The main purpose of this study is to evaluate the safety and efficacy of Rituximab combined with chemotherapy in CD20+ adult acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is a group of biologically heterogeneous diseases with diverse prognosis. Novel strategies for adult ALL have approached a CR rate of over 80%, which is similar to pediatric ALL. But the long term survival of adult ALL is only 30%-40%, much lower than pediatric patients.

In our trial, all the patients will first receive Vincristine 1.4mg/m2, max 2mg IV days 1,8,15,22, Daunorubicin 45mg/m2 IV days 1-3,Cyclophosphamide 750mg/m2 IV day 1 and prednisone 40-60mg/m2,by mouth days 1-14 (VDCP)regimen as initial induction therapy. If patients achieve complete remission after induction, they will be enrolled in our study for further consolidation and maintenance. If the tumor cells in bone marrow remain 5% to 20% after induction, the patients will receive VDCLP(VDCP+L-asparaginase 6000IU/m2 IV days5,7,9,11,13) and be enrolled until complete remission.

Rituximab is the main experimental intervention in our study.The consolidation regimen is HyperCVAD/MA or R-HyperCVAD/MA for totally 8 courses. The maintenance regimen includes 6-Mercaptopurine+Methotrexate for 24 months, Vincristine+Prednisone for the first 12 months, L-asparaginase in month 3 and 9 with or without Rituximab in month 6 and 12.

Inclusion Criteria:

• Diagnosis of CD20-positive ALL
• Adequate liver function (bilirubin less than or equal to 1.5*ULN, unless considered due to tumor), and renal function (creatinine less than or equal to 1.5*ULN, unless considered due to tumor)
• Signed informed consent

Exclusion Criteria:

• Prior history of treatment with high-dose Ara-C, MTX or rituximab
• Pregnant or lactating women
• History of allergy to rituximab
• Unable to sign informed consent
• Active replication of HBV
• History of stem cell transplantation