Overview
Retatrutide is an investigational single-molecule agonist of three receptors: incretin hormone from intestinal K cells; its receptor is a target of dual and triple agonists.">GIP, GLP-1 and glucagon. Developed by Eli Lilly, it is a fatty-acid-modified peptide with a half-life of about six days, designed to combine the appetite and insulin effects of incretin agonism with the energy-expenditure and hepatic effects attributed to glucagon-receptor activation.
A phase 2 trial published in 2023 (Jastreboff et al., NEJM) evaluated body-weight endpoints in obesity. Phase 2 studies also examined people with type 2 diabetes and substudies measured substantial reductions in liver fat. Retatrutide is being evaluated in the phase 3 TRIUMPH programme across obesity and related conditions. It is not approved by any regulator. Our product is a research-grade reference peptide for multi-receptor incretin pharmacology and is not intended for human use.
Mechanism studied
- Retatrutide
- GIPR + GLP-1R + GCGR
- Satiety & energy expenditure
- Weight & liver-fat endpoints
Retatrutide activates the incretin hormone from intestinal K cells; its receptor is a target of dual and triple agonists.">GIP receptor most potently, with lower relative activity at the glucagon and GLP-1 receptors. GLP-1 and GIP agonism enhance glucose-dependent insulin secretion and reduce appetite through central pathways. Glucagon-receptor activation, mainly in the liver, increases fatty-acid oxidation and energy expenditure and reduces hepatic lipid content, while its glucose-raising tendency is counterbalanced by the incretin components. This balance of receptor activities is the focus of current mechanistic and clinical research.
Research highlights
- 01Single peptide activating GIP, GLP-1 and glucagon receptors
- 02Phase 2 obesity trial (NEJM, 2023) evaluated body-weight endpoints over 48 weeks
- 03Large reductions in liver fat observed in phase 2 substudies
- 04Phase 3 TRIUMPH programme under way across several indications
- 05Not approved by any regulator
Research areas
- Multi-receptor incretin pharmacology
- Obesity & energy expenditure
- Hepatic fat research
- Glycaemic control models
Evidence & regulatory status
Overall status: Not approved — phase 3 clinical research
Key references
- [1]Jastreboff et al., 2023 — N Engl J Med 389:514–526
- [2]PubMed — reviews on retatrutide
Latest published research
212 papers on PubMed →Detection and Excretion Profile of Retatrutide in Human Plasma and Urine by LC-HRMS: Implications for Antidoping Analysis
Carneiro GRA et al. · Rapid communications in mass spectrometry : RCM · 2026 Dec 15 · PMID 42745421
GLP-1 receptor biology and the therapeutic role of incretin-based agonists in metabolic diseases
Koceva E et al. · European journal of pharmacology · 2026 Dec 10 · PMID 42849689
The pharmacotherapy for pediatric obesity: insights and challenges from adult weight-loss medications
Chen Z et al. · Journal of diabetes and metabolic disorders · 2026 Dec · PMID 42871568
Retatrutide-Associated Improvements in Cardiovascular Risk Biomarkers in Adults With Obesity With or Without Type 2 Diabetes
Ruotolo G et al. · Diabetes, obesity & metabolism · 2026 Nov · PMID 42608321
The First Triple Agonist for Antiobesity: Retatrutide
Tetelbaun L et al. · Cardiology in review · 2026 Nov-Dec 01 · PMID 39724554
Glucose-dependent insulinotropic polypeptide (GIP) signaling in visceral and subcutaneous adipose tissue: implications for obesity and metabolic disease-a narrative review with a structured literature search
Smarkusz-Zarzecka J et al. · Reviews in endocrine & metabolic disorders · 2026 Oct 22 · PMID 42907720
Retatrutide Once Weekly for Treatment of Obstructive Sleep Apnea
Grunstein RR et al. · The New England journal of medicine · 2026 Oct 21 · PMID 42904878
Medical treatments for obesity: what does the future have in store?
Bassatne A et al. · The Journal of clinical endocrinology and metabolism · 2026 Oct 16 · PMID 42444567
Live feed from PubMed (NCBI) for “Retatrutide”, updated 2026-10-30. Listing a paper is not an endorsement of its findings.
Registered studies
33 on ClinicalTrials.gov →- RecruitingPhase 3
A Master Protocol of Multiple Agents in Adults With Metabolic Dysfunction-Associated Steatotic Liver Disease (SYNERGY-Outcomes)
NCT07165028 · Eli Lilly and Company · 2025-10-15
- Active not recruitingPhase 3
The Effect of Retatrutide Once Weekly on Cardiovascular Outcomes and Kidney Outcomes in Adults Living With Obesity (TRIUMPH-Outcomes)
NCT06383390 · Eli Lilly and Company · 2024-04-30
- Active not recruitingPhase 1
A Study to Evaluate the Effect of Retatrutide on Insulin Secretion and Insulin Sensitivity in Adult Participants With Type 2 Diabetes Mellitus
NCT06982859 · Eli Lilly and Company · 2025-06-02
- Active not recruitingPhase 3
Effect of Retatrutide Compared With Semaglutide in Adult Participants With Type 2 Diabetes and Inadequate Glycemic Control With Metformin With or Without SGLT2 Inhibitor (TRANSCEND-T2D-2)
NCT06260722 · Eli Lilly and Company · 2024-02-21
- Active not recruitingPhase 3
A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight and Chronic Low Back Pain
NCT07035093 · Eli Lilly and Company · 2025-05-29
- CompletedPhase 3
A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight
NCT05929066 · Eli Lilly and Company · 2023-07-10
- Available
Pre-approval Expanded Access of Retatrutide (LY3437943)
NCT07629401 · Eli Lilly and Company
- CompletedPhase 3
A Study of Retatrutide (LY3437943) in Participants With Obesity and Cardiovascular Disease
NCT05882045 · Eli Lilly and Company · 2023-05-30
From the public ClinicalTrials.gov registry for “Retatrutide”, updated 2026-10-30. Shown for research context only; Purity Peptides products are not for human use.
FAQ
No. Retatrutide remains an investigational compound in phase 3 trials and has not been approved by the FDA, EMA or other regulators. Our material is a research-grade reference peptide for in-vitro and preclinical studies and must not be used in humans.
Lyophilized Retatrutide is normally kept sealed at −20 °C, protected from light and moisture. Once reconstituted for laboratory work, aliquots are held at 2–8 °C for short-term use or frozen, avoiding repeated freeze–thaw. Follow the lot-specific guidance on the certificate of analysis.
Every lot of Retatrutide ships with a certificate of analysis reporting HPLC purity, mass-spectrometry identity against the expected molecular weight, appearance and lot number. Match the COA lot to the vial label and keep it with your experimental records.
Last updated October 2026 · Reviewed by the Purity Peptides research team · Information is a summary of published literature and is not a recommendation for any use.
