Safety, Tolerability, and Efficacy Of Hizentra® In Japanese Patients With Primary Immunodeficiency Over 48 Weeks

Abstract

Hizentra® immunoglobulin for subcutaneous use has been shown to be well tolerated and efficacious in adult and pediatric Japanese patients with primary immunodeficiency (PID) over 24 weeks. This report combines results from Japanese Phase III and Phase III follow-up studies to evaluate the safety and efficacy of Hizentra® over 48 weeks. Twenty-five Japanese patients with PID participated in the Phase III study, with 23 thereof enrolling in a 24-week prospective, multicenter, open-label, single-arm Phase III follow-up study. Patients received weekly Hizentra® infusions for up to 48 weeks. Safety endpoints were the rate, severity, and relatedness of adverse events (AEs) per infusion. Efficacy evaluations included serum IgG trough levels and serious bacterial infections (SBIs). All patients (25) experienced at least one AE (452 AEs reported, 0.406 AE/infusion). Two serious AEs were reported: encephalitis (severe) and bacterial infection (moderate); both were considered unrelated to Hizentra®. All other AEs were mild or moderate in intensity. The highest incidence of patients with AEs, excluding infection, involved local reactions (21 patients, 84%), the frequency of which decreased substantially over the course of the studies. The mean Hizentra® dose/week was 92.8 mg/kg (range: 26.7–177.8) in the follow-up study. Treatment with Hizentra® maintained high and stable serum IgG levels (mean 7.47–8.05 g/L) and effective passive immunity to control infections (no SBIs reported). Hizentra® was well tolerated and efficacious in Japanese patients with PID treated over 48 weeks. These Japanese studies confirm the safety and efficacy profile of Hizentra® observed in studies conducted in Europe and the US.