Study APVO101-903 is a Phase 3/4, single arm, open-label clinical trial. The purpose of the study is to evaluate pharmacokinetics (PK), safety, and efficacy of APVO101 prophylaxis in severe or moderately severe hemophilia B subjects < 12 years of age. The study is designed to gather information in two age groups of previously treated (with a minimum of 50 previous ED to factor IX replacement therapy) pediatric patients, specifically those < 6 years of age and 6 to <12 years of age.~Study APVO101-903 consists of three distinct phases:~PK Phase - PK evaluation will consist of administration of a single 75 ± 5 IU/kg dose, followed by factor IX activity and safety assessments up to 50 hours post-infusion.~Treatment Phase - subjects will receive APVO101 prophylaxis (starting prophylaxis dose to be determined based on APVO101 recovery; ideally within the recommended dose range: 35 - 75 IU/kg; twice weekly) for 50 ED (approximately 6 months).~Continuation Phase - subjects may continue to receive APVO101 prophylaxis (recommended dose range: 35 - 75 IU/kg; twice weekly) for an additional ≥ 50 ED.
Phase 3/4, single arm, open-label study to evaluate PK, safety, and efficacy of APVO101 prophylaxis in severe or moderately severe hemophilia B subjects < 12 years of age.