Experience with the oral iron chelator deferiprone in transfusion-dependent children

Abstract

Objective: To establish efficacy and safety of deferiprone.

Design: Prospective study.

Setting: The Lady Ridgeway Hospital for Children, Colombo.

Patients: Transfusion-dependent children in the age group 1 to 15 years.

Intervention: Patients were given 75 mg/kg/day of deferiprone orally in divided doses.

Measurements: Efficacy of deferiprone therapy was assessed by 4 to 6 monthly serum ferritin (SF) assays. Safety of therapy was assessed by 4-weekly white cell counts and serum alanine aminotransferase (ALT) levels. The Z-score was used to assess the significance of the difference between the mean initial and final SF level.

Results: 82 patients received deferiprone therapy for a mean duration of 30 +/- 14 months. Initial SF levels ranged from 1115 to 12,165 micrograms/l with a mean of 5156 +/- 2631 micrograms/l. Final SF levels ranged from 312 to 15,285 micrograms/l with a mean of 2809 +/- 2380 micrograms/l (Z score 5.99; p < 0.001). Two (2.4%) children developed agranulocytosis which reverted to normal on discontinuation of treatment. 41 (50%) developed arthropathy and in 17 this was severe enough to require discontinuation of therapy. Serum ALT levels were raised in 35 (43%) patients but reverted to pretreatment values or lower despite continuation of deferiprone therapy. There was one death in a 9-year old child who developed diabetes mellitus and heart failure despite deferiprone therapy for 3 years.

Conclusions: A final SF level < 2500 micrograms/l was achieved in 52% children. Severe arthropathy and agranulocytosis may necessitate permanent discontinuation of therapy.