Subjects will be assigned to a set of treatment groups depending on their eligibility to receive bevacizumab. Subjects with squamous NSCLC and/or CNS metastases will not be eligible to receive bevacizumab and will be assigned to either cohort A or B (provided all other eligibility criteria are met). Subjects who are eligible to receive bevacizumab will be assigned to cohort C, D or E. Cohorts are defined as follows: