TRIUMPH-2 Results: Retatrutide Produced 20.8% Mean Weight Loss in Adults With Type 2 Diabetes
Summary: Eli Lilly announced TRIUMPH-2 topline Phase 3 results on July 23, 2026. In adults with obesity or overweight and type 2 diabetes, retatrutide produced mean body-weight reductions under the efficacy estimand at 80 weeks of 12.7% (4 mg), 19.1% (9 mg), and 20.8% (12 mg) versus 4.0% on placebo. A1C reductions averaged 1.6 percentage points. These are topline company results; peer-reviewed publication is pending. Retatrutide is not FDA-approved and is not commercially available.
TRIUMPH-2 Dose-Level Results (Efficacy Estimand, 80 Weeks)
| Dose | Mean Weight Loss | Placebo |
|---|---|---|
| 4 mg | −12.7% | −4.0% |
| 9 mg | −19.1% | −4.0% |
| 12 mg | −20.8% | −4.0% |
| Placebo | −4.0% | — |
Source: Eli Lilly topline announcement, July 23, 2026. Efficacy estimand. Peer-reviewed publication pending. Cross-trial comparisons are not equivalent to head-to-head trials.
Study Population and Design
TRIUMPH-2 enrolled adults with obesity or overweight and type 2 diabetes. The trial ran for 80 weeks. Estimated enrollment was approximately 2,500 participants. Participants were randomized to receive retatrutide at 4 mg, 9 mg, or 12 mg once weekly, or placebo.
A1C Findings
In addition to weight loss, TRIUMPH-2 reported A1C reductions averaging 1.6 percentage points. This is a clinically meaningful reduction for adults with type 2 diabetes. Full A1C data by dose and comparison to placebo are pending peer-reviewed publication.
Topline vs. Peer-Reviewed Evidence
Topline results are a company announcement of primary endpoints. They have not been independently reviewed by scientific peers, do not include the full dataset, and may not include all safety and secondary endpoint data. The figures reported here are from Eli Lilly's July 23, 2026 investor relations announcement. Peer-reviewed publication of the complete TRIUMPH-2 dataset is pending.
Cross-Trial Comparison Warning
TRIUMPH-2 results (20.8% at 12 mg) are lower than TRIUMPH-1 results (28.3% at 12 mg). This difference is expected: TRIUMPH-2 enrolled participants with type 2 diabetes, who typically show somewhat lower weight loss responses to GLP-1-based therapies. These trials had different populations, designs, and durations. Cross-trial comparisons are not equivalent to head-to-head trials and should be interpreted with caution.
Evidence Status
All TRIUMPH-2 data in this article are from Eli Lilly's July 23, 2026 topline announcement. This is a company press release, not a peer-reviewed publication. Full study data, safety profile, and secondary endpoints are pending peer-reviewed publication. Retatrutide is not FDA-approved.
Frequently Asked Questions
What were the TRIUMPH-2 results?
TRIUMPH-2 topline results announced July 23, 2026 showed mean body-weight reductions under the efficacy estimand at 80 weeks of: 4 mg −12.7%, 9 mg −19.1%, 12 mg −20.8%, vs. placebo −4.0%. A1C reductions averaged 1.6 percentage points. These are Eli Lilly topline results; peer-reviewed publication is pending.
Who was in the TRIUMPH-2 trial?
TRIUMPH-2 enrolled adults with obesity or overweight and type 2 diabetes. The trial ran for 80 weeks. Estimated enrollment was approximately 2,500 participants.
How do TRIUMPH-2 results compare to TRIUMPH-1?
TRIUMPH-1 (obesity without required T2D) showed 28.3% mean weight loss at 80 weeks at 12 mg. TRIUMPH-2 (T2D + obesity) showed 20.8% at 12 mg. The difference is expected: participants with type 2 diabetes typically show somewhat lower weight loss responses to GLP-1-based therapies. Cross-trial comparisons are not equivalent to head-to-head trials.
What is the difference between topline results and peer-reviewed publication?
Topline results are a company announcement of primary endpoints. They have not been independently reviewed by scientific peers, do not include the full dataset, and may not include all safety and secondary endpoint data. Peer-reviewed publication involves independent expert review of the complete study data. TRIUMPH-2 peer-reviewed publication is pending.
Does TRIUMPH-2 mean retatrutide is approved for type 2 diabetes?
No. Retatrutide is not FDA-approved for any indication. TRIUMPH-2 is a Phase 3 clinical trial. Positive topline results support a future regulatory submission to the FDA, which Eli Lilly plans for Q1 2027. FDA approval requires successful review and is not guaranteed.