Clinical, humanistic, and economic burden of severe haemophilia B in adults receiving factor IX prophylaxis: findings from the CHESS II real-world burden of illness study in Europe

Background Real-world studies of the burden of severe haemophilia B in the context of recent therapeutic advances such as extended half-life (EHL) factor IX (FIX) products are limited. We analysed data from the recent CHESS II study to better understand the clinical, humanistic, and economic burden of severe haemophilia B in Europe. Data from male adults with severe haemophilia B receiving prophylaxis were analysed from the retrospective cross-sectional CHESS II study conducted in Germany, France, Italy, Spain and the United Kingdom. Inhibitors were exclusionary. Patients and physicians completed questionnaires on bleeding, joint status, quality of life, and haemophilia-related direct and indirect costs (2019–2020). All outcomes were summarised using descriptive statistics. Results A total of 75 CHESS II patients were eligible and included; 40 patients (53%) provided self-reported outcomes. Mean age was 36.2 years. Approximately half the patients were receiving EHL versus standard half-life (SHL) prophylaxis (44% vs 56%). Most patients reported mild or moderate chronic pain (76%) and had ≥ 2 bleeding events per year (70%), with a mean annualised bleed rate of 2.4. Mean annual total haemophilia-related direct medical cost per patient was €235,723, driven by FIX costs (€232,328 overall, n = 40; €186,528 for SHL, €290,620 for EHL). Mean annual indirect costs (€8,973) were driven by early retirement or work stoppage due to haemophilia. Mean quality of life (EQ-5D) score was 0.67. Conclusions These data document a substantial, persistent real-world burden of severe haemophilia B in Europe. Unmet needs persist for these patients, their caregivers, and society.

New Inhibitors in the Ageing Population: A retrospective, observational, cohort study of new inhibitors in older people with haemophilia

Introduction: A second peak of inhibitors has been reported in patients with severe haemophilia A (HA) aged >50 years in the UK.1 The reason for this suggested breakdown of tolerance in the ageing population is unclear, as is the potential impact of regular exposure to the deficient factor by prophylaxis at higher age. No data on haemophilia B (HB) has ever been reported. Aim: The ADVANCE Working Group investigated the incidence of late-onset inhibitors and the use of prophylaxis in patients with HA and HB aged ≥40 years. Methods: A retrospective, observational, cohort, survey-based study of all patients aged ≥40 years with HA or HB treated at an ADVANCE HTC. Results: Information on 3,095 people aged ≥40 years with HA or HB was collected. Of the 2,562 patients with severe HA, the majority (73% across all age groups) received prophylaxis. In patients with severe HA, the inhibitor incidence per 1,000 treatment years was 2.37 (age 40–49), 1.25 (age 50–59) and 1.45 (age 60+). Overall, the inhibitor incidence was greatest in those with moderate HA (5.77 (age 40–49), 6.59 (age 50–59) and 4.69 (age 60+) and the majority of inhibitor cases were preceded by a potential immune system challenge. No inhibitors in patients with haemophilia B were reported. Conclusion: Our data do not identify a second peak of inhibitor development in older patients with haemophilia. Prophylaxis may be beneficial in older patients with severe, and possibly moderate HA, to retain a tolerant state at higher age.

Omani experience with the use of factor IX Fc fusion protein

We describe our local experience in the management of haemophilia B patients with factor IX Fc fusion protein. Two children with haemophilia B were managed with the use of a personalised/tailored dosing schedule of factor IX Fc fusion protein. Compared with the standard half-life factor IX, prophylaxis with factor IX Fc fusion protein was cost-effective, with much less injections, better bleeding control, improved tolerability or no inhibitor development.