Carfilzomib With Bendamustine and Rituximab in Patients With Relapsed or Refractory Non-Hodgkin Lymphoma

Inclusion Criteria: * Histologically-confirmed B-cell non-Hodgkin's lymphoma (Mantle Cell Lymphoma, Follicular Lymphoma, Small Lymphocytic Lymphoma/Chronic Lymphocytic Leukemia, Marginal Zone Lymphoma, Diffuse Large B-cell Lymphoma, and Lymphoplasmacytic Lymphoma) * Must have relapsed or refractory disease after 2 or more prior lines of therapy; 1 line of therapy is allowed, if it included an autologous stem cell transplant and at least 12 weeks have elapsed from Day 0. A line of therapy is defined as a course of therapy that is not interrupted by progressive disease. * Subjects must have measurable disease of at least 1.5 cm in diameter * Age ≥ 18 years * Life expectancy ≥ 3 months * Eastern Cooperative Oncology Group (ECOG) performance status 0-2 * Females of childbearing potential (FCBP) must agree to ongoing pregnancy testing and to practice contraception. FCBP definition: A female of childbearing potential is a sexually mature woman who: 1) has not undergone a hysterectomy or bilateral oophorectomy; or 2) has not been naturally postmenopausal for at least 24 consecutive months. * Male subjects must agree to practice contraception for at least 90 days after the last dose of carfilzomib, and must agree not to donate sperm for at least 90 days after the last dose of carfilzomib Adequate bone marrow function: * Absolute neutrophil count ≥ 1.0 × 10\^9/L * Hemoglobin ≥ 8 g/dL (80 g/L) within 14 days prior Cycle 1, Day 1 (subjects may be receiving red blood cell (RBC) transfusions in accordance with institutional guidelines) * Platelet count ≥ 75 × 10\^9/L or≥ 50× 10\^9/L if there is lymphoma involvement in the bone marrow, independent of platelet transfusion Adequate hepatic function: * Serum aspartate aminotransferase (AST) /alanine aminotransferase (ALT) ≤ 3 times the upper limit of normal * Serum direct bilirubin ≤ 2 mg/dL (unless history of Gilbert's) Adequate renal function: * Creatinine clearance (CrCl) ≥ 30 mL/minute, either measured or calculated using a standard formula (eg, Cockcroft and Gault) * Uric acid If elevated, corrected to within laboratory range prior to dosing Exclusion Criteria: * Progressive disease on bendamustine within 6 months of cycle 1, Day 1 * Prior treatment with carfilzomib for lymphoma * Patient has received other investigational drugs within 21 days prior to Cycle 1, Day 1. Exceptions allowed if greater than four half-lives of the experimental agent ). * Prior radiation therapy or chemotherapy within 2 weeks prior Cycle 1, Day 1, monoclonal antibody therapy within 4 weeks * Prior allogeneic transplant * Active, uncontrolled central nervous system (CNS) involvement by lymphoma * Pregnant or lactating females * Major surgery within 14 days prior Cycle 1, Day 1 * Acute active infection requiring treatment (systemic antibiotics, antivirals, or antifungals) within 14 days prior Cycle 1, Day 1 * Known human immunodeficiency virus infection * Active hepatitis C infection (HCV), defined as presence of HCV antibody. * Unstable angina or myocardial infarction within 6 months prior Cycle 1, Day 1, New York Heart Association (NYHA) Class III or IV heart failure, left ventricular ejection fraction (LVEF) \< 40%, uncontrolled angina, history of severe coronary artery disease, history of torsade de pointes, history of symptomatic pulmonary hypertension, severe uncontrolled ventricular arrhythmias, sick sinus syndrome, QTc prolongation \>450 msec, or electrocardiographic evidence of acute ischemia or Grade 3 conduction system abnormalities unless subject has a pacemaker. * Uncontrolled hypertension or uncontrolled diabetes within 14 days prior Cycle 1, Day 1 * Nonhematologic malignancy within the past 3 years with the exception of a) adequately treated basal cell carcinoma, squamous cell skin cancer, or thyroid cancer; b) carcinoma in situ of the cervix or breast; c) prostate cancer of Gleason Grade 6 or less with stable prostate-specific antigen levels; or d) cancer considered cured by surgical resection or unlikely to impact survival during the duration of the study, such as localized transitional cell carcinoma of the bladder or benign tumors of the adrenal or pancreas * Significant neuropathy (Grades 3-4, or Grade 2 with pain) within 14 days prior Cycle 1, Day 1 * Known history of allergy to Captisol® (a cyclodextrin derivative used to solubilize carfilzomib) * Contraindication to any of the required concomitant drugs or supportive treatments, including hypersensitivity to all anticoagulation and antiplatelet options, antiviral drugs, or intolerance to hydration due to preexisting pulmonary or cardiac impairment * Subjects with pleural effusions requiring thoracentesis or ascites requiring paracentesis within 14 days prior Cycle 1, Day 1 * Any other clinically significant medical disease or condition that, in the Investigator's opinion, may interfere with protocol adherence or a subject's ability to give informed consent.