Health‐related quality of life and caregiver burden of emicizumab in children with haemophilia A and factor VIII inhibitors—Results from the HAVEN 2 study

INTRODUCTION: Persons with haemophilia A (PwHA) with factor (F)VIII inhibitors, including children, have impaired health‐related quality of life (HRQoL). The HAVEN 2 study (NCT027955767) of paediatric PwHA with FVIII inhibitors demonstrated that subcutaneous emicizumab prophylaxis resulted in low annualizedbleed rates. AIM: We assessed the impact of emicizumab prophylaxis on the HRQoL of children and their caregivers participating in HAVEN 2. METHODS: Children aged 8‐11 years self‐reported HRQoL using the Haemophilia‐Specific Quality of Life Assessment Instrument for Children and Adolescents Short Form (Haemo‐QoL SF II). Caregivers of children aged 0‐11 years completed the Adapted Inhibitor‐Specific Quality of Life Assessment with Aspects of Caregiver Burden. All scores were transformed to a 0‐100 scale, where lower scores reflect a better HRQoL. The number of missed days from school/day care and hospitalizations was also recorded. RESULTS: In HAVEN 2 (n = 88), the median age was 6.5 years (range: 1‐15 years); 85 participants were aged < 12 years and included in this analysis, and 34 participants were aged 8‐11 years, thereby eligible to complete the Haemo‐QoL SF II questionnaire. The mean (standard deviation, n) baseline Haemo‐QoL SF II ‘Total’ score was 30.2 (14.9, 30), indicating moderate impairment; with emicizumab, mean score decreased by −9.62 (7.73, 17) points to 23.0 (13.93, 20) by Week 49. The most improved domains were ‘Sports & School’ and ‘Physical Health’. Caregivers reported similar improvements. CONCLUSION: Prophylactic emicizumab is accompanied by substantial and sustained improvements in HRQoL of paediatric PwHA with FVIII inhibitors and their caregivers.