Emicizumab prophylaxis vs immune tolerance induction in children with severe hemophilia A and inhibitors: a retrospective comparison of bleeding control, quality of life, and cost.

BACKGROUND

There is limited evidence directly comparing emicizumab (EMI) prophylaxis and immune tolerance induction (ITI) in children with severe hemophilia A and high-titer inhibitors (SHAcwHTI), particularly bleeding control, quality of life (QoL), and cost.

OBJECTIVES

This study compared outcomes of EMI vs ITI in SHAcwHTI, focusing on bleeding rates, QoL, and costs.

METHODS

This single-center retrospective study enrolled SHA children (inhibitor titer ≥5 Bethesda Units/mL), receiving EMI or ITI from January 2020 to December 2024. EMI included loading (initial 4 weeks) and maintenance doses; ITI involved intermediate-dose (factor [F]VIII 100 IU/kg/d) or low-dose (FVIII 50 IU/kg once every other day). Outcomes included annualized bleeding rate (ABR), annualized joint bleeding rate (AJBR), Canadian Hemophilia Outcomes-Kids Life Assessment Tool scores, and medication costs.

RESULTS

Among 140 patients (24 in EMI group and 116 in ITI group [40 intermediate-dose ITI and 76 low-dose ITI]), EMI was associated with better bleeding control: median ABR and AJBR were 0 across all observation periods, significantly lower than ITI. For ITI, both ABR and AJBR declined over time but remained higher than those of EMI group. Target joint proportion decreased most markedly in patients receiving EMI (35.7%-0%; P = 0.002). EMI group also showed greater QoL improvement (mean change in parent proxy-reported Canadian Hemophilia Outcomes-Kids Life Assessment Tool scores: +26.6 vs +19.2 vs +19.1; P < .001) and lower medication costs (1993.4 vs 3703.4 vs 3656.3 US$/kg; P < .001).

CONCLUSIONS

EMI prophylaxis was associated with improved bleeding control and QoL while reduced costs compared with ITI, offering a valuable option for SHAcwHTI, prioritizing immediate hemostasis over the long-term goal of inhibitor eradication, especially in resource-limited settings.