Apixaban for the Acute Treatment of Venous Thromboembolism in Children

• Drug: Apixaban
  
  Tablet or Solution
• Drug: Standard of Care
  
  Unfractionated heparin, low molecular weight heparin, and/or a vitamin K antagonist.

• Experimental: Apixaban
  
  Subjects between 3 month to <18 years will be dosed on a body weight tiered regimen. Subjects > or = 35 kg will receive 10 mg twice daily for 7 days followed by 5 mg twice daily thereafter;<35 kg to 25 kg will receive 8 mg twice daily for 7 days followed by 4 mg twice daily thereafter; <25 to 18 kg will receive 6 mg twice daily for 7 days and then 3mg twice daily thereafter; <18 to 12 kg will receive 4 mg twice daily for 7 days and then 2 mg twice daily thereafter; <12 to 9 kg will receive 3 mg twice daily for 7 days and then 1.5 mg twice daily thereafter; <9 kg to 6 kg will receive 2 mg twice daily for 7 days and 1 mg twice daily thereafter.
  Intervention: Drug: Apixaban
• Active Comparator: Standard of Care
  
  Subjects will receive a dose and dosing regimen of anticoagulation treatment based on usual and customary care per local practices.
  Intervention: Drug: Standard of Care

Inclusion Criteria:

1. 3 months to <18 years of age with a minimum weight of 6 kg at the time of randomization.
2. Presence of an index VTE which is confirmed by imaging.
3. Intention to manage the index VTE with anticoagulation treatment for at least 12 weeks.

Exclusion Criteria:

1. Anticoagulant treatment for the index VTE for greater than 7 days prior to randomization.
2. Thrombectomy, thrombolytic therapy, or insertion of a caval filter to treat the index VTE.
3. A mechanical heart valve.
4. Active bleeding or high risk of bleeding at the time of randomization.
5. Intracranial bleed, including intraventricular hemorrhage, within 3 months prior to randomization.
6. Abnormal baseline liver function at randomization.
7. Inadequate renal function at the time of randomization.
8. Platelet count <50×109 per L at randomization.
9. Uncontrolled severe hypertension at the time of randomization.
10. Use of prohibited concomitant medication at the time of randomization.
11. Female subjects who are either pregnant or breastfeeding a child.