Allogeneic Stem Cell Transplants the Choice for Gleevec Resistant CML and ALL Patients
Researchers from M.D. Anderson Cancer Center have reported that 6 of 10 patients with chronic myeloid leukemia (CML) or acute lymphoblastic leukemia (ALL) who were resistant to Gleevec (imatinib) were in complete molecular remission after an allogeneic stem cell transplant. The details of this study appeared in the August 15, 2006 issue of Blood.
Some patients with CML and ALL become resistant to Gleevec, and resistance is usually associated with Bcr-Abl mutations. Several drugs have been developed which are effective for patients with Bcr-Able mutations. At the present time the only potentially curative approach to the treatment of Gleevec-resistant patients with CML and ALL is an allogeneic stem cell transplant. However, there is very little published data on the effectiveness of salvage transplants in Gleevec-resistant patients.
The current study evaluated the effectiveness of allogeneic stem cell transplantation in 9 patients with CML and one with Philadelphia chromosome positive ALL. Three of the CML patients were in chronic phase, 4 in accelerated phase and 2 in blastic phase. A myeloablative regimen of busulfan and cytoxan were used in 7 patients and 3 received reduced intensity fludarabine based regimens. Half the patients received stem cells from a related and half from an unrelated stem cell donor.
