Trial Information

Title: Evaluation of Systemic IDO Levels After Various Immunotherapeutics

OBJECTIVES:

- To determine how a variety of immune-modulating therapies (i.e., interferon alfa
[IFN-α] in patients with untreated acute or chronic hepatitis C, anti-tumor necrosis
factor in patients with active inflammatory bowel disease (i.e., Crohn disease), and
anticytotoxic T-lymphocyte antigen immunoglobulin in patients with metastatic melanoma)
affect the tissue expression of indoleamine 2, 3 dioxygenase (IDO), a major
immune-regulatory mechanism.

- To determine whether administration of pegylated INF-α in patients with untreated acute
and chronic hepatitis C causes systemic changes in the IDO pathway, as indicated by
lowered serum tryptophan (TRP) and elevated serum kynurenine (KYN).

- To determine whether administration of ticilimumab (i.e., anti-CTLA4 human monoclonal
antibody CP-675,206) in patients with metastatic melanoma inhibits activation of the
IDO pathway as indicated by normal serum TRP and normal serum KYN.

- To determine whether administration of infliximab in patients with Crohn disease
inhibits activation of the IDO pathway, as indicated by normal serum TRP and normal
serum KYN.

OUTLINE: Serum samples are collected from patients with hepatitis C and metastatic melanoma
at baseline and at 3 to 4 weeks after treatment is initiated. Previously collected samples
from patients with Crohn disease are also assessed at these time points. Samples are
analyzed for tryptophan and kynurenine levels via high-performance liquid chromatography.

PROJECTED ACCRUAL: A total of 15 patients with untreated acute or chronic Hepatitis C, 15
patients with metastatic melanoma, and 20 patients with Crohn disease will be accrued for
this study.