Background: The patients of unstable angina / non-ST-elevation myocardial infarction (UA/NSTEMI) who are managed medically continue to have high risk of future adverse clinical outcomes and remain an understudied population of patients. The primary objective of this study was to compare the relative efficacy and safety of prasugrel and clopidogrel in medically managed patients of high risk UA/NSTEMI.

Methods: In this open label, prospective randomized study, 100 consecutive patients of high risk UA/NSTEMI were studied under two groups of 50 each. In one group, prasugrel was used with 40 mg as loading dose & 10 mg as maintenance dose while in the second group, clopidogrel was used as 300 mg loading dose followed by 75 mg as maintenance dose for a study period of 1 month. The patients were observed for the primary and secondary efficacy end points during the hospital stay (0-5 days) and follow up at 30 days.

Results: The patients in the prasugrel group had lower incidence of major adverse cardiac events (MACE) as compared to clopidogrel group both during hospital stay (6 versus 16, p ˂ 0.05) and total number of adverse cardiac events observed during the study period of 1 month (10 versus 19, p ˂ 0.05 ). Although statistically insignificant, due to small sample size of study population, prasugrel was demonstrated to have better efficacy in diabetic cohort of the patients. For safety concerns, no any episode of major bleeding was observed with either of the drugs and minor bleeding rate was comparable between the two groups.

Conclusion: Prasugrel resulted in greater benefit in reducing the ischemic events and improving the net outcome of ACS (high risk UA/NSTEMI) population in comparison to the standard clopidogrel therapy.

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Dr Vikas Chaudhary

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