Randomized, Double-Blind, Active Comparator Pharmacodynamic Study of Platelet Inhibition with Crushed and Integral Formulations of Clopidogrel and Ticagrelor in Acute Coronary Syndrome

Background: Crushed formulations of specific antiplatelet agents produce earlier and stronger platelet inhibition. We studied the platelet inhibitory effect of crushed clopidogrel in patients with acute coronary syndrome (ACS) and its relative efficacy compared with integral clopidogrel, crushed and integral ticagrelor.

Objectives: We aimed to compare the platelet inhibitory effect of crushed and integral formulations of clopidogrel and ticagrelor in patients with acute coronary syndrome (ACS).

Methods: Overall, 142 patients with suspected ACS were randomly assigned to receive crushed or integral formulations of clopidogrel or ticagrelor. Platelet inhibition at baseline and 1 and 8 h was assessed using the VerifyNow assay. High on-treatment platelet reactivity (HTPR) ≥ 235 P2Y₁₂ reaction units (PRUs) 1 h after the medication loading dose was also determined.

Results: The PRU and percentage inhibition median (interquartile range) at 1 h for the different formulations were as follows: crushed clopidogrel: 196.50 (155.50, 246.50), 9.36 (- 1.79, 25.10); integral clopidogrel: 189.50 (159.00, 214.00), 2.32 (- 2.67, 19.89); crushed ticagrelor: 59.00 (10.00, 96.00), 75.53 (49.12, 95.18); and integral ticagrelor: 126.50 (50.00, 168.00), 40.56 (25.59, 78.69). There was no significant difference in PRU or percentage platelet inhibition between the crushed and integral formulations of clopidogrel (p = 0.990, p = 0.479); both formulations of ticagrelor were superior to the clopidogrel formulations (p < 0.05). On paired comparison, crushed ticagrelor showed robust early inhibition of platelets compared with the integral formulation (p = 0.03). Crushed clopidogrel exhibited the maximal HTPR of 34.3%, but was < 3% for both formulations of ticagrelor.

Conclusions: The platelet inhibitory effect of crushed clopidogrel is not superior to integral preparation in patients with ACS. Crushed ticagrelor produced maximal platelet inhibition acutely. HTPR rates in ACS are similar and very low with both formulations of ticagrelor, and maximal with crushed clopidogrel. Clinical Trials Registry of India identifier number CTRI/2020/06/025647.