A Study of Onartuzumab in Combination With Erlotinib in Patients With MET-Positive Stage IIIB or IV Non-Small Cell Lung Cancer Carrying an Activating Epidermal Growth Factor Receptor (EGFR) Mutation

Inclusion Criteria: * Adult patient, \>/= 18 years of age * Histologically confirmed, unresectable Stage IIIB or IV non-small cell lung cancer (NSCLC) * No prior treatment for unresectable Stage IIIB or IV NSCLC * Measurable radiographic evidence of disease according to RECIST v1.1 * Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 Exclusion Criteria: * Prior exposure to agents targeting either the Hepatocyte Growth Factor (HGF) or MET pathway * Exposure to an investigational or marketed agent that can act by EGFR inhibition * Pleural effusion, pericardial fluid, or ascites requiring drainage every other week or more frequently * Brain metastasis or spinal cord compression not definitively treated with surgery and/or radiation, or previously diagnosed and treated central nervous system (CNS) metastases or spinal cord compression without evidence of clinically stable disease for \>/=4 days. Note: Patients with treated CNS metastases who are asymptomatic and on a stable dose of corticosteroids for \>/= 14 days prior to randomization are eligible. * History of another malignancy in the previous 5 years, unless cured by surgery alone and continuously disease-free * Radiographically evident interstitial lung disease , concurrent infection, or a history of any of these conditions * Inadequate hematologic, biochemical, and organ function * Pregnant or lactating women * Life expectancy of \< 12 weeks * Receipt of an investigational drug within 28 days prior to initiation of study treatment