title: Evaluation of the prothrombin time for measuring rivaroxaban plasma concentrations using calibrators and controls: results of a multicenter field trial.
abstract: This study evaluated the prothrombin time (PT) assay for the measurement of plasma concentrations of rivaroxaban using calibrators and controls. The intra- and interlaboratory precision of the measurement was investigated in a field trial involving 21 laboratories. Each laboratory was provided with rivaroxaban calibrators and control plasma samples containing different concentrations of rivaroxaban, and PT reagents. The evaluation was carried out over 2 consecutive weeks using centrally provided and local PT reagents. A calibration curve was produced each day (for inter-run precision), and day-to-day precision was evaluated by testing 3 control plasma samples. A large interlaboratory variation (in seconds) was observed with local PT reagents. The results were less variable when expressed as rivaroxaban concentrations (ng/mL) or when central PT reagent was used (STA Neoplastine CI Plus). The widely available PT assay, in conjunction with rivaroxaban calibrators, may be useful for the measurement of peak plasma levels of rivaroxaban.
authors.affiliation: Hôtel-Dieu University Hospital, Paris, France. meyermichel.samama@biomnis.com
authors.forename: Meyer Michel
authors.initials: MM
authors.lastname: Samama
authors.forename: Genevieve
authors.initials: G
authors.lastname: Contant
authors.forename: Theodore E
authors.initials: TE
authors.lastname: Spiro
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Perzborn
authors.forename: Lena Le
authors.initials: LL
authors.lastname: Flem
authors.forename: Céline
authors.initials: C
authors.lastname: Guinet
authors.forename: Yves
authors.initials: Y
authors.lastname: Gourmelin
authors.forename: Jean Luc
authors.initials: JL
authors.lastname: Martinoli
mesh_terms: D000925:Anticoagulants / Q000097:blood* / Q000494:pharmacology; D001793:Blood Preservation; D002138:Calibration; D016903:Drug Monitoring / Q000295:instrumentation / Q000379:methods*; D004355:Drug Stability; D005060:Europe; D015942:Factor VIIa / Q000494:pharmacology; D005240:Feasibility Studies; D005612:Freeze Drying; D006801:Humans; D007202:Indicators and Reagents; D059021:Laboratory Proficiency Testing; D009025:Morpholines / Q000097:blood* / Q000494:pharmacology; D009656:North America; D009994:Osmolar Concentration; D010949:Plasma; D011517:Prothrombin Time / Q000379:methods*; D015203:Reproducibility of Results; D000069552:Rivaroxaban; D012680:Sensitivity and Specificity; D013876:Thiophenes / Q000097:blood* / Q000494:pharmacology
chemical_list: D000925:Anticoagulants; D007202:Indicators and Reagents; D009025:Morpholines; D013876:Thiophenes; D000069552:Rivaroxaban; D015942:Factor VIIa