Safety and Efficacy of Therapeutic Anticoagulation With Tinzaparin During Pregnancy Via Weight-based Dosing

University of Calgary

Status and phase: Completed; Phase 4

Conditions: Venous Thromboembolism

Treatments: Drug: Tinzaparin

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT00851864

05161977

Details and patient eligibility

About

The purpose of this study is to evaluate the safety and efficacy of therapeutic anticoagulation with tinzaparin during pregnancy via weight-based dosing.

Full description

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.

Enrollment: 13 patients

Sex: Female

Ages: 18 to 45 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Singleton pregnancies in women over the age of 18 requiring anticoagulation for acute VTE (DVT/PE), or high-risk prophylaxis at a tinzaparin dose of 175 IU/kg.
• High-risk patients include those with multiple (two or more) episodes of VTE and/or women receiving long-term anticoagulants (e.g. single event with known thrombophilia; APLAs and history of venous thrombosis)

Exclusion criteria

• Multiple gestation\
• Prosthetic valves
• Active bleeding or other contraindication to anticoagulation therapy
• Allergy to heparin, bisulfites, or fish, history of HIT (heparin induced thrombocytopenia), severe hypertension (diastolic >130)
• Severe hepatic or renal failure
• Patients over 100kg.

Trial design

13 participants in 1 patient group

A

Experimental group

Description:

Women requiring therapeutic anticoagulation, singleton pregnancy,\<30weeks

Treatment:

Drug: Tinzaparin