The first month after a ST-segment elevation myocardial infarction (STEMI) represents the highest-risk period for MACEs following primary PCI. The TADCLOT (Twice-A-Day CLOpidogrel vs Ticagrelor) trial, published in the Journal of the American College of Cardiology, compared ticagrelor with a double-dose clopidogrel regimen during this critical window.

In this double-blind, randomized superiority trial conducted at the National Institute of Cardiovascular Diseases in Karachi, Pakistan, 2,201 patients with STEMI within 24 hours of PCI were assigned 1:1 to receive either ticagrelor (180 mg loading dose, 90 mg twice daily) or double-dose clopidogrel (600 mg loading dose, 75 mg twice daily) for one month.

At 30 days, MACEs occurred in 2.2% of patients receiving ticagrelor and 2.9% receiving clopidogrel (hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.44–1.27, P = 0.28). Cardiovascular death or definite stent thrombosis occurred in 1.9% versus 2.5% (HR 0.77, 95% CI 0.44–1.37). Ticagrelor showed a statistically significant reduction in MACE at 7 days (HR 0.15, P = 0.002) and 14 days (HR 0.46, P = 0.02), but the difference was not maintained by day 30.

Bleeding risk, including Bleeding Academic Research Consortium (BARC) type 2–5 events, was low and comparable between groups (0.5% versus 0.4%). Major bleeding (BARC type 3 or 5) occurred infrequently in both arms.

These findings suggest that ticagrelor offers an early reduction in ischemic events after primary PCI but does not provide a sustained benefit at one month compared with intensified clopidogrel therapy. The results emphasize the need for future studies to refine early-phase antiplatelet strategies following myocardial infarction.