Meta-Analysis of Comparison of the Newer Oral P2Y12 Inhibitors (Prasugrel or Ticagrelor) to Clopidogrel in Patients With Non-ST-Elevation Acute Coronary Syndrome.

Newer oral P2Y12 inhibitors are more potent and have faster onset of action than clopidogrel. However, the efficacy and safety in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) are not well studied. A systemic search of MEDLINE and EMBASE databases was performed to identify randomized clinical trials comparing newer oral P2Y12 inhibitors (prasugrel or ticagrelor) to clopidogrel in patients with NSTE-ACS. The primary outcome was a composite of cardiovascular death, myocardial infarction (MI), and stroke (major cardiovascular events [MACE]). Secondary outcomes were individual components of the primary outcome, all-cause mortality, and Thrombolysis In Myocardial Infarction (TIMI) major and minor bleeding. A total of 31,470 patients with NSTE-ACS from 4 randomized clinical trials were included (newer oral P2Y12 inhibitors: 15,951; clopidogrel: 15,519). Newer oral P2Y12 inhibitors significantly decreased MACE (relative risk [RR] 0.87, 95% confidence interval [CI] 0.80 to 0.95) and MI (RR 0.85, 95% CI 0.75 to 0.96) and showed a trend toward reduction of cardiovascular death (RR 0.89, 95% CI 0.71 to 1.01). There was a significant increase in TIMI major bleeding (RR 1.27, 95% CI 1.07 to 1.50) and TIMI major or minor bleeding (RR 1.20, 95% CI 1.02 to 1.42). Results were largely similar when stratified by ticagrelor versus prasugrel (pinteraction >0.05) except for increased TIMI major/minor bleeding with prasugrel than ticagrelor (pinteraction = 0.01). In conclusion, in patients with NSTE-ACS, newer oral P2Y12 inhibitors decrease MACE and MI at the expense of a significant increase in the risk of bleeding. Treatment of 1,000 patients with newer oral P2Y12 inhibitors will prevent 16 MACE and 13 MIs at the expense of increase in 6 major bleeding events.