Rationale and design of IMPROVE-IT (IMProved Reduction of Outcomes: Vytorin Efficacy International Trial): comparison of ezetimbe/simvastatin versus simvastatin monotherapy on cardiovascular outcomes in patients with acute coronary syndromes.
BACKGROUND
Reduction in low-density lipoprotein cholesterol (LDL-C) improves clinical outcomes in patients with chronic coronary artery disease and acute coronary syndromes (ACSs). The combination of ezetimibe/simvastatin produces greater reductions in LDL-C compared to simvastatin monotherapy. The IMProved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT) is a multicenter, randomized, double-blind, active-control trial designed to test the hypothesis that the addition of ezetimibe to statin therapy, using ezetimibe/simvastatin, will translate into increased clinical benefit on cardiovascular outcomes relative to simvastatin monotherapy in patients with ACS.


METHODS
The study will recruit up to 18,000 moderate- to high-risk patients stabilized after ACS. Patients are randomized in a 1:1 ratio to once-daily doses of either ezetimibe/simvastatin 10/40 mg or simvastatin monotherapy 40 mg. Follow-up visits are at 1 and 4 months, and every 4 months thereafter. If consecutive measures of LDL-C are >79 mg/dL at follow-up visits, the simvastatin dose will be increased to 80 mg in a double-blind manner. The primary end point is the first occurrence of cardiovascular death, nonfatal myocardial infarction, rehospitalization for unstable angina, coronary revascularization (occurring at least 30 days after randomization), or stroke. Patients will be followed for a minimum of 2.5 years and until at least 5,250 patients experience a primary end point.


CONCLUSIONS
IMPROVE-IT will determine whether the addition of ezetimibe to statin therapy, using ezetimibe/simvastatin, improves cardiovascular outcomes compared with simvastatin monotherapy in patients after ACS. In addition, the difference in achieved LDL-C levels between the groups will provide data on whether the target for LDL-C lowering should be reduced further.
Cannon
Christopher P
CP
The TIMI Study Group, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA 02115, USA. cpcannon@partners.org
Giugliano
Robert P
RP
Blazing
Michael A
MA
Harrington
Robert A
RA
Peterson
John L
JL
Sisk
Christine McCrary
CM
Strony
John
J
Musliner
Thomas A
TA
McCabe
Carolyn H
CH
Veltri
Enrico
E
Braunwald
Eugene
E
Califf
Robert M
RM
D054058:Acute Coronary Syndrome / Q000188:drug therapy*; D000924:Anticholesteremic Agents / Q000008:administration & dosage*; D001384:Azetidines / Q000627:therapeutic use*; D004311:Double-Blind Method; D004338:Drug Combinations; D000069499:Ezetimibe, Simvastatin Drug Combination; D006801:Humans; D015337:Multicenter Studies as Topic; D019821:Simvastatin / Q000008:administration & dosage* / Q000627:therapeutic use; D016896:Treatment Outcome
D000924:Anticholesteremic Agents; D001384:Azetidines; D004338:Drug Combinations; D000069499:Ezetimibe, Simvastatin Drug Combination; D019821:Simvastatin