# Retatrutide Retatrutide (LY3437943) is an experimental Eli Lilly peptide described in the published literature as acting on three receptor systems at once. This hub collects the questions people ask about it and answers each one from the trial record. | | | | --- | --- | | Common name | retatrutide | | Research code | LY3437943 | | Developer | Eli Lilly | | CAS | 2381089-83-2 | | Discovery year | 2022 | | Trial phase as of 2026 | Phase 3 | | Approval as of 2026 | Approved in no country | Start with the question you came with. Each guide below answers one question from published trial papers, trial registries and regulator records, and names its sources and check date. Three related guides sit outside this hub: [retatrutide research records in Perth](/learn/peptides-perth/retatrutide-perth), [the status of the TRIUMPH-OUTCOMES trial](/learn/peptides-and-australian-law/retatrutide-triumph-outcomes-status) and [how peptides are regulated and verified in Australia](/learn/peptides-in-australia). [Form Laboratories](/) supplies research-use-only reference material from Perth. This hub is education about the published record. It is not medical advice and not a use instruction. ## Articles in this hub - [Retatrutide vs Mounjaro vs Ozempic: what's the difference?](https://www.formlaboratories.com/learn/retatrutide/retatrutide-vs-mounjaro-vs-ozempic) - Retatrutide, Mounjaro, and Ozempic compared by molecule, receptor systems, and approval status. Research material is not a medicine. - [What is the difference between GLP-1 and GLP-3?](https://www.formlaboratories.com/learn/retatrutide/what-glp-1-and-glp-3-mean) - GLP-1 is a natural gut hormone. GLP-3 is a nickname. Learn what GLP-1, GIP and glucagon receptors mean, and what names alone cannot show. - [Is retatrutide available in the USA? What the public record says](https://www.formlaboratories.com/learn/retatrutide/retatrutide-united-states-approval-record) - Retatrutide's US approval record, checked 17 October 2026. Read FDA statements and Lilly's filing plan. A trial listing does not mean medicine approval. - [How much does retatrutide cost? Is there an approved price?](https://www.formlaboratories.com/learn/retatrutide/is-there-an-approved-retatrutide-price) - The checked records give no price for retatrutide as an approved medicine. Learn what approval, a maker's price and a PBS listing each mean. - [What does retatrutide do in the body? The three receptors in the papers](https://www.formlaboratories.com/learn/retatrutide/which-receptors-the-papers-name) - Retatrutide papers name three cell receivers: GIP, GLP-1 and glucagon receptors. Learn what cell tests and human trials measure, and what each cannot show. - [How are people getting retatrutide? Trials, approval and research supply](https://www.formlaboratories.com/learn/retatrutide/how-people-access-retatrutide) - What trial records and medicine checks say about retatrutide access and research-only labels. Dated facts, without buying or personal-use advice. - [Who should not take retatrutide? What the trial exclusion lists say](https://www.formlaboratories.com/learn/retatrutide/who-was-excluded-from-retatrutide-trials) - Who was left out of retatrutide trials? Read how TRIUMPH entry rules differ and why these lists cannot show personal safety. - [What makes a peptide company reputable? How to check a supplier's testing](https://www.formlaboratories.com/learn/retatrutide/what-makes-a-peptide-company-reputable) - Check a peptide supplier's batch records and test reports. Learn what purity tests, mass tests and outside labs can show. - [What is replacing tirzepatide? Weight-loss medicines in Phase 3 in 2026](https://www.formlaboratories.com/learn/retatrutide/what-is-replacing-tirzepatide) - A dated look at retatrutide, CagriSema, survodutide and VK2735. Read about their targets, Phase 3 studies and what the records cannot show. - [Retatrutide and type 2 diabetes: what the trials measured](https://www.formlaboratories.com/learn/retatrutide/retatrutide-type-2-diabetes-trials) - What retatrutide diabetes trials measured. Read about HbA1c, the Lancet Phase 2 paper and TRANSCEND-T2D study plans. Check dated study records and limits. - [How long has retatrutide been studied?](https://www.formlaboratories.com/learn/retatrutide/how-long-has-retatrutide-been-studied) - Retatrutide's research record from the first dated human enrollment in December 2019 to Phase 3 in 2026. Research material is not a medicine. - [Retatrutide pharmacokinetics: what is the half-life?](https://www.formlaboratories.com/learn/retatrutide/retatrutide-pharmacokinetics) - Retatrutide's pharmacokinetics as published in two early human studies, what each study enrolled and measured, and what has not been measured. Research material is not a medicine. - [Retatrutide Phase 2 trial: what did the paper find?](https://www.formlaboratories.com/learn/retatrutide/retatrutide-phase-2-nejm-2023) - A guided read of the retatrutide Phase 2 obesity trial (NEJM 2023): 338 adults, 48 weeks, and what the primary end point actually measured. - [What is the molecular formula of retatrutide?](https://www.formlaboratories.com/learn/retatrutide/retatrutide-molecular-formula) - Retatrutide molecular formula: C221H342N46O68, the registry record it comes from, and what a count of atoms cannot prove. Research use only. - [NCT05882045: what is the TRIUMPH-3 retatrutide trial?](https://www.formlaboratories.com/learn/retatrutide/nct05882045) - NCT05882045 is TRIUMPH-3, a Phase 3 retatrutide trial in obesity with cardiovascular disease. Registry status, enrolment, endpoint, and no posted results. - [NCT05929066: what is the TRIUMPH-1 retatrutide trial?](https://www.formlaboratories.com/learn/retatrutide/nct05929066) - NCT05929066 is TRIUMPH-1, a Phase 3 retatrutide trial in obesity without type 2 diabetes. Registry status, enrolment, nested sub-studies, no posted results. - [Where does tirzepatide come from? Lilly's LY3298176](https://www.formlaboratories.com/learn/retatrutide/where-does-tirzepatide-come-from) - Tirzepatide began as Eli Lilly's LY3298176, a synthetic 39-amino-acid peptide engineered on a GIP backbone. Whether it is a peptide or a hormone, and how it differs from semaglutide. - [SURPASS and SURMOUNT: what the tirzepatide trials measured](https://www.formlaboratories.com/learn/retatrutide/surpass-and-surmount) - SURPASS trials measured HbA1c in type 2 diabetes. SURMOUNT trials measured body weight. Two named tirzepatide programmes, two different questions. - [Retatrutide in Australia: is it legal, approved or available yet?](https://www.formlaboratories.com/learn/retatrutide/is-retatrutide-legal-in-australia) - Retatrutide's approval and legal status in Australia and the US as of 14 October 2026: TGA statements, the Poisons Standard, the WADA list, the developer's submission plan, trial records and what is still unknown. - [Retatrutide study findings: what do the clinical trials show?](https://www.formlaboratories.com/learn/retatrutide/retatrutide-study-findings) - What published retatrutide trials found on weight, body fat, appetite and side effects, which registered trials are running in Australia, and what the studies do not show. - [Retatrutide side effects: what trials and regulators have recorded](https://www.formlaboratories.com/learn/retatrutide/retatrutide-side-effects) - The side effects recorded in retatrutide trials, how often they occurred against placebo, serious events, and what Australian authorities have reported about products sold as retatrutide. --- Canonical page: https://www.formlaboratories.com/learn/retatrutide Form Laboratories - Perth-based research-use-only peptide supplier, shipping Australia-wide. - Site guide for agents: https://www.formlaboratories.com/llms.txt - Sitemap: https://www.formlaboratories.com/sitemap.xml - Full catalogue: https://www.formlaboratories.com/shop - Contact: hello@formlaboratories.com All materials are supplied for laboratory research use only - not for human or veterinary use, and nothing on this site is medical advice.