Ipilimumab and Rituximab in Treating Patients With Relapsed or Refractory B-cell Lymphoma

PRIMARY OBJECTIVES: I. To determine a recommended phase II dose for ipilimumab in combination with rituximab. SECONDARY OBJECTIVES: I. To obtain preliminary information on the effect of adding ipilimumab to rituximab in regard to: immune response; clinical anti-tumor response/overall remission rate (ORR) (complete remission + partial remission); progression free survival (PFS). OUTLINE: This is a dose-escalation study of ipilimumab followed by a randomized study. PART I: INDUCTION: Patients receive ipilimumab intravenously (IV) over 90 minutes once every 3 weeks for 12 weeks and rituximab IV over 2-6 hours once weekly for 4 weeks. MAINTENANCE: Patients receive ipilimumab IV over 90 minutes and rituximab IV over 2-6 hours once every 12 weeks for up to 1 year. PART II: Patients are randomized to 1 of 2 treatment arms. ARM A: Patients receive rituximab IV over 2-6 hours once weekly in weeks 1-4 and ipilimumab IV over 90 minutes once weekly in weeks 1, 4, 7, and 10. Patients then receive ipilimumab IV over 90 minutes and rituximab IV over 2-6 hours once every 12 weeks for up to 1 year in the absence of disease progression or unacceptable toxicity. ARM B: Patients receive rituximab IV over 2-6 hours once weekly in weeks 1-4 and ipilimumab IV over 90 minutes once weekly in weeks 3, 6, 9, and 12. Patients then receive ipilimumab IV over 90 minutes and rituximab IV over 2-6 hours once every 12 weeks for up to 1 year in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up for 12 months.