Efficacy, safety and bioequivalence of the human-derived B-domain-deleted recombinant factor VIII TQG202 for prophylaxis in severe haemophilia A patients

Abstract

Introduction: Current treatment of severe haemophilia A includes prophylaxis with factor VIII (FVIII) replacement. The supply of plasma-derived FVIII is short in China. Purpose: To evaluate the efficacy and safety of a new B-domain deleted (BDD) recombinant FVIII (TQG202) produced by human-derived cells for prophylaxis in severe haemophilia A patients and compare the bioequivalence with Xyntha. Methods: This multicentre, clinical trial consisted of an open-label, randomized, two-period cross-over trial assessing single-dose pharmacokinetics (PK), and a single-arm clinical trial evaluating the efficacy and safety of 24 weeks of TQG202 prophylaxis, and repeated PK were assessed after prophylaxis phase. The single-dose was 50 IU/kg in PK assessment, and the initial dose was 30 ± 5 IU/kg for prophylaxis. The primary endpoints of prophylaxis were the annualized bleeding rate (ABR) and the incremental recovery rate of the first administration. Adverse events (AEs) were recorded. Results: Twenty-six participants were enrolled in the PK assessment and 81 participants in the prophylaxis phase. Mean age was 25.9 ± 10.8 years and all participants were male. The results of PK assessment showed TQG202 is bioequivalent to Xyntha. The total ABR was 2.0 (95% CI: 1.2–2.9) in prophylaxis phase. The mean incremental recovery rate of the first administration was.027 (95% CI:.026–.028) (IU/ml)/(IU/kg). AEs occurred in 42 participants, with an incidence of 51.9%. One severe AE not related to TQG202 occurred. No participants developed FVIII inhibitors. Conclusion: TQG202 shows bioequivalence with Xyntha. The promising efficacy and tolerability in the severe haemophilia A prophylaxis support the use of TQG202in clinical practice.