Pomalidomide and Dose-Adjusted EPOCH +/- Rituximab for HIV-Associated Lymphomas

Background: * Non-Hodgkin lymphoma (NHL) is the most common cancer among people living with human immunodeficiency virus (HIV) (PLWH) in the United States. Even in the modern era of antiretroviral therapy (ART), PLWH have an 11- to 17-fold higher risk of NHL than the general population due in part to CD4+ T-cell lymphopenia but also immune dysregulation and exhaustion from chronic viral antigen stimulation. * The most common NHL subtypes are diffuse large cell lymphoma (DLBCL) and Burkitt lymphoma (BL), that are much more frequently associated with the oncogenic virus Epstein Barr virus (EBV) in PLWH, which portends a poorer prognosis, than in the general population. * Plasmablastic lymphoma (PBL) is a rare CD20 negative B cell lymphoma associated with EBV almost exclusively seen in PLWH. * Although these subtypes of lymphoma occur in the general population, their presentation and pathogenesis may be different - meaning there may be different therapeutic targets and strategies to consider in HIV-associated lymphomas necessitating clinical trials targeted to this underserved population of patients. * Lenalidomide, a 2nd generation immunomodulatory drug, has shown safety and improved survival in combination with chemotherapy in advanced stage DLBCL in one of two randomized trials. * Pomalidomide, a 3rd generation immunomodulatory agent, has activity in primary central nervous system (CNS) lymphoma demonstrating its activity in both NHL and CNS involvement, which is more common in PLWH and NHL. In a number of parameters, it is more potent than lenalidomide. * Pomalidomide has shown to increase natural killer (NK) and T-cell activation and reverse T-cell senescence in addition to increasing CD4+ T-cell count in PLWH and cancer. It can also enhance expression of surface immune markers in vitro in cell lines from EBV-induced tumors. * Dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin (DA-EPOCH) along with rituximab (DA-EPOCH-R) is an anthracycline-based regimen that has been shown to be safe and effective in PLWH and in the most common subtypes of NHL seen in PLWH, DLBCL and BL. Objective: -Determine the safety and maximum tolerated dose (MTD) of the combination of pomalidomide and dose-adjusted EPOCH +/ rituximab (DA-EPOCH-RP) in participants with enrolled subtypes of HIV-associated lymphomas Eligibility: * Adult participants \>= 18 years with pathology-confirmed HIV-associated B-cell non-Hodgkin lymphoma with high-risk features, excluding primary CNS lymphoma * Positive HIV1/2 serology Design: * This is a phase 1 study of DA-EPOCH-RP in participants with HIV-associated B-cell non-Hodgkin lymphoma. Only participants with CD20+ HIV-associated B-cell non-Hodgkin lymphoma will receive Rituximab. * This is a dose escalation study to evaluate pomalidomide in combination with modified DA-EPOCH-R to determine safety and tolerability. Dosing will begin at dose level 1, 3 mg of pomalidomide and proceed to dose escalation or de-escalation to doses 4 mg or 2 mg depending on dose-limiting toxicities. * Participants will be prescribed ART. * In this phase I study, up to 12 evaluable participants will be accrued in the escalation phase (3-6 participants per level) and up to 6 evaluable participants will be accrued in the expansion phase to be treated at MTD.