Ixazomib & Rituximab After Stem Cell Transplant in Treating Patients With Mantle Cell Lymphoma in Remission

PRIMARY OBJECTIVES: I. To determine the recommended phase II dose and assess the safety of ixazomib when administered as post-transplant maintenance in mantle cell lymphoma and to evaluate the safety of rituximab in combination with the recommended phase II dose (RP2D) of ixazomib. (Phase I) II. To assess preliminary evidence of efficacy of ixazomib in combination with rituximab when administered as post-transplant maintenance in mantle cell lymphoma. (Phase II) SECONDARY OBJECTIVES: I. To evaluate for preliminary evidence of efficacy of ixazomib (+/- rituximab) maintenance therapy in patients with mantle cell lymphoma undergoing autologous stem cell transplant in first partial or complete remission. (Phase I) II. To evaluate for preliminary evidence of efficacy of ixazomib (+/- rituximab) maintenance therapy in patients with mantle cell lymphoma who have a complex karyotype and other high-risk cytogenetic or clinical markers. (Phase I) III. To evaluate toxicities associated with prolonged administration of ixazomib maintenance therapy in patients with mantle cell lymphoma (MCL). (Phase I) IV. To evaluate the rate of minimal residual disease (MRD) in patients who have completed an autologous transplant for mantle cell lymphoma and to assess the impact of MRD on outcomes for patients receiving maintenance therapy. (Phase I) V. To evaluate efficacy of ixazomib with rituximab maintenance therapy in patients with MCL who undergo autologous stem cell transplantation in first remission who have a complex karyotype and/or additional high risk cytogenetic or clinical features at diagnosis. (Phase II) VI. To further evaluate safety and toxicity of prolonged administration of ixazomib. (Phase II) VII. To evaluate long-term disease-related and survival outcomes for patients with MCL who receive post-transplant maintenance therapy with ixazomib with rituximab. (Phase II) VIII. To evaluate the rate of minimal residual disease (MRD) in patients who have completed an autologous transplant for mantle cell lymphoma and to assess the impact of MRD on outcomes for patients receiving maintenance therapy. (Phase II) TERTIARY OBJECTIVES: I. To evaluate the prognostic value of pre-transplant positron emission tomography (PET)/computed tomography (CT) in mantle cell lymphoma. II. To evaluate the ability of the single nucleotide polymorphism (SNP) array to identify high-risk cytogenetic features in patients with MCL. III. To evaluate the impact of ixazomib maintenance (+/- rituximab) on immunoglobulin levels for patients completing autologous stem cell transplantation for mantle cell lymphoma. OUTLINE: This is a phase I, dose-escalation study of ixazomib followed by a phase II study. Beginning between 70-180 days after stem cell transplant, patients receive ixazomib orally (PO) on days 1, 8, and 15, and rituximab intravenously (IV) (or subcutaneously \[SC\] after first dose if deemed appropriate) on day 1 of courses 1, 3, 5, 7, and 9. Treatment repeats every 28 days for up to 10 courses in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up every 6 months for up to 2 years.