Summary
This is a nonrandomized study of ruxolitinib in combination with a standard multi-agent
chemotherapy regimen for the treatment of B-cell acute lymphoblastic leukemia. Part 1 of
the study will optimize the dose of study drug (ruxolitinib) in combination with the
chemotherapy regimen. Part 2 will evaluate the efficacy of combination chemotherapy and
ruxolitinib at the recommended dose determined in Part 1.