Inclusion Criteria

Inclusion criteria:

- At least one measurable cancerous lesion in the brain from primary non-small cell
lung cancer (NSCLC)

- Must have received previous chemotherapy

- Must be 18 years of age of greater

- Must be Easter Cooperative Oncology Group (ECOG) Performance Status 0, 1, 2

- At least 2 weeks must have elapsed since any surgery

- At least 4 weeks must have elapsed since any radiation to a non-CNS site

- Must have adequate bone marrow, renal, and live capacities

- Women must be of non-childbearing potential or practice adequate birth control

- Males must practice adequate methods of birth control

- Must sign written informed consent

Exclusion criteria:

- Previous whole brain radiation therapy

- Prior treatment with topotecan

- Investigational agent within 30 days or 5 half-live

- Concomitant therapy with inhibitors of breast cancer resistance protein (BCRP) or
P-glycoprotein such as erlotinib or gefitinib

- Primary or secondary immunodeficiencies

- Gastrointestinal conditions that affect GI absorption or motility

- Uncontrolled emesis

- Brain metastasis at time of initial diagnosis of NSCLC

- History of other malignancy except in situ carcinoma of cervix; nonmelanomatous skin
cancer, low grade prostate cancer

- Pregnant or intending to become pregnant or intending to father a baby

- Any severe concurrent medical condition that could affect compliance.