4. Active central nervous system (CNS) metastases (indicated by clinical symptoms, cerebral edema, steroid requirement, or progressive disease). Subjects with brain or meningeal metastases that were previously treated must be clinically stable (magnetic resonance imaging [MRI] at least 4 weeks apart do not show evidence of new or enlarging metastases) and have discontinued immunosuppressive doses of systemic steroids (> 10 mg/day prednisone or equivalent) for at least 2 weeks before study drug administration.