Efficacy and Safety of Deferasirox (Exjade®) during 1 Year of Treatment in Transfusion-Dependent Patients with Myelodysplastic Syndromes: Results from EPIC Trial

Abstract

Background: Many patients (pts) with myelodysplastic syndromes (MDS) [particularly those with Low- or Int-1-risk] are susceptible to iron overload from ongoing blood transfusions and increased dietary iron absorption. Deferasirox (Exjade®) has shown efficacy in maintaining or reducing body iron (assessed by liver iron concentration [LIC] and serum ferritin [SF]) in MDS pts. More recently, the efficacy and safety of deferasirox in pts with various underlying anemias, including MDS, was evaluated in the large EPIC study. Data for MDS pts are presented here.Methods: The EPIC study was a 1-yr, openlabel, single-arm, multicenter trial. Pts with transfusion-dependent MDS and SF ≥1000 ng/ mL, or SF <1000 ng/mL but requiring >20 transfusions or 100 mL/kg of blood and an R2 MRI-confirmed LIC >2 mg Fe/g dry weight (dw), received an initial deferasirox dose of 10–30 mg/kg/day. SF was assessed monthly and protocol-specified dose adjustments in steps of 5–10 mg/kg/day (range 0–40 mg/kg/day) were done every 3 mths based on SF trends and safety markers. Primary efficacy endpoint was the change in SF from baseline at 12 mths. Safety assessments included monitoring of adverse event (AE) and laboratory parameters.Results: 341 MDS pts (204 M, 137 F; mean age 67.9 yrs, range 11–89 yrs) with median baseline SF of 2730 (range 951–9465) ng/mL were enrolled. Mean transfusion duration was 3.6 yrs, and pts received a mean of 116.4 mL/kg of blood in the previous yr. Almost half (48.4%) of all pts had not received any prior chelation therapy; 40.0% had previously received deferoxamine (DFO), 4.1% deferiprone, 7.0% combination DFO/ deferiprone, and 0.3% other therapy. Overall, mean actual dose of deferasirox over 1 yr of treatment was 19.2±5.4 mg/kg/day. At 12 mths, there was a significant reduction in median SF from baseline (by LOCF: –253.0 ng/mL; P=0.0019). Median SF (range) ng/mL values at baseline, 3, 6, 9 and 12 mths were 2729.5 (951–9465; n=336), 2358.0 (534–46569; n=263), 2209.5 (357–10066; n=230), 2076.0 (358–25839; n=197) and 1903.5 (141–10155; n=174), respectively. Overall, 48.7% of pts (n=166) discontinued therapy. Reasons for withdrawal included AEs [n=78, 23% (n=44, 13% for drug-related AEs)], consent withdrawal (n=33, 10%), unsatisfactory therapeutic effect (n=6, 2%), lost to follow-up (n=2, <1%), death (n=26, 8%, none treatment-related as per investigators' assessments) and other (n=21, 6%). Most common investigator-assessed drug-related AEs were diarrhea (n=110, 32%), nausea (n=45, 13%), vomiting (n=26, 8%), abdominal pain (n=26, 8%), upper abdominal pain (n=25, 7%), rash (n=23, 7%), and constipation (n=21, 6%). Only 25 pts discontinued study drug for drug-related GI AEs. Most AEs were mild-to-moderate (95%) in severity. In total, 14.7% had two consecutive serum creatinine values >33% above baseline (in normal range), 10.6% had two values above ULN, and 24.9% had both two consecutive values >33% and >ULN; 19 pts had dose decreases and 10 dose interruptions due to abnormal creatinine; there were no progressive increases. One patient (<1%) with normal baseline alanine aminotransferase had an increase that exceeded >10xULN on two consecutive visits.Conclusions: In this large cohort of MDS pts with iron overload, deferasirox provided significant reduction in SF levels over 1-yr treatment with appropriate dose adjustments every 3 mths based on SF trends and safety markers. The AE profile in this study is consistent with previously reported deferasirox data in MDS pts. The discontinuation rate was higher in this subgroup. Investigations are ongoing to assess possible contributing factors including associated comorbidities, age of pts, and others.