Imatinib and methylprednisolone alternated with chemotherapy improve the outcome of elderly patients with Philadelphia-positive acute lymphoblastic leukemia: results of the GRAALL AFR09 study

Acute lymphoblastic leukemia ( ALL) in the elderly is characterized by its ominous prognosis. On the other hand, imatinib has demonstrated remarkable, although transient, activity in relapsed and refractory Philadelphia-positive acute lymphoblastic leukemia (Ph+ALL), which prompted us to assess the use of imatinib in previously untreated elderly patients. ALL patients aged 55 years or older were given steroids during 1 week. Ph+ve cases were then offered a chemotherapy-based induction followed by a consolidation phase with imatinib and steroids during 2 months. Patients in complete response (CR) after consolidation were given 10 maintenance blocks of alternating chemotherapy, including two additional 2-month blocks of imatinib. Thirty patients were included in this study and are compared with 21 historical controls. Out of 29 assessable patients, 21 (72%, confidence interval (CI): 53 - 87%) were in CR after induction chemotherapy vs 6/21 (29%, CI: 11 - 52%) in controls (P = 0.003). Five additional CRs were obtained after salvage with imatinib and four after salvage with additional chemotherapy in the control group. Overall survival ( OS) is 66% at 1 year vs 43% in the control group ( P = 0.005). The 1-year relapse-free survival is 58 vs 11% ( P = 0.0003). The use of imatinib in elderly patients with Ph+ ALL is very likely to improve outcome, including OS.