Osimertinib With or Without Bevacizumab as Initial Treatment for Patients With EGFR-Mutant Lung Cancer

PRIMARY OBJECTIVE: I. To evaluate progression-free survival (PFS) of osimertinib (AZD9291) and bevacizumab versus osimertinib (AZD9291) alone as first-line treatment for patients with metastatic EGFR-mutant lung cancers. SECONDARY OBJECTIVES: I. To evaluate overall survival (OS). II. To evaluate best objective response rate and duration of objective response. III. To evaluate time to central nervous system (CNS) progression and CNS PFS. IV. To evaluate toxicity of the combination regimen. CORRELATIVE OBJECTIVES: I. To characterize mechanisms of resistance to osimertinib (AZD9291) and osimertinib (AZD9291) with bevacizumab first-line therapy through post-progression circulating tumor-derived deoxyribonucleic acid (ctDNA). II. To assess for ctDNA clearance on study treatment and associate ctDNA clearance with clinical outcomes. OUTLINE: Patients are randomized to 1 of 2 arms. ARM A: Patients receive osimertinib orally (PO) once daily (QD) on days 1-21. Cycles repeat every 21 days in the absence of disease progression or unacceptable toxicity. ARM B: Patients receive osimertinib PO QD on days 1-21 and bevacizumab intravenously (IV) over 30-90 minutes on day 1. Cycles repeat every 21 days in the absence of disease progression or unacceptable toxicity. Patients undergo echocardiography (ECHO), multigated acquisition scan (MUGA), computed tomography (CT) and may undergo magnetic resonance imaging (MRI) and blood and urine sample collection on study. After completion of study treatment, patients are followed up every 3 months for 10 years.