Retatrutide
Regulatory
Legal Status in 2026
In active US clinical trials (Phase 2 or later); no FDA approval yet.
This compound is under active investigation in US clinical trials (Phase 2 or later) and has not yet received FDA approval. It is not legally available for prescription or compounding outside of enrolled clinical trial settings. The risk-benefit profile is not yet established for the general population.
About
About Retatrutide
Retatrutide is a triple agonist targeting GLP-1, GIP, and glucagon receptors simultaneously, representing the most mechanistically advanced anti-obesity peptide in late-stage clinical development. Phase II trials reported mean body weight reductions of 24% over 48 weeks — the largest pharmacological weight loss ever recorded in a randomized controlled trial. It is being developed by Eli Lilly and is expected to enter Phase III trials in 2025–2026.
Science
Mechanism of Action
Simultaneously activates GLP-1 receptors (appetite suppression, insulin secretion), GIP receptors (enhanced insulin response, adipocyte signaling), and glucagon receptors (increased energy expenditure and hepatic glucose regulation), producing synergistic metabolic effects beyond dual agonists.
Dosing
Typical Protocol
Phase II doses ranged from 1–12 mg subcutaneous injection once weekly; not yet commercially available.
⚠ Protocol information is for educational purposes only. Dosing must be determined by a licensed physician based on individual health status and goals.
Evidence
Evidence Tier
Evidence from randomized controlled trials (RCTs) or large observational studies in humans. This is the gold standard — effects have been measured in controlled conditions and results are peer-reviewed and reproducible.
Availability
Provider availability
Retatrutide is in active clinical trials and is not available through legitimate US prescribing or compounding channels outside an enrolled trial, so Vial does not list providers for it.
Compound comparisons
Compare Retatrutide
Retatrutide set against other compounds people weigh it against.
This page evaluates compliance signals, not clinical outcomes. Consult a licensed physician before starting any therapy, medication, or treatment. Vial does not provide medical advice.