HLA-Mismatched Renal Transplantation without Maintenance Immunosuppression

For the Immune Tolerance Network TO THE EDITOR: We previously reported results of our study of combined kidney and bone marrow transplantation without maintenance immunosuppression. We extended the study to include five additional patients. Here we report longer follow-up of the initial five patients and observations made after 3 years in the later cohort (Table 1). Both trials were sponsored by the Immune Tolerance Network and are currently closed to further enrollment. The first five patients received the previously described conditioning regimen (regimen 1): cyclophosphamide, thymic irradiation, anti-CD2 monoclonal antibody, and an 8-to-14-month course of a calcineurin inhibitor.1 After irreversible acute…