 years and < 65 years. Efficacy outcomes, analysed by study, were assessed at varying points depending on trial design. Safety outcomes in the pooled population were assessed throughout the treatment period. Results: Tirzepatide treatment was associated with clinically meaningful weight reduction and favourable treatment differences in cardiometabolic risk factors and quality-of-life measures in adults ≥ 65 years, with broadly comparable results to those observed in adults < 65 years. No clinically meaningful differences in adverse event (AE) rates between tirzepatide and placebo were observed in older adults for gastrointestinal tolerability, falls, fractures, depression outcomes, pancreatitis, and renal, hepatic, gallbladder and biliary-related AEs. No clinically relevant risks beyond those inherent to older age were detected in adults ≥ 65 versus < 65 years. Conclusions: In this post hoc analysis from Phase 3 clinical trials, efficacy and safety profiles of tirzepatide in adults aged ≥ 65 years with obesity were comparable to those in adults aged < 65 years. This study supports tirzepatide's use in older adults when considering risks and benefits.