A Phase I/II Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Efficacy of NXT007 in Persons With Severe or Moderate Hemophilia A
WP44714 is a Phase I/II, open-label, non-randomized, global, multicenter trial consisting of two parts: * Part 1 is a multiple-ascending dose (MAD) study in adult and adolescent male participants with severe or moderate hemophilia A with or without factor VIII (FVIII) inhibitors. * Part 2 is a multiple-dose study in pediatric male participants with severe or moderate hemophilia A with or without FVIII inhibitors. The overall aim of the study is to investigate the safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity, and efficacy of NXT007.
• Diagnosis of severe (Factor VIII \[FVIII\] coagulant activity \<1 IU/dL) or moderate (FVIII coagulant activity ≥1 IU/dL and ≤5 IU/dL) congenital hemophilia A with or without inhibitors against FVIII
• Participants with FVIII inhibitors: participants using recombinant activated factor VII (rFVIIa) or willing to switch to rFVIIa as primary bypassing agent for the treatment of breakthrough bleeds, trauma, or procedures
• Historic local FVIII inhibitor test results being available during screening to confirm any previous inhibitor history and current status
• Participants who previously successfully completed immune tolerance induction (ITI) must have done so at least 5 years before screening and must have no evidence of inhibitor recurrence (permanent or temporary) since. FVIII tolerance defined as \<0.6 Bethesda unit (BU)/mL (\<1.0 BU/mL only for laboratories with an historical sensitivity cutoff for inhibitor detection of 1.0 BU/mL) and in vivo recovery \>66%
• Documentation of number and type of bleeding episodes in the last 24 weeks prior to enrollment
• Adequate hematologic function, defined as platelet count ≥100,000 cells/μL and hemoglobin ≥11 g/dL at the time of screening
• Adequate hepatic function defined as total bilirubin ≤1.5× age-adapted upper limit of normal (ULN) (excluding Gilbert syndrome) and both aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤3× age-adapted ULN at the time of screening, and no clinical signs or known laboratory/radiographic evidence consistent with cirrhosis. For patients with Gilbert syndrome, bilirubin should be \<4 mg/dL or 68.4 umol/L at the time of screening.
• For Part 1 only: Adequate renal function, defined as serum creatinine ≤2.5× age-adapted ULN and calculated creatinine clearance ≥30 mL/min by Cockroft-Gault formula
• For Part 2 only: Adequate renal function, defined as serum creatinine ≤1.5× age-adapted ULN. When the serum creatinine is ≥1.5× ULN, creatinine clearance by Bedside Schwartz formula must be \>70 mL/min/1.73m\^2.
• Willingness and ability to comply with schedules visits, treatment plans, laboratory tests, and other study procedures