Retatrutide

Investigational

Also known as: LY3437943, Eli Lilly Triple Agonist

GLP-1/GIP/Glucagon Triple Agonist

Last reviewed: April 28, 2026

An investigational triple-agonist peptide developed by Eli Lilly that targets GLP-1, GIP, and glucagon receptors simultaneously. Phase 3 clinical trials are underway, with early results showing unprecedented weight loss efficacy.

Mechanism of Action

Activates three metabolic hormone receptors: GLP-1 (appetite suppression, insulin secretion), GIP (enhanced insulin response, fat metabolism), and glucagon (increased energy expenditure, fat oxidation). The triple mechanism may produce greater weight loss than dual agonists.

Common Uses

  • Weight management (investigational)
  • Type 2 diabetes (investigational)
  • Metabolic syndrome (investigational)

Known Risks

  • Still in clinical trials — full safety profile unknown
  • GI side effects (nausea, diarrhea, vomiting) reported in trials
  • Not yet approved for any indication
  • Long-term effects unknown

Regulatory Status

Investigational

Currently in Phase 3 clinical trials. Phase 2 results showed up to 24% body weight loss at 48 weeks. FDA approval timeline uncertain but potentially 2027-2028.

Common Protocols

Protocol information is for educational reference only. Dosing varies significantly by individual, condition, and physician guidance. Always work with a licensed healthcare provider.

Subcutaneous injection (investigational)

Typical Dose

2 mg → 12 mg (titrated in trials)

Frequency

Once weekly

Cycle Length

Ongoing — not commercially available

Currently only available through clinical trial enrollment. Not available through compounding pharmacies — investigational compounds cannot be compounded. Check clinicaltrials.gov for active TRIUMPH trials.

Related Compounds

Research References

Related Articles

This information is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy. Data is compiled from published research and regulatory sources and may not reflect the most recent developments.