Testing a Reduced Conditioning Regimen FB2A2 Preceded by a Fractionated Radio-immunotherapy (RIT) With 90Y-Epratuzumab Before Allogeneic Stem Cell Transplantation for Patients With Lymphocyte B CD22 Positive Acute Lymphoblastic Leukemia

Determination of the maximum tolerated dose (MTD) of fractionated RIT with epratuzumab radiolabeled with yttrium-90 (90Y-epratuzumab) preceding a reduced conditioning regimen FB2A2 before allogeneic stem cell transplantation.

• Physical examination (screening and follow-up)
• Complete blood counts (screening and follow-up)
• Dosage of FLT3-ligand in plasma (screening and follow-up)
• Blood ionogramme, creatinine hepatic work-up (screening and follow-up)
• Left ventricular ejection fraction at pre-implant assessment
• Immunization test (screening and follow-up)
• Bone marrow aspiration or/and blood CD 22 immunophenotype for minimal residual disease evaluation (screening and follow-up)
• All exams which were initially abnormal and which are necessary for response evaluation and All exams which are needed in case of relapse suspicion.
• Pharmacokinetic of 90Y-hLL2

Inclusion Criteria:

• Age ≥ 18
• Acute lymphoblastic Leukemia (ALL) CD22 + B-type in RC1 with high risk
• B-Cell Acute Lymphoblastic Leukemia (ALL) CD22+ beyond RC1.
• Expression of CD22 ≥ 30% in tumor population evaluated by flow cytometry or immunohistochemistry at diagnosis stage or relapse stage.
• HLA-identical donor intra family or not, without major HLA mismatch (9 / 10th accepted) without contra-indication for stem cell mobilization
• ECOG (Eastern Cooperative Oncology Group) ≤ 2
• Having or not received previously Epratuzumab
• Eligible for an allograft with reduced conditioning regimen
• With a signed informed consent
• Patient in age of children bearing with adequate contraception
• Patient affiliated to or beneficiary of the National Health Service

Exclusion Criteria:

• T-cell ALL
• Known hypersensibility to 90Y-DOTA-hLL2
• Immunization against hLL2 for patients having already received one or several injections of this antibody
• Patient eligible for myeloablative conditioning regimen
• Other prior malignancies must have had at least a 2-year disease-free interval with the exception of successfully treated carcinoma skin cancer or carcinoma in situ of the cervix.
• Patient with progressive psychiatric condition.
• HIV positive, hepatitis B-antigen positive, or hepatitis C positive patients who need a treatment
• Pregnant or breast-feeding women
• Women with childbearing potential without effective contraception
• Serious concomitant and uncontrolled infection
• Usual contraindications in the allogeneic transplant:
• Adult patient protected by the French law