Inclusion Criteria:
* Age ≥ 18 years of age.
* Newly diagnosed CD19+ and CD22+ B-ALL.
* Patients ≥55 years old, OR
* Patients 18-54 years old who decline or are deemed unfit for conventional chemotherapy with at least one of the following critieria:
* ECOG performance status of 2 or more
* Severe cardiac comorbidity (including congestive heart failure requiring treatment, ejection fraction ≤50% but greater than 40%)
* Known pulmonary comorbidity (including DLCO ≤65% or FEV1 ≤65%)
* Renal comorbidity (including creatinine clearance 30-70 mL/min)
* Any other comorbidity that the physician judges to be incompatiable with chemotherapy
* Patients with isolated extramedullary disease will be allowed as long as they have identifiable disease by PET CT at time of enrollment.
* Philadelphia chromosome negative by FISH/karyotype for t(19;22) or RT PCR for bcr-abl transcript.
* CD19 and CD22 expression will be confirmed by enrolling institutions prior to study registration by flow cytometry and/or IHC.
* Creatinine ≤2.0 mg/100 ml or creatinine clearance ≥30 mL/min
* Direct bilirubin ≤2.0 mg/100 ml, AST and ALT ≤3.0x upper limit of normal (ULN)
Exclusion Criteria:
* Patients with Burkitt's lymphoma, T-ALL, CML in lymphoid blast crisis and mixed phenotype acute leukemia (MPAL).
* Patients with B-ALL who received prior treatments, with the exception of corticosteroid, hydroxyurea, or one dose of vincristine, are ineligible.
* Patients with Ph+ B-ALL by FISH or RT PCR.
* ECOG performance status \>2.
* Left ventricular ejection fraction (LVEF) \<40%.
* History of sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease (VOD).
* Ongoing need for systemic T-cell suppressive therapy (e.g. corticosteroids, tacrolimus, cyclosporine, etc.) for active autoimmune disease or prior solid organ transplantation.
* Pregnant or lactating women. Women and men of childbearing age should use effective contraception while on this study and continue for 1 year after all treatment is finished.
* Patients with HIV or active hepatitis B or hepatitis C infection are ineligible.
* Patients with concurrent active malignancies as defined by malignancies requiring any therapy other than expectant observation or hormonal therapy, with the exception of squamous and basal cell carcinoma of the skin, in situ cervical cancer, adequately treated stage I/II cancer from which the patient is current in complete remission, or any other cancer from which the patient has been disease free for five years
* Patients with history or presence of clinically significant neurological disorders such as epilepsy, generalized seizure disorder, or severe brain injuries.
* Any other issue which, in the opinion of the treating physician, would make the patient ineligible for the study.