Rivaroxaban Plasma Concentrations Cannot be Predicted from Coagulation Assays: Real-Life Experience From a Tertiary Hospital in New Zealand

There was a wide range of measured rivaroxaban concentrations, reflecting the diversity of indications for measurement, with a significant minority associated with subsequent changes in rivaroxaban dosing. Given the frequency of altering dosing regimens based on the results, future efforts should focus on the correlation of concentration data with clinical endpoints to determine reference ranges. An accurate mathematical model to determine rivaroxaban concentrations based on coagulation screening assays could not be developed.