- Participants with symptomatic brain metastases will be excluded from this clinical trial because of their poor prognosis and because they often develop progressive neurologic dysfunction that would confound the evaluation of neurologic and other adverse events. Subjects with asymptomatic, stable brain metastases and/or who have been previously treated for these conditions that are asymptomatic in the absence of corticosteroid therapy are allowed to enroll. Brain metastasis must be stable with verification by imaging (brain MRI completed at screening demonstrating no current evidence of progressive brain metastases.