Antileukemic effects of rapid cyclosporin withdrawal in patients with relapsed chronic myeloid leukemia after allogeneic bone marrow transplantation

The results of rapid tapering of Cyclosporin therapy in 7 patients with Philadelphia chromosome-positive chronic myeloid leukemia (CML) in relapse after allogeneic bone marrow transplantation are reported. All patients had cytogenetically-documented relapse within 6 months of transplant, and were on oral Cyclosporin therapy. Rapid tapering of Cyclosporin resulted in moderately severe acute GVHD in 2 cases, and in extensive chronic GVHD in a further 2 patients (fatal in 1 case). An antileukemic effect was observed in 6 patients, with complete haematological and cytogenetic remission observed in all cases. The seventh patient did not respond, and died after infusion of donor leucocytes. Four of the responders remain in complete remission of CML 30 to 120 months after BMT. One patient died in remission of chronic GVHD, and one patient had a complete response lasting 5 months, but relapsed and died 13 months post transplant. Rapid withdrawal of Cyclosporin therapy appears to be an effective means of treatment of early relapse of CML after transplant, and is an alternative to the use of donor leucocyte infusions for those patients still receiving Cyclosporin at the time of relapse.