TRIUMPH-2: full retatrutide results in type 2 diabetes published in The Lancet
Full TRIUMPH-2 results for retatrutide in people with obesity and type 2 diabetes were presented at EASD and published in The Lancet. What the data show.
By the RetaRadar team · Updated 30 September 2026
Full results from TRIUMPH-2, the phase 3 trial of retatrutide in adults with obesity or overweight and type 2 diabetes, were presented at the European Association for the Study of Diabetes (EASD) meeting in Milan on 29 September 2026 and published in The Lancet, according to Eli Lilly’s announcement.
What the trial tested
TRIUMPH-2 (NCT05929079) enrolled 1,152 people and ran for 80 weeks, comparing retatrutide with placebo. People with type 2 diabetes usually lose less weight on GLP-1 medicines than people without it, so this trial is an important test of how far the triple-agonist approach goes in that group.
The headline numbers
When Lilly first reported topline results in July 2026, it said:
- average weight change in the highest dose arm was −20.8%, against −4.0% on placebo;
- HbA1c, a measure of long-term blood sugar, fell by 1.4 to 1.6 percentage points across doses, against 0.2 on placebo;
- 7.7% of the highest dose arm stopped treatment because of side effects, against 4.9% on placebo (the middle dose arm was higher, at 11.6%).
These figures use Lilly’s “efficacy estimand”, which assumes people stayed on treatment.
How it compares with the other phase 3 trials
The weight loss in TRIUMPH-2 is smaller than in TRIUMPH-1, where people without diabetes lost an average of 28.3% in the highest dose arm. That pattern matches earlier results for semaglutide and tirzepatide. Our retatrutide guide sets out all five phase 3 readouts side by side.
What it means for the UK
Nothing changes yet. Retatrutide remains an investigational medicine and is not authorised by the MHRA. Lilly has said it plans to apply to the US FDA in early 2027 but has not given dates for UK or EU applications. People with type 2 diabetes who want help with weight should ask their GP about licensed options — see Mounjaro and Wegovy on the NHS.
For how we rate research-grade suppliers, see how we rate.