Real-world evidence from Japan in patients with hematological malignancies and secondary hypogammaglobulinemia treated with 20% subcutaneous immunoglobulin, Ig20Gly: A retrospective cohort study

Secondary immunodeficiency (SID) and hypogammaglobulinemia have been reported to be related to an increase in various infections and poor outcome, and it is important to evaluate immunoglobulin replacement therapy (IgRT) at an appropriate timing. The objective of this study is to evaluate the safety and efficacy of glycine-stabilized 20% subcutaneous immunoglobulin (Ig20Gly) in Japanese patients with hematological malignancies accompanied by SID. The patients who were administered Ig20Gly at least once at Tottori Prefectural Central Hospital were enrolled in this study. Information about the patient characteristics, hematological parameters, presence or absence of histories of infection before and after IgRT, and all adverse events during and after Ig20Gly administration was collected from clinical records. We retrospectively evaluated the efficacy and safety of Ig20Gly in 27 patients with a median age of 68 years. The incidences of infection during the 1 year prior to the initiation of IgRT, the period of l-proline-stabilized 20% subcutaneous immunoglobulin administration, and the period of Ig20Gly administration were 3.67/patient-years, 1.81/patient-years, and 1.32/patient-years, respectively. No systemic adverse events were observed during the period of Ig20Gly administration, but a total of 69 cases of local adverse events were observed in 18 patients (66.7%). All adverse events were grade 1 and mild. Ig20Gly reduced the incidence of infection in patients with SID, and few systemic and only mild local adverse events were observed, suggesting a high level of safety.