Ticagrelor more effective than clopidogrel for ad-hoc PCI

SAN DIEGO — Troponin-negative patients with ACS undergoing ad-hoc PCI had greater, more rapid reductions in platelet reactivity after treatment with ticagrelor compared with clopidogrel, according to results of a pharmacodynamics study presented at the Society for Cardiovascular Angiography and Interventions Scientific Sessions.

Researchers randomly assigned 100 troponin-negative, low-risk adults (mean age, 60 years) with progressive, unstable angina to a 180-mg loading dose of ticagrelor (Brilinta, AstraZeneca; n = 51) or 600-mg loading dose of clopidogrel (n = 49) with aspirin at the time of PCI.

Platelet reactivity was measured by VerifyNow prior to the loading dose, at 0.5, 2 and 8 hours after, and upon completion of PCI. Major adverse coronary and CV events were also assessed at 30 days.

The primary endpoint was platelet reactivity at 2 hours following the loading dose as measured by P2Y12 reaction units (PRU).

Patients assigned ticagrelor had significantly lower platelet reactivity at 2 hours compared with patients assigned clopidogrel (PRU 98.4 vs. 257.5; P < .001). PRU diverged between the groups within 30 minutes of administration, with the difference achieving significance at completion of PCI (mean, 0.6 hours) and persisting for up to 8 hours after the loading dose (P < .001).

The researchers also noted that high on-treatment platelet reactivity, which has been associated with risk for ischemic events, was significantly less common among patients assigned ticagrelor (13.3% of patients at 2 hours vs. 78.3%; P < .001).

In other results, ticagrelor was well tolerated and no notable safety findings, as assessed by adverse events, bleeding events, physical examination and vital signs, emerged.

Roxana Mehran

"In low-risk ACS patients undergoing ad-hoc PCI, platelet reactivity ... decreased to a greater degree and extent at 2 hours with ticagrelor compared with clopidogrel, and this was maintained all the way out to 8 hours, with no variability whatsoever,” Roxana Mehran, MD, FSCAI, director of cardiovascular research and interventional clinical trials at Mount Sinai Medical Center and Cardiology Today’s Intervention associate medical editor, said during a press conference. “These findings suggest that ticagrelor may be more effective than clopidogrel … in low-risk, troponin-negative patients, and its clinical implications will need to be tested in a larger population.” – by Adam Taliercio

Reference:

Mehran R, et al. Late-Breaking Clinical Trials. Presented at: Society for Cardiovascular Angiography and Interventions Scientific Sessions: May 6-9, 2015; San Diego.

Disclosure: Mehran reports receiving research grants from AstraZeneca, Bristol-Myers Squibb/Sanofi-Aventis, Daiichi Sankyo/Eli Lilly and The Medicines Company and receiving advisory board/consultant fees from Abbott Laboratories, AstraZeneca, Bayer, Boston Scientific, Covidien, CSL Behring, Janssen Pharmaceuticals, Merck, Osprey Medical Inc., Regado Biosciences, Sanofi-Aventis, The Medicines Company and Watermark Consulting.