Efficacy and Safety of IQYMUNE, a Ten Percent Intravenous Immunoglobulin in Adult Patients With Chronic, Primary Immune Thrombocytopenia

Abstract

Background: Intravenous immunoglobulin (IVIG) IQYMUNE is a highly purified 10% IVIG that was assessed using the new stringent definition of response described in the revised guideline on the clinical investigation of IVIG. The efficacy and the safety of IQYMUNE were investigated in adult patients with chronic primary immune thrombocytopenia (ITP).

Methods: In this phase III multinational, multicentre, prospective, uncontrolled, open-label, single-arm study, adult patients with a baseline platelet count < 30 10⁹/L were treated with IVIG 10% at a dose of 2 g/kg body weight administered over 2 consecutive days. The primary endpoint was Response over the study period and was defined according to the recent and most stringent European Medicines Agency guidelines (platelet count >= 30 /span> 10⁹/L and a>= 2-fold increase from baseline, no new bleeding, and no concomitant treatment with drugs that affect platelet count and/or induce bleeding cessation).

Results: Thirty-eight patients were enrolled; 73 infusions were administered (38 on Day 1 and 35 on Day 2). Response was reached by 24 patients corresponding to 63.2% of patients in the full analysis set (95% CI: 46.0; 78.2) and 68.6% of patients in the per-protocol set (95% CI: 50.7; 83.1). The median time to Response was 1 day. The median duration of Response was 13.5 days. Reasons for non-response were failure to reach the required platelet count (n = 12), a new bleeding event (n = 1), and forbidden medication use (n = 1). Among the 23 patients with a baseline platelet count <= 20 /span> 10⁹/L, 19 patients (82.6%) achieved a platelet count >= 50 /span> 10⁹/L at least once before Day 5 (previous European Medicines Agency definition of response). Treatment was well tolerated even in patients with a high flow rate (>= 6 mL/kg/h in 40% of patients). Headache (34.2%), pyrexia (15.8%), and creatinine renal clearance decrease, including one case of decrease in glomerular filtration rate (10.5%) were the most frequently reported drug-related adverse events.

Conclusions: Administration of IQYMUNE for 2 consecutive days at a dose of 2 g/kg was safe and efficacious. These results support the treatment of adult patients with chronic ITP with IQYMUNE.




J Hematol. 2018;7(3):87-95
doi: https://doi.org/10.14740/jh385w