Benefits of immunoglobulin substitution in primary and secondary immunodeficiencies: Interim analysis of a prospective, long-term non-interventional study

Objective: To assess the safety, tolerability, and effectiveness of the intravenous immunoglobulin (IVIG) Intratect 100 g/L in a prospective, large-scale non-interventional study (NIS) of patients with a wide range of antibody deficiencies as well as other indications for IVIG, risk factors, and frequency of pre-treatments. Materials and methods: Patients were enrolled at 53 practices and clinics in Germany. After recording of baseline information, each patient was treated according to need, as judged by the physician and guided by the SmPC. Relevant data were acquired from medical records, and the patients completed questionnaires to assess treatment satisfaction and quality of life (QoL). Results: At cut-off for this interim analysis, 488 patients were enrolled (planned: 1,000). 47% were male, age 16 – 91 (median 61) years, with treatment durations up to 2,225 (median 282) days. Indications were primary (32%) and secondary (61%) immunodeficiencies, immune thrombocytopenia (4%), and others (3%). More than 92% of physicians recorded very good effectiveness and satisfaction. Patient satisfaction and QoL increased with time from baseline. Initially, 31% of the SID patients had inadequate IgG trough levels (< 4 g/L), including patients with (37%) and without (63%) previous IVIG treatment. Despite a relatively low IVIG dose (median 0.2 g/kg), trough levels improved: after 3 infusions, only 22% of patients had trough levels < 4 g/L, with a plateau below 17% after 6 infusions. Adverse reactions were observed at a rate of 3% per infusion, whereas 0.08% accounted for serious reactions. Conclusion: Effectiveness, safety, patient satisfaction, and QoL were good, confirming the positive benefit-risk profile of the IVIG.