Serious adverse drug events during deferiprone therapy in paediatric thalassaemia Patients

Abstract

Aim/Objective: Iron-chelation therapy is essential for transfusion-dependent thalassaemia patients. Children are particularly affected by this disease and require early chelation therapy to avoid the long term effects of iron overload. Knowledge on the incidence and nature of serious adverse drug events (e.g. neutropenia, agranulocytosis) that may lead to treatment termination is of importance in this lifelong therapy. Methods: The Hong Kong Clinical Data Analysis and Reporting System (CDARS) comprising data of more than 7 million patients was used to extract all thalassaemia patients who were receiving deferiprone below the age of 18 years. Adverse drug events (ADE) were identifi ed using a selected list of ICD-9 codes and laboratory data. All identifi ed events were assessed for causality by reviewing concomitant medications, diagnoses and laboratory data. Results: 93 patients were eligible for analysis; median age was 14 years (IQR 12-16). Median duration of deferiprone therapy was 18 months (IQR 7-32). 17 patients received monotherapy and 76 combination therapy with deferoxamine. Overall incidence rates for neutropenia, agranulocytosis, elevated liver enzymes and arthropathies were 9.7%, 5.4%, 8.6% and 3.2%; in patients with monotherapy 5.9%, 0%, 17.6% and 5.9% and with combination therapy 10.5%, 7.9%, 6.6% and 2.6%, respectively. 10 patients stopped deferiprone therapy during observation; 5, 3 and 2 patients due to agranulocytosis, arthropathies and elevated liver enzymes, respectively. 48.3% of these ADEs occurred during the fi rst 3 months of therapy. Conclusion: Combination therapy seems to be more prone for serious ADEs than monotherapy. This association must be further investigated in larger cohorts and clinical settings in paediatric patients.