Clofarabine-based combination chemotherapy for relapse and refractory childhood acute lymphoblastic leukemia.

Clofarabine, one of the key treatment agents for refractory and relapsed acute lymphoblastic leukemia (ALL), achieves a remission rate of approximately 30% with single-agent clofarabine induction chemotherapy. However, a remission rate of approximately 50% was reported with a combination chemotherapy regimen consisting of clofarabine, etoposide, and cyclophosphamide. We treated two cases with refractory and relapsed ALL with combination chemotherapy including clofarabine; one was an induction failure but the other achieved remission. Both cases developed an infectious complication (NCI-CTCAE grade 3) and body pain with infusion. Prophylactic antibiotic and opioid infusions facilitated avoiding septic shock and pain. Further investigation of such cases is required.