Retatrutide Phase 3 Programme

Overview of the Phase 3 Programme

Retatrutide (development code LY3437943) is an investigational triple agonist targeting the glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon receptors. Sponsored and developed by Eli Lilly and Company, retatrutide is currently being investigated across multiple Phase 3 clinical studies. These Phase 3 trials are structured primarily under two broad clinical trial families: the TRIUMPH programme, which focuses on obesity, overweight, cardiovascular outcomes, and obesity-related comorbidities, and the TRANSCEND programme, which evaluates the compound in type 2 diabetes mellitus.

Retatrutide is strictly an investigational candidate. It is not approved by the U.S. Food and Drug Administration (FDA) or any other regulatory agency, and its safety and efficacy have not been formally established. Readers can review overall development tracking on the Clinical Trial Tracker and regulatory context on the FDA Approval Tracker.

Phase 3 Clinical Trial Directory

The following table summarizes the Phase 3 clinical trials evaluating retatrutide, including trial identifiers, recruitment status, target indications, and total planned enrolment.

The TRIUMPH Clinical Programme (Obesity and Comorbidities)

The TRIUMPH clinical programme consists of multiple randomized, controlled studies designed to evaluate retatrutide in broad and comorbid populations with obesity or overweight.

Cardiovascular and Renal Outcomes (TRIUMPH-Outcomes)

• Identifier: NCT06383390
• Comparator: Placebo
• Study Start: 2024-04-30
• Primary Completion: 2029-02-01
• Primary Endpoints: Time to First Occurrence of Composite Endpoints; Time to First Occurrence of Composite Endpoint of End Stage Kidney Disease (ESKD), ≥ 40% Sustained Decline in Estimated Glomerular Filtration Rate (eGFR), CV Death or Renal Death.

TRIUMPH-Outcomes is the largest study in the Phase 3 pipeline with an enrolment of 10,000 participants living with obesity, atherosclerotic cardiovascular disease, and chronic kidney disease.

General Obesity and Comorbidity Trials

• TRIUMPH-1 (NCT05929066): Enrolled 2,335 participants with obesity, overweight, knee osteoarthritis, or obstructive sleep apnea. The study started on 2023-07-10 with a primary completion date of 2026-04-06. The primary endpoints include Percent Change From Baseline in Body Weight, Change from Baseline in Apnea-Hypopnea Index (AHI) Events Per Hour for the GSA1 subset, Change from Baseline in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale Score for the GOA1 subset, and Percent Change from Baseline in Body Weight in participants in the extension subset. The trial status is completed.
• TRIUMPH-4 (NCT05931367): Enrolled 445 participants to examine retatrutide against placebo in individuals with obesity or overweight and knee osteoarthritis. Study start was 2023-08-01 and primary completion was 2025-11-14. Primary endpoints are Change from Baseline in the WOMAC Pain Subscale Score and Percent Change from Baseline in Body Weight. The trial status is completed.
• TRIUMPH-5 (NCT06662383): An active, not recruiting study enrolling 800 participants with obesity. This trial evaluates retatrutide against an active comparator, tirzepatide. The study start date was 2024-11-01 and the primary completion date is 2026-11-01. The primary endpoint is Percent Change from Baseline in Body Weight.
• TRIUMPH-7 (NCT07035093): Evaluates retatrutide against placebo in 586 individuals with obesity, overweight, and chronic low back pain (CLBP). Initiated on 2025-05-29 with primary completion targeted for 2027-09-01, its primary endpoints are Change from Baseline in Pain Intensity Per Numeric Rating Scale and Percent Change from Baseline in Body Weight.
• TRIUMPH-9 (NCT07357415): Enrolled 600 participants with obesity or overweight. Initiated on 2026-01-24 with primary completion scheduled for 2028-10-01, the primary endpoint is Percent Change from Baseline in Body Weight.

The TRANSCEND Clinical Programme (Type 2 Diabetes)

The TRANSCEND programme evaluates retatrutide specifically in individuals with type 2 diabetes mellitus.

• TRANSCEND-T2D-1 (NCT06354660): Enrolled 537 participants with type 2 diabetes and inadequate glycemic control managed with diet and exercise alone. Retatrutide was evaluated against placebo. The study started on 2024-04-10, had a primary completion date of 2026-01-22, and is marked completed. The primary endpoint is Change from Baseline in Hemoglobin A1c (HbA1c) (%).
• TRANSCEND-T2D-2 (NCT06260722): An active, not recruiting study enrolling 1,250 participants with type 2 diabetes with inadequate glycemic control on metformin with or without an SGLT2 inhibitor. This trial evaluates retatrutide against an active comparator, semaglutide. Study start was 2024-02-21, with primary completion expected by 2026-08-01. The primary endpoint is Change from Baseline in Hemoglobin A1c (HbA1c) (%).

Data Availability and Pipeline Updates

Sources

• ClinicalTrials.gov Record NCT06383390 (TRIUMPH-Outcomes)
• ClinicalTrials.gov Record NCT05929066 (TRIUMPH-1)
• ClinicalTrials.gov Record NCT05931367 (TRIUMPH-4)
• ClinicalTrials.gov Record NCT06662383 (TRIUMPH-5)
• ClinicalTrials.gov Record NCT07035093 (TRIUMPH-7)
• ClinicalTrials.gov Record NCT07357415 (TRIUMPH-9)
• ClinicalTrials.gov Record NCT06354660 (TRANSCEND-T2D-1)
• ClinicalTrials.gov Record NCT06260722 (TRANSCEND-T2D-2)
• Eli Lilly and Company Regulatory and Financial Announcements (July 2026, August 2026)