Deferasirox effect on renal haemodynamic parameters in patients with transfusion-dependent β thalassaemia

Some patients with β thalassaemia experience non-progressive creatinine increases with deferasirox, mostly within normal limits; the mechanisms involved are not fully elucidated. The effects of deferasirox on renal haemodynamics, including glomerular filtration rate (GFR) and renal plasma flow (RPF), were investigated in a Phase I, open-label study in β thalassaemia major patients with iron overload. Patients received deferasirox 30 mg/kg/d up to Week 8, followed by a 2-week washout period, and extended treatment up to Week 104 with a 4-week washout period. In the short-term study (n = 11), mean GFR and RPF declined from baseline to Week 8 (mean [%] change:-9·2 [-9·5%] and -105·7 ml/min [-17·8%], respectively). A similar pattern was observed during the long-term study (n = 5); mean GFR and RPF decreased up to Week 52 (-19·1 [-17·7%] and -155·6 ml/min [-26·1%]), with similar change at Week 104 (-18·4 [-17·2%] and -115·9 ml/min [-19·6%]). Measures returned to baseline values after each washout. Serum creatinine and creatinine clearance followed a similar pattern. Effects of deferasirox on renal haemodynamics were mild and reversible for up to 2 years of treatment, with no progressive worsening of renal function over time. www.clinicaltrials.gov: NCT00560820.