Ticagrelor or prasugrel in patients with acute coronary syndrome with off-hour versus on-hour presentation: a subgroup analysis of the ISAR-REACT 5 trial

Objectives: To assess the efficacy and safety of ticagrelor versus prasugrel in patients with acute coronary syndrome (ACS) presenting during off- and on-hours.

Background: The efficacy and safety of ticagrelor versus prasugrel in patients with ACS according to time of hospital presentation remain unknown.

Methods: This post hoc analysis of the ISAR-REACT 5 trial included 1565 patients with ACS presenting off-hours and 2453 patients presenting on-hours, randomized to ticagrelor or prasugrel. The primary endpoint was a composite of death, myocardial infarction, or stroke; the safety endpoint was Bleeding Academic Research Consortium (BARC) type 3-5 bleeding, both at 12 months.

Results: The primary endpoint occurred in 80 patients (10.4%) in the ticagrelor group and 57 patients (7.3%) in the prasugrel group in patients presenting off-hours (hazard ratio [HR] = 1.45; 95% confidence interval [CI] 1.03-2.03; P = 0.033), and 104 patients (8.5%) in the ticagrelor group and 80 patients (6.7%) in the prasugrel group in patients presenting on-hours (HR = 1.29 [0.97-1.73]; P = 0.085), without significant treatment arm-by-presentation time interaction (P_int = 0.62). BARC type 3 to 5 bleeding occurred in 35 patients (5.1%) in the ticagrelor group and 37 patients (5.3%) in the prasugrel group (P = 0.84) in patients presenting off-hours, and 60 patients (5.9%) in the ticagrelor group and 43 patients (4.6%) in the prasugrel group in patients presenting on-hours (P = 0.17).

Conclusions: In patients with ACS planned to undergo an invasive treatment strategy, time of presentation (off-hours vs. on-hours) does not interact significantly with the relative efficacy and safety of ticagrelor vs. prasugrel.

Clinical trial registration: NCT01944800.