GLP-1 Evidence

Not medical advice. A record of published research and our assessments of it. The limits

Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial

Design
Randomized trial · 338 participants · Intermediate outcome
Match to healthy normal-weight adults aged 55–75
Different populationObesity; weight-loss dose-finding trial. Included here for the heart-rate safety signal and as the reference for triple-agonist programmes.
Could weight loss explain it?
Not applicable[Auto] Participants had obesity and/or type 2 diabetes and the abstract does not separate direct drug effects from weight loss or glycaemic improvement.
Study tier
Study tier 2[Auto] Randomized trial of moderate size; outcome type and follow-up limit certainty (auto-provisional).
Assessment
Version 2 · curated · Sep 13, 2026

Study facts come from the paper. Population match, weight-loss explanation and study tier are our judgments, made against the reference group of healthy normal-weight adults aged 55–75.

Phase 2 trial of the triple agonist retatrutide: up to 24% weight loss at 48 weeks in adults with obesity, with dose-related gastrointestinal effects and increases in heart rate. Sets the stage for TRIUMPH and TRANSCEND trials.

01Findings

What the study reported

Drugs
Retatrutide
Dose
1 to 12 mg weekly
Route
subcutaneous
Treatment duration
48 weeks
Comparator
placebo
Primary outcome
Percent change in body weight at 24 weeks
Effect
-24.2% at 48 weeks (12 mg) vs -2.1% placebo; dose-dependent heart-rate increase peaking at 24 weeks
95% confidence interval
Not extracted
Follow-up
48 weeks
Adverse events
Dose-related GI events; dose-dependent heart-rate increase.
Limitations
Auto-classified from abstract only; effect estimates, adverse events and limitations not extracted. Requires manual review.

Who was studied

Sex distribution
48.2% female
Bmi min
30
Obesity status
obesity or overweight with comorbidity
Sample size
338

Study quality details

Study design
Randomized controlled trial
Sample size
338
Randomization
yes
Blinding
double-blind
Comparator
placebo
Follow up duration
48 weeks
Outcome type
unknown
Replication
not assessed (auto)
Consistency with other evidence
not assessed (auto)
Population applicability
INDIRECT
Statistical precision
not extracted
Risk of bias
not assessed (auto)
Funding conflicts
yes
Peer review status
yes
02Funding

Funding and conflicts

Funding
Eli Lilly
Industry funded
Yes
Manufacturer
Eli Lilly
Sponsor role
Sponsor designed and analysed.
Author conflicts
Authors report Eli Lilly relationships; sponsor co-authors.
Independent replication
unknown
Notes
Authors declare relationships with the drug's manufacturer: Eli Lilly

Funding is shown on every study and never used to score it.

04Source

The source, as retrieved

Abstract

[BACKGROUND] Retatrutide (LY3437943) is an agonist of the glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and glucagon receptors. Its dose-response relationships with respect to side effects, safety, and efficacy for the treatment of obesity are not known. [METHODS] We conducted a phase 2, double-blind, randomized, placebo-controlled trial involving adults who had a body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) of 30 or higher or who had a BMI of 27 to less than 30 plus at least one weight-related condition. Participants were randomly assigned in a 2:1:1:1:1:2:2 ratio to receive subcutaneous retatrutide (1 mg, 4 mg [initial dose, 2 mg], 4 mg [initial dose, 4 mg], 8 mg [initial dose, 2 mg], 8 mg [initial dose, 4 mg], or 12 mg [initial dose, 2 mg]) or placebo once weekly for 48 weeks. The primary end point was the percentage change in body weight from baseline to 24 weeks. Secondary end points included the percentage change in body weight from baseline to 48 weeks and a weight reduction of 5% or more, 10% or more, or 15% or more. Safety was also assessed. [RESULTS] We enrolled 338 adults, 51.8% of whom were men. The least-squares mean percentage change in body weight at 24 weeks in the retatrutide groups was -7.2% in the 1-mg group, -12.9% in the combined 4-mg group, -17.3% in the combined 8-mg group, and -17.5% in the 12-mg group, as compared with -1.6% in the placebo group. At 48 weeks, the least-squares mean percentage change in the retatrutide groups was -8.7% in the 1-mg group, -17.1% in the combined 4-mg group, -22.8% in the combined 8-mg group, and -24.2% in the 12-mg group, as compared with -2.1% in the placebo group. At 48 weeks, a weight reduction of 5% or more, 10% or more, and 15% or more had occurred in 92%, 75%, and 60%, respectively, of the participants who received 4 mg of retatrutide; 100%, 91%, and 75% of those who received 8 mg; 100%, 93%, and 83% of those who received 12 mg; and 27%, 9%, and 2% of those who received placebo. The most common adverse events in the retatrutide groups were gastrointestinal; these events were dose-related, were mostly mild to moderate in severity, and were partially mitigated with a lower starting dose (2 mg vs. 4 mg). Dose-dependent increases in heart rate peaked at 24 weeks and declined thereafter. [CONCLUSIONS] In adults with obesity, retatrutide treatment for 48 weeks resulted in substantial reductions in body weight. (Funded by Eli Lilly; ClinicalTrials.gov number, NCT04881760.).

Where this record came from

SourceRetrievedIdentifier
pubmedSep 13, 202637366315
first ingestion