rFIXFc prophylaxis improves pain and levels of physical activity in haemophilia B: Post hoc analysis of B-LONG using haemophilia-specific quality of life questionnaires.

INTRODUCTION: Recurrent bleeding in severe haemophilia B causes painful hemarthroses and reduces capacity for physical activity. Recombinant factor IX Fc fusion protein (rFIXFc) prophylaxis results in low annualised bleeding rates, with the potential to improve patients' health-related quality of life (HRQoL). AIM: To present a post hoc analysis of data from B-LONG describing change over time in patient-reported outcomes associated with pain and physical activity. METHODS: Patients (≥12 years) who received weekly dose-adjusted or interval-adjusted rFIXFc prophylaxis and completed the Haemophilia-Specific QoL questionnaire for adolescents (Haemo-QoL) or adults (Haem-A-QoL) at baseline (BL) and end of study (EoS). Individual level changes in items of the 'Physical Health' and 'Sports and Leisure' domains, categorised as 'never/rarely/seldom' or 'sometimes/often/all the time', were analysed using McNemar's test to compare distribution of responses at EoS versus BL. RESULTS: At EoS versus BL, a significantly greater proportion of patients did not experience painful swellings (64% vs. 44%; P = .004), painful joints (44% vs. 28%; P = .003) or pain when moving (54% vs. 41%; P = .026). Additionally, at EoS versus BL, patients were less likely to avoid participating in sports like football (30% vs. 8%; P = .002), avoid sports due to their haemophilia (47% vs. 27%; P = .007), or experience difficulty walking as far as they wanted (63% vs. 43%; P = .001). The proportion of patients who played sports as much as the general population was numerically increased (52% vs. 37%; P = .033) at EoS versus BL. CONCLUSION: Results of the analysis suggest that over time, rFIXFc prophylaxis is associated with significant improvements in pain and physical functioning. This contributes to previous evidence of overall HRQoL improvements in patients with haemophilia B treated with rFIXFc.

Recombinant factor IX Fc prophylaxis reduces pain and increases levels of physical activity, with sustained, long-term improvements in patients with hemophilia B: post hoc analysis of phase III trials using patient-reported outcomes.

Background: Pain is a common symptom of hemophilia that may adversely affect patients' quality of life (QoL). Previous post hoc analyses of prophylaxis with recombinant factor IX Fc fusion protein (rFIXFc) have been published for adults and adolescents, demonstrating improvements in health-related QoL (HRQoL) when assessed by the haemophilia-specific QoL (HaemAQoL) questionnaire. Objective: To describe in depth the evolution of QoL, pain- and activity-related domains and questions for pediatric, adolescent, and adult patients with hemophilia B treated with rFIXFc prophylaxis. Design: A post hoc analysis of data from a series of clinical trials. Methods: This post hoc, long-term analysis assessed patient-reported outcomes (PROs) from the Kids B-LONG (NCT01440946: pediatric) and B-LONG (NCT01027364: adults and adolescents) parent studies and the B-YOND (NCT01425723: all age groups) extension study. Results: Ninety-two adult and adolescent patients that started in the B-LONG study were assessed, with a median (range) duration of follow-up of 58.9 (0.0-78.4) months. The Haem-A-QoL total score was significantly reduced from baseline by 4.45 (p ⩽ 0.01), as were the subdomains 'physical health' (9.10; p = 0.001), 'sports and leisure' (11.25; p ⩽ 0.01), 'treatment' (2.69; p = 0.05), and 'view of self' (5.81; p = 0.002). Thirty pediatric patients that started in the Kids B-LONG study were assessed, with a median (min-max) duration of follow-up of 36.7 (9.0-59.9) months. The high level of satisfaction demonstrated by the PROs at baseline was maintained. Conclusion: rFIXFc prophylaxis reduced perceived pain and increased levels of physical activity with sustained, long-term improvements in QoL in adult and adolescent patients with hemophilia B and maintained high QoL scores in pediatric patients.

Helping to reduce pain and increase physical activity in patients with hemophilia B People with hemophilia B do not produce factor IX (FIX) that works properly, so they need to be given additional FIX to help their blood clot. Recombinant factor IX Fc fusion protein (rFIXFc), is an extended half-life (meaning it remains active for longer than standard, unmodified FIX) treatment for hemophilia B. People with hemophilia B can experience episodes of bleeding, which can result in other symptoms, including pain, difficulty participating in sport, and poor mental health. This study shows that regularly taking rFIXFc over approximately 5 years to prevent or treat bleeds could also help to make these other symptoms better.