--- title: "Retatrutide: What It Is, Evidence and Legal Status (2026)" description: "Retatrutide: triple-agonist weight-loss drug in late-stage trials. Evidence grade A. US status as of Oct 17, 2026: investigational. No dosing, no sellers." canonical: https://plainlygraded.com/peptides/retatrutide/ last_updated: 2026-10-17 breadcrumb: "Home > Compounds > Retatrutide" publisher: Plainly Graded policy: "No dosing, no sourcing, no vendor links. Every claim cites a public source." --- > We collect and compare information from public, cited sources. We cannot guarantee that it is complete, current or correct. This is not medical advice. Only a doctor can prescribe, and a doctor should confirm anything you read here before you act on it. # Retatrutide Also called "reta", "GLP-3", "LY3437943" - [FDA: investigational](https://plainlygraded.com/regulatory/#retatrutide) - [WADA: not named, ask USADA](https://plainlygraded.com/regulatory/#retatrutide) STATUS AS OF 17 OCT 2026 FDA: not FDA-approved and not yet filed; Lilly says it plans to submit in early 2027 · WADA: gLP-1 agonists are not prohibited, but retatrutide is unapproved, so section S0 may apply until approval; ask USADA · [tracker entry](https://plainlygraded.com/regulatory/#retatrutide) **The short answer:** Retatrutide is an investigational weight-loss drug from Eli Lilly that acts on three hormone receptors (GIP, GLP-1 and glucagon). As of October 17, 2026 it is not FDA-approved; the TRIUMPH-1 trial of 2,339 adults was published in NEJM in September 2026, and Lilly says it plans to file in early 2027. Written by [Maren Holt](https://plainlygraded.com/about/team/) 5 PUBLIC SOURCES · UPDATED 17 OCT 2026 · NO TIES TO SELLERS [How we source](https://plainlygraded.com/how-we-source/) ## What is Retatrutide? Retatrutide is a single molecule that activates three receptors: GIP, GLP-1 and glucagon. Semaglutide acts on one of these and tirzepatide on two, which is why people online call retatrutide "GLP-3". It is made by Eli Lilly and is still in trials. Products sold online as retatrutide are not Lilly's drug; in August 2026 FDA sent warning letters to online sellers whose products included retatrutide. ## What is Retatrutide claimed to do, and what does the evidence show? **Overall grade** **Evidence grade A** **Strongest evidence** Phase 3 trial (TRIUMPH-1, 2,339 adults) GRADE A: CONSISTENT RANDOMIZED CONTROLLED TRIALS IN PEOPLE, FOR THIS USE · [HOW WE GRADE](https://plainlygraded.com/evidence-grading/) | Use | Claimed | Shown | Grade | | --- | --- | --- | --- | | Weight loss | More weight loss than current drugs | In TRIUMPH-1 (2,339 adults, 80 weeks), mean weight change in the highest-dose arm was about -25%, against -3.9% on placebo. No head-to-head trial against tirzepatide has reported yet.[4] | **Evidence grade A** | ## What are the known risks and side effects of Retatrutide? In TRIUMPH-1 the most common side effects were mild to moderate stomach and gut problems. Symptoms of low blood pressure were dose-dependent and more common in people taking blood-pressure medicines. An unapproved product has no required quality testing. In July 2026 FDA staff told the agency's advisers they had concerns about impurities, bacterial toxins and unreliable certificates for several of these peptides, and that nobody knows how often they trigger an immune response. Who should be especially careful - **People with a history of eating disorders.** Weight-loss drugs can make disordered eating harder to manage. NEDA and 988 can help. - **People taking blood-pressure medicines.** Low-blood-pressure symptoms were more common in this group in TRIUMPH-1. - **People who are pregnant, trying to get pregnant or breastfeeding.** There is no human data in pregnancy. - **Anyone under 18.** It has not been studied in young people. Get medical help now if you have - Swelling of the face, lips or throat, trouble breathing, chest pain, a racing heart or fainting. **Call 911.** - Redness spreading from an injection site, warmth, pus or a fever. Get same-day care. - Severe stomach pain that won't go away, with or without vomiting. Get same-day care. - Unsure what you took or whether a reaction is serious: **Poison Control 1-800-222-1222** (free, 24 hours). - Thoughts of harming yourself: call or text **988**. If food, weight or exercise feels out of control You are not alone. Talk to someone at the [NEDA](https://www.nationaleatingdisorders.org/) helpline, or call or text 988. ## Is Retatrutide legal? Not FDA-approved and not yet filed; Lilly says it plans to submit in early 2027.[1] - **29 SEP 2026:** TRIUMPH-1 full results published in NEJM.[4] - **24 AUG 2026:** FDA warning letters to five online sellers named products that included retatrutide.[2] - **23 JUL 2026:** Lilly said it plans to submit retatrutide to FDA in early 2027.[1] Every status change for Retatrutide is logged with its date and source in the [regulatory tracker entry for Retatrutide](https://plainlygraded.com/regulatory/#retatrutide). ## Is Retatrutide banned in sport? GLP-1 agonists are not prohibited, but retatrutide is unapproved, so section S0 may apply until approval; ask USADA.[3,5] Anti-doping rules work on strict liability: a positive test counts whatever the label said. ## What don't we know about Retatrutide? Still unknown - Long-term effects beyond the trial period. - How it compares directly with tirzepatide: no head-to-head result has been published. - What is in products sold online as retatrutide. Why this page has no dosing We don't publish doses, schedules or mixing instructions for Retatrutide or any unapproved peptide. No human dose has been established for most of these uses, so we list what to ask a licensed prescriber instead. [Here's why, and who can legally answer](https://plainlygraded.com/why-we-dont-give-dosing/) ## What should you tell your doctor if you're using Retatrutide? Tell them exactly what you took, for how long, and where it came from, and bring the label. These questions can help the conversation: - Is there an approved treatment for my goal that has been tested in people? - What should I watch for, and which symptoms mean I should stop and call you? - Could it interact with the medicines I already take? ### Compare next - [Tirzepatide](https://plainlygraded.com/peptides/tirzepatide/) **Sources** 1. Eli Lilly and Company. TRIUMPH-2 and TRIUMPH-3 topline results; plan to submit to FDA in early 2027, 2026-07-23. 2. US Food and Drug Administration. Warning letters to five online peptide sellers, August 24, 2026, 2026-08-24. 3. World Anti-Doping Agency. [2026 Prohibited List (sections S0 and S2)](https://www.wada-ama.org/en/prohibited-list), 2026-01-01. 4. New England Journal of Medicine. Retatrutide for obesity: TRIUMPH-1 (Jastreboff et al.), 2026-09-29. 5. World Rugby. [WADA publishes 2027 Prohibited List (GLP-1 agonists unchanged)](https://www.world.rugby/keep-rugby-clean/news/1048285/wada-publishes-2027-prohibited-list), 2026-10-06. (news report) **Changelog** 17 OCT 2026 Draft. Statuses read from the regulatory record dated 2026-10-17. Spotted an error? [Report it](https://plainlygraded.com/corrections/). We never change a page's updated date without changing its content. --- We collect and compare information from public, cited sources. We cannot guarantee that it is complete, current or correct. This is not medical advice. Only a doctor can prescribe, and a doctor should confirm anything you read here before you act on it. Canonical page: https://plainlygraded.com/peptides/retatrutide/