A Global Cross‐Sectional Database Study of Low Dose FVIII SHL Prophylaxis in Haemophilia A

Introduction: Haemophilia treatment is costly and only 25% of patients receive adequate care. Although not optimal, Factor VIII (FVIII) low-dose prophylaxis (LDP) may reduce annual joint bleeding rates. Understanding FVIII usage, collected through the Web-Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) platform, and its association with Gross National Income per capita (GNI) and Universal Health Coverage index (UHCI) may provide insights in global disparities. Aims: To provide insights in FVIII use to advocate for LDP in low-income countries by providing: (i) statistical summary of FVIII usage, LDP prevalence, GNI and UHCI in WAPPS-Hemo in 2017-2023; (ii) estimation of the relationship between LDP probability (PLDP) and GNI/UHCI for children (≤12 years) and adults; (iii) exploratory comparison of pharmacokinetics (PKs) across LDP/non-LDP. Methods: Descriptive statistics/graphical summaries for (i) and (iii), mixed-effects logistic regression for (ii). Results: Data from 6223 severe haemophilia patients (ages 0.1-92 years) showed that 18% and 32% of countries used ≤1% LDP infusions in children and adults. LDP prevalence rose annually, peaking at 7% for children and 14% for adults. GNI was found lower in LDP-prevalent countries in children. In both children and adults, PLDP demonstrated an inverse association with GNI and UHCI. PK outcomes were similar across LDP status, except potentially for plasma-derived products in children, however limited by sample size. Conclusion: Underrepresentation of low-resource countries in WAPPS-Hemo underscores the financial challenges in haemophilia treatment. The association between GNI/UHCI and PLDP suggests cost-driven adoption of LDP in low-resource settings, especially in children. PK outcomes average similarities may facilitate LDP-usage in WAPPS-Hemo.