To characterize the PK of deferasirox in pediatric β-thalassemia major patients aged from 2 to less than 6 years old, when administrated with a fixed starting dose of 20 mg/kg/day.

Inclusion Criteria:

• Pediatric patients aged from 2 to less than 6 years old.
• Patients with transfusion dependent β-thalassemia major.
• Serum ferritin values ≥ 1000 ng/ml at screening.
• Written informed consent must be obtained from the patient's legal guardian in accordance with local law and regulation prior to any screening procedures.

Exclusion Criteria:

• Non-transfusion-dependent thalassemia.
• Systemic diseases which would prevent study treatment (e.g. uncontrolled hypertension, cardiovascular, renal, hepatic, metabolic, etc.)
• Serum creatinine > age adjusted ULN.
• Significant proteinuria as indicated by a urinary protein/creatinine ratio (UPCR) ≥ 0.5mg/mg in a non-first void urine sample at screening. If UPCR is found to be ≥ 0.5 mg/mg the test can be repeated after 1 month.
• ALT/AST > 2.5xULN and total bilirubin > 1×ULN.
• Left ventricular ejection fraction < 56% by echocardiography.
• Patient has a known history of HIV seropositivity or history of active/treated hepatitis B or C (a test for screening is not required).
• A history of clinically relevant ocular and/or auditory toxicity related to iron chelation therapy
• Any surgical or medical conditions which will significantly alter the absorption, distribution, metabolism or excretion of the drug(e.g. ulcerative disease, uncontrolled nausea, vomiting, malabsorption syndrome, obstruction, or stomach and/or small bowel resection).
• Other conditions which investigator deems potential harm to patients if participate the study.