Fernandes 2013.

Methods	Randomised controlled trial. Design: parallel group. Duration: 12 months. Location: single centre in Brazil.
Participants	Inclusion criteria: thalassaemia major, at least 7 years of age (in order to comply with MRI examinations), regularly transfused, iron overload with no prospect of changing chelation therapy in the coming 6 months after enrolment, had a record of good compliance with chelation therapy. Exclusion criteria: significant left ventricular dysfunction (ejection fraction < 35%), renal insufficiency, advanced atrioventricular conduction disturbances, and formal contraindications to MRI examinations. 15 participants were selected for randomisation from a pool of 60 individuals who had undergone repeated MRI examinations over the preceding 5 years. Total cohort N = 15, mean (SD) age 28.3 (4.9) years, 60% male. Intervention group n = 5, mean (SD) age 31.2 (3.9) years, 60% male. Mean (SD) baseline characteristics: haemoglobin 9.4 (0.65) g/dL; heart T2* 21.7 (7.2) m/s; MIC 1.19 (0.67) mg/g; LVEF 66.5 (9.2) %; serum ferritin 1110 (837) ng/mL; liver T2* 5.47 (2.97) m/s; LIC 6.5 (4.3) mg/g. Control group: n =10, mean (SD) age 26.8 (4.8) years, 60 % male. Mean (SD) baseline characteristics: haemoglobin 9.8 (0.29) g/dL; heart T2* 25.1 (8.8) m/s; MIC 1.07 (0.55) mg/g; LVEF 66.6 (6.7) %; serum ferritin 1602 (1084) ng/mL; liver T2* 5.38 (4.36) m/s; LIC 9.5 (7.9) mg/g.
Interventions	Intervention group: oral amlodipine 5 mg once daily in addition to standard chelation therapy. Control group: standard chelation therapy alone.
Outcomes	Primary outcome: difference in heart T2* values (m/s) between groups at 12 months. Secondary outcomes: heart T2* values (m/s) at 6 months, serum ferritin (ng/dL) at 6 and 12 months, LIC (mg of Fe/gm of dry weight of liver) at 6 and 12 months.
Notes	Baseline MIC and liver T2* values were not included in the published report. We obtained these values from individual patient data provided by the principal investigator. P values for type of chelation therapy used were not provided.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described.
Allocation concealment (selection bias)	Unclear risk	Not described.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Open‐label trial.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Readers of MRI were blinded to treatment allocation.
Incomplete outcome data (attrition bias) All outcomes	Low risk	One participant in the amlodipine group died before 12‐month follow up so data for this participant were not available for analysis at 12 months.
Selective reporting (reporting bias)	Low risk	All intended primary and secondary outcome data were reported.
Other bias	Low risk	None identified.