Synergistic action between inhibition of P2Y₁₂/P2Y₁ and P2Y₁₂/thrombin in ADP‐ and thrombin‐induced human platelet activation

Abstract

1 The objective of this study was to investigate if there is a synergistic effect of a combination of P2Y 12 and P2Y 1 inhibition and P2Y 12 and thrombin inhibition, on ADP-and thrombin-induced platelet activation, respectively. The rationale being that these combinations will cause a concurrent inhibition of both Ga q and Ga i signalling. 2 Blood from healthy volunteers was preincubated with AR-C69931MX, a reversible P2Y 12 antagonist; MRS2179, a reversible P2Y 1 antagonist; or melagatran, a direct reversible thrombin inhibitor; alone or in various combinations prior to activation with ADP or thrombin. Platelet function in whole blood was assessed by flow cytometry using the antibody PAC-1 to estimate the expression of active a IIb b 3 (the fibrinogen receptor GPIIb/IIIa). A synergistic effect was evaluated by comparing the concentrations in the different combinations with those of corresponding equipotent concentrations of each single inhibitor alone. The equipotent single concentrations were experimentally obtained from concentration response curves performed in parallel. 3 A synergistic effect regarding inhibition of ADP-induced platelet activation (10 mM) was obtained with different combinations of AR-C69931MX and MRS2179. 4 Inhibition of thrombin-induced platelet activation (2 nM) with combinations of AR-C69931MX and the thrombin inhibitor melagatran did also result in a strong synergistic effect. 5 To our knowledge, this is the first time that data supporting a synergistic effect has been published for the inhibitor combinations described. 6 Whether this synergistic effect in vitro also results in an improved antithrombotic effect in vivo with or without an increased risk of bleeding remains to be studied in well-conducted clinical studies.

SCH 602539, a Protease-Activated Receptor-1 Antagonist, Inhibits Thrombosis Alone and in Combination With Cangrelor in a Folts Model of Arterial Thrombosis in Cynomolgus Monkeys

“…The presence of a synergistic effect, resulting from the combined administration of a P2Y 12 antagonist with the direct thrombin inhibitor melagatran, has been previously described. 23 There are 2 possible explanations for this synergism. The first is via the concurrent inhibition of the G protein-coupled …”

Pathophysiology and Therapeutic Potential of Purinergic Signaling

“…There are genetic variations in P2Y 1 and P2Y 12 receptor gene sequences in healthy subjects that explain variations in the platelet response to ADP; this may reflect individual variation in atherothrombotic risk and the efficacy of purinergic antithrombotic drugs (Fontana et al, 2003;Hetherington et al, 2004). A recent study has shown that there is a synergistic inhibition of ADP-induced platelet activation via P2Y 1 and P2Y 12 receptors and for thrombin and P2Y 12 inhibition; it is suggested that there may be clinical benefit by combining these inhibitors, providing that bleeding problems do not outweigh this benefit (Nylander et al, 2004). Postoperative carotid thrombosis is a significant risk for stroke; it seems likely that clopidogrel or ticlopidine may provide an avenue for targeted antiplatelet therapy following vascular intervention (Hayes et al, 2003).…”

Structure of the human P2Y12 receptor in complex with an antithrombotic drug

“…P2Y 12 R, a member of the P2Y purinergic GPCR family stimulated by adenosine diphosphate (ADP), is a major player in platelet aggregation and granule secretion and supports the formation of a thrombus 9 . Ethyl 6-(4-((benzylsulphonyl)carbamoyl)piperidin-1-yl)-5-cyano-2-methylnicotinate (AZD1283) (Extended Data Fig.…”