Estimate the phase 2 retatrutide signal — without pretending it predicts you.
Enter a starting weight and compare the published 24-week and 48-week phase 2 obesity-trial averages. This tool is education only: retatrutide is investigational, not FDA-approved, and not a consumer peptide recommendation.
Retatrutide average weight-change calculator
The numbers below use the published mean percent body-weight changes from the 48-week phase 2 obesity trial: placebo, 1 mg, combined 4 mg, combined 8 mg, and 12 mg retatrutide groups. They are trial averages, not personalized forecasts.
At 48 weeks, the 12 mg group averaged about 24.2% body-weight loss in the phase 2 trial. For a 220 lb starting weight, that equals about 53.2 lb, ending near 166.8 lb.
What makes retatrutide different?
Triple agonist · pipeline status · safety questions
Three receptor pathways
Retatrutide activates GLP-1, GIP, and glucagon receptors. The glucagon component is one reason researchers are watching weight, lipid, energy-expenditure, and liver-fat endpoints closely.
Powerful early signal
The phase 2 obesity trial reported dose-responsive average weight loss through 48 weeks, with the 12 mg group averaging about 24.2% body-weight loss versus about 2.1% with placebo.
Still investigational
The hype gap is access. A real phase 3 program is not the same as a safe consumer product. Gray-market “retatrutide” does not inherit Lilly’s manufacturing, oversight, or trial evidence.
The full retatrutide guide
Go deeper on the triple-agonist mechanism, obesity and diabetes phase 2 data, body composition questions, liver-fat rationale, phase 3 watchlist, gray-market risk, and clinician questions.