Inclusion Criteria:

1. Aged 16 years or over

2. Confirmed diagnosis of recurrent or refractory B-precursor ALL [according to the WHO
classification].

3. Greater than 5% blasts in the bone marrow

4. WHO/ECOG performance status of 0-2 and well enough to receive intensive combination
chemotherapy.

5. Negative pregnancy test in women of childbearing potential. Women will not be
considered of child bearing potential if they have undergone surgical removal of the
uterus or are post menopausal and have been amenorrhoeic for at least 24 months.

6. Patients must have adequate organ function:

- Renal function - serum creatinine <2.5 x ULN or eGFR>50ml/min (measured EDTA
or estimated creatinine clearance e.g Cockcroft & Gault)

- Liver function (bilirubin/ALT <2.5 x ULN)

7. Patients must be able to comply with the study schedule.

Exclusion Criteria:

1. Patients should not have received chemotherapy for current episode of relapsed ALL
(except corticosteroids for a maximum of 10 days, before joining the study).

2. Patients with co-morbidities: e.g. uncontrolled hypertension and or poorly controlled
diabetes which in the PI's opinion makes them unsuitable for the study.

3. Patients with severe psychiatric disorders which in the PI's opinion makes them
unsuitable for trial participation.

4. Females of childbearing potential and all males must be willing to use an effective
method of contraception (hormonal or barrier method of birth control; abstinence) for
the duration of the study and for up to 3 months after the last dose of study
medication. Note: Subjects are not considered of child bearing potential if they are
surgically sterile (they have undergone a hysterectomy, bilateral tubal ligation, or
bilateral oophorectomy) or they are postmenopausal.

5. Females of childbearing potential must have a negative pregnancy test within 7 days
prior to starting the study.

6. Females must not be breastfeeding.

7. Patients may not receive any other investigational agent during the study.

8. Patients should not have received any antibody therapy within 3 months of joining
this study.