Comparing newer oral anti-platelets prasugrel and ticagrelor in reduction of ischemic events-evidence from a network meta-analysis

Abstract

The two newer antiplatelet drugs, prasugrel and ticagrelor have both been incorporated in various national guidelines and are both under consideration for approval or have already been approved by various drug regulatory authorities. Mortality benefits with clopidogrel were comparable to newer anti-platelets, and prasugrel had great anti-ischemic potency than ticagrelor. We searched PubMed, EMBASE and Cochrane Central Register of Controlled Trials' databases for randomized controlled trials conducted between 1990 and 2012 that assessed clinical outcomes with prasugrel or ticagrelor. The comparator was standard dosage of clopidogrel. Outcomes assessed were the risk of all causes mortality, TIMI non-CABG major bleeding, and a composite of stent thrombosis, recurrent ischemia and serious recurrent ischemia in the intervention groups versus the comparator groups. Event rates were compared using a forest plot of relative risk using a random effects model (Mantel-Haenszel); and Odd's ratio was calculated in the absence of significant heterogeneity. Prasugrel was indirectly compared with ticagrelor using network meta-analysis. Four studies (total N=34,126) met the inclusion/exclusion criteria. Both drugs had improved mortality and greater risk of bleeding compared to clopidogrel; but outcomes were comparable for both (p=NS). However a composite of recurrent ischemic events, including rates of stent thrombosis (p=0.045) was reduced to a modest degree with prasugrel compared with ticagrelor. This systematic review suggests greater clinical efficacy of both prasugrel and ticagrelor compared with clopidogrel and an indirect comparison indicates prasugrel may be more effective than ticagrelor for preventing stent thrombosis and recurrent ischemic events.