- Subject has primary central nervous system (CNS) tumor or known CNS metastases and/or history of CNS metastases and/or carcinomatous meningitis; Exception: Subjects are eligible if CNS metastases are adequately treated and subjects are neurologically returned to baseline (except for residual signs or symptoms related to the CNS treatment) for at least 4 weeks prior to enrollment. In addition, subjects must be off corticosteroids for 4 weeks prior to enrollment.