Testing the Addition of an Experimental Medication MK-3475 (Pembrolizumab) to Usual Anti-Retroviral Medications in Patients With HIV and Cancer

This phase I trial studies the side effects of pembrolizumab in treating patients with human immunodeficiency virus (HIV) and malignant neoplasms that have come back (relapsed), do not respond to treatment (refractory), or have distributed over a large area in the body (disseminated). Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread.

PRIMARY OBJECTIVES: I. To assess the safety and tolerability of MK-3475 (pembrolizumab) in HIV-infected patients on effective antiretroviral therapy and with relapsed/refractory or disseminated acquired immune deficiency syndrome (AIDS)-defining or non-AIDS defining malignancy. II. To assess the safety and feasibility of MK-3475 (pembrolizumab) administration as first systemic therapy for HIV associated Kaposi sarcoma in patients on effective antiretroviral therapy. SECONDARY OBJECTIVES: I. To obtain preliminary insights into clinical benefit (e.g., tumor shrinkage or stabilization \>= 24 weeks) across a variety of tumors in patients infected with HIV and on effective antiretroviral therapy. II. To evaluate the response rate in Kaposi sarcoma impacting physical and/or psychological wellbeing and not amenable to local therapy. EXPLORATORY OBJECTIVES: I. To assess the correlation of pre-therapy tumor PD-L1 expression and T-cell infiltration on clinical benefit. II. To assess the effect of MK-3475 (pembrolizumab) on circulating HIV and the HIV viral reservoir in patients on effective combination anti-retroviral therapy (cART), as measured by plasma HIV single copy ribonucleic acid (RNA), CD4+ T-cell associated HIV unspliced RNA, CD4+ T-cell associated integrated HIV deoxyribonucleic acid (DNA) provirus, ratio of HIV unspliced RNA/DNA, "Tat/Rev induced limiting dilution assay" (TILDA), and phylogenetic analysis of HIV-1 molecular evolution. III. To evaluate the effect of MK-3475 (pembrolizumab) on host gene expression in circulating blood cells. IV. To evaluate the effect of MK-3475 (pembrolizumab) on circulating HIV-specific CD8+ T-cell cytotoxicity against autologous HIV infected CD4+ T-cells in patients on effective antiretroviral therapy. V. To evaluate the effect of MK-3475 (pembrolizumab) on circulating lymphocyte and monocyte numbers and phenotypes. VI. To assess biopsied tumors from participants that progress by immunohistochemistry arrays and gene expression analysis to evaluate potential reasons for the lack of response to MK-3475 (pembrolizumab) or progression such as a lack of T cells within or around tumor. VII. To evaluate the effect of pembrolizumab on human herpesvirus 8 (KSHV) viral load in the blood, KSHV seroreactivity and KSHV specific CD8+ T-cell activity. OUTLINE: Patients receive pembrolizumab intravenously (IV) over 30 minutes on day 1. Patients continue receiving their recommended combination antiretroviral therapy orally (PO) once daily (QD). Cycles repeat every 21 days for up to 2 years or 35 doses in the absence of disease progression or unacceptable toxicity. Patients also undergo computed tomography (CT) or positron emission tomography (PET)/CT and blood sample collection throughout the trial. Patients may also undergo biopsies during screening and on study. After completion of study treatment, patients are followed up 30 days and then every 12 weeks up to 1 year.