The Stabilization Of pLaques usIng Darapladib-Thrombolysis In Myocardial Infarction 52 Trial

This study will test whether darapladib can safely lower the chances of having a cardiovascular event (such as a heart attack or urgent coronary revascularization (e.g. medical procedures performed to restore the normal blood flow in patients with atherosclerosis)) when treatment is started within 30 days after an acute coronary syndrome (also called ACS).

Subjects who qualify for the study will be randomized 1:1 to either darapladib or placebo administered in addition to standard therapy. Following the baseline visit, subjects will be expected to return for clinic visits at 1 month, 3 months, 6 months and every 6 months until the end of the study.

Eligibility Criteria:
Inclusion Criteria:

* Signed written informed consent.
* Men or women at least 18 years old (in Taiwan, at least 20 years old). Women must be post-menopausal or using a highly effective method for avoidance of pregnancy.
* Hospitalization for acute coronary syndrome (ACS) within 30 days prior to study entry.
* Clinically stable for 24 hours prior to study entry.
* A planned percutaneous coronary intervention (PCI) should be performed prior to study entry, whenever possible.
* At least one of the following:
* At least 60 years old.
* Myocardial infarction prior to the qualifying ACS event.
* Diabetes mellitus requiring treatment with medication.
* Diagnosed mild or moderate reduction in kidney function.
* Cerebrovascular disease (carotid artery disease or ischemic stroke more than 3 months prior to study entry) OR peripheral artery disease.

Exclusion Criteria:

* ACS symptoms or lab results not believed to be caused by a narrowing or blocked coronary artery.
* No major coronary artery with a blockage of more than 50% (unless all stenoses are successfully treated by PCI).
* Planned coronary artery bypass graft (CABG) surgery, or CABG surgery performed after the qualifying ACS event and prior to study entry.
* Certain types of liver disease.
* Severe reduction in kidney function OR removal of a kidney OR kidney transplant.
* Severe heart failure.
* Blood pressure higher than normal despite lifestyle changes and treatment with medications.
* Any life-threatening disease with a life expectancy of less than 2 years (other than heart disease) that may prevent the subject from completing the study.
* Severe asthma that is poorly controlled with medication.
* Pregnancy (Note: A pregnancy test will be performed on all non-sterile women prior to study entry).
* Previous severe allergic reaction to food, medications, drink, insect stings, etc.
* Drug or alcohol abuse within the past 6 months. Mental/psychological impairment that may prevent the subject from complying with study procedures or understanding the goal and potential risks of participating in the study.
* Certain medications that may interfere with the study medication (these will be identified by the study doctor).
* If both birth parents are at least 50% Japanese, Chinese, or Korean ancestry, must have a blood sample collected for Lp-PLA2 activity. Those with Lp-PLA2 activity less than or equal to 20.0 nmol/min/mL are excluded.
* Previously took darapladib (SB-480848).
* Participation in a study of an investigational medication within the past 30 days.
* Current participation in a study of an investigational device.
* Any other reason the investigator deems the subject should not participate in the study.