A Study of the Safety, Tolerability, and Efficacy of Epacadostat Administered in Combination With Nivolumab in Select Advanced Cancers (ECHO-204)

Inclusion Criteria: * Male or female subjects, age 18 years or older * Subjects with histologically or cytologically confirmed NSCLC, MEL (including I/O relapsed MEL or I/O refractory MEL), CRC, SCCHN, ovarian cancer, recurrent B cell NHL or HL, or glioblastoma * Presence of measurable disease by RECIST v1.1 for solid tumors or Cheson criteria for B cell NHL (including DLBCL) or HL. For subjects with glioblastoma, presence of measurable disease is not required. * Eastern Cooperative Oncology Group (ECOG) performance status 0 to 1 * Fresh baseline tumor biopsies (defined as a biopsy specimen taken since completion of the most recent prior chemotherapy regimen) are required for all cohorts except glioblastoma Exclusion Criteria: * Laboratory and medical history parameters not within Protocol-defined range * Currently pregnant or breastfeeding * Subjects who have received prior immune checkpoint inhibitors or an IDO inhibitor (except select Phase 2 cohorts evaluating I/O relapsed or I/O refractory MEL). Subjects who have received experimental vaccines or other immune therapies should be discussed with the medical monitor to confirm eligibility * Untreated central nervous system (CNS) metastases or CNS metastases that have progressed * Subjects with any active or inactive autoimmune process * Evidence of interstitial lung disease or active, noninfectious pneumonitis * Subjects with any active or inactive autoimmune process * Ocular MEL