Epacadostat and Vaccine Therapy in Treating Patients With Stage III-IV Melanoma

PRIMARY OBJECTIVES: I. To determine the extent to which a regimen of INCB024360 (epacadostat) that normalizes serum kynurenine (Kyn)/ tryptophan (Trp) ratios alters the tumor microenvironment of melanoma, including determining the number and character of tumor-infiltrating lymphocytes as determined by examination of serial biopsies with immunohistochemistry (IHC) and gene signatures. II. To determine the extent to which continued INCB024360 treatment plus the addition of the multipeptide melanoma vaccine, MELITAC 12.1 (MELITAC 12.1 peptide vaccine), further alters the tumor microenvironment of melanoma, including determining the number and character of tumor-infiltrating lymphocytes as determined by serial biopsies evaluating IHC and gene signatures. SECONDARY OBJECTIVES: I. To determine whether a regimen of INCB024360 that normalizes serum Kyn/Trp ratios plus MELITAC 12.1 vaccine changes the level or character of the vaccine-induced clusters of differentiation (CD) 8+ and CD4+ T-cell immune responses as measured in peripheral blood, as compared to prior published experience. II. To evaluate the extent to which INCB024360 plus MELITAC 12.1 vaccine alters the number and character of peripheral blood mononuclear cell (PBMC) populations, including T and natural killer (NK) cells, as evaluated by multiparameter flow cytometry. III. To evaluate the extent to which INCB024360 plus MELITAC 12.1 vaccine alters the PBMC transcriptome. IV. To assess the safety and tolerability of INCB024360 plus MELITAC 12.1 vaccine. V. To obtain preliminary data on the tumor response rate of INCB024360 plus MELITAC 12.1 vaccine by objective response rate (ORR), time to tumor progression, and overall survival. VI. To associate any observed changes with the expression of IDO1 protein by IHC in tumor or tumor-infiltrating cells. OUTLINE: Patients receive epacadostat orally (PO) twice daily (BID) on days 1-98 and receive MELITAC 12.1 peptide vaccine intradermally (ID)/subcutaneously (SC) on days 21, 28, 35, 56, 77, and 98. Treatment with epacadostat may repeat every 98 days for up to 3 additional courses in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up for 1 year.