Clinical efficacy and safety of Flebogammadif®, a new high‐purity human intravenous immunoglobulin, in adult patients with chronic idiopathic thrombocytopenic purpura

summary. Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by a low platelet count and bleeding, whose incidence is approximately 6·2 for each 100 000 adults per year. Intravenous immunoglobulins (IVIG) can be useful in patients with ITP to prevent bleeding or prior to surgery. In this study, the efficacy and safety of Flebogammadif®, a new high-purity IVIG, were assessed by an open, multicentre, non-controlled, prospective study in adult patients with chronic ITP. A total of 20 patients (enrolled if experiencing chronic ITP since at least 6 months before recruitment and if platelet count <20 ×109L−1 before treatment) received 0·4 g kg−1-bw of Flebogammadif® for 5 consecutive days and were followed-up for 3 months. Efficacy endpoints were three: proportion of patients who reached a platelet count ≥50 ×109L−1, time for the platelet count to reach that level and duration of response. Safety parameters [adverse events (AE), laboratory determinations and vital signs] and viral markers were regularly monitored. A total of 14 patients achieved a platelet count of ≥50 ×109L−1. The median time to platelet response was ≤2·5 days, and the median number of days in which the platelet count remained ≥50 ×109L−1 was ≥7 days. A regression of haemorrhages was reported for 17 patients on day 14. Eight patients presented 21 AEs (mostly mild) potentially related to the study drug. Neither abnormalities in laboratory values nor in viral markers were registered during the follow-up period. Flebogammadif® was well tolerated and succeeded in providing a haemostatic platelet count in patients with ITP.