Continuous Clopidogrel Dose Adjustment in Acute Coronary Syndrome Patients With High On-treatment Platelet Reactivity
Condition: Acute Coronary Syndrome
MeSH terms: Acute Coronary Syndrome; Syndrome
Study type: Interventional
Phase: Phase 4

Summary: 
      The purpose of this study is to determine whether continuous clopidogrel dose adjustment
      targeted after platelet function testing improves outcomes during 12 months of follow-up in
      acute coronary syndrome patients treated with coronary artery stenting and with determined
      high platelet reactivity on clopidogrel.
    

Detailed description: 
      Dual antiplatelet therapy (DAPT) with aspirin and P2Y12 receptor antagonists during 12 months
      presents cornerstone treatment in acute coronary syndrome (ACS) patients undergoing
      percutaneous coronary intervention (PCI). Clopidogrel is the most widely used P2Y12 inhibitor
      despite it's limitations that include highly variable P2Y12-receptor inhibition which causes
      wide interindividual platelet reactivity variability. Since high on-treatment platelet
      reactivity (HTPR) on clopidogrel is strongly associated with adverse events, antiplatelet
      therapy tailoring has been vastly investigated to determine whether individualized approach
      could improve outcomes. In the time of progressive personalized approach to therapy,
      effective strategies are needed to minimize the risk of ischemic adverse events without
      increasing the risk for bleeding.

      Aim of this study is to investigate whether continuous clopidogrel dose adjustment according
      to platelet function testing (PFT) using Multiplate® function analyzer (Roche Diagnostics,
      Mannheim, Germany) could decrease the rate of adverse events in ACS patients treated with PCI
      and with HTPR during early and late period of DAPT treatment.

      Cut off values for HTPR and enhanced platelet response were set according to the consensus
      statement at >46 U and <19 U, respectively. PFT and therapy tailoring was performed at day 1,
      2, 3, 7, 30 and month 2, 3, 6, 9 and 12.
    

Intervention name(s): Clopidogrel dose adjustment
Intervention type(s): Drug
Intervention description(s): Patients in the interventional arm will receive clopidogrel dose adjustment to maintain optimal platelet reactivity determined by Multiplate function analyzer (19-46U).
They will undergo platelet function testing on day 1,2,3,7,30 and month 2,3,6,9 and 12.
On first two measurements patients will receive up to 2 additional clopidogrel loading doses (600 mg) and put on 150 mg and 75 mg a day if platelet reactivity >18U and <18U, respectively. Maintenance dose will be determined on following measurements - increased by 75 mg if >46U; not changed if 19-46U; decreased by 75 mg if <19U. Minimal dose - 75 mg; maximal dose 300 mg (for patients >70 years 150 mg)
Other intervention name(s): antiplatelet therapy tailoring
Intervention MeSH terms: Clopidogrel
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: clopidogrel; platelet reactivity; acute coronary syndrome; tailoring therapy; outcome