Peptide · Research Monograph · Triple GLP-1/GIP/glucagon receptor agonist peptide (LY3437943)

GLP-3 RT

A triple-hormone agonist studied for weight loss and metabolic health

GLP-3 RT is a next-generation triple hormone agonist — hitting the GLP-1, GIP, and glucagon receptors at once — researched as one of the most powerful compounds yet studied for weight loss and metabolic health.

For laboratory research use only — not for human or animal use

Available in the Eon catalog — GLP-3 RT from $100.00 Certificate of analysis (PDF)

Molecular data

Molecular formulaC221H342N50O68
Molecular weight4731.32 Da
SequenceGLP-3 RT (LY3437943) — synthetic triagonist peptide; full sequence not disclosed on page
Sequence length39 residues
CAS / identifierLY3437943 (CAS 2381089-83-2)
Physical formLyophilized powder
Available sizes10mg, 15mg, 24mg, 30mg, 48mg, 60mg

How it works

GLP-1R

GLP-1 Receptor Agonism

Activates GLP-1 receptors to enhance glucose-dependent insulin secretion, suppress glucagon release, delay gastric emptying, and engage central appetite regulation pathways in the hypothalamus. This is the same pathway targeted by semaglutide and liraglutide.

  • Glucose-dependent insulin secretion
  • Delayed gastric emptying
  • Central appetite suppression
GIPR

GIP Receptor Agonism

Co-agonism at GIP receptors potentiates the metabolic effects of GLP-1 signaling, enhances lipid metabolism, and modulates adipose tissue remodeling. This dual GLP-1/GIP mechanism is shared with tirzepatide, but GLP-3 RT adds a third target.

  • Synergistic insulin potentiation
  • Lipid metabolism enhancement
  • Adipose tissue signaling
GCGR

Glucagon Receptor Agonism

The unique third target — glucagon receptor activation increases hepatic energy expenditure, promotes fatty acid oxidation, and drives thermogenesis. This differentiates GLP-3 RT from all dual agonists and may account for its superior weight reduction in trials.

  • Hepatic energy expenditure increase
  • Enhanced fatty acid oxidation
  • Thermogenic pathway activation

What the research shows

Metabolic

Obesity & Weight Management

GLP-3 RT demonstrated up to 24.2% body weight reduction at 48 weeks in the Phase 2 obesity trial — the largest reduction reported for any anti-obesity compound in a randomized trial at that time.

Jastreboff et al. 2023

Endocrine

Type 2 Diabetes

In subjects with T2DM, GLP-3 RT reduced HbA1c by up to 2.16% and fasting glucose by up to 69.1 mg/dL, with weight loss up to 16.94% — exceeding most dual-agonist results in comparable populations.

Panou et al. 2026

Hepatic

Liver Fat Reduction (MASLD/MASH)

GLP-3 RT has shown marked reductions in liver fat content in preclinical and early clinical data, positioning it as a candidate for metabolic dysfunction-associated steatotic liver disease research.

Malandris et al. 2026

Comparative

Triple vs Dual Agonism

Network meta-analysis shows GLP-3 RT achieved the largest weight loss and HbA1c reduction among all glucagon receptor agonists studied, surpassing survodutide, mazdutide, and cotadutide.

Abulehia et al. 2026

Specification

Compound ClassTriple GLP-1/GIP/Glucagon receptor agonist
Research NameLY3437943 (GLP-3 RT)
TargetsGLP-1R + GIPR + GCGR
FormLyophilized powder
Purity≥99% (HPLC verified)
TestingThird-party HPLC, Mass Spec, Endotoxin
Storage (lyophilized)-20°C for long-term stability
Storage (reconstituted)2–8°C, use within 14 days
SolubilityBacteriostatic water for reconstitution
COAIncluded with every order
Stability24 months from manufacture date when stored properly
AppearanceWhite to off-white powder
Molecular FormulaAvailable on request

Frequently asked questions

What is GLP-3 RT?

GLP-3 RT (LY3437943) is a first-in-class triple hormone receptor agonist. It simultaneously targets three receptors: GLP-1 (appetite and insulin), GIP (metabolic potentiation), and glucagon (energy expenditure). This triple mechanism distinguishes it from single-agonists like semaglutide and dual-agonists like tirzepatide.

How does GLP-3 RT differ from semaglutide and tirzepatide?

Semaglutide (Ozempic/Wegovy) targets GLP-1 only. Tirzepatide (Mounjaro/Zepbound) targets GLP-1 + GIP (dual agonist). GLP-3 RT targets GLP-1 + GIP + Glucagon (triple agonist). In the Phase 2 trial, GLP-3 RT achieved 24.2% body weight reduction at 48 weeks — higher than any published result for semaglutide (~15%) or tirzepatide (~22%) at comparable timepoints.

What were the key Phase 2 trial results?

In the Jastreboff et al. 2023 NEJM trial (n=338, 48 weeks): the 12mg dose produced 24.2% mean body weight reduction. 92% of participants lost ≥5% body weight, 75% lost ≥10%, and 60% lost ≥15%. The effect was dose-dependent, with even the 1mg dose achieving 8.7% reduction.

Is GLP-3 RT FDA approved?

No. GLP-3 RT is currently in Phase 3 clinical trials (the TRIUMPH program). GLP-3 RT is a research compound sold exclusively for in vitro laboratory research. It is not FDA approved and should not be confused with approved medications.

How should GLP-3 RT be stored?

Store lyophilized at -20°C for long-term stability. After reconstitution with bacteriostatic water, refrigerate at 2-8°C and use within 14 days. Protect from direct light and avoid repeated freeze-thaw cycles.

Literature

  • NEJM Triple-Hormone-Receptor Agonist GLP-3 RT for Obesity — A Phase 2 Trial 2023 · Jastreboff AM et al. · PMID: 37366315
  • Review GLP-3 RT in type 2 diabetes mellitus and obesity: an overview 2026 · Panou T et al.
  • Meta-Analysis Comparative Efficacy and Safety of Glucagon Receptor Agonists: A Network Meta-Analysis 2026 · Abulehia A et al.
  • Preclinical GLP-3 RT Shows Multiple Metabolic Benefits in Diet-Induced Obese MASH Mouse and Hamster Models 2026 · Briand F et al.

For laboratory research use only. Not a drug, supplement, or medical product; not for human or animal use. All findings referenced are from published preclinical/laboratory research.