Clofarabine, cyclophosphamide and etoposide as single-course re-induction therapy for children with refractory/multiple relapsed acute lymphoblastic leukemia

The safety and efficacy of the combination clofarabine/cyclophosphamide/etoposide were evaluated in children with advanced acute lymphoblastic leukaemia (ALL). The study enrolled 25 paediatric patients (median age 12·5 years) with either refractory (n = 17; 68%) or multiple relapsed (n = 8; 32%) ALL to receive clofarabine 40 mg/m2, cyclophosphamide 400 mg/m2 and etoposide 150 mg/m2, daily for 5 consecutive days. No patient died from treatment-related complications. The most common adverse events were febrile neutropenia, mucositis and reversible liver toxicity; no case of liver veno-occlusive disease was reported. The overall remission rate was 56%: 13 patients (52%) achieved complete remission (CR) and one (4%) CR without platelet recovery (CRp). In seven of the 13 (54%) patients achieving CR, remissions were of sufficient duration to allow patients to receive allogeneic haematopoietic stem cell transplantation. The probability of CR/CRp was greater in the 17 patients with B cell precursor ALL than in the eight with T-ALL (76% vs. 12%, respectively, P < 0·01). The 18-month overall survival probability was 39% and 0% in patients who did or did not respond to the treatment, respectively (P < 0·01). These data suggest that the clofarabine/cyclophosphamide/etoposide regimen is well tolerated and can induce clinical response in a relevant proportion of children with refractory/multiple relapsed ALL.