GLP-1 Evidence

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

Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial

Design
Randomized trial · 1152 participants · Intermediate outcome
Match to healthy normal-weight adults aged 55–75
Different populationObesity or overweight with type 2 diabetes was required and mean BMI was 38.2. Nothing in the abstract bears on normal-weight adults. Mean age 55 sits at the low end of the reference range.
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 2Large multicentre double-blind placebo-controlled phase 3 RCT with 80-week follow-up. The primary outcome is bodyweight, a surrogate for this observatory's questions. Sponsor funded, designed and analysed. 16% did not complete study drug, with more discontinuation on the two higher doses. Abstract-level appraisal.
Assessment
Version 4 · Checked against the source by AI · Oct 19, 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 3 TRIUMPH-2 trial of the triple agonist retatrutide: about 12 to 14 percentage points more weight loss than placebo at the 9 mg and 12 mg doses (about 7 points at 4 mg) over 80 weeks in adults with obesity and type 2 diabetes. Beyond the familiar gastrointestinal profile, two dose-related adverse effects stand out: hypotension and dysesthesia (abnormal skin sensation). Says nothing about normal-weight adults.

01Findings

What the study reported

Drugs
Retatrutide
Dose
4, 9 or 12 mg weekly
Route
subcutaneous
Treatment duration
80 weeks
Comparator
placebo
Primary outcome
Percentage change in bodyweight from baseline to week 80 (9 mg and 12 mg vs placebo; 4 mg key secondary)
Effect
Bodyweight -11.9% (4 mg), -16.8% (9 mg), -18.8% (12 mg) vs -5.1% placebo; treatment differences -6.9, -11.8 and -13.8 percentage points
95% confidence interval
-8.7 to -5.1 (4 mg); -13.7 to -9.8 (9 mg); -15.8 to -11.8 (12 mg)
P value
<0.0001 for all doses
Follow-up
80 weeks
Adverse events
Gastrointestinal events most frequent: diarrhoea 27-34% vs 13%, nausea 14-28% vs 8%. Hypotension 1%, 5% and 6% (4, 9, 12 mg) vs <1% placebo. Dysesthesia 4%, 6% and 7% vs 1%. Permanent discontinuation for adverse events or death 4%, 12% and 8% vs 5%. Seven deaths (six on retatrutide, one on placebo), all judged unrelated by the investigators.
Limitations
Assessed from the abstract. Bodyweight is the primary outcome; no clinical event outcomes. The population is obesity with type 2 diabetes. The mechanism, time course and reversibility of dysesthesia are not described in the abstract.

Who was studied

Mean age
55.1
Age min
18
Sex distribution
48% female
Bmi mean
38.2
Bmi min
27
Obesity status
BMI >= 27 required; median duration of obesity 21 years
Diabetes status
type 2 diabetes required (median duration 5.6 years; 92% on oral glucose-lowering drugs)
Baseline condition
obesity with type 2 diabetes
Sample size
1152

Study quality details

Study design
Randomized controlled trial
Sample size
1152
Randomization
yes
Blinding
double-blind
Comparator
placebo
Follow up duration
80 weeks
Outcome type
intermediate
Replication
not assessed (auto)
Consistency with other evidence
not assessed (auto)
Population applicability
INDIRECT
Statistical precision
CI reported: -8.7 to -5.1 (4 mg); -13.7 to -9.8 (9 mg); -15.8 to -11.8 (12 mg)
Risk of bias
not assessed (auto)
Funding conflicts
yes
Peer review status
yes
02Funding

Funding and conflicts

Funding
Eli Lilly and Company
Industry funded
Yes
Manufacturer
Eli Lilly
Sponsor role
Sponsor funded, designed and analysed the trial.
Author conflicts
Authors declare consulting, speaking and research relationships with Eli Lilly, Novo Nordisk, Boehringer Ingelheim, Sanofi and others; sponsor employees are 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 is an agonist of GIP, GLP-1, and glucagon receptors, and is currently under investigation for the treatment of obesity, type 2 diabetes, and other comorbidities, including knee osteoarthritis and obstructive sleep apnoea. We aimed to assess the efficacy and safety of retatrutide in adults with obesity and type 2 diabetes. [METHODS] TRIUMPH-2 was a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial conducted at 92 medical and research centres and hospitals across eight countries. We enrolled adults (aged ≥18 years) with a BMI of 27 kg/m2 or higher and type 2 diabetes (glycated haemoglobin [HbA1c] 6·5-10·5%) on stable treatment for type 2 diabetes for at least 90 days before screening (diet or exercise alone, or up to three oral glucose-lowering medications), and a history of at least one self-reported unsuccessful dietary effort to reduce bodyweight. Participants were randomly assigned (1:1:1:1), using an interactive web-response system, to receive once-weekly subcutaneous injections (self-administered) of placebo or retatrutide 4 mg, 9 mg, or 12 mg. The primary endpoint was the percentage change from baseline to week 80 in bodyweight for the retatrutide 9 mg and 12 mg doses versus placebo, with 4 mg versus placebo a key secondary endpoint. Efficacy analyses included all randomly assigned participants, with missing data imputed with a primary multiple imputation strategy for the treatment regimen estimand. Safety analyses included all randomly assigned participants who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, NCT05929079 (completed). [FINDINGS] Between July 11, 2023, and Nov 1, 2024, 2047 participants were screened, and 1152 (mean age 55·1 years [SD 10·8], 554 [48%] females and 598 [52%] males, and 672 [58%] of White ethnicity) were randomly assigned to retatrutide 4 mg (n=292), 9 mg (n=284), or 12 mg (n=287), or placebo (n=289). At baseline, the mean BMI was 38·2 kg/m2 (SD 7·4), mean HbA1c was 7·71% (1·07), median duration of obesity was 21 years (IQR 11-31), and median duration of diabetes was 5·6 years (2·6-10·4). At baseline, 1055 (92%) of 1152 participants were on any oral glucose-lowering medication, including biguanides, SGLT2 inhibitors, sulfonylureas, and other oral glucose-lowering medications. Of 1152 participants, 965 (84%) completed the study drug. For the treatment regimen estimand, the mean percentage change from baseline in bodyweight at week 80 was -11·9% (SE 0·6) with retatrutide 4 mg, -16·8% (0·7) with retatrutide 9 mg, -18·8% (0·7) with retatrutide 12 mg, and -5·1% (0·7) with placebo. Estimated treatment differences compared with placebo for percentage change in bodyweight were -6·9% (95% CI -8·7 to -5·1) with retatrutide 4 mg, -11·8% (-13·7 to -9·8) with retatrutide 9 mg, and -13·8% (-15·8 to -11·8) with retatrutide 12 mg (p<0·0001 for all). The most frequently reported adverse events were gastrointestinal, which were more common in the retatrutide groups than in the placebo group (diarrhoea occurred in 80 [27%] of 292 participants in the 4 mg group, 95 [34%] of 284 in the 9 mg group, and 96 [34%] of 286 in the 12 mg group vs 38 [13%] of 287 in the placebo group, and nausea occurred in 40 [14%], 59 [21%], and 80 [28%] vs 23 [8%]). Hypotension and dysesthesia were more frequent with retatrutide than with placebo (four [1%] in the 4 mg group, 14 [5%] in the 9 mg group, and 18 (6%) in the 12 mg group vs one [<1%] in the placebo group with hypotension; 13 [4%], 16 [6%], and 21 [7%] vs two [1%] in the placebo group with dysesthesia). Permanent treatment discontinuation due to adverse events or death was more frequent in participants treated with retatrutide 9 mg (33 [12%]) and 12 mg (22 [8%]) compared with retatrutide 4 mg (11 [4%]) and placebo (14 [5%]). Two participants died in the retatrutide 4 mg group, three in the 9 mg group, one in the 12 mg group, and one in the placebo group; all deaths were deemed to be unrelated to the study intervention by the investigator. [INTERPRETATION] Treatment with retatrutide resulted in substantial improvements in bodyweight and was associated with improvements in glycaemic control in participants with obesity and type 2 diabetes, with a safety profile generally consistent with other molecules with GLP-1 receptor agonism. These results show that retatrutide might be effective for the treatment of obesity in people with type 2 diabetes. [FUNDING] Eli Lilly and Company.

Where this record came from

SourceRetrievedIdentifier
pubmedSep 30, 202642810372
first ingestion
pubmedSep 30, 202642810372
duplicate matched on doi
pubmedOct 4, 202642810372
duplicate matched on doi
pubmedOct 4, 202642810372
duplicate matched on doi
pubmedOct 11, 202642810372
duplicate matched on doi
pubmedOct 11, 202642810372
duplicate matched on doi