L1 was given to eight patients with beta-thalassaemia major who had previously been treated with deferoxamine (DF) for 4-10 years. The patients' ages ranged from 11 to 27 years. Serum ferritin values ranged from 1.3 to 11.5 x 10(3) micrograms/l. L1 was given twice daily at a daily dose of 55-80 mg/kg body weight and was continued for 10 months in two patients, 9 months in three, 7 months in two patients and 4 months in one patient. As previously observed with DF, each patient's urinary iron excretion (UIE) varied greatly from day to day. The mean UIE of the eight patients ranged from 11 to 49 mg/d (0.2-0.87 mmol/d) on subcutaneous DF and from 16 to 53 mg/d (0.28-0.95 mmol/d) on L1. Two patients excreted significantly more and one patient significantly less iron while on L1. If the UIE was calculated as mmol Fe/mmol creatinine there was no statistically significant difference. Serum ferritin values fluctuated widely in all, with a consistent downward trend in three, no change in four and an increase in one of two non-splenectomized patients. This patient's splenomegaly and need for transfusions continued to increase while on L1. No toxicities attributable to the drug were detected during the period of study and tolerance of the drug was excellent.