The purpose of this open-label, non-comparative, multi-center protocol was to further evaluate safety and to provide treatment with ICL670 to patients who had or were at risk of life threatening complications due to transfusional iron overload with a documented inability to tolerate any of the commercially available iron chelators due to severe toxicity rendering continued therapy either impossible or hazardous. Patients who were also ineligible for all on-going registration trials with ICL670 were included in the study. In exceptional cases, patients with a degree of iron overload which was not immediately life-threatening and who were ineligible for the registration trials were also enrolled provided they had a well-documented, sound justification for alternative chelation therapy.