Study Evaluating The Safety And Tolerability Of Combination Therapy Inotuzumab Ozogamicin (CMC-544) And Rituximab

• Drug: Inotuzumab Ozogamicin (CMC-544)
  
  1.8 mg/m2, IV on day 2 of each 28 day cycle; up to 8 cycles unless PD, unacceptable toxicity, or subject's refusal occurs.
• Drug: Rituximab (Rituxan)
  
  375 mg/m2, IV on day 1 of each 28 day cycle; up to 8 cycles unless PD, unacceptable toxicity, or subject's refusal occurs.

Inclusion Criteria:

• CD20 and CD22-positive, B-cell NHL which has progressed after 1 or 2 prior therapies.
• Prior therapy must have contained at least one dose of Rituximab therapy. Patients can not be refractory to Rituximab (refractory = PD under treatment or within 6 month
• Eastern Cooperative Oncology Group (ECOG) performance status: 0/ 1.
• Patients must not have received previous radioimmunotherapy.
• Patients tolerant to Rituximab.
• Patients must not have received chemotherapy, cancer immunosuppressive therapy, growth factors (except erythropoietin), or investigational agents within 28 days before first dose of test article.

Exclusion Criteria:

• Candidate for potentially curative therapies
• Subjects must not have received previous radioimmunotherapy.
• Subjects with autologous hematopoietic stem cell transplant within the last 6 months