A Study of Retatrutide (LY3437943) in Participants With Obesity or Overweight
TRIUMPH-8
A Phase 3b Study to Investigate the Efficacy and Safety of Retatrutide Once Weekly in Participants Without Type 2 Diabetes Who Have Obesity or Overweight: A Randomized, Double-Blind, Placebo-Controlled Trial
2 other identifiers
interventional
250
2 countries
31
Brief Summary
The purpose of this study is to evaluate the efficacy and safety of retatrutide compared with placebo for body weight reduction. Participation in the study will last about 65 weeks and may include about 18 visits.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for phase_3 obesity
Started Nov 2025
31 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
November 14, 2025
CompletedStudy Start
First participant enrolled
November 17, 2025
CompletedFirst Posted
Study publicly available on registry
November 18, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
July 1, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
July 1, 2027
April 17, 2026
April 1, 2026
1.6 years
November 14, 2025
April 16, 2026
Conditions
Outcome Measures
Primary Outcomes (1)
Percent Change from Baseline in Body Weight
Baseline, Week 56
Secondary Outcomes (4)
Change from Baseline in Systolic Blood Pressure
Baseline, Week 56
Change from Baseline in Waist Circumference
Baseline, Week 56
Percent Change from Baseline in Non-High-Density Lipoprotein (HDL) Cholesterol
Baseline, Week 56
Pharmacokinetics (PK): Steady State Area Under the Concentration Time Curve (AUC)
Baseline through Week 56
Study Arms (3)
Retatrutide Dose 1
EXPERIMENTALParticipants will receive retatrutide subcutaneously (SC)
Retatrutide Dose 2
EXPERIMENTALParticipants will receive retatrutide SC
Placebo
PLACEBO COMPARATORParticipants will receive placebo SC
Interventions
Eligibility Criteria
You may qualify if:
- Have a body mass index (BMI) of:
- ≥30 kilogram per square meter (kg/m2) OR
- ≥27 kg/m2 with at least one of the following weight-related conditions: high blood pressure, abnormal levels of lipid, obstructive sleep apnea, heart disease
- Have at least one unsuccessful attempt to lose weight by dieting
You may not qualify if:
- Have a self-reported change in body weight \>5 kg (11 pounds) within 90 days before screening
- Have a prior or planned surgical treatment for obesity
- Have type 1 diabetes or type 2 diabetes
- Have a family or personal history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 (MEN-2)
- Have had within the past 90 days before screening
- acute myocardial infarction
- cerebrovascular accident (stroke)
- hospitalization for unstable angina, or
- hospitalization due to congestive heart failure
- Have New York Heart Association Functional Classification Class IV congestive heart failure
- Have a history of chronic or acute pancreatitis
- Have taken weight loss drugs, including over-the counter medications within 90 days prior to screening
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (31)
Artemis Institute for Clinical Research
Riverside, California, 92503, United States
JEM Research Institute
Atlantis, Florida, 33462, United States
Headlands Research Orlando
Orlando, Florida, 32806, United States
Care Access - Tamarac
Tamarac, Florida, 33321, United States
Care Access - Arlington Heights
Arlington Heights, Illinois, 60005, United States
L-MARC Research Center
Louisville, Kentucky, 40213, United States
IMA Clinical Research Monroe - Armand
Monroe, Louisiana, 71201, United States
Pharmasite Research, Inc.
Baltimore, Maryland, 21208, United States
Clinical Research Professionals
Chesterfield, Missouri, 63005, United States
Clinvest Headlands Llc
Springfield, Missouri, 65807, United States
IMA Clinical Research Warren
Warren Township, New Jersey, 07059, United States
IMA Clinical Research Manhattan
New York, New York, 10036, United States
Trial Management Associates - Wilmington - Floral Parkway
Wilmington, North Carolina, 28403, United States
Cedar Health Research
Dallas, Texas, 75251, United States
Headlands Research-El Paso
El Paso, Texas, 79902, United States
Cedar Health Research - Euless
Euless, Texas, 76040, United States
Cedar Health Research - Fort Worth
Fort Worth, Texas, 76132, United States
Care Access - Houston
Houston, Texas, 77054, United States
IMA Clinical Research San Antonio
San Antonio, Texas, 78229, United States
FutureMeds - Birmingham
Birmingham, B21 9RY, United Kingdom
Layton Medical Centre
Blackpool, FY3 7EN, United Kingdom
Bradford on Avon Health Centre
Bradford-on-Avon, BA15 1DQ, United Kingdom
FutureMeds - Liverpool
Bromborough, CH62 6EE, United Kingdom
Cheadle Community Hospital
Cheadle, ST10 1NS, United Kingdom
HMC Health Group - Meadows Centre for Health
Hounslow, TW4 7NR, United Kingdom
St Bartholomew's Medical Centre
Oxford, OX4 1XB, United Kingdom
Atlantic Medical
Penzance, TR18 3DX, United Kingdom
The Adam Practice
Poole, BH16 5PW, United Kingdom
Woodstock Bower Surgery
Rotherham, S61 1AH, United Kingdom
Rame Group Practice
Torpoint, PL11 2TB, United Kingdom
Albany House Medical Centre
Wellingborough, NN8 4RW, United Kingdom
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Call 1-877-CTLILLY (1-877-285-4559) or 1-317-615-4559 Mon - Fri 8 AM - 8 PM Eastern time (UTC/GMT - 5 hours, EST)
Eli Lilly and Company
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
November 14, 2025
First Posted
November 18, 2025
Study Start
November 17, 2025
Primary Completion (Estimated)
July 1, 2027
Study Completion (Estimated)
July 1, 2027
Last Updated
April 17, 2026
Record last verified: 2026-04
Data Sharing
- IPD Sharing
- Will share
- Shared Documents
- STUDY PROTOCOL, SAP, CSR
- Time Frame
- Data are available 6 months after the primary publication or approval of the indication studied in the US and EU, whichever is later. Data will be indefinitely available for requesting.
- Access Criteria
- A research proposal should be approved by an independent review panel and researchers should sign a data sharing agreement.
Anonymized individual patient level data will be provided in a secure access environment upon approval of a research proposal and a signed data sharing agreement.