Inclusion Criteria:  Histologically confirmed NSCLC (e.g., adenocarcinoma, squamous cell) deemed unresectable or inoperable who have received concurrent chemoradiation followed by Durvalumab consolidation. Disease progression during or within 3 months of completion of Durvalumab treatment. Have at least one measurable lesion. ECOG performance status ≤2. Adequate organ and marrow function. Ability to understand and the willingness to sign a written informed consent document.  Exclusion Criteria:  Mixed Non-small cell and small cell histology; known EGFR and/or ALK driver mutations. Treated with sequential chemoradiation therapy. Autoimmune disease, such as rheumatoid arthritis, systemic lupus erythematosus, requiring systemic treatment with immunosuppressant in the past two years. Patients who are receiving any other investigational agents orally or intravenously. Systemic steroid for other purpose exceeding 10 mg prednisone a day except local injection at the discretion of the investigator. Solid organ or bone marrow transplant recipients. History or concurrent condition of interstitial lung disease of any severity and/or severely impaired lung function. Patients with uncontrolled inter-current illness. Patients with psychiatric illness/social situations that would limit compliance with study requirements and patients with seizure disorder not well controlled. Received live vaccine in the past 4 weeks. Pregnant or breast-feeding/lactating women. Receiving medications prohibited by the study. Left ventricular ejection fraction less than 40%. New York Heart Association Class 3 or above. Myocardial infarction within the last 6 months. Unstable angina. Venous thromboembolism within last 3 months. Evidence or history of bleeding diathesis. Any hemorrhage or bleeding event ≥ CTCAE Grade 3 within 4 weeks. Proteinuria of ≥ CTCAE Grade 3 or estimated by urine protein: creatinine ratio > 3.5 Major surgeries within the last 28 days. Any illness or medical conditions that are unstable or could jeopardize the safety of patients and their compliance in the study.