The primary objective is to determine the maximum tolerated dose (MTD) of SAR3419 according to the dose limiting toxicities (DLTs) observed when administered as a single agent once weekly.

Secondary objectives are:

• to characterize the global safety profile
• to evaluate the pharmacokinetic (PK) profile of SAR3419 in the proposed dosing schedule
• to assess preliminary evidence of anti-lymphoma activity.

Inclusion Criteria:

• Diagnosis of B-cell non Hodgkin's lymphoma
• Relapsed or refractory after standard treatments and with no curative option with conventional therapy (Patients having undergone stem cell transplantation may be included)
• CD19 positive disease by flow cytometry or immunohistochemistry

Exclusion Criteria:

• Burkitt's lymphoma, Lymphoblastic lymphoma, Chronic lymphocytic leukemia (Small lymphocytic lymphoma may be included)
• Evidence of cerebral or meningeal involvement by lymphoma
• Patients without bi-dimensionally measurable disease
• ECOG performance status > 2
• Life expectancy less than 3 months
• Chemotherapy or radiation therapy or other investigational agents within 4 weeks prior to entering the study
• Previous radioimmunotherapy within 12 weeks
• Known anaphylaxis to infused proteins
• HIV, HBV and HCV positivity
• Poor kidney, liver and bone marrow functions
• Any serious active disease or co-morbid condition, which, in the opinion of the principle investigator, will interfere with the safety or the compliance with the study
• Pregnant or breast-feeding women
• Patients with reproductive potential without effective birth control methods

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.