Clinical pharmacology of deferasirox

Chiaki Tanaka1

  • 1Oncology Clinical Pharmacology, Novartis Pharmaceuticals Corporation, One Health Plaza, East Hanover, NJ 07936, USA, chiaki.tanaka@novartis.com.

Iron accumulation is a consequence of regular red cell transfusions, and can occur as a result of ineffective erythropoiesis secondary to increased intestinal iron absorption, in patients with various anemias. Without appropriate treatment, iron overload can lead to increased morbidity and mortality. Deferasirox is an oral iron chelator effective for reduction of body iron in iron-overloaded patients with transfusion-dependent anemias and non-transfusion-dependent thalassemia, with a well-established safety profile. This review summarizes the clinical pharmacokinetics, pharmacodynamics, and drug-drug interaction profile of deferasirox, and the claims supporting once-daily dosing for effective chelation. Sustained labile plasma iron suppression is observed with no rebound between doses, protecting organs from potential tissue damage. Increased iron excretion positively correlates with increased deferasirox exposure; to optimize iron removal transfusional iron intake, body iron burden and safety parameters should also be considered. Deferasirox dispersible tablets should be taken ≥30 min before food due to an effect of food on bioavailability. Dosing is consistent across pediatric and adult patients and there is no ethnic sensitivity. Dose adjustment is required for patients with hepatic impairment and may be considered upon coadministration with strong uridine diphosphate glucuronosyltransferase inducers or bile acid sequestrants (coadministration should be avoided where possible), and patients should be monitored upon coadministration with cytochrome P450 (CYP) 3A4/5, CYP2C8, or CYP1A2 substrates. Coadministration with hydroxyurea, a fetal hemoglobin modulator, does not appear to impact deferasirox pharmacokinetics. In summary, a substantial body of clinical and pharmacokinetic data are available for deferasirox to guide its optimal use in multiple patient populations and clinical circumstances.

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