TRILOGY ACS Substudy: Angiography Prior to Prasugrel Therapy Reduces CV Events

MIAMI BEACH, FLA.—Compared with clopidogrel, prasugrel lowers the rate of CVD, MI and stroke in patients triaged to medical therapy after angiography, according to results presented at TCT 2012.

Stephen D. Wiviott, MD, of Brigham and Women’s Hospital in Boston, presented the first report of the TRILOGY ACS Angiographic Cohort study.

For the overall TRILOGY ACS trial, published in the New England Journal of Medicine, researchers randomized 9,326 patients with unstable angina or NSTEMI on aspirin to either prasugrel or clopidogrel. The results showed that prasugrel does not reduce the frequency of ischemic events compared with clopidogrel.

For the prespecified substudy, researchers sought to assess the outcomes of subjects triaged to medical therapy with (n=3,085) or without (n=4,158) preceding angiography. The substudy showed that patients who underwent angiography prior to randomization had significantly lower rates of CVD/MI/stroke, as well as CVD alone and death (see Figure).

Furthermore, patients who had angiography and received prasugrel (Effient, Daiichi Sankyo/Eli Lilly) had lower rates of MI, stroke and the primary endpoint of CVD, MI, and stroke (see Table). These patients also had a lower risk for multiple ischemic events (HR=0.75; 95% CI 0.58–0.98). However, there was a trend toward higher rates of TIMI major bleeding.

Among the angiography cohort, 1,524 had been randomized to prasugrel and 1,561 to clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi-Aventis); among the cohort without angiography, 2,096 were assigned to prasugrel and 2,062 to clopidogrel.

Wiviott noted the limitations of the study: the inability to make direct comparisons between angiography and no angiography and to infer causality, and that the interaction testing was underpowered.

“Though hypothesis generating, these results are consistent with previous trials and suggest that when angiography is performed and coronary disease is confirmed, the benefits and risks of intensive antiplatelet therapy exist whether medical therapy or PCI is elected,” Wiviott said.