RESUMO
OBJECTIVES: To assess the effect of iron chelation therapy with deferasirox on cardiac iron and function in patients with transfusion-dependent thalassemia major, sickle cell disease (SCD), and myelodysplastic syndromes (MDS). METHODS: This phase IV, single-arm, open-label study over 53 wk evaluated the change in cardiac and liver iron load with deferasirox (up to 40 mg/kg/d), measured by magnetic resonance imaging (MRI). RESULTS: Cardiac iron load (myocardial T2*) significantly improved (P = 0.002) overall (n = 46; n = 36 thalassemia major, n = 4 SCD, n = 6 MDS). Results were significant for patients with normal and moderate baseline cardiac iron (P = 0.017 and P = 0.015, respectively), but not in the five patients with severe cardiac iron load. Liver iron concentration (LIC) significantly decreased overall [mean LIC 10.4 to 8.2 mg Fe/g dry tissue (dw); P = 0.024], particularly in those with baseline LIC >7 mg Fe/g dw (19.9 to 15.6 mg Fe/g dw; P = 0.002). Furthermore, myocardial T2* significantly increased in patients with LIC <7 mg Fe/g dw, but not in those with a higher LIC. Safety was consistent with previous reports. CONCLUSIONS: Once-daily deferasirox over 1 yr significantly increased myocardial T2* and reduced LIC. This confirms that single-agent deferasirox is effective in the management of cardiac iron, especially for patients with myocardial T2* >10 ms (Clinicaltrials.gov identifier: NCT00673608).
Assuntos
Benzoatos/uso terapêutico , Transfusão de Sangue , Terapia por Quelação , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Ferro/metabolismo , Miocárdio/metabolismo , Triazóis/uso terapêutico , Adolescente , Adulto , Idoso , Benzoatos/farmacologia , Deferasirox , Feminino , Ferritinas/sangue , Testes de Função Cardíaca , Hemoglobinopatias/complicações , Hemoglobinopatias/terapia , Humanos , Quelantes de Ferro/farmacologia , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reação Transfusional , Resultado do Tratamento , Triazóis/farmacologia , Adulto JovemRESUMO
BACKGROUND: There is still a clinical need for a well-tolerated and safe iron chelator for the treatment of transfusional iron overload. We describe the pharmacokinetic properties and safety data after 7 days of dosing of FBS0701, a novel oral, once-daily iron chelator. DESIGN AND METHODS: This phase 1b dose-escalation study to assess the safety, tolerability, pharmacokinetics and pharmacodynamics of FBS0701, a novel oral iron chelator for the treatment of transfusional iron overload, was conducted in 16 adult patients with iron overloaded consequent to transfusions. FBS0701 was given daily for 7 days at doses up to 32 mg/kg and was well tolerated at all dose levels. RESULTS: Pharmacokinetics showed dose-proportionality. The maxium plasma concentration (C(max)) was reached within 60-90 minutes of dosing and the drug was rapidly distributed at the predicted therapeutic doses. The plasma elimination half-life (t(1/2)) was approximately 19 hours. There were no serious adverse events associated with the drug. Conclusions On the basis of these safety and pharmacokinetic data, FBS0701 warrants further clinical evaluation in patients with transfusional iron overload. (Clinicaltrials.gov identifier: NCT01186419).
Assuntos
Etil-Éteres/farmacocinética , Etil-Éteres/uso terapêutico , Quelantes de Ferro/farmacocinética , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Tiazóis/farmacocinética , Tiazóis/uso terapêutico , Reação Transfusional , Administração Oral , Adulto , Etil-Éteres/efeitos adversos , Feminino , Humanos , Quelantes de Ferro/efeitos adversos , Masculino , Tiazóis/efeitos adversos , Adulto JovemRESUMO
Acquired hemophilia A (AH) is a rare and serious acquired bleeding disorder where prompt and correct diagnosis is crucial, and immune suppression is often required for factor VIII (FVIII) autoantibody eradication. The acquired FVIII deficiency usually manifests as bruises and bleeding, and treatment such as FVIII has limited efficacy because of the neutralizing FVIII inhibitor. Expensive bypassing agents such as recombinant activated factor VII (rFVIIa) may be required to treat clinically significant bleeding. This report summarizes the experience related to AH from a large Australian hemophilia center based in South Australia. We identified 25 patients retrospectively over 12 years (1997 to 2008) and reviewed diagnostic features, treatment for bleeds and to eradicate the autoantibody, treatment response, and survival outcomes. The incidence in South Australia was 1.20 cases per million/year with a median age of 78 years with an approximately equivalent sex ratio (12 males versus 13 females); median FVIII and inhibitor titer were 2.5 IU/dL and 11.0 BU/mL, respectively. Twenty-four patients were evaluated further. Thirteen patients (54%) required hemostatic agents, and rFVIIa was used in seven for major bleeds, of which four were limb or life threatening. Eighteen patients were treated by hematologists with immune suppression, and combination steroid and azathioprine was used most commonly to eradicate autoantibody; 15 of these 18 achieved remission (i.e., 83% response rate). Two patients had persistent low-titer inhibitor when treatments were withdrawn, and one died of a fatal bleed shortly after starting treatment. One had spontaneous remission. Five patients (33%) relapsed, three in less than 6 months after starting treatment; all were retreated successfully. Rituximab was used in six patients for high-titer inhibitor, second relapse, two life-threatening bleeds, underlying lymphoma, and steroid intolerance, respectively. Overall mortality was 25% ( N = 6), five of whom were not treated. Advanced age and lack of treatment were predictive of poor survival outcomes. The very elderly (>75 years of age) may warrant a different treatment modality such as rituximab, which is potentially more tolerable and efficacious.