Immunoglobulin G (IgG) replacement therapy is the standard of care for patients with primary immunodeficiency (PID). Intravenous (IVIG) requires less frequent infusions and is beneficial for highly symptomatic patients, due to an immediate rise in serum IgG concentration post-infusion. IVIG is favorable for elderly and patients with aversion to self-administration. This study assessed the safety of Privigen® (IgPro10, CSL Behring, King of Prussia, PA, USA) in Japanese PID patients.
This was a prospective, Phase 3, open-label, single-arm study. Privigen® was administered at pre-study doses of 138–556 mg/kg body weight per dosing cycle (3- or 4-weekly) for up to 4 months including a 12-week wash-in/wash-out period. Frequency and intensity of adverse events (AEs), relationship to study drug and AE rate per infusion (AERI) were assessed.
Ten patients completed the study. The median (range) total duration of exposure was 16.14 (4.1–16.3) weeks. A total of 19 AEs, most of which mild (45.5%), were reported in 8 patients, giving an AERI of 0.442. One AE was deemed related to Privigen® treatment (infusion site discomfort, resolved). Three patients experienced temporally associated AEs (within 72 h post-infusion). No serious AEs or deaths were reported. Most patients (90%) tolerated flow rates of ≥8 mg/kg/min, of which 5 (50%) tolerated 12 mg/kg/min. This translated into a 3-fold decrease in mean (SD) infusion time, from 173.4 (53.65) min for the first to 58.5 (14.24) min during the fourth infusion.
Privigen® was well tolerated at flow rates of up to 12 mg/kg/min.