In Vitro Reversal of the Anti-Aggregant Effect of Ticagrelor Using Untreated Platelets

Area of Science:

• Cardiovascular Medicine
• Hematology
• Pharmacology

Background:

• Ticagrelor is an anti-platelet medication used to prevent thrombosis in acute coronary syndrome and after stent implantation.
• Ticagrelor use is associated with an increased risk of bleeding.
• Platelet transfusions may mitigate bleeding risks but optimal protocols are undefined.

Purpose of the Study:

• To evaluate the efficacy of platelet transfusion in reversing ticagrelor's anti-platelet effects in vitro.
• To determine the optimal quantity and timing of platelet administration for reversing ticagrelor's effects.

Main Methods:

• Ten healthy subjects received ticagrelor and aspirin for 5 days.
• Blood samples were collected at various time points post-treatment.
• Adenosine diphosphate-mediated platelet aggregation was measured after mixing subject and donor platelet-rich plasma in vitro.

Main Results:

• The anti-aggregant effect of ticagrelor spontaneously resolved by 72 hours after the last dose.
• Donor platelets enhanced the reversal of ticagrelor's effect.
• Six apheresis platelet units achieved 50% reversal at 10 hours and >90% reversal at 24 hours.

Conclusions:

• In vitro studies show donor platelets can reverse ticagrelor's anti-platelet activity.
• Clinically relevant platelet doses partially and nearly fully reversed ticagrelor's effects at 10 and 24 hours, respectively.
• Findings support the potential use of platelet transfusions to manage bleeding or facilitate emergency surgery in patients on ticagrelor.