# IMPROVE-IT (ezetimibe added to simvastatin after acute coronary syndrome)

Study · id `cardio:improve-it` · Cardiovascular Atlas · release `f6f6f1b6f50379ed` (public)

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Also called: IMPROVE-IT; IMProved Reduction of Outcomes: Vytorin Efficacy International Trial

Browse, condition area: Coronary and vascular disease  

## In plain language

A large trial of 18,144 people who had recently been in hospital with an acute coronary syndrome. Everyone took the statin simvastatin, and half also took the cholesterol pill ezetimibe. Adding ezetimibe lowered LDL cholesterol further and gave a small extra reduction in heart and blood-vessel events over 7 years.

## Technical summary

Phase 3, double-blind randomized trial (NCT00202878): simvastatin 40 mg with ezetimibe 10 mg against simvastatin 40 mg with placebo, 18,144 participants enrolled, 2005-10-17 to 2014-09-18. The abstract reports a 7-year Kaplan-Meier primary event rate of 32.7% against 34.7% (hazard ratio 0.936, 95% CI 0.89 to 0.99). The paper says the trial was funded by Merck; the registry now lists Organon and Co as lead sponsor. The registry names hypercholesterolemia and myocardial infarction as conditions.

## Key facts

- Design: Allocation: randomized. Intervention model: parallel. Masking: triple. Primary purpose: treatment. (Registry values, in lower case.)
- Phase: Phase 3
- Enrolled: 18144 participants (enrolled count; IMPROVE-IT: Examining Outcomes in Subjects With Acute Coronary Syndrome: Vytorin (Ezetimibe/Simvastatin) vs Simvastatin (P04103), snapshot `cardio:ctgov-nct00202878-2026-10-14`, retrieved 2026-10-14)
- Started: 2005-10-17 (actual) (IMPROVE-IT: Examining Outcomes in Subjects With Acute Coronary Syndrome: Vytorin (Ezetimibe/Simvastatin) vs Simvastatin (P04103), snapshot `cardio:ctgov-nct00202878-2026-10-14`, retrieved 2026-10-14)
- Primary completion: 2014-09-18 (actual) (IMPROVE-IT: Examining Outcomes in Subjects With Acute Coronary Syndrome: Vytorin (Ezetimibe/Simvastatin) vs Simvastatin (P04103), snapshot `cardio:ctgov-nct00202878-2026-10-14`, retrieved 2026-10-14)
- Completion: 2014-09-18 (actual) (IMPROVE-IT: Examining Outcomes in Subjects With Acute Coronary Syndrome: Vytorin (Ezetimibe/Simvastatin) vs Simvastatin (P04103), snapshot `cardio:ctgov-nct00202878-2026-10-14`, retrieved 2026-10-14)
- Results first posted: 2015-09-30 (IMPROVE-IT: Examining Outcomes in Subjects With Acute Coronary Syndrome: Vytorin (Ezetimibe/Simvastatin) vs Simvastatin (P04103), snapshot `cardio:ctgov-nct00202878-2026-10-14`, retrieved 2026-10-14)
- Countries: Not reported
- Care setting: Not reported
- Registry status: "COMPLETED" (U.S. National Library of Medicine (ClinicalTrials.gov), snapshot `cardio:ctgov-nct00202878-2026-10-14`, retrieved 2026-10-14)

## Connected pages

- Tests ezetimibe added to simvastatin: Ezetimibe (`cardio:ezetimibe`)
- Lists myocardial infarction as a condition: Heart attack (myocardial infarction) (`cardio:myocardial-infarction`)

## Provenance

Content hash: c1d13da6f261929daaecbcddf23e8bc8ff343f9c9c90de1ed55ce6d57f441804
Last substantive edit: 2026-10-14
Evidence last checked: 2026-10-14