Inclusion Criteria:

          1. Male or female patients, ≥56 years of age and fit for therapy

          2. Newly diagnosed acute lymphoblastic leukemia (>25% marrow blasts, assessed by
             morphology; i.e. M3 marrow)

          3. Leukemic blasts must have CD22 surface expression of a least 20%, assessed by
             local/institutional flow cytometry of a bone marrow aspirate sample (assessment of
             CD22 via the reference lab for immungenetics is strongly recommended). In the case of
             an inadequate aspirate sample (dry tap), flow cytometry of peripheral blood specimen
             may be substituted if the patient has circulating blasts; alternatively, CD22
             expression may be documented by immunohistochemistry of a bone marrow biopsy specimen

          4. No previous ALL-specific treatment with the exception of corticosteroids and/or single
             dose vincristine and/or a maximum of three doses of cyclophosphamide (cumulative dose
             of 600mg/m2) and the standard prephase treatment

          5. With or without documented CNS involvement

          6. Adequate liver function, including total serum bilirubin <2.0 x ULN unless the patient
             has documented Gilbert syndrome, and aspartate and alanine aminotransferase (AST and
             ALT) <2.5 x ULN If organ function abnormalities are considered due to leukemic
             infiltration of the liver, total serum bilirubin must be < 2.5 x ULN and AST/ALT <5 x
             ULN

          7. Serum creatinine <1.5 x upper limit of normal (ULN) or any serum creatinine level
             associated with a measured or calculated creatinine clearance of >40 mL/min

          8. WHO performance status ≤ 2

          9. Signed written inform consent

         10. Inclusion in GMALL registry

        Exclusion Criteria:

          1. Philadelphia-chromosome or BCR-ABL positive ALL

          2. Burkitt's or mixed phenotype acute leukemia based on the WHO 2008 criteria

          3. Peripheral absolute lymphoblast count >10,000/μL after pre-phase treatment and before
             start of study medication

          4. Known systemic vasculitis (e.g. , Wegener's granulomatosis, polyarteritis nodosa,
             systemic lupus erythematosus), primary or secondary immunodeficiency (such as HIV
             infection or severe inflammatory disease)

          5. Current or chronic hepatitis B or C infection as evidenced by hepatitis B surface
             antigen and anti-hepatitis C antibody positivity, respectively, or known
             seropositivity or human immunodeficiency virus (HIV)

          6. Major surgery within <4 weeks before entry on study

          7. Unstable or severe uncontrolled medical condition (e.g., unstable cardiac function or
             unstable pulmonary condition)

          8. Concurrent active malignancy other than non-melanoma skin cancer, carcinoma in situ of
             the cervix, or localized prostate cancer that has been definitely treated with
             radiation or surgery; patients with previous malignancies are eligible provided that
             they have been disease free for >2 years

          9. Cardiac function, as measured by left ventricular ejection fraction (LVEF) that is
             less than 45%, or the presence of New York Heart Association (NYHA) stage III or IV
             congestive heart failure

         10. Myocardial infarction <6 months before randomization

         11. History of clinically significant ventricular arrhythmia, or unexplained syncope not
             believed to be vasovagal in nature, or chronic bradycardic states such as sinoatrial
             block or higher degrees of AV block unless a permanent pacemaker has been implanted

         12. Uncontrolled electrolyte disorders that can confound the effects of a QTc prolonging
             drug (e.g., hypokalemia, hypocalcemia, hypomagnesemia)

         13. History of chronic liver disease (e.g., cirrhosis) or suspected alcohol abuse

         14. History of hepatic veno-occlusive disease (VOD) or sinusoidal obstruction syndrome
             (SOS)

         15. Administration of live vaccine <6 weeks before randomization

         16. Evidence of uncontrolled current serious active infection (including sepsis,
             bacteremia, fungemia) or patients with a recent history (within 4 months) of deep
             tissue infections such as fasciitis or osteomyelitis

         17. Patients who have had a severe allergic reaction or anaphylactic reaction to any
             humanized monoclonal antibodies or any known hypersensitivity to the active substance
             or any of its excipients

         18. Pregnant females; breastfeeding females; males and females of childbearing potential
             (a woman is considered of childbearing potential (WOCBP) i.e. fertile, following
             menarche and until becoming post-menopausal unless permanently sterile e.g. after
             hysterectomy or bilateral ovariectomy. Please refer to chapter 12.4 Contraceptive
             Requirements.) not using highly effective contraception or not agreeing to continue
             highly effective contraception for women at least 8 months an for men at least 5
             months after the last dose of investigational product

         19. Participation in other studies involving investigational drug(s) (Phase I-IV) within 4
             weeks before study inclusion

         20. Other severe acute or chronic medical or psychiatric condition or laboratory
             abnormality that may increase the risk associated with study participation or
             investigational product administration or may interfere with the interpretation of
             study results and, in the judgment of the investigator, would make the patient
             inappropriate for entry into this study.