Response of iron overload to deferasirox in rare transfusion-dependent anaemias: Equivalent effects on serum ferritin and labile plasma iron for haemolytic or production anaemias

It is widely assumed that, at matched transfusional iron-loading rates, responses to chelation therapy are similar, irrespective of the underlying condition. However, data are limited for rare transfusion-dependent anaemias, and it remains to be elucidated if response differs, depending on whether the anaemia has a primary haemolytic or production mechanism. Methods: The efficacy and safety of deferasirox (Exjade ®) in rare transfusion-dependent anaemias were evaluated over 1yr, with change in serum ferritin as the primary efficacy endpoint. Initial deferasirox doses were 10-30mg/kg/d, depending on transfusion requirements; 34 patients had production anaemias, and 23 had haemolytic anaemias. Results: Patients with production anaemias or haemolytic anaemias had comparable transfusional iron-loading rates (0.31 vs. 0.30mLred blood cells/kg/d), mean deferasirox dosing (19.3 vs. 19.0mg/kg/d) and baseline median serum ferritin (2926 vs. 2682ng/mL). Baseline labile plasma iron (LPI) levels correlated significantly with the transfusional iron-loading rates and with serum ferritin levels in both cohorts. Reductions in median serum ferritin levels were initially faster in the production than the haemolytic anaemias, but at 1yr, similar significant reductions of 940 and 617ng/mL were attained, respectively (-26.0% overall). Mean LPI decreased significantly in patients with production (P<0.0001) and haemolytic (P=0.037) anaemias after the first dose and was maintained at normal mean levels (<0.4μm) subsequently. The most common drug-related, investigator-assessed adverse events were diarrhoea (n=16) and nausea (n=12). Conclusions: At matched transfusional iron-loading rates, the responses of rare transfusion-dependent anaemias to deferasirox are similar at 1yr, irrespective of the underlying pathogenic mechanism. © 2011 John Wiley & Sons A/S.