Inclusion Criteria: - confirmed diagnosis of NSCLC - Stage IIIB or IV NSCLC - ECOG Performance Status 0 or 1 - Prior therapy defined as 1 prior systemic therapy for advanced disease - measurable disease - Radiologic evidence of disease progression following most recent prior treatment. - Adequate hematologic, hepatic, renal function Exclusion Criteria: - Active or untreated CNS metastases - Active malignancies other than NSCLC within the last 5 years with the exception of adequately treated cone-biopsied in situ carcinoma of the cervix uteri or basal or squamous cell carcinoma of the skin - Serious cardiac illness or medical conditions - Pregnant or lactating women - Uncontrolled intercurrent illness