The impact of previous or concomitant IFN therapy on deferiprone-induced agranulocytosis and neutropenia: a retrospective study.

Objective: Although IFN therapy is known to cause neutropenia, data on the risk of deferiprone (DFP)-induced haematological complications in patients receiving IFN are lacking.

Research Design And Methods: This was a retrospective single-centre study to assess the association between exposure to IFN for hepatitis C virus treatment and haematological side effects of DFP therapy in patients with thalassemia major and intermedia using a large database spanning 2001 – 2008. During observation time, a total of 66 patients, including 63 affected by thalassemia major and 3 by thalassemia intermedia, were treated with chelation DFP-based regimens. A subset of 25 patients was treated at least for 3 months also with IFN (6 were cotreated and 19 were pretreated).

Results: Overall, the incidence of neutropenia and agranulocytosis was 9.83 and 1.14/100 patient/year, respectively. Receipt of IFN was significantly associated with increased risk of haematological complications of DFP therapy: among patients receiving IFN, 48 and 12% experienced at least one episode of neutropenia and agranulocytosis, respectively.

Conclusions: These results suggest that IFN therapy may increase the risk of complications of DFP-based iron chelation therapy in patients with thalassemia. Further research is needed to assess whether the association observed in this retrospective single-centre observational study is due to IFN or other factors.