Safety and Efficacy of Therapeutic Anticoagulation With Tinzaparin During Pregnancy Via Weight-based Dosing
The purpose of this study is to evaluate the safety and efficacy of therapeutic anticoagulation with tinzaparin during pregnancy via weight-based dosing.
|Study Design:||Endpoint Classification: Safety/Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
|Official Title:||Weight-Adjusted Dosing of Tinzaparin in Pregnancy|
- Rate of anti-Xa levels falling outside the target range of 0.4-1.2IU/mL [ Time Frame: anti-Xa level Day 1,28, then q4 weeks ] [ Designated as safety issue: Yes ]
- mean dosage requirement in each trimester [ Time Frame: 1 year ] [ Designated as safety issue: No ]
- rate of clinical outcomes (PE/DVT) - objective testing of DVT/PE from radiology [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
|Study Start Date:||October 2007|
|Study Completion Date:||May 2011|
|Primary Completion Date:||October 2010 (Final data collection date for primary outcome measure)|
Women requiring therapeutic anticoagulation, singleton pregnancy,<30weeks
LMWH (tinzaparin-Innohep, Leo Pharma A/S) 175 anti-factor Xa units per kilogram of body weight sub-cutaneously once daily.
Treatment will be done for the duration of the pregnancy.
Other Name: innohep
Physicians in the Calgary Health Region are using tinzaparin (predominantly) and other low molecular weight heparins (LMWHs) for the treatment venous thromboembolism (VTE) in pregnancy. The most recent anticoagulation guidelines from American College of Chest Physicians (ACCP) suggest that heparin levels (anti-Factor-Xa activity levels) may be done periodically through pregnancy to determine the need to adjust the dose of LMWH as pregnancy progresses. This monitoring is widely practiced. There is no clear consensus in the literature, however, with some experts suggesting that initial and subsequent dosing may be done based on weight alone (as is done in the non-pregnant population). Given the multiple physiologic changes which occur to drug metabolism during pregnancy, this bears further evaluation. To date, there is very limited data on weight-adjusted dosing of LMWH in pregnancy. This study is therefore designed to determine if dosing of tinzaparin during pregnancy based on weight, with periodic weight-based adjustments, will result in adequate therapeutic anticoagulation.
|Calgary Health Region|
|Calgary, Alberta, Canada, T2N 4N1|
|Principal Investigator:||Paul Gibson, M.D. FRCPC||University of Calgary|
|Study Chair:||Kendra Newell, M.D.||University of Calgary|
|Study Chair:||David Sam, M.D. FRCPC||University of Calgary|