Tinzaparin for Primary Treatment and Extended Secondary Prophylaxis of Venous Thromboembolism in Patients With Cancer

Inclusion Criteria: * Diagnosis of active cancer * Patients have documented or recurrent malignancy and must meet at least one of the following criteria: * Diagnosis or documented presence of cancer within 6 months, excluding squamous cell or basal cell carcinoma of the skin OR * Receive any therapy for cancer within the previous 6 months OR * Currently receiving any treatment (surgery, radiation, chemotherapy, hormonal therapy, biotherapy, palliative therapy, and/or combined modality therapy) for cancer * Documented first venous thromboembolic event * Patients must meet at least one of the following criteria: * Deep vein thrombosis of the lower extremity confirmed with duplex ultrasonography, magnetic resonance imaging, or venogram OR * Pulmonary embolism confirmed with high probability V/Q scan, CT angiogram, or pulmonary angiogram * ECOG performance status of 0, 1, or 2 * Signed written informed consent * Age 18 years or greater Exclusion Criteria: * Body weight less than 40 kg * Recurrent spontaneous fractures unrelated to the underlying active malignancy * Administration of therapeutic doses of unfractionated or low molecular weight heparin for more than 48 hours prior to registration Amendment 3 (05/26/2009) 11 * Need for long-term oral anticoagulant therapy (e.g., mechanical heart valves, atrial fibrillation) * Poor performance status with an ECOG score of 3 or 4 * Serious hemorrhage requiring hospitalization, transfusion, or surgical intervention within 2 weeks of presentation * Known acute (symptomatic or active bleeding) gastroduodenal ulcer * Epidural/spinal puncture within the last 24 hours * Neurosurgery within 1 week of registration or any previous history of intracranial hemorrhage * Septic endocarditis * Overt pericardial effusion * Current platelet count of less than 50 x 109/L * Undergoing high dose chemotherapy for peripheral blood stem cell or bone marrow transplantation, induction chemotherapy for acute leukemia, or has other conditions associated with persistent thrombocytopenia of less than 100 109/L for a duration of at least four consecutive weeks * Familial bleeding diathesis * Uncontrolled hypertension despite antihypertensive therapy * Dependent upon renal dialysis or significant renal failure with a serum creatinine of greater than three times the upper limit of normal * Allergy to heparin (unfractionated or low molecular weight) * Allergy to contrast medium * Pregnant or of childbearing potential and not using adequate contraception * Geographically inaccessible for follow-up * Failure or inability to give informed consent