Study to Determine the Safety and Efficacy of rFIXFc in Previously Untreated Males With Severe Hemophilia B
Condition: Hemophilia B
MeSH terms: Hemophilia A; Hemophilia B
Intervention: rFIXFc
Intervention description: Adjustments to the dose and interval of rFIXFc was made in this study based on investigator discretion using available pharmacokinetic (PK) data, subsequent FIX trough and peak levels, level of physical activity, and bleeding pattern, in accordance with local standards of care for a prophylactic regimen. There was an option to start study dosing as episodic treatment (on-demand).
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Intervention model: Single Group Assignment
Masking: None (Open Label)
Enrollment: 33.0
Sex: Male
Maximum age: 17 Years
Healthy volunteers: No
Keywords: prophylaxis treatment; episodic treatment

Summary:

      The primary objective of the study was to evaluate the safety of recombinant coagulation
      factor IX Fc fusion protein (rFIXFc, BIIB029) in previously untreated patients (PUPs) with
      severe hemophilia B. Secondary objectives were to evaluate the efficacy of rFIXFc in the
      prevention and treatment of bleeding episodes in PUPs, and to evaluate rFIXFc consumption for
      prevention and treatment of bleeding episodes in PUPs.
    

Eligibility criteria:

        Key Inclusion Criteria:

          -  Weight >=3.5 kilogram at the time of informed consent.

          -  Severe hemophilia B was defined as less than or equal to (<=)2 International Units per
             deciliter (IU/dL) (<=2 percent [%]) endogenous FIX documented in the medical record or
             as tested during the Screening Period.

        Key Exclusion Criteria:

          -  History of positive inhibitor testing. A prior history of inhibitors was defined based
             on a participant's historical positive inhibitor test using the local laboratory
             Bethesda value for a positive inhibitor test (that is equal to or above lower limit of
             detection).

          -  History of hypersensitivity reactions associated with any rFIXFc administration.

          -  Exposure to blood components or injection with a coagulation factor IX (FIX)
             concentrate (including plasma derived) other than rFIXFc.

          -  Injection with commercially available rFIXFc more than 28 days prior to Screening.

          -  More than 3 injections of commercially available rFIXFc prior to confirmation of
             eligibility.

          -  Other coagulation disorders in addition to hemophilia B.

          -  Any concurrent clinically significant major disease that, in the opinion of the
             Investigator, would have made the participant unsuitable for enrollment (example HIV
             infection with cluster of differentiation 4 (CD4) lymphocyte count less than (<)200
             cells/microliter (mcL) or a viral load greater than (>)200 particles/mcL, or any other
             known congenital or acquired immunodeficiency).

          -  Current systemic treatment with chemotherapy and/or other immunosuppressant drugs. Use
             of steroids for treatment of asthma or management of acute allergic episodes or
             otherwise life-threatening episodes was allowed. Treatment in these circumstances
             should not have exceeded a 14-day duration.

          -  Participation within the past 30 days in any other clinical study involving
             investigational treatment.

          -  Current enrollment in any other clinical study involving investigational treatment.

          -  Inability to comply with study requirements.

          -  Other unspecified reasons that, in the opinion of the Investigator or Bioverativ,
             would have made the participant unsuitable for enrollment.

        NOTE: Other protocol-defined inclusion/exclusion criteria may apply.