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.