Comparing GLP-1 Agonists, Dual Agonists, and Retatrutide for Weight Loss

The global prevalence of overweight and obesity continues to rise, posing significant public health challenges and increasing the risk of numerous comorbidities like type 2 diabetes and cardiovascular disease. While lifestyle interventions are foundational, pharmacological treatments, particularly GLP-1 receptor agonists (GLP-1 RAs), have shown remarkable efficacy. However, with the emergence of newer dual agonists (targeting GLP-1 and GIP) and triple agonists (targeting GLP-1, GIP, and glucagon), there's a critical need for a comprehensive, head-to-head comparison of their relative efficacy and safety profiles to guide clinical decision-making and future therapeutic strategies.

The NMA revealed significant differences in weight loss efficacy among the evaluated agents. Retatrutide demonstrated superior weight reduction, achieving an average body weight loss of 24.2% from baseline. Tirzepatide followed closely with an average reduction of 19.5%, while semaglutide resulted in a 15.0% average weight loss. These differences were statistically significant, with retatrutide showing a 4.7% greater weight loss compared to tirzepatide (p<0.001) and a 9.2% greater loss compared to semaglutide (p<0.001). All agents exhibited a generally tolerable safety profile, primarily characterized by gastrointestinal adverse events (nausea, vomiting, diarrhea), with discontinuation rates due to adverse events being 15% for retatrutide, 12% for tirzepatide, and 10% for semaglutide. The most impactful finding was that retatrutide consistently emerged as the most efficacious agent for weight loss, offering a 1.6-fold greater weight reduction compared to semaglutide and a 1.2-fold greater reduction compared to tirzepatide.