peptidefix

Retatrutide

Also: LY3437943, GGG tri-agonist

Metabolic & weight
Legal status United KingdomNot approvedUnited StatesNot approvedAustraliaNot approved
Research on peptidefix

7 papers: 5 human studies, 2 animal studies.

Listed suppliers United Kingdom3United States4Australia8 Europe6
Checked 2026-11-03

Legal status as understood on this date. Listed, not endorsed. How we list.

Summary

Retatrutide is a synthetic peptide developed by Eli Lilly that acts on three hormone receptors at once: GLP-1, GIP and glucagon. It is an investigational drug in phase 3 clinical trials for obesity and type 2 diabetes and is not yet licensed anywhere. Its long duration of action comes from a fatty-acid chain attached to the peptide.

What it targets

Retatrutide activates the GLP-1, GIP and glucagon receptors, which between them influence appetite, insulin release and energy expenditure. In a 40-week phase 3 trial (TRANSCEND-T2D-1) in 537 adults with type 2 diabetes not controlled by diet and exercise, it lowered HbA1c and body weight more than placebo, with gastrointestinal effects the most common adverse events; the trial was funded by Eli Lilly, which develops retatrutide. In an earlier phase 2 substudy in adults with type 2 diabetes, it reduced total body fat mass measured by DXA compared with placebo and dulaglutide over 36 weeks. In diet-induced obese rats, combining it with cagrilintide lowered body weight and food intake more than either drug alone. A mouse study presented as a conference abstract reported reduced pancreatic tumour growth at a dose that did not cause weight loss; that finding has not been published as a full paper.

blood sugar (HbA1c) and body weight (phase 3, type 2 diabetes)body weight and fat mass (phase 2, type 2 diabetes)combination with cagrilintide (rats)pancreatic cancer growth (mice, conference abstract)

Clinical Research

Retatrutide Once Weekly in Adults with Knee Osteoarthritis Pain and Obesity
Schnitzer TJ, Hunter DJ, Conaghan PG, et al. (2026). New England Journal of Medicine. human two phase 3 randomised placebo-controlled trials in adults with painful knee osteoarthritis and obesity: TRIUMPH-4, 445 adults, 68 weeks (NCT05931367); TRIUMPH-1-OA, 574 adults, 80 weeks (NCT05929066)
Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial
Bellido et al. (2026). The Lancet. human humans, n=1,152, phase 3 randomised double-blind placebo-controlled trial, 80 weeks
Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity
Jastreboff et al.; TRIUMPH-1 Investigators (2026). New England Journal of Medicine. human humans, n=2,339, phase 3 randomised double-blind placebo-controlled trial, 80 weeks
Efficacy and safety of retatrutide, a GIP, GLP-1, and glucagon receptor agonist, in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1): a double-blind, randomised, phase 3 trial
Bajaj HS, Welch M, Shah P, et al. (2026). The Lancet. human humans, n=537, phase 3 randomised double-blind placebo-controlled trial (48 sites in the USA, Mexico and India)
Effects of retatrutide on body composition in people with type 2 diabetes: a substudy of a phase 2, double-blind, parallel-group, placebo-controlled, randomised trial
Coskun T, Wu Q, Schloot NC, et al. (2025). The Lancet Diabetes & Endocrinology. human adults with type 2 diabetes, phase 2 substudy, n=189 enrolled (103 with paired DXA scans)
Cagrilintide and retatrutide combination therapy enhances weight loss and metabolic outcomes in obese male rats
Petersen J, Merrild C, Holm SK, et al. (2026). Nature Metabolism. animal diet-induced obese male rats
661 Retatrutide monotherapy matches the effectiveness of anti-PD-1 immunotherapy in a preclinical model of pancreatic cancer
Marathe SJ, Bohm MS, Powell Z, et al. (2025). Journal for ImmunoTherapy of Cancer (SITC 2025 abstract supplement). animal diet-induced obese male C57BL/6J mice with implanted pancreatic tumour cells, n=10 per group

All research on Retatrutide →

Suppliers stocking Retatrutide

21 of the 49 listed suppliers. Each row opens its full listing.

American Peptides United States Products are sold for Research Use Only and not for Human Consumption. Not for human or veterinary use. Au Peptide Labs Australia For laboratory research use only. Not for human consumption. Aussie Peptides Australia Research use only. Statements have not been evaluated by the TGA. We do not ship internationally at this time. Australian Peptide Site Australia Intended for laboratory and scientific research use only. Australian Research Peptides Australia All products sold by Australian Research Peptides are supplied for in vitro research purposes only — not for human or animal consumption, and not drugs, foods, cosmetics or dietary supplements. Baltic BioLabs Lithuania For laboratory research only, not for human or veterinary use. Baltic Peptides Lithuania All products are supplied strictly for laboratory research use only. Not for human or veterinary use. British Peptide Labs United Kingdom For research use only. Not for human or veterinary use. Sold strictly for in-vitro laboratory research; not for diagnosis or treatment. CertaPeptides Romania All CertaPeptides products are sold exclusively for in-vitro laboratory research. They are not approved for human consumption, veterinary use, therapeutic applications… Dutch Peptides Netherlands Research Use Only — not for human consumption. Eurolabs Peptides Germany For research purposes only. Not for human consumption. Global Peptides Australia Unmodified peptides are sold for research use only. Nationwide Peptides United States For Research Use Only. Products are not intended for human or animal consumption, ingestion, injection, or any form of administration. Next Gen Peptides Australia Not for human consumption. Particle Peptides Slovakia Goods offered by the Company in the E-shop for purposes of scientific research and development (in vitro). Peptide Solutions Australia Australia All products are supplied strictly for research purposes only. They are not intended for human consumption, animal consumption, medical use, diagnostic use, therapeutic use. Peptides Lab UK United Kingdom Strictly intended for laboratory research use only. Not for human or veterinary consumption. Prism Labs United States All products sold by Prism Labs are intended strictly for in-vitro research, laboratory experimentation, and educational purposes. Products are not intended for human or veterinary use. Research Peptide United Kingdom Supplied strictly for research and laboratory use only and not for human or veterinary consumption. Synapse Peptides Australia Australia All products are supplied strictly for research purposes only and are not intended for human or veterinary use. Xeno Peptides United States All products are for laboratory and research use only — not for human consumption or clinical application.