Retatrutide, described as the 'Godzilla' of weight-loss drugs, could help improve blood sugar levels, reduce inflammation, and cut a person's body weight by a quarter, according to the largest study of its kind. The drug is not yet approved by any regulatory agency.
The drug mimics three key gut hormones: GLP-1, GIP, and glucagon, which help control appetite, blood sugar, and metabolism. Unlike other drugs, Retatrutide also engages the glucagon receptor, which helps increase energy expenditure.
Results from an 80-week phase 3 trial, involving 2,047 adults with obesity and type 2 diabetes across eight countries, showed participants on the highest 12 mg dose lost an average of 18.8% of their body weight. Almost half (47%) of those on the 12 mg dose shed at least 20% of their starting weight, and almost a third (31%) lost at least 25%.
Additionally, 72% of participants on Retatrutide achieved an HbA1c of 6.5% or lower, a standard threshold for diagnosing type 2 diabetes, compared to 29% in the placebo group. The drug also improved cardiometabolic risk factors, including blood pressure and lipid profiles, and reduced a marker of inflammation.
The most frequently reported adverse events were gastrointestinal, with diarrhoea affecting 27-34% of participants in the Retatrutide groups and nausea affecting 14-28%.