Study of AAV5-hFIX in Severe or Moderately Severe Haemophilia B

A Phase I/IIb Extension Study Assessing the Long-term Safety and Efficacy of an Adeno-associated Viral Vector Containing a Codon-optimized Human Factor IX Gene (AAV5-hFIX) Previously Administered to Adult Patients With Severe or Moderately Severe Haemophilia B During the CT-AMT-060-01 Phase I/II Study

This is an open-label, extension study enrolling patients who have successfully completed all assessments in Study CT-AMT-060-01 (Years 1-5). Assessment phase will begin at Visit 36 (the first clinical visit in this extension study, approximately 5.5 years after the initial dosing visit Study CT-AMT-060-01) and go to Visit 45 (10-years post-dosing in Study CT-AMT-060-01).

Inclusion Criteria:

• - Subjects with congenital hemophilia B who completed Study CTAMT-060-01
• - Able to provide informed consent following receipt of verbal and written
• information about the trial.

Exclusion Criteria:

• - Enrolled subjects will have already been assessed based on the exclusion
• criteria for Study CT-AMT-060-01.