- Patients with untreated brain metastases, spinal cord compression, or evidence of symptomatic brain metastases or leptomeningeal disease as noted on computed tomography (CT) or magnetic resonance imaging (MRI) scans are ineligible; screening imaging to rule out brain metastases is not required for screening, but should be performed prior to study enrollment if clinically indicated; patients with treated brain metastases must demonstrate stable post-therapeutic imaging and resolution of any associated symptoms and must be stably off steroids with no symptoms for at least 6 months following therapy prior to starting study drug