PACIFIC-4: This study is assessing how safe and effective immunotherapy plus radiation therapy is, compared to placebo and radiation therapy, in people with lymph-node negative non-small cell lung cancerA Phase III, Randomized, Placebo-controlled, Double-blind, Multi-center, International Study of Durvalumab With Stereotactic Body Radiation Therapy (SBRT) for the Treatment of Patients With Unresected Stage I/II, Lymph-node Negative Non-small Cell Lung Cancer (PACIFIC-4/RTOG-3515) Osimertinib Following SBRT, a Single Arm Cohort for Patients With Unresected Stage I/II, Lymph Node Negative NSCLC Harboring a Sensitizing EGFR Mutation

Exclusion

Main Cohort Key Exclusion Criteria:

1. Mixed small cell and non-small cell cancer
2. History of allogeneic organ transplantation
3. History of another primary malignancy with exceptions
4. History of active primary immunodeficiency
5. Epidermal growth factor receptor local testing is strongly recommended prior to enrollment. Patients with a tumor harboring an EGFRm per local testing will be excluded from the main cohort
6. Prior exposure to immune-mediated therapy with exceptions

Osimertinib Cohort Key Exclusion Criteria

1. Mixed small cell and non-small cell cancer
2. Patients currently receiving potent inducers of CYP3A4
3. Patients with known or increased risk factor for QTc prolongation

4. Treatment with any of the following:

   • Preoperative or adjuvant platinum-based or other chemotherapy for the disease under investigation
   • Prior treatment with neoadjuvant or adjuvant EGFR TKI
   • Patients currently receiving (or unable to stop use prior to receiving the first dose of study treatment) medications or herbal supplements known to be potent inducers of CYP3A4
   • Refractory nausea and vomiting, chronic gastrointestinal diseases, inability to swallow the formulated product, or previous significant bowel resection that would preclude adequate absorption of osimertinib

5. Any of the following cardiac criteria

   • Mean resting corrected QT interval >470 msec, obtained from 3 ECGs
   • Any clinically important abnormalities in rhythm, conduction, or morphology of resting ECG.
   • Any factors that increase the risk of QTc prolongation or risk of arrhythmic events, or unexplained -sudden death under 40 years of age in first-degree relatives or any concomitant medication known to prolong the QT interval
   • Past medical history of ILD, drug-induced ILD, radiation pneumonitis which required steroid treatment, or any evidence of clinically active ILD