Complete molecular responses are achieved after reduced intensity stem cell transplantation and donor lymphocyte...

Patients with newly diagnosed chronic phase chronic myeloid leukemia were treated with imatinib mesylate (IM) for 6 to 12 months to establish disease control, before reduced intensity stem cell transplantation (RISCT). Escalating doses of donor lymphocyte infusions were given from 6 months after transplantation to eradicate residual disease. A total of 18 patients entered the study and 15 received RISCT (median follow-up, 31 months). RISCT was well tolerated with rapid engraftment, short inpatient stays, and few readmissions. Viral reactivation was common, although extensive graft-versus-host disease occurred infrequently. Donor lymphocyte infusions were given as part of the RISCT protocol in 13 of 15 patients. BCR-ABL transcripts continued to decrease after RISCT, and 8 (53%) patients achieved sustained undetectable levels. All patients are currently off IM. Although IM is now established as first-line therapy for chronic phase chronic myeloid leukemia, this protocol is a safe, well-tolerated, and effective strategy in these patients. This study is registered at http://www.controlled-trials.com as ISRCTN86187144.