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

Abstract

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 x 10(9)L(-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 > or = 50 x 10(9)L(-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 > or = 50 x 10(9)L(-1). The median time to platelet response was </=2.5 days, and the median number of days in which the platelet count remained > or = 50 x 10(9)L(-1) was > or = 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.

Surveillance study on the tolerability and safety of Flebogamma®DIF (10% and 5% intravenous immunoglobulin) in adult and pediatric patients

“…This is consistent with what can be observed when comparing clinical trials with these products (Berger ; Ballow ; Julia et al. ; Berger et al. ).…”

“…Previous data from clinical trials performed with Flebogamma DIF at 10% and 5% concentrations showed a frequency of infusions with potentially related AEs, relative to the number of infusions, of 30.5% and 10.8%, respectively (Berger 2007;Ballow 2009;Julia et al 2009;Berger et al 2010). Therefore, to ensure more than 90% power using a one-sided test with a significance level of 0.01, an effective sample size of at least 102 infusions per group was needed to detect a difference of 20% in the rates of both concentrations (sample size for the comparison of two independent proportions with Z test).…”

“…In clinical trials performed with Flebogamma DIF (the evolution of Flebogamma), a difference of around 20% points between 10% and 5% products (10.8% and 30.5%, respectively) is observed in the rate of infusions with potentially related AEs in relation to the number of infusions (Berger ; Ballow ; Julia et al. ; Berger et al. ).…”

“…Results from previous studies in patients with primary immunodeficiencies (PID) and immune‐mediated idiopathic thrombocytopenic purpura (ITP) have shown that Flebogamma DIF 5% and 10% are safe and effective for the treatment of these conditions (Berger and Pinciaro ; Ballow , ; Julia et al. ; Berger et al. ).…”

“…Results from previous studies in patients with primary immunodeficiencies (PID) and immune-mediated idiopathic thrombocytopenic purpura (ITP) have shown that Flebogamma DIF 5% and 10% are safe and effective for the treatment of these conditions (Berger and Pinciaro 2004;Ballow 2009Ballow , 2013Julia et al 2009;Berger et al 2010). However, the rate of infusions associated with potentially related AEs was higher with Flebogamma DIF 10% than with the lower concentration Flebogamma DIF 5%.…”