A systematic review and meta-analysis of incretin-based dual and triple agonists (tirzepatide, retatrutide, mazdutide) for obesity management. Aggregates efficacy and safety data from randomized trials, quantifying weight loss outcomes and adverse event rates across agents and doses.
Abstract
Incretin-based dual and triple agonists have emerged as effective options for obesity management, offering enhanced weight loss through multi-receptor agonism. However, data on their efficacy and safety remain limited. We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of these emerging agents. A comprehensive literature search was conducted using PubMed, the Cochrane Library, and Google Scholar from inception to June 2025 to identify randomized controlled trials evaluating tirzepatide, retatrutide, or mazdutide in obese adults. Clinical outcomes were assessed using the random-effects model and pooled as mean differences (MDs) or risk ratios (RRs) with 95% confidence intervals (CIs). A total of 10 randomized controlled trials, including 3236 participants, were analyzed. Incretin polyagonists significantly reduced body weight compared to placebo (MD -11.47; 95% CI: -14.00 to -8.95). Significant reductions were also observed in waist circumference (MD -9.40; 95% CI: -11.91 to -6.89), glycated hemoglobin (MD -0.96; 95% CI: -1.16 to -0.75), and fasting plasma glucose (MD -26.89 mg/dL; 95% CI: -33.48 to -20.30). However, the use of dual and triple agonists was associated with a higher risk of any adverse events (AEs) (RR 1.13; 95% CI: 1.08-1.19), including gastrointestinal AEs (nausea, vomiting, diarrhea, constipation), AEs leading to withdrawal (RR 1.96; 95% CI: 1.17-3.30), and hypoglycemic episodes (RR 3.08; 95% CI: 1.61-5.89). No significant difference was found in serious AEs (RR 0.87; 95% CI: 0.65-1.14). In conclusion, incretin-based polyagonists were associated with significant weight reduction and improved metabolic outcomes compared to placebo.