Clinical outcome and incidence of inhibitor development in severe hemophilia patients receiving low-dose prophylaxis: a 3-year follow-up study in Senegal, West Africa

INTRODUCTION: In Africa, where access to diagnosis and treatment of hemophilia is the lowest in the world, prophylaxis is rarely used in preference to on-demand treatment. There are limited data of prophylaxis treatment from sub-Saharan Africa. The aim of this study was to evaluate clinical outcomes and inhibitor development in people with hemophilia receiving low-dose prophylaxis (LDP) in a sub-Saharan African setting. METHODS: We conducted a three-year prospective study. A once or twice weekly prophylaxis regimen of 25 IU/kg of rFVIIIFc or 30 IU/kg of rFIXFc was given to Hemophilia A and B, respectively. We evaluated clinical outcomes and inhibitors occurrence, determined by screening and titration using the Nijmegen technique. RESULTS: A total of 15 patients were included in the LDP regimen. The mean age was 6.3 years (1.5 - 10). A significant reduction was noted in the annualized bleeding rate, from 7.53 to 1.33 (p = 0.0001); the annualized joint bleeding rate passed from 3.6 to 1.4 (p = 0.001) and the proportion of severe bleeding, from 86.1% to 16.7% (p = 0.0001). The Hemophilia Joint Health Score (HJHS) moved from 9.6 to 3.4 (p = 0.0001) and the Functional Independence Score in Hemophilia (FISH) improved from 25.8 to 30.9 (p = 0.0001). School absenteeism decreased from 7.33% to 2.59%. Adherence to prophylaxis was 89.5% versus 60%. Consumption was 580 IU/kg/year versus 1254.6 IU/kg/year before and after prophylaxis, respectively. Incidence of inhibitors was 23% (3 /13 HA). CONCLUSION: The LDP in Hemophilia improves the clinical outcome without a surplus risk of inhibitor development. Using extended half-life clotting factor concentrates (CFCs) is better for prophylaxis in resource-limited countries, as they allow better compliance in treatment.