Shift from intravenous or 16% subcutaneous replacement therapy to 20% subcutaneous immunoglobulin in patients with primary antibody deficiencies

In patients with primary antibody deficiencies, subcutaneous administration of IgG (SCIG) replacement is effective, safe, well-tolerated, and can be self-administered at home. A new SCIG replacement at 20% concentration (Hizentra®) has been developed and has replaced Vivaglobin® (SCIG 16%). An observational prospective multi-centric open-label study, with retrospective comparison was conducted in 15 Italian centers, in order to investigate whether and to what extent switching to Hizentra® would affect frequency of infusions, number of infusion sites, patients' satisfaction, and tolerability in patients previously treated with Vivaglobin® or intravenous immunoglobulins (IVIG). Any variations of dosage, frequency and duration of the infusions, and of number of infusion sites induced by Hizentra® with respect to the former treatment were recorded. Practical advantages and disadvantages of Hizentra®, with respect to the medicinal product formerly used, and the variations in patients' therapy-related satisfaction were monitored by means of the TSQM (Treatment Satisfaction Questionnaire for Medication); number, frequency, and duration of infectious events and adverse effects were recorded. Eighty-two patients switched to Hizentra®: 19 (23.2%) from IVIG and 63 (76.8%) from Vivaglobin®. The mean interval between infusions was not affected by the shift (7.0 ± 2.0 days with previous treatment versus 7.1 ± 1.2 during Hizentra®). A decrease in the number of infusion sites with Hizentra® was recorded in 12 out of 56 patients for whom these data were available. At 6 months, 89.7% of patients were satisfied with Hizentra®; no difference in terms of effectiveness, side effects, convenience, and global satisfaction was observed. No difference in the incidence of adverse events was reported.