Tirzepatide Wins FDA Cardiovascular Indication: What the SURPASS-CVOT Trial Showed
TL;DR: FDA approved Mounjaro (tirzepatide) for cardiovascular risk reduction on 28 Aug 2026, based on the SURPASS-CVOT trial vs dulaglutide.
What Did the FDA Approve for Tirzepatide (Mounjaro) on 28 August 2026?
On 28 August 2026, the US Food and Drug Administration approved a new indication for Mounjaro (tirzepatide), Eli Lilly's dual GIP/GLP-1 receptor agonist, to reduce the risk of cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke in adults with type 2 diabetes who are at high cardiovascular risk.[1] The approval makes Mounjaro the first dual GIP/GLP-1 receptor agonist to carry a cardiovascular risk-reduction indication, extending its existing approvals for glycaemic control in type 2 diabetes and, under the Zepbound brand, chronic weight management.[2]
The approval rests on data from SURPASS-CVOT, a dedicated cardiovascular outcomes trial that compared tirzepatide head-to-head against dulaglutide (Trulicity), an older GLP-1 receptor agonist with its own established cardiovascular safety record.[3] Velox Peptides supplies tirzepatide as an HPLC-verified (≥99% purity) lyophilised reagent for in vitro research use only. Read the research overview →
What Is the SURPASS-CVOT Trial and How Was It Designed?
SURPASS-CVOT (NCT04255433) is a randomised, double-blind, active-comparator, noninferiority trial run across 30 countries. Investigators screened 16,979 adults with type 2 diabetes and established atherosclerotic cardiovascular disease (ASCVD) and randomised 13,165 of them — 6,586 to weekly subcutaneous tirzepatide (up to 15 mg) and 6,579 to weekly dulaglutide (1.5 mg) — with a median follow-up of roughly four years.[3]
Because SURPASS-CVOT compares tirzepatide against another active incretin drug rather than a placebo, it is designed to answer a different question from a placebo-controlled trial: not "does tirzepatide beat doing nothing," but "does tirzepatide perform at least as well as, or better than, an existing GLP-1 therapy with a proven cardiovascular safety profile." Dulaglutide was chosen as the comparator in part because of its own prior cardiovascular outcomes data.
What Were the Primary and Secondary Cardiovascular Results?
Population: 13,165 adults with type 2 diabetes and established ASCVD, randomised 1:1 to tirzepatide or dulaglutide across 30 countries.
Primary outcome (MACE-3 composite): 12.2% (801/6,586, tirzepatide) vs 13.1% (862/6,579, dulaglutide); HR 0.92 (95.3% CI 0.83–1.01); P=0.003 for noninferiority; P=0.09 for superiority (not met).
Expanded secondary endpoint (MACE-3 plus coronary revascularisation): Numerically lower with tirzepatide, reported as a nominally significant secondary finding by trial investigators.[4]
Safety: Overall adverse-event rates were broadly similar between arms, though gastrointestinal adverse events (nausea, diarrhoea, vomiting) were more frequent with tirzepatide, consistent with its known tolerability profile.
DOI: 10.1056/NEJMoa2505928 · N Engl J Med 2025;393:2409-2420 · ClinicalTrials.gov: NCT04255433
| Outcome | Hazard ratio (CI) | Interpretation |
|---|---|---|
| Primary MACE-3 composite | 0.92 (0.83–1.01) | Noninferior; superiority not met |
| Event rate, tirzepatide | 12.2% (801/6,586) | Reference arm result |
| Event rate, dulaglutide | 13.1% (862/6,579) | Active comparator result |
Table for research reference only; MACE-3 = cardiovascular death, myocardial infarction, or stroke.
The headline framing matters here: SURPASS-CVOT met its pre-specified noninferiority criterion, meaning tirzepatide was not meaningfully worse than dulaglutide on the primary composite outcome, but it did not meet the stricter, formally tested criterion for statistical superiority (P=0.09). The FDA's cardiovascular risk-reduction indication is grounded in this noninferiority finding together with the broader body of secondary and expanded-endpoint data, rather than a claim that tirzepatide is proven statistically superior to dulaglutide on the trial's primary measure.[3]
Why Did FDA Approval Come Eight Months After the Trial Was Published?
SURPASS-CVOT's full results were published in the New England Journal of Medicine on 17 December 2025, roughly eight months before the FDA's label decision on 28 August 2026.[3] That gap is typical for a supplemental application seeking a new indication on an already-approved drug: publication of trial results is a scientific milestone, not a regulatory filing, and the FDA separately reviews the complete dataset, statistical analysis plan, and manufacturing and labelling package before deciding whether to expand a product's approved use.
The timing also positions Mounjaro alongside Novo Nordisk's semaglutide (Ozempic/Wegovy), which already carries its own cardiovascular risk-reduction indication, intensifying head-to-head competition between the two companies' incretin franchises on cardiovascular, not just weight-loss or glycaemic, grounds.
How Does This Compare With the Earlier Real-World BMJ Cohort Study on Tirzepatide?
Velox previously covered a separate BMJ observational cohort study, published 5 August 2026, which found a hazard ratio of 0.68 for major cardiovascular events comparing tirzepatide against sitagliptin in real-world US claims data. That study and SURPASS-CVOT are not directly comparable: the BMJ analysis was retrospective, observational, and used sitagliptin (a DPP-4 inhibitor) as its comparator, while SURPASS-CVOT is a prospective, randomised, double-blind trial using dulaglutide (a GLP-1 receptor agonist) as an active comparator.
Two different questions, two different answers. The BMJ cohort study asked whether tirzepatide outperforms a non-incretin drug in everyday prescribing. SURPASS-CVOT asked whether tirzepatide is at least as cardiovascularly safe as an existing incretin drug in a controlled trial setting. Both point toward a favourable cardiovascular profile for tirzepatide, but they are complementary evidence streams rather than replications of the same finding, and only the randomised SURPASS-CVOT data formed the basis of the FDA's regulatory decision.
What Are the Limitations and Open Questions?
Noninferior, not superior
The primary composite endpoint met noninferiority but formally failed the pre-specified superiority test (P=0.09), so tirzepatide should not be described as definitively better than dulaglutide on that measure.
Narrow trial population
Participants all had type 2 diabetes and pre-existing atherosclerotic cardiovascular disease; the indication and trial data do not speak to cardiovascular outcomes in people without diabetes or without established heart disease.
Tolerability trade-off
More gastrointestinal adverse events occurred in the tirzepatide arm, a known class effect of GIP/GLP-1 agonism that clinicians weigh against the cardiovascular finding.
These caveats do not undermine the approval, but they do mean the indication should be read precisely: a noninferiority finding in a specific high-risk diabetes population, not a broad superiority claim across all patients.
Does This Affect Retatrutide's Story or UK Research-Reagent Supply?
No. This is a US regulatory decision and randomised trial concerning tirzepatide, a licensed pharmaceutical marketed as Mounjaro and Zepbound, and is entirely separate from retatrutide's own clinical programme, its ongoing FDA classification dispute, or its Q1 2027 filing timeline. It has no bearing on the UK regulatory position for research reagents under the Human Medicines Regulations 2012 — see our guide on whether research peptides are legal in the UK.
Tirzepatide and retatrutide are supplied as research reagents only. They are not medicines and have not been evaluated by the MHRA or FDA (in this research-reagent form). Not for human or veterinary use. See our Research Use Policy and MHRA Statement.
References
- Eli Lilly and Company. FDA approves Lilly's Mounjaro (tirzepatide) to reduce cardiovascular risk in adults with type 2 diabetes. Press release, 28 August 2026. investor.lilly.com
- BioSpace. Lilly joins Novo in cardiovascular space after FDA nod for GLP-1/GIP agonist Mounjaro. 28 August 2026. biospace.com
- Cardiovascular Outcomes with Tirzepatide versus Dulaglutide in Type 2 Diabetes. New England Journal of Medicine 2025;393:2409-2420. DOI: 10.1056/NEJMoa2505928. ClinicalTrials.gov: NCT04255433
- TCTMD. SURPASS-CVOT Published: Large Trial Confirms CVD Efficacy of Tirzepatide. December 2025. tctmd.com
- Velox Peptides. Tirzepatide and Cardiovascular Risk: What a New BMJ Cohort Study Found. See our BMJ cohort study guide for the comparable observational tirzepatide analysis.
Frequently Asked Questions
What did the FDA approve for tirzepatide (Mounjaro) on 28 August 2026?
The FDA approved a new indication for Mounjaro (tirzepatide) to reduce the risk of cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke in adults with type 2 diabetes who are at high cardiovascular risk. It is the first dual GIP/GLP-1 receptor agonist to receive a cardiovascular risk reduction indication.
What is the SURPASS-CVOT trial and how was it designed?
SURPASS-CVOT (NCT04255433) is a randomised, double-blind, active-comparator trial that screened 16,979 adults with type 2 diabetes and established atherosclerotic cardiovascular disease and randomised 13,165 of them (6,586 to tirzepatide, 6,579 to dulaglutide) across 30 countries, with a median follow-up of about four years.
What were the primary and secondary results of SURPASS-CVOT?
The primary composite endpoint (cardiovascular death, myocardial infarction, or stroke) occurred in 12.2% of the tirzepatide group versus 13.1% of the dulaglutide group, a hazard ratio of 0.92 (95.3% CI 0.83 to 1.01), meeting the pre-specified criterion for noninferiority (P=0.003) but not superiority (P=0.09). An expanded secondary endpoint that also included coronary revascularisation was numerically lower with tirzepatide.
How does this differ from the earlier BMJ real-world cohort study on tirzepatide?
SURPASS-CVOT is a randomised controlled trial comparing tirzepatide with dulaglutide, an active pharmaceutical comparator. A separate BMJ study published in August 2026 was an observational claims-data cohort comparing tirzepatide with sitagliptin. The two use different designs and comparators, so they are complementary rather than directly comparable, though both reported findings consistent with a cardiovascular benefit.
What are the limitations of the SURPASS-CVOT data?
The trial met noninferiority but not its stricter superiority criterion for the primary endpoint, so tirzepatide should not be described as definitively superior to dulaglutide on the primary composite outcome. The population was limited to adults with type 2 diabetes and established atherosclerotic cardiovascular disease, and more gastrointestinal adverse events occurred in the tirzepatide group.
Is tirzepatide available for research use?
Yes. Velox Peptides supplies tirzepatide as an HPLC-verified lyophilised research reagent for in vitro laboratory use only. It is not licensed as a medicine through Velox Peptides and is not supplied for human or veterinary use. Licensed pharmaceutical tirzepatide (Mounjaro, Zepbound) is a separate, MHRA/FDA-approved product manufactured by Eli Lilly and is not sold by Velox Peptides. Read the research overview →