A comparative study of Clopidogrel Versus Prasugrel in unstable coronary artery disease managed conservatively

Abstract

Background: Dual anti-platelet therapy is cornerstone in the management of patients with acute coronary syndrome (ACS). The most commonly prescribed combination is aspirin (A) and clopidogrel (C). However, both drugs have the problem of drug resistance (5-40% and 30%, respectively), resulting into vascular events. Prasugrel (P), the newer antiplatelet agent is supposedly better because of different pharmacokinetic profile. However, it is not approved for use in patients with ACS not undergoing intervention. Aim: The present study was aimed at evaluating the effects of P and C on recurrent angina, MI, and stroke within 30 days in patients with ACS managed conservatively, with similar background therapy. Methods: This study was done on 63patients presenting with ACS, diagnosed on the basis of clinical history, ECG findings and cardiac enzymes changes, managed conservatively. The patients were randomized in a1:1 fashion in two groups. The group 1 patients received P (60 mg loading followed by 10 mg P.O. daily, dose was reduced to 30 mg loading and 5 mg maintenance dose in patients aged > 75 years and weight < 60 kgs) and the group 2 patients received C (300mg loading followed by 75 mg P.O. daily). Patient in both the groups received aspirin (325 mg loading followed by 75 mg P.O. daily), atorvastatin (40 mg P.O. daily), weight adjusted enoxaparin and antianginal therapy as appropriate. There were no significant demographic differences between patients in the two groups. Result: The study showed that patients on P responded better, irrespective of age, sex, presence or absence of diabetes, dyslipidemia, ECG changes, and troponin positivity. There was a relative risk reduction of 35.61% (relative risk (RR), 0.64; 95% confidence interval (CI), 0.44-1.01; P=0.05) in the incidence of composite of primary end points in the group receiving prasugrel. No major or minor bleeding episodes were seen in any patient. Although our study is under powered, it creates space for a larger study with prasugrel to find out the true significance of our observation. Conclusions: The present study concluded that prasugrel significantly reduces the incidence of composite of refractory ischemia, MI and CV death and non-significantly reduced refractory ischemia, MI and CV death in patients of ACS managed conservatively.