Long-Term Efficacy and Safety of Damoctocog Alfa Pegol Prophylaxis in Patients with Haemophilia A Aged 12-<18 Years at Enrolment into PROTECT VIII

Introduction: The phase 2/3 PROTECT VIII study demonstrated long-term efficacy and safety of damoctocog alfa pegol (BAY 94-9027; Jivi®), a B-domain-deleted recombinant factor VIII (FVIII), site-specifically PEGylated to improve its pharmacokinetic profile. We report a post hoc assessment of bleeding and safety outcomes in the subgroup of patients, aged 12-<18 years at enrolment. Method: PROTECT VIII was a multicentre, open-label study of previously treated males aged 12-65 years with severe haemophilia A (FVIII <1%). Twelve patients were included in this analysis. All received damoctocog alfa pegol prophylaxis for the total time in study (median [range] time in study 4.0 [1.3-6.2] years). Results: Overall median (Q1; Q3) total and joint annualised bleeding rates were 1.8 (0.4; 5.1) and 0.7 (0.2; 1.8), respectively, for the entire study. During the last 6 months of treatment, eight (66.7%) and ten (83.3%) out of 12 patients experienced zero total and joint bleeds, respectively. No patient developed FVIII inhibitors. No deaths or thrombotic events were reported. Conclusion: Efficacy and safety of damoctocog alfa pegol were confirmed in adolescent patients with haemophilia A, with data for up to 6 years supporting its use as a long-term treatment option in this group as they transition into adulthood.