Prolongation of the Interval Between Prothrombin Time Tests in Stable Patients II (PRINT-II)
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|ClinicalTrials.gov Identifier: NCT01654042|
Recruitment Status : Withdrawn (No funding obtained)
First Posted : July 31, 2012
Last Update Posted : March 20, 2014
|Condition or disease||Intervention/treatment||Phase|
|Atrial Fibrillation Valvular Heart Disease Deep Vein Thrombosis Pulmonary Embolism Peripheral Arterial Disease||Other: Prolonged interval between PT testing||Phase 3|
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||0 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||None (Open Label)|
|Official Title:||Prolongation of the Interval Between Prothrombin Time Tests in Stable Patients II (the PRINT II Study): a Randomized Controlled, Non-inferiority Trial Comparing 4-weekly With 12-weekly Testing and Dose-assessment|
|Study Start Date :||April 2014|
|Estimated Primary Completion Date :||April 2018|
|Estimated Study Completion Date :||October 2018|
No Intervention: Standard interval between PT testing
Prothrombin time (PT) is tested every 4 weeks, according to American College of Chest Physicians (ACCP) Guidelines up to 2008 for stable patients on warfarin.
Experimental: Prolonged interval between PT testing
Prothrombin time (PT) is tested every 12 weeks, according to suggestion in American College of Chest Physicians (ACCP) Guidelines of 2012 for stable patients on warfarin.
Other: Prolonged interval between PT testing
Patients in the intervention group will be scheduled for prothrombin time testing and dosing of warfarin every 12 weeks instead of every 4 weeks. This has been suggested in the latest edition of the ACCP guidelines as a possibility for very stable patients. In order to change this from a suggestion to a formal recommendation a study powered for clinically important outcomes is needed.
Other Name: INR (International Normalized Ratio) tests
- Composite of major bleeding and objectively verified arterial or venous thromboembolism [ Time Frame: Average 3 years ]The justification for a composite outcome including both bleeding and thromboembolism is that the study is not reflecting a "trade-off" scenario where one regimen is expected to be more effective at the cost of increased harm compared to the other regimen. Conversely, the potential disadvantage of the experimental regimen in this trial is increased variability in prothrombin time, which may result in an increased rate of short as well as long prothrombin times and therefore potentially an increase of both types of clinical events.
- All-cause mortality [ Time Frame: Average 3 years ]
- Any bleeding [ Time Frame: Average 3 years ]This is the composite of major and minor bleeding
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01654042
|Hamilton Health Sciences - General Hospital|
|Hamilton, Ontario, Canada, L8L 2X2|
|Principal Investigator:||Sam Schulman, MD, PhD||McMaster University|