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Aims: Iron overload adversely affects patients with myelodysplastic syndromes (MDS), but benefits of iron chelation therapy have not been clearly demonstrated. We examined the association between deferasirox (DFX) therapy and mortality in transfusion-receiving Medicare patients., Patients & Methods: MDS patients from 2005 to 2008 were identified using ICD-9 codes from 100% Medicare claims. Patients receiving ≥20 blood units were observed until death or end of study. Marginal structural models were used for estimation., Results: 3926 patients (10.1% used DFX) were observed for a mean of 48.8 weeks. Each incremental week of DFX was associated with a significant reduction in mortality risk (hazard ratio [HR]: 0.989; 95% CI: 0.983-0.996; p = 0.001)., Conclusion: DFX therapy is associated with a reduced mortality risk among older MDS patients who received a minimum transfusion threshold.

Background: Deferasirox is a once-daily, oral iron chelator that was developed out of a need for a long-acting, conveniently-administered chelator for patients with transfusional hemosiderosis. The approved mode of administration requires taking deferasirox on an empty stomach with water, apple juice, or orange juice to limit variation in bioavailability. This required administration schedule might not be palatable for patients. Additionally, approximately one-quarter of patients experience mild to moderate gastrointestinal (GI) symptoms, which may pose additional challenges, particularly in the younger and older age ranges. We present a trial to assess the palatability and safety of various administration modes of deferasirox in pediatric and adult patients., Procedures: Participants rated palatability in a 4-week run-in phase, where deferasirox was administered per label. Subsequently, patients rated several administration modes during a 3-month assessment phase., Results: Palatability was more favorable during the assessment phase, with 47% of patient ratings for palatability being favorable while only 38% were favorable during the run-in phase. The most highly rated choice was deferasirox taken with a soft food at breakfast. In addition, there was an indication of improved GI tolerability during the assessment phase (symptoms were reported in 37% of patients during run-in and 32% during the assessment phase; rates of diarrhea decreased significantly). Although trough PK values increased, no major new toxicities were observed., Conclusions: These data indicate that different administration options may improve palatability and GI tolerability, which could have a positive impact on treatment adherence. (ClinicalTrials.gov number, NCT00845871), (Copyright © 2013 Wiley Periodicals, Inc.)

Purpose: This 3-year, prospective, multicenter trial assessed the safety and efficacy of deferasirox in low- or intermediate-1-risk myelodysplastic syndrome (MDS)., Patients and Methods: Eligible patients had serum ferritin ≥ 1,000 μg/L and had received ≥ 20 units of RBCs with ongoing transfusion requirements. The starting dose of deferasirox was 20 mg/kg/d, with dose escalation up to 40 mg/kg/d permitted., Results: A total of 176 patients were enrolled, and 173 patients received therapy. Median serum ferritin decreased 23% in the 53% of patients who completed 12 months of treatment (n = 91), 36.7% in patients who completed 2 years (n = 49), and 36.5% in patients who completed 3 years (n = 33) despite continued transfusion requirement. Reduction in serum ferritin significantly correlated with ALT improvement (P < .001). Labile plasma iron (LPI) was measured quarterly during the first year of the study. Sixty-eight patients (39.3%) had elevated LPI at baseline. By week 13, LPI levels normalized in all patients with abnormal baseline level. Fifty-one (28%) of 173 patients experienced hematologic improvement by International Working Group 2006 criteria; of these, only seven patients received growth factors or MDS therapy. Over the 3-year study, 138 (79.8%) of 173 patients discontinued therapy, 43 patients (24.8%) because of adverse events or disease progression and 23 patients (13.2%) because of abnormal laboratory values. The most common drug-related adverse events were gastrointestinal disturbances and increased serum creatinine. There were 28 deaths, none of which were considered related to deferasirox., Conclusion: Deferasirox reduces serum ferritin and LPI in transfusion-dependent patients with MDS. A subset of patients had an improvement in hematologic and hepatic parameters.

The US04 trial was a multicenter, open-label, single arm trial of deferasirox monotherapy (30-40 mg/kg/day) for 18 months. Cardiac iron response was bimodal with improvements observed in patients with mild to moderate initial somatic iron stores; relationship of cardiac response to labile plasma iron is now presented. Labile plasma iron was measured at baseline, six months, and 12 months. In patients having a favorable cardiac response at 18 months, initial labile plasma iron was elevated in only 31% of patients at baseline and no patient at six or 12 months. Cardiac non-responders had elevated labile plasma iron in 50% of patients at baseline, 50% patients at six months, and 38% of patients at 12 months. Risk of abnormal labile plasma iron and cardiac response increased with initial liver iron concentration. Persistently increased labile plasma iron predicts cardiac non-response to deferasirox but labile plasma iron suppression does not guarantee favorable cardiac outcome. Study registered at www.clinicaltrials.gov (NCT00447694).

We report the first prospective study evaluating the effects of deferasirox on liver iron concentration (LIC), labile plasma iron (LPI) and pharmacokinetics (PK) along with serum ferritin values in patients with IPSS Low- and Intermediate-1 risk myelodysplastic syndromes (MDS) and evidence of iron overload. Twenty-four heavily transfused MDS patients were enrolled in a planned 52 weeks of therapy. PK studies showed dose-proportional total drug exposure. Data demonstrated that deferasirox was well tolerated and effectively reduced LIC, LPI and serum ferritin in the iron-overloaded patients with MDS who completed 24 and 52 weeks of therapy despite ongoing receipt of red blood cell transfusions., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

We present results from a prospective, multicenter, open-label, single-arm study evaluating response of cardiac and liver iron to deferasirox therapy for 18 months. Twenty-eight patients with abnormal T2* and normal left ventricular ejection fraction were enrolled from 4 US centers. All patients initially received deferasirox doses of 30 to 40 mg/kg per day. Patients were severely iron overloaded: mean liver iron concentration (LIC) 20.3 mg Fe/g dry weight, serum ferritin 4417 ng/mL, and cardiac T2* 8.6 ms. In the intent-to-treat population, 48% reached the primary endpoint (cardiac T2* improvement at 18 months, P = not significant). There were 2 deaths: 1 from congestive heart failure and 1 from sepsis. In the 22 patients completing the trial, LIC and cardiac T2* improvements were 16% (P = .06) and 14% (P = .07), respectively. Cardiac T2* improvement (13 patients) was predicted by initial LIC, final LIC, and percentage LIC change, but not initial cardiac T2*. Cardiac iron improved 24% in patients having LIC in the lower 2 quartiles and worsened 8.7% in patients having LIC in the upper 2 quartiles. Left ventricular ejection fraction was unchanged at all time points. Monotherapy with deferasirox was effective in patients with mild to moderate iron stores but failed to remove cardiac iron in patients with severe hepatic iron burdens. This study was registered at www.clinicaltrials.gov as #NCT00447694.

Tens of thousands of transfusion-dependent (eg, thalassemia) patients worldwide suffer from chronic iron overload and its potentially fatal complications. The oral iron chelator deferasirox has become commercially available in many countries since 2006. Although this alternative to parenteral deferoxamine has been a major advance for patients with transfusional hemosiderosis, a proportion of patients have suboptimal response to the maximum approved doses (30 mg/kg per day), and do not achieve negative iron balance. We performed a prospective study of oral deferasirox pharmacokinetics (PK), comparing 10 transfused patients with inadequate deferasirox response (rising ferritin trend or rising liver iron on deferasirox doses > 30 mg/kg per day) with control transfusion-dependent patients (n = 5) with adequate response. Subjects were admitted for 4 assessments: deferoxamine infusion and urinary iron measurement to assess readily chelatable iron; quantitative hepatobiliary scintigraphy to assess hepatic uptake and excretion of chelate; a 24-hour deferasirox PK study following a single 35-mg/kg dose of oral deferasirox; and pharmacogenomic analysis. Patients with inadequate response to deferasirox had significantly lower systemic drug exposure compared with control patients (P < .00001). Cmax, volume of distribution/bioavailability (Vd/F), and elimination half-life (t(1/2)) were not different between the groups, suggesting bioavailability as the likely discriminant. Effective dosing regimens for inadequately responding patients to deferasirox must be determined. This trial has been registered at http://www.clinicaltrials.gov under identifier NCT00749515.

Background: Adherence to long-term treatment is challenging. Deferasirox (DFX) is a daily oral iron chelator approved in the United States for transfusional iron overload., Procedures: Twenty-one subjects with sickle cell disease (mean age 13.8+/-4.2 y) received DFX 20 to 30 mg/kg daily for 1-year while on chronic blood transfusions. Good adherence to DFX was defined as > or =80% intake of prescribed dose. Adherence was assessed by monthly pill counts and calendars, and questionnaires at 1, 3, 6, and 12 months follow-up., Results: Fifteen of 21 subjects (71%) were adherent to DFX according to self-reports, with 83% of the patients being adherent at 1 month, 89% at 3 months, 65% at 6 months, and 78% at 12 months. We were only able to document continuous good adherence in 43% of patients by pill counts because of poor bottle return. The discrepancy between pill counts and self-reports may be related to over-reporting, with the real adherence being lower. Parental involvement with DFX administration (P=0.03) and age < or =16 years (P=0.0055) correlated with adherence. We could not detect a significant correlation between serum ferritin declines and adherence., Conclusion: Seventy-one percent of patients adhered to DFX according to questionnaire responses but only 43% did according to pill counts. Adherence was poorer in adolescents older than 16 years of age and in patients who had no parental supervision of medications.