Pivotal Study (Pharmacokinetics, Efficacy, Safety) of BAX 326 (rFIX) in Hemophilia B Patients

Recombinant Factor IX (BAX 326): A Phase 1/3, Prospective, Controlled, Multicenter Study Evaluating Pharmacokinetics, Efficacy, Safety and Immunogenicity in Previously Treated Patients With Severe or Moderately Severe Hemophilia B

The purpose of this pivotal Phase 1/3 study is to determine the pharmacokinetic (PK) parameters, the hemostatic efficacy, and the safety of BAX 326, a recombinant factor IX, in previously treated patients (PTPs) with severe and moderately severe hemophilia B.

Main Inclusion Criteria:

• Participant is 12 to 65 years old at the time of screening
• Participant and/or legal representative has/have provided signed informed consent
• Participant has severe (factor IX (FIX) level < 1%) or moderately severe (FIX level 1-2%) hemophilia B (based on the one stage activated partial thromboplastin time (aPTT) assay), as tested at screening at the central laboratory
• Participant is previously treated with plasma-derived or recombinant FIX concentrate(s) for a minimum of 150 exposure days (EDs) (based on the participant's medical records); if a verifiable, documented history is unavailable, the participant can be enrolled if s/he has 100-150 EDs to any FIX product that are not fully documented and has participated in Study 050901 for at least 50 EDs to Immunine prior to enrollment (not valid for US and Japan).
• Participant has no evidence of a history of FIX inhibitors
• If the participant is to receive prophylactic treatment, the participant is willing to receive prophylactic treatment over a period of 6 months.
• If the participant is to receive on-demand treatment, the participant has ≥12 documented bleeding episodes requiring treatment within 12 months prior to enrollment and is willing to receive on-demand treatment for the duration of this study.

Main Exclusion Criteria:

• The participant has a history of FIX inhibitors with a titer ≥0.6 Bethesda Units (BU) (as determined by the Nijmegen modification of the Bethesda assay or the assay employed in the respective local laboratory) at any time prior to screening
• The participant has a detectable FIX inhibitor at screening, with a titer ≥0.6 BU as determined by the Nijmegen modification of the Bethesda assay in the central laboratory
• The participant's weight is < 35 kg or > 120 kg
• The participant has a history of allergic reaction, eg, anaphylaxis, following exposure to FIX concentrate(s)
• The participant has a known hypersensitivity to hamster proteins or recombinant furin (rFurin)
• The participant has ongoing or recent evidence of a thrombotic disease, fibrinolysis or disseminated intravascular coagulation (DIC)