Study tracker · Weight · Metabolism

Retatrutide

Updated 19 Oct 2026 · Peptilex evidence grade B (A = approved, large trials · D = mainly animal studies)

Phase 3 is delivering: in TRIUMPH-1 (NEJM, 2026) adults with obesity lost 25% of their body weight on average over 80 weeks in the highest-level group, versus about 4% on placebo. A 10,000-person heart and kidney outcomes trial is running, and the manufacturer plans to file for approval in 2027.

207PubMed papers

125Human studies

10Randomized trials

32Registered studies

10Ongoing / starting

13Phase 3+

Registered trials

From ClinicalTrials.gov, matched by name in the study title.

Study	Phase	Status	Participants	Start
The Effect of Retatrutide Once Weekly on Cardiovascular Outcomes and Kidney Outcomes in Adults Living With Obesity (TRIUMPH-Outcomes) NCT06383390 · Eli Lilly and Company	Phase 3	Running	10,000	2024-04
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	Phase 3	Running	1,250	2024-02
A Study of Retatrutide (LY3437943) Compared to Tirzepatide (LY3298176) in Adults Who Have Obesity NCT06662383 · Eli Lilly and Company	Phase 3	Running	800	2024-11
A Study of Retatrutide (LY3437943) in the Maintenance of Weight Reduction in Individuals With Obesity NCT06859268 · Eli Lilly and Company	Phase 3	Running	643	2025-03
A Study of Retatrutide (LY3437943) in Participants Without Type 2 Diabetes Who Have Obesity or Overweight NCT07357415 · Eli Lilly and Company	Phase 3	Running	600	2026-01
A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight and Chronic Low Back Pain NCT07035093 · Eli Lilly and Company	Phase 3	Running	586	2025-05
Effect of Retatrutide Compared With Placebo in Participants With Type 2 Diabetes and Moderate or Severe Renal Impairment, With Inadequate Glycemic Control on Basal Insulin, With or Without Metformin and/or SGLT2 Inhibitor (TRANSCEND-T2D-3) NCT06297603 · Eli Lilly and Company	Phase 3	Running	320	2024-03
A Study of Retatrutide (LY3437943) in Participants With Obesity or Overweight NCT07232719 · Eli Lilly and Company	Phase 3	Running	250	2025-11
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	Phase 1	Running	95	2025-06
Pre-approval Expanded Access of Retatrutide (LY3437943) NCT07629401 · Eli Lilly and Company	Expanded access	Expanded access	–
A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight NCT05929066 · Eli Lilly and Company	Phase 3	Completed	2,335	2023-07
A Study of Retatrutide (LY3437943) in Participants With Obesity and Cardiovascular Disease NCT05882045 · Eli Lilly and Company	Phase 3	Completed	1,946	2023-05
A Study of Retatrutide (LY3437943) in Participants With Type 2 Diabetes Mellitus Who Have Obesity or Overweight NCT05929079 · Eli Lilly and Company	Phase 3	Completed	1,152	2023-07
Effect of Retatrutide Compared With Placebo in Adult Participants With Type 2 Diabetes and Inadequate Glycemic Control With Diet and Exercise Alone (TRANSCEND-T2D-1) NCT06354660 · Eli Lilly and Company	Phase 3	Completed	537	2024-04
A Study of Retatrutide (LY3437943) Once Weekly in Participants Who Have Obesity or Overweight and Osteoarthritis of the Knee NCT05931367 · Eli Lilly and Company	Phase 3	Completed	445	2023-08
A Study of LY3437943 in Participants Who Have Obesity or Are Overweight NCT04881760 · Eli Lilly and Company	Phase 2	Completed	338	2021-05
A Study of LY3437943 in Participants With Type 2 Diabetes NCT04867785 · Eli Lilly and Company	Phase 2	Completed	281	2021-05
A Study of Retatrutide (LY3437943) on Renal Function in Participants With Overweight or Obesity and Chronic Kidney Disease With or Without Type 2 Diabetes NCT05936151 · Eli Lilly and Company	Phase 2	Completed	146	2023-07
A Study to Measure Calorie Consumption and Usage in Participants With Obesity Using LY3437943 NCT06313528 · Eli Lilly and Company	Phase 1	Completed	85	2024-03
A Study of LY3437943 in Healthy Participants With a High Body Mass Index NCT05959096 · Eli Lilly and Company	Phase 1	Completed	85	2023-07
A Study to Investigate the Response of Participants With Type 2 Diabetes Mellitus on Once-Weekly Retatrutide to Hypoglycemia NCT06982846 · Eli Lilly and Company	Phase 1	Completed	80	2025-06
A Study of LY3437943 in Participants With Type 2 Diabetes Mellitus (T2DM) NCT04143802 · Eli Lilly and Company	Phase 1	Completed	72	2019-12
A Study of LY3437943 in Japanese Participants With Type 2 Diabetes Mellitus (T2DM) NCT04823208 · Eli Lilly and Company	Phase 1	Completed	64	2021-05
A Research Study Looking at Similarity Between LY3437943 Versions for Different Injection Devices NCT06003465 · Eli Lilly and Company	Phase 1	Completed	57	2023-08
A Study of LY3437943 in Postmenopausal Female Participants Who Are Overweight or Obese NCT06039826 · Eli Lilly and Company	Phase 1	Completed	46	2023-09

1 further registry entry from a sponsor we could not verify is not listed.

Showing 25 of 32 matching registered studies (ongoing first). See all on ClinicalTrials.gov.

Latest randomized trials & key papers

From PubMed. The full story – mechanism, all results, risks – is in the Retatrutide profile of the book.

2026Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity
Jastreboff AM et al. · The New England journal of medicine · PMID 42814954
2026Retatrutide-Associated Improvements in Cardiovascular Risk Biomarkers in Adults With Obesity With or Without Type 2 Diabetes
Ruotolo G et al. · Diabetes, obesity & metabolism · PMID 42608321
2026UBT251, a novel triple GLP-1, GIP, and glucagon receptor agonist, in adults with overweight or obesity: A multicenter, randomized phase 2 trial
Zhou Z et al. · Cell metabolism · PMID 42843337
2026Efficacy and safety of retatrutide, a GIP, GLP-1, and glucagon receptor agonist, in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1): a double-blind, randomised, phase 3 trial
Bajaj HS et al. · Lancet (London, England) · PMID 42250575
2026Retatrutide and lipid and metabolite profiles in participants with obesity with or without type 2 diabetes
Pearson MJ et al. · The Journal of clinical endocrinology and metabolism · PMID 42135195
2026Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial
Bellido V et al. · Lancet (London, England) · PMID 42810372
2026Comparative effects of drugs for adults with overweight or obesity: systematic review and network meta-analysis
Nong K et al. · BMJ (Clinical research ed.) · PMID 42419792
2025Effects of retatrutide on body composition in people with type 2 diabetes: a substudy of a phase 2, double-blind, parallel-group, placebo-controlled, randomised trial
Coskun T et al. · The lancet. Diabetes & endocrinology · PMID 40609566

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