Study of IDO Inhibitor in Combination With Checkpoint Inhibitors for Adult Patients With Metastatic Melanoma

Inclusion Criteria: * Unresectable Stage III or Stage IV melanoma. * Patients must have measurable disease, defined as lesions that can be accurately measure in in 2 perpendicular diameters with at least one diameter \> 20mm and the other \>10mm on conventional CT or MRI or 10mm x 10 mm by spiral CT. * No systemic treatment in the previous 28 days. * Age ≥18 years. Because no dosing or adverse event data are currently available on the use of ipilimumab or indoximod in patients \<18 years of age, children are excluded from this study. * ECOG performance status ≤2 (Karnofsky ≥60% ) * Patients with known brain metastases will only be eligible after their tumors have been treated with definitive resection and/or radiotherapy and they are neurologically stable for at least 1 month off steroids. Exclusion Criteria: * Patients who have had molecular targeted therapy (including vemurafenib) or radiotherapy within 4 weeks prior to entering the study or those who have not recovered from adverse events due to agents administered more than 4 weeks earlier. * Patients who have had prior therapy with immune checkpoint inhibition or or indoximod are excluded from the trial. * Any other cancer, unless the patient has been disease-free for ≥5 years * Patients with laboratory evidence of pancreatitis are excluded. * Patients with autoimmune disease * Chronic use of immune-suppressive drugs (ie, systemic corticosteroids used in the management of cancer or non-cancer related illnesses, eg, CO…