The role of allogeneic stem cell transplantation in chronic myeloid leukemia is being reevaluated. Whereas drug treatment has been shown to be superior in first line treatment, data on allo SCT as second line therapy after imatinib failure are scarce. Using an interim safety analysis of the German randomized CML-Study IV designed to optimize imatinib therapy by combination, dose-escalation and transplantation we here report on 84 patients consecutively transplanted according to predefined criteria (low EBMT score, imatinib failure, and advanced disease). Three year survival after transplantation of 56 patients in chronic phase was 91% (median follow-up 30 months). Transplantation related mortality was 8%. In a matched pair comparison of transplanted and non-transplanted patients, survival was not different. Three year survival after transplantation of 28 patients in advanced phase was 59%. 88% of transplanted patients achieved complete molecular remissions. We conclude that allo SCT could become the preferred second line option after imatinib failure for suitable patients with a donor. The study is registered at the National Institute of Health, ClinicalTrials.gov: NCT00055874.
