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Retatrutide clinical trials: TRIUMPH and TRANSCEND tracker

Last reviewed by retainfo editorial team. How we review content.

Retatrutide is being tested in two large programmes: TRIUMPH, for obesity and its complications, and TRANSCEND, for type 2 diabetes. This page tracks all of them. Every figure links to the announcement or paper it came from.

Programme tracker

Click a column heading to sort. "Reported" means a company announcement; "Published" means a peer-reviewed paper.

Retatrutide clinical trial programme. Columns are sortable.
Registry
Phase 2 obesity (NEJM 2023)Phase 2Adults with obesity, or overweight plus a weight-related condition; no diabetes33848PublishedUp to 24.2% mean weight loss at 48 weeks (12 mg) vs 2.1% placeboNCT04881760
Phase 2a liver-fat substudy (Nature Medicine 2024)Phase 2a substudyParticipants from the Phase 2 obesity trial with MASLD and liver fat of 10% or more9848PublishedLiver fat down 82.4% at 24 weeks (12 mg); 86% reached normal liver fatNCT04881760
SYNERGY-Outcomes (MASLD master protocol)Phase 3Adults with metabolic dysfunction-associated steatotic liver disease (MASLD/MASH); includes a retatrutide arm4,500—RecruitingLiver outcomes; primary completion expected 2030NCT07165028
TRANSCEND-T2D-1Phase 3Adults with type 2 diabetes not controlled by diet and exercise alone (no other glucose-lowering drugs)53740PublishedHbA1c down 1.7 to 1.9 points vs 0.8 placebo; weight down 11.5% to 15.3% (Lancet, June 2026)NCT06354660
TRANSCEND-T2D-2Phase 3Adults with type 2 diabetes on metformin (with or without an SGLT2 inhibitor): retatrutide vs semaglutide1,250—OngoingResult pending (primary completion expected around August 2026)NCT06260722
TRANSCEND-T2D-3Phase 3Adults with type 2 diabetes and moderate or severe kidney impairment on basal insulin320—OngoingResult pending (primary completion expected around October 2026)NCT06297603
TRIUMPH-1Phase 3Adults with obesity, or overweight plus a weight-related condition; no diabetes (nested OSA and knee OA groups)2,33980Reported17.6% / 23.7% / 25.0% (4 / 9 / 12 mg) vs 3.9% placebo at 80 weeks; 30.3% at 104 weeks in the BMI 35+ extensionNCT05929066
TRIUMPH-2Phase 3Adults with type 2 diabetes and obesity or overweight1,15280Reported12.7% / 19.1% / 20.8% vs 4.0% placebo; HbA1c down up to 1.6 pointsNCT05929079
TRIUMPH-3Phase 3Adults with severe obesity and established cardiovascular disease, with or without type 2 diabetes1,94980Reported21.6% / 22.6% (9 / 12 mg) vs 3.2% placebo at 80 weeksNCT05882045
TRIUMPH-4Phase 3Adults with obesity or overweight and knee osteoarthritis44568Reported20.0% / 23.7% (9 / 12 mg) vs 4.6% placebo (treatment-regimen); up to 28.7% on the efficacy estimand; WOMAC pain down ~75%NCT05931367
TRIUMPH-5Phase 3Adults with obesity: retatrutide head-to-head against tirzepatide800—OngoingResult pending (primary completion expected around November 2026)NCT06662383
TRIUMPH-6Phase 3Adults with obesity: maintenance of weight reduction after initial loss643—OngoingResult pending (primary completion expected 2028)NCT06859268
TRIUMPH-7Phase 3Adults with obesity or overweight and chronic low back pain58680OngoingResult pending (primary completion expected September 2027)NCT07035093
TRIUMPH-8Phase 3Adults with obesity or overweight without type 2 diabetes (smaller supplementary study)250—OngoingResult pending (primary completion expected mid-2027)NCT07232719
TRIUMPH-9Phase 3Adults with obesity or overweight: comparison of different dose-escalation approaches600—OngoingResult pending (primary completion expected 2028)NCT07357415
TRIUMPH-OutcomesPhase 3 (event-driven)Adults with obesity and atherosclerotic cardiovascular disease and/or chronic kidney disease10,000—OngoingCardiovascular and kidney outcomes; primary completion expected around 2029NCT06383390

All registrations can be checked on ClinicalTrials.gov.[4]

Trial summaries

  1. 1.How to read a retatrutide trial result

    Estimands, placebo-adjusted figures, topline versus peer-reviewed, why averages hide the spread, who was excluded, and how to check a trial yourself.

  2. 2.Phase 2 trial (NEJM 2023): retatrutide's first big result

    The peer-reviewed Phase 2 retatrutide trial: 338 adults, 48 weeks, 24.2% weight loss at the top dose versus 2.1% on placebo, plus heart and liver data.

  3. 3.TRIUMPH-1: retatrutide's main obesity trial explained

    TRIUMPH-1 results in plain English: 2,339 adults, 80 weeks, 17.6% to 25.0% average weight loss versus 3.9% on placebo, side effects and drop-out rates.

  4. 4.TRIUMPH-2: retatrutide in type 2 diabetes and obesity

    TRIUMPH-2 topline: 1,152 adults with type 2 diabetes, 80 weeks, 12.7% to 20.8% weight loss versus 4.0% on placebo, HbA1c changes, side effects, drop-outs.

  5. 5.TRIUMPH-3: retatrutide in severe obesity and heart disease

    TRIUMPH-3 topline: 1,949 adults with severe obesity and heart disease, 21.6% to 22.6% weight loss versus 3.2%, and why it cannot prove fewer heart attacks.

  6. 6.TRIUMPH-4: retatrutide for obesity with knee osteoarthritis

    TRIUMPH-4, the first Phase 3 retatrutide trial to report: 445 adults, 68 weeks, both estimands, knee-pain scores, the dysesthesia signal and drop-outs.

  7. 7.TRIUMPH-5: retatrutide versus tirzepatide, result pending

    TRIUMPH-5 is the only direct trial of retatrutide against tirzepatide (Mounjaro). It has not reported. What it will and will not answer.

  8. 8.TRIUMPH-Outcomes: the heart and kidney trial, due 2029

    TRIUMPH-Outcomes will test whether retatrutide prevents heart attacks, strokes and kidney failure in 10,000 people. Why weight loss alone is not proof.

  9. 9.Retatrutide's other trials: sleep apnoea, liver, diabetes

    Beyond weight: retatrutide trials in sleep apnoea, fatty liver disease, chronic back pain and type 2 diabetes, plus the maintenance and escalation studies.

Two numbers for every result

Lilly reports each weight-loss result two ways, and news coverage often quotes the bigger one without saying so.[5]

  • The treatment-regimen estimand counts everyone who was randomised, whether or not they kept taking the drug. It is closer to "what happened to the whole group".
  • The efficacy estimand counts people while they were still taking the drug as intended. It is closer to "what the drug does if you can stay on it".

On this site the treatment-regimen figure comes first unless stated. Both are given on each trial page.

References

  1. Giblin K, Kaplan LM, Somers VK, et al. Retatrutide for the treatment of obesity, obstructive sleep apnea and knee osteoarthritis: Rationale and design of the TRIUMPH registrational clinical trials. Diabetes, Obesity and Metabolism (doi:10.1111/dom.70209), 15 October 2025. Primary source
  2. Lilly's triple agonist, retatrutide, delivered weight loss of up to an average of 71.2 lbs along with substantial relief from osteoarthritis pain in first successful Phase 3 trial (TRIUMPH-4 topline results). Eli Lilly and Company, press release, 11 December 2025. Primary source
  3. TRIUMPH-Outcomes: Cardiovascular and Kidney Outcomes Study of Retatrutide (NCT06383390). ClinicalTrials.gov, 1 January 2026. Primary source
  4. All registered retatrutide (LY3437943) studies. ClinicalTrials.gov search, 1 September 2026. Primary source
  5. Lilly's triple agonist, retatrutide, successful in two additional Phase 3 obesity trials, delivering significant improvements in weight and A1C (TRIUMPH-2 and TRIUMPH-3 topline results). Eli Lilly and Company, press release, 23 July 2026. Primary source