Efficacy of low dose clofarabine in refractory precursor T- acute lymphoblastic leukemia.

Refractory T-lymphoblastic leukemia in adults has a poor prognosis in patients who relapse after allogeneic stem cell transplantation, and relatively few new agents have demonstrated activity. Clofarabine is a novel nucleoside analog that has been associated with significant clinical activity in relapsed pediatric B-ALL. We used low dose clofarabine and induced a remission in a patient who relapsed in the skin and marrow after allogeneic transplant and was refractory to nelarabine and report a near complete response, suggesting significant activity for low intermittent dose clofarabine in patients with relapsed T-cell leukemias.