Evaluation of Maintenance Dosing vs Loading Dosing Upon Restarting Warfarin Therapy: A Prospective Randomized Trial

2014-08-27 03:13:40 | BioPortfolio


A prospective, randomized trial to compare the time taken to achieve a therapeutic INR upon re-starting warfarin at a "loading" dose (namely 1.5 times the "maintenance" dose for 3 days) compared to the known "maintenance" dose.


Patients will be identified via the University of Alberta Hospital Anticoagulation Management Service. Following the receipt of written, informed consent, patients will be randomized to re-start warfarin at their "maintenance" dose or at a "loading" dose (1.5 times the maintenance dose for 3 days, then resumption of warfarin dosing as per the maintenance dose). Randomization will be performed on-line through the EPICORE Centre.

Assuming Day 1 is the day warfarin is re-started, patients will have INRs done on day 3 and at least every 2 days thereafter until a therapeutic INR is obtained. In addition, protein C, protein S and factor II levels will be obtained while the patient is on stable maintenance dosing of warfarin (i.e., prior to holding warfarin for the procedure), 7 days after re-starting warfarin, and 14 days after re-starting warfarin. Complete blood counts (CBCs) will be done with each INR if the patient is taking a low molecular weight heparin (LMWH). Patients will have their anticoagulant therapy managed by the AMS for 6 weeks and will receive a telephone follow-up by the AMS at 90 days to determine if any bleeding or clotting complications occurred.

Study Design

Allocation: Randomized, Control: Dose Comparison, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment




warfarin, Warfarin


Univeristy of Alberta
T6G 2C8


Not yet recruiting


University of Alberta

Results (where available)

View Results


Published on BioPortfolio: 2014-08-27T03:13:40-0400

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