Phase 3 trial results show retatrutide, a weekly injectable drug for type 2 diabetes, produced more than four times greater weight loss and twice the blood-sugar improvement compared to placebo. The medication works by mimicking three gut hormones (GLP-1, GIP, and glucagon) to suppress appetite, improve blood-sugar control, and increase energy expenditure—a mechanism broader than existing diabetes drugs like Ozempic and Mounjaro.