Evidence brief
Retatrutide
Written and source-checked by Anthony Treviso, founder of The Peptide Field.
Direct answer
Still being studied in the United States; no FDA-approved retatrutide product.
Still being studied. Late-stage study reports show meaningful results in people, but no product is approved and no regulatory review is complete.
- How strong is the evidence?
- Emerging
Some studies in people exist. Important questions remain about benefit, safety, who it helps, or how long the effects last. This is not an approval or recommendation. - What evidence exists?
- Investigational human outcomes
Studies measured health results in people, but the molecule is still being studied and is not approved for that use. Important questions remain. - Sports rules
- Not assessed
No current sports-rule review is available.
Reviewed August 1, 2026. Sources and update notes are below.
No sales or dosing advice. This guide explains research. It was not independently medically reviewed, and it does not diagnose, prescribe, or recommend treatment.
Also known as RETA · LY3437943 · triple G agonist · triple hormone agonist
Part of Metabolic peptide medicines
Compared with Tirzepatide
Words used here
- investigational
- still being studied and not approved for that use
- outcome
- what the study measured
- molecule
- one specific chemical substance
- agonist
- a substance that activates a receptor
- phase 2
- a mid-stage study in people that checks effects and safety before larger studies
- sponsor-reported
- a result shared by the organization that sponsors the study; a full report may not be available
- clinical trial
- a planned study in people
- randomized
- assigned to study groups by chance
More detailProduct and study details
01 · Evidence profile
Four questions about the evidence
A full phase 2 report and several early phase 3 sponsor reports show meaningful results in people. Full reports for the phase 3 studies and FDA review are not complete.
Human dose-response and adverse-event data exist, but the development program is not complete.
Phase 2 exposure cannot define the full safety profile, rare risks, or long-term benefit-risk balance.
High for controlled clinical-trial material; low for products sold outside those trials.
02 · Identity
What it is
Retatrutide is an investigational molecule that acts on three body-signal receptors: GIP, GLP-1, and glucagon. It is not the same molecule as semaglutide or tirzepatide, and it is not an FDA-approved medicine.
Scientific group: GIP, GLP-1, and glucagon receptor agonist. This group name describes the type of molecule or body signal. It does not prove a benefit, safety, or approval.
03 · Exact product
The molecule is not the finished product.
Formulation: The finished product's ingredients and physical form. Route: How the product enters the body. Indication: The approved or studied use and group of people for a product.
None identified in the United States.
- Investigational obesity and metabolic-disease programs
04 · Research results
What the research shows
In a 48-week phase 2 study, people were assigned to groups by chance. Higher study doses were linked to more weight reduction. Lilly announced early sponsor-reported TRIUMPH-1 results in May 2026. It announced early sponsor-reported TRIUMPH-2 and TRIUMPH-3 results in July 2026. These studies covered specific groups of people with obesity. Some groups had type 2 diabetes or established cardiovascular disease, and some did not.
These announcements are early summaries from the study sponsor. They do not replace full reports checked by other experts or FDA review. Retatrutide is still being studied, and other outcome programs remain active. Current records do not show its long-term balance of possible benefits and harms, rare harms, broad real-world effectiveness, or whether products sold outside clinical trials have the same identity.
Exact product
A product sold under the same name may not match the product used in trials. Retatrutide is still being studied. A study product made under a study protocol does not prove that products sold online under the same name have the same identity or quality.
05 · Claim check
Claims I checked
6 claims checked for this brief.
“Retatrutide caused weight loss in a randomized human trial.”
The phase 2 trial reported dose-dependent weight reduction over 48 weeks in a defined adult population.
- Evidence used
- Randomized human outcomes. This answer uses a study that assigned people to groups by chance and measured a health outcome.
- Limits of this answer
- Adults meeting the phase 2 obesity-trial criteria over 48 weeks. This answer covers only the named molecule and finished product. It also covers the product form and how people used it. The study limits include who took part, what was used for comparison, what changed, and how long the study lasted.
“Retatrutide is FDA-approved.”
It remains investigational. FDA says retatrutide is not a component of an approved drug and has not been found safe and effective for any condition. Positive trial results and sponsor announcements are not marketing approval.
- Evidence used
- Regulatory or product record. This answer uses an official regulator record or a specific product label.
- Limits of this answer
- United States regulatory status as reviewed August 1, 2026. This answer covers only the named molecule and finished product. It also covers the product form and how people used it. The study limits include who took part, what was used for comparison, what changed, and how long the study lasted.
“Phase 3 trials showed retatrutide produced average weight reduction above 20%.”
Lilly reported average weight reduction of up to 20.8% in TRIUMPH-2 and up to 22.6% in TRIUMPH-3 at 80 weeks. These are sponsor-reported topline efficacy-estimand figures and group averages, not individual outcomes, and no full peer-reviewed report of either trial was available in the records reviewed here.
- Evidence used
- Sponsor-reported trial results. This answer uses a trial result reported by the study sponsor. A full report checked by other experts may not be available yet.
- Limits of this answer
- Adults meeting the TRIUMPH-2 (obesity or overweight with type 2 diabetes) and TRIUMPH-3 (severe obesity with established cardiovascular disease) entry criteria at 80 weeks, as disclosed by Lilly in July 2026. This answer covers only the named molecule and finished product. It also covers the product form and how people used it. The study limits include who took part, what was used for comparison, what changed, and how long the study lasted.
Show 3 more claim checks
“The TRIUMPH-3 results show retatrutide prevents cardiovascular events.”
TRIUMPH-3 was not a definitive cardiovascular-outcomes trial. The sponsor reported a hazard ratio of 0.82 (95% CI 0.55 to 1.22) for the five-component major adverse cardiovascular event measure and 1.12 (95% CI 0.64 to 1.96) for the three-component measure. Both intervals include 1.0 and are wide, so studying a molecule in people with cardiovascular disease is not the same as showing it prevents events.
- Evidence used
- Sponsor-reported trial results. This answer uses a trial result reported by the study sponsor. A full report checked by other experts may not be available yet.
- Limits of this answer
- The TRIUMPH-3 cardiovascular-event analyses as disclosed by Lilly in July 2026, pending a full report. This answer covers only the named molecule and finished product. It also covers the product form and how people used it. The study limits include who took part, what was used for comparison, what changed, and how long the study lasted.
“Retatrutide is being submitted to FDA, so it will be available in 2027.”
Lilly states it plans to submit retatrutide for obesity in the first quarter of 2027. A planned submission is a future corporate action, not regulatory acceptance, approval, a prescribing label, or a launch date. Until an approval is recorded by the regulator, the accurate U.S. status remains investigational.
- Evidence used
- Regulatory or product record. This answer uses an official regulator record or a specific product label.
- Limits of this answer
- The sponsor-stated first-quarter 2027 U.S. submission plan as reviewed August 1, 2026. This answer covers only the named molecule and finished product. It also covers the product form and how people used it. The study limits include who took part, what was used for comparison, what changed, and how long the study lasted.
“Research retatrutide sold online is the same as clinical-trial material.”
A matching label name does not establish sequence, purity, sterility, formulation, storage, or clinical equivalence. FDA warns that retatrutide products sold directly to consumers as research material are unapproved and of unknown quality.
- Evidence used
- No reliable human outcome evidence. No reliable study in people shows the health outcome in this statement.
- Limits of this answer
- Products outside an authorized clinical-development supply chain. This answer covers only the named molecule and finished product. It also covers the product form and how people used it. The study limits include who took part, what was used for comparison, what changed, and how long the study lasted.
06 · Questions
Questions people ask about Retatrutide
Still being studied in the United States; no FDA-approved retatrutide product. No approved product is identified in the United States.
Not assessed. This editorial review did not determine sport eligibility. Athletes must check the current prohibited list, Global DRO, and their governing body. This status is not personal clearance to compete.
In a 48-week phase 2 study, people were assigned to groups by chance. Higher study doses were linked to more weight reduction. Lilly announced early sponsor-reported TRIUMPH-1 results in May 2026. It announced early sponsor-reported TRIUMPH-2 and TRIUMPH-3 results in July 2026. These studies covered specific groups of people with obesity. Some groups had type 2 diabetes or established cardiovascular disease, and some did not.
These announcements are early summaries from the study sponsor. They do not replace full reports checked by other experts or FDA review. Retatrutide is still being studied, and other outcome programs remain active. Current records do not show its long-term balance of possible benefits and harms, rare harms, broad real-world effectiveness, or whether products sold outside clinical trials have the same identity.
07 · Safety
Safety limits for this record
An investigational molecule is not a self-treatment category. This guide does not provide trial-drug access, sourcing, dosing, injection, or combination instructions.
This editorial review did not determine sport eligibility. Athletes must check the current prohibited list, Global DRO, and their governing body.
No current sports-rule review is available.
Reviewed .Check current rules for tested sport ↗08 · Sources
Read the sources
09 · Review history
Review history
Revalidated FDA approval status, the boundary between trial material and online products, and the distinction between a planned 2027 submission and approval or availability.
Registered the Phase 3 and submission-plan statements as scoped claim records and split the TRIUMPH-1 and TRIUMPH-2/3 disclosure dates. No new evidence was reviewed.
Added Lilly's July 2026 early sponsor-reported Phase 3 results. Rechecked that retatrutide remained under study and not FDA-approved. Also checked the limits for products sold under its name.
Checked against the phase 2 publication and the June 2026 TRIUMPH-1 registry update: study complete, no summary results posted.
Written and source-checked by Anthony Treviso, founder of The Peptide Field.
Not independently medically reviewed. This page is not a dosing, sourcing, or treatment guide.