How much weight did participants lose?
The randomised trial enrolled 338 adults with obesity, or overweight with a weight-related condition. The table shows estimated mean reductions from starting body weight at 48 weeks. Study-arm labels describe the research; they are not dosing instructions.
| Study arm | Weight reduction |
|---|---|
| Retatrutide 1 mg | 8.7% |
| Retatrutide 4 mg (pooled) | 17.1% |
| Retatrutide 8 mg (pooled) | 22.8% |
| Retatrutide 12 mg | 24.2% |
| Placebo | 2.1% |
Sources: Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial
Does 24.2% weight loss mean 24.2% fat loss?
No. Body weight includes fat, lean tissue and water. This endpoint does not isolate fat loss. For a purely illustrative starting weight of 100 kg, a 24.2% reduction equals 24.2 kg; it does not predict a reader’s outcome.
What were the side effects and limitations?
Gastrointestinal adverse events were common and dose-related. Heart-rate increases were also reported. A 48-week phase 2 trial cannot settle long-term safety or outcomes after treatment ends. Lilly funded the study. These findings concern supervised trial participants and the trial material, not Zynx products.
Sources: Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial
Sources and further reading
This guide summarises selected sources. Original publications contain the full methods, results and disclosures; the selection is not a systematic review.
- Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial (external)
Jastreboff et al. New England Journal of Medicine (2023). DOI: 10.1056/NEJMoa2301972. Randomised, placebo-controlled phase 2 trial.
Continue exploring
- Retatrutide fat loss: body-composition study explained
- Retatrutide and liver fat: MRI trial results explained
- Retatrutide research: trials, outcomes and limitations
Published study records · Quality documentation · Research peptide catalogue