Strong · human
This living systematic review and network meta-analysis, commissioned by the American College of Physicians, synthesized evidence from 69 randomized controlled trials involving 112,511 adults with overweight or obesity (BMI ≥25 kg/m²) to compare pharmacologic weight-management treatments. Drugs examined included GLP-1 receptor agonists (semaglutide, liraglutide, dulaglutide, exenatide, lixisenatide), dual agonists (tirzepatide, retatrutide, semaglutide-cagrilintide), and other agents (naltrexone-bupropion, phentermine, phentermine-topiramate, orforglipron), with or without lifestyle intervention. The review found that nearly all studied interventions produced greater weight loss than placebo and/or lifestyle intervention alone. Semaglutide was found to probably reduce mortality and major adverse cardiovascular events (MACE). Semaglutide and tirzepatide demonstrated the greatest weight loss in both pairwise and network meta-analyses. However, nearly all active treatments were also associated with more treatment discontinuations due to adverse events compared with placebo. The authors noted that evidence for critical outcomes such as mortality, MACE, and serious adverse events remained limited, and direct head-to-head comparisons between treatments were scarce. Thirty-seven of the 69 included studies were rated at low risk of bias. The living review design allows for ongoing evidence updates as new trials emerge.
Annals of internal medicine · Jun 2026DOI ↗ Strong · human
This systematic review and meta-analysis pooled data from 10 randomized controlled trials (3,236 participants) to evaluate the efficacy and safety of incretin-based dual and triple receptor agonists — specifically tirzepatide, retatrutide, and mazdutide — in overweight or obese adults. The authors searched PubMed, the Cochrane Library, and Google Scholar through June 2025 and applied a random-effects model to pool outcomes. The study found that these agents were associated with statistically significant reductions in body weight (mean difference: −11.47 kg), waist circumference (−9.40 cm), glycated hemoglobin (−0.96%), and fasting plasma glucose (−26.89 mg/dL) compared to placebo. On the safety side, treatment was associated with a higher risk of any adverse event (RR 1.13), gastrointestinal adverse events (nausea, vomiting, diarrhea, constipation), treatment discontinuation due to adverse events (RR 1.96), and hypoglycemic episodes (RR 3.08). No significant difference in serious adverse events was observed. Limitations include the relatively small number of pooled trials, heterogeneity inherent across different agents and doses, and the restriction to placebo-controlled comparisons, which limits conclusions about comparative effectiveness between agents.
Cardiology in review · Feb 2026DOI ↗ Strong · human
This systematic review and meta-analysis pooled data from 25 randomized controlled trials (RCTs) involving approximately 2,600 patients to evaluate the effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) — including liraglutide, exenatide, dulaglutide, semaglutide, tirzepatide, efinopegdutide, survodutide, and retatrutide — on metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH). Across a median treatment period of 24 weeks, the authors reported that GLP-1RAs were associated with a statistically significant mean reduction in liver fat content of 5.21%, with retatrutide showing the largest effect. Histological analyses suggested significant improvements in steatosis, hepatocellular ballooning, and lobular inflammation, though improvements in fibrosis did not reach statistical significance. Liver enzymes (ALT, AST, γ-GT) and liver stiffness also improved significantly, with semaglutide showing the most pronounced effect on stiffness. No liver-related adverse drug effects were identified. Limitations include heterogeneity across trials, variable treatment durations, and the relatively short median follow-up, which may be insufficient to capture fibrosis outcomes. The evidence base is derived entirely from RCTs in human populations.
The Journal of clinical endocrinology and metabolism · Sep 2025DOI ↗ Strong · human
This Bayesian network meta-analysis (NMA) synthesized evidence from 19 randomized controlled trials (RCTs) enrolling 29,506 adults with overweight or obesity (BMI ≥ 25 kg/m²) to compare the weight-loss efficacy and safety of GLP-1 receptor agonists (liraglutide, semaglutide), dual agonists (tirzepatide, survodutide), and the triple agonist retatrutide against placebo over at least 36 weeks. The study found that retatrutide and dual agonists achieved equivalent mean weight loss (approximately −11.0 kg), both outperforming GLP-1 receptor agonists (approximately −9.0 kg). Retatrutide showed the highest odds of achieving ≥15% weight loss (OR 54.6), followed by dual agonists (OR 16.4) and GLP-1 receptor agonists (OR 9.0). However, retatrutide was also associated with the highest adverse event risk. Meta-regression analyses indicated that type 2 diabetes mellitus attenuated weight loss across all drug classes, while female-dominant and higher-BMI cohorts showed enhanced outcomes. Limitations include indirect comparisons inherent to NMA methodology, heterogeneity across trials in baseline characteristics, and the fact that retatrutide data remain from earlier-phase trials. The authors recommend individualized treatment selection based on patient-specific factors.
Obesity (Silver Spring, Md.) · Jul 2025DOI ↗