title: A randomized clinical trial comparing point-of-care platelet function assays and bleeding time in healthy subjects treated with aspirin or clopidogrel.
abstract: Traditional assays of the coagulation status of patients, bleeding time assessment (BT) and light transmission aggregometry (LTA), are useful in clinical drug development. However, these assays are both labor intensive and expensive. BT results can be operator dependent and by its nature can inhibit subject enrollment in a clinical trial. The preparation of platelet-rich plasma necessary for LTA requires specialized training and laboratory support. Alternatives to these methods are desirable. The goal of this study was identification of a quantitative, easy-to-use, point-of-care device with minimal technical variables that could facilitate assessment of platelet aggregation in clinical drug development. This was a double-blind, placebo-controlled, randomized, three-period cross-over study in healthy volunteers designed to compare the abilities of BT, LTA, and three point-of-care devices, Multiplate®, Platelet Function Analyzer-100®, and VerifyNow® to quantitate the effects on platelet function of 3 days of treatment with aspirin, clopidogrel, or placebo. The effect size (difference in treatment means divided by the pooled standard deviations [SD]) of the three point-of-care devices was greater than or similar to BT and LTA for all treatment comparisons examined. VerifyNow® had the highest effect size comparing ASA to placebo. Multiplate® had the highest effect size comparing clopidogrel to placebo. From this study, we conclude that any one of the three simple-to-use point-of-care devices can reliably assess the treatment effect of ASA and CLP on platelet function in comparison with BT or LTA at the study population level
authors.affiliation: Merck Research Laboratories, Rahway, NJ 07065-0900, USA. fabian_chen@merck.com
authors.forename: Fabian
authors.initials: F
authors.lastname: Chen
authors.forename: Victor
authors.initials: V
authors.lastname: Maridakis
authors.forename: Edward A
authors.initials: EA
authors.lastname: O'neill
authors.forename: Chan
authors.initials: C
authors.lastname: Beals
authors.forename: Waldemar
authors.initials: W
authors.lastname: Radziszewski
authors.forename: Inge
authors.initials: I
authors.lastname: de Lepeleire
authors.forename: Kristien
authors.initials: K
authors.lastname: Van Dyck
authors.forename: Marleen
authors.initials: M
authors.lastname: Depré
authors.forename: James A
authors.initials: JA
authors.lastname: Bolognese
authors.forename: Jan
authors.initials: J
authors.lastname: de Hoon
authors.forename: Marc
authors.initials: M
authors.lastname: Jacquemin
mesh_terms: D000328:Adult; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics; D001241:Aspirin / Q000008:administration & dosage*; D001760:Bleeding Time; D000077144:Clopidogrel; D018592:Cross-Over Studies; D065731:Cytochrome P-450 CYP2C19; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D010979:Platelet Function Tests; D019095:Point-of-Care Systems; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D055815:Young Adult
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19; D013988:Ticlopidine; D001241:Aspirin