Investigational GLP-1/GIP/GCG

Retatrutide — LY3437943 / Triple Agonist

Weight Loss & Metabolic Health. Retatrutide is a first-in-class triple hormone receptor agonist activating GLP-1, GIP, and glucagon receptors simultaneo...

Sequence
39 Amino Acids
Category
Investigational GLP-1/GIP/GCG
Primary Use
Weight Loss
Administration
SubQ

What Is Retatrutide?

Retatrutide is a first-in-class triple hormone receptor agonist activating GLP-1, GIP, and glucagon receptors simultaneously. Developed by Eli Lilly, Phase II data showed up to 24% body weight reduction at 48 weeks — exceeding both semaglutide and tirzepatide. It represents the next frontier in metabolic therapeutics.

GLP-1 GIP glucagon weight loss triple agonist

Mechanism of Action

Retatrutide's triple agonist mechanism targets three metabolic pathways. GLP-1 reduces appetite and slows gastric emptying. GIP enhances insulin secretion and fat metabolism. Glucagon receptor activation increases energy expenditure and hepatic fat oxidation. The combination produces additive or synergistic effects exceeding dual agonist approaches.

Key Research Findings

  • Weight loss — Phase II: mean 24.2% body weight reduction at 12mg/48 weeks, exceeding semaglutide and tirzepatide
  • Metabolic markers — Significant improvements in HbA1c, fasting glucose, and insulin resistance
  • Liver fat — Substantial reductions in hepatic steatosis markers with NAFLD/NASH implications
  • Blood pressure — Clinically meaningful reductions in systolic and diastolic BP across dose groups
  • Phase III — TRIUMPH program currently enrolling for obesity and T2D indications

Important: The evidence base for Retatrutide varies by application. Many findings are from preclinical (animal or in vitro) studies. Large-scale human clinical trials may not be completed. Always evaluate the quality of evidence before drawing conclusions.

Known Side Effects

GI effects predominate: nausea, diarrhea, vomiting, decreased appetite — generally mild-to-moderate and diminish over time. The glucagon component may theoretically increase hyperglycemia risk in non-diabetics, though not observed clinically at therapeutic doses.

Legal Status (2026)

Where to Buy Retatrutide for Research

These verified suppliers carry Retatrutide with third-party COAs and US-based shipping.

BP
BioPure Peptides
USA-made · 99%+ purity · WHO/GMP certified
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AP
Apollo Peptide Sciences
Oxnard, CA · Research-grade · Third-party verified
  • Ships within 48 hours via USPS Priority/Express
  • Full COAs available on every product
  • Free shipping on orders over $200
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MW
Midwest Peptide
Mission, KS · Same-day shipping · COAs on every page
  • Same-day UPS shipping from US facility
  • Free shipping on every order
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