What is GLP-3RT?
GLP-3RT is a single peptide that activates three metabolic hormone receptors at once. Here is how triple agonism works, how it compares with single and dual agonists, and what research has reported so far.
At a glance
- Class
- Triple receptor agonist (GLP-1, GIP and glucagon)
- Studied as
- Retatrutide, development code LY3437943
- Receptors
- GLP-1R, GIPR and GCGR
- Half-life
- Long enough for once-weekly dosing in clinical studies 1
- Appearance
- White lyophilized powder
- Our fill sizes
- 10mg, 30mg, 60mg
Three receptors, one molecule
GLP-3RT is designed to act on three receptors that help regulate appetite, blood glucose and energy use:
- GLP-1 receptor. GLP-1 is released by the gut after a meal. It boosts insulin secretion when glucose is high, slows stomach emptying and signals fullness.
- GIP receptor. GIP is the second gut incretin hormone. It also boosts glucose-dependent insulin secretion and acts on fat tissue.
- Glucagon receptor. Glucagon raises glucose output from the liver, but it also increases energy expenditure and fat use.
The idea behind a triple agonist is that glucagon's energy-expenditure effect adds to the reduced food intake driven by the two incretins. In obese mice, the molecule studied as retatrutide lowered body weight and improved glucose control, and the extra weight loss was attributed to glucagon-receptor-driven increases in energy expenditure.1 In cell assays it showed balanced glucagon and GLP-1 receptor activity, with stronger activity at the GIP receptor.1
Single, dual and triple agonists
| Type | Receptors | Example in research |
|---|---|---|
| Single agonist | GLP-1 | GLP-1 receptor agonists |
| Dual agonist | GIP + GLP-1 | Tirzepatide |
| Triple agonist | GIP + GLP-1 + glucagon | GLP-3RT (retatrutide) |
Each added receptor gives researchers another pathway to study, which is why triple agonists are often compared directly against dual agonists in metabolic models. Our tirzepatide overview covers the dual-agonist side.
What the research has reported
Discovery and first human data
The compound was developed by Eli Lilly under the code LY3437943. Its 2022 discovery paper described the cell and mouse findings above, and a first single-dose study in people found a safety profile similar to other incretin-based drugs, a pharmacokinetic profile supporting once-weekly dosing, and a fall in body weight that lasted up to day 43 after one dose.1
Phase 2 obesity trial
A 48-week phase 2 trial randomised 338 adults with obesity, or with overweight plus a weight-related condition, to weekly retatrutide or placebo. At the highest dose, mean body weight fell by 24.2%, compared with 2.1% with placebo. The most common side effects were gastrointestinal and were more frequent at higher doses.2
Phase 3 programme
Larger phase 3 trials, known as the TRIUMPH programme, followed. In May 2026 the developer reported topline results from the first, TRIUMPH-1, saying all tested doses met the trial's main weight-loss goals at 80 weeks; full peer-reviewed results were still to come.3 As of October 2026 retatrutide is not approved by the FDA, and these results are for an investigational medicine given under medical supervision.
Clinical results describe the investigational drug in supervised trials. Research-grade GLP-3RT is supplied for laboratory work only.
Where GLP-3RT is used in the lab
In laboratory and preclinical research, GLP-3RT is used to study body-weight regulation and food intake in animal models, energy expenditure, glucose homeostasis and insulin secretion, and to compare receptor pharmacology against single and dual agonists such as tirzepatide. Researchers working on metabolism often pair it with MOTS-C or NAD+ in studies of cellular energy.
Handling GLP-3RT in the lab
Lyophilized GLP-3RT is stable stored frozen at −4 °F and protected from light. Let a vial reach room temperature before opening, reconstitute with bacteriostatic water added slowly down the side of the vial, swirl rather than shake, and keep the solution refrigerated at 36–46 °F.
Before using any lot, check its certificate of analysis. Our current GLP-3RT lot, VD-RT10-2610, tested at 99.40% purity by HPLC with identity confirmed by LC-MS at VeriPure Labs (10mg vial tested). View the certificate ↗ or see every lot on our lab reports page.
Frequently asked questions
Is GLP-3RT the same as retatrutide?
GLP-3RT is our catalog name for a GLP-1 / GIP / glucagon triple-agonist research peptide. In the scientific literature, the best-studied compound of this class is retatrutide (LY3437943), which is the molecule the studies cited here describe.
How is GLP-3RT different from tirzepatide?
Tirzepatide activates two receptors, GIP and GLP-1. GLP-3RT adds the glucagon receptor, which in preclinical work is linked to increased energy expenditure.
Is retatrutide an approved medicine?
Not as of October 2026. Retatrutide has completed phase 2 trials and phase 3 trials are reporting, but it has not been approved by the FDA.
Is GLP-3RT for human use?
No. Vivid DNA supplies GLP-3RT strictly for laboratory research. It is not a drug, food or supplement, and is not for human or veterinary use.
References
- Coskun T, Urva S, Roell WC, et al. LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist for glycemic control and weight loss: from discovery to clinical proof of concept. Cell Metabolism. 2022;34(9):1234–1247. PubMed 35985340 ↗
- Jastreboff AM, Kaplan LM, Frías JP, et al. Triple-hormone-receptor agonist retatrutide for obesity: a phase 2 trial. New England Journal of Medicine. 2023;389(6):514–526. doi:10.1056/NEJMoa2301972 ↗
- HCPLive. Retatrutide meets weight loss endpoints in phase 3 obesity trial (TRIUMPH-1 topline results). May 21, 2026. hcplive.com ↗
More research overviews
Research use only. Vivid DNA products are sold strictly for laboratory research. They are not drugs, foods, cosmetics or supplements, are not for human or veterinary use, and are not intended to diagnose, treat, cure or prevent any disease. Clinical results described here refer to investigational or approved medicines studied under medical supervision, not to research-grade material. This article summarises published research and has not been evaluated by the Food and Drug Administration.