Radiation Therapy Oncology Group (RTOG) 3505 is a randomized phase 3 study of concurrent chemoradiation followed by immune checkpoint inhibitor therapy or placebo in patients with locally advanced non-small-cell lung cancer (NSCLC). Patients with surgically unresectable stage 3 NSCLC will receive thoracic radiotherapy to 60 Gy with concurrent cisplatin 50 mg/m² intravenously (I.V.) on days 1, 8, 29, and 36, and etoposide 50 mg/m² I.V. on days 1 to 5 and days 29 to 33. Between 4 and 12 weeks after completion of concurrent chemoradiation, eligible patients will be randomized to the anti-programmed death 1 (PD-1) monoclonal antibody nivolumab 240 mg I.V. or placebo every 2 weeks for up to 1 year. The primary end points are overall survival (OS) and progression-free survival (PFS), as determined by central independent radiology review. Secondary objectives include toxicity assessment, patient-reported outcomes and quality of life, and OS and PFS in programmed death ligand 1 (PD-L1) expressors (≥ 1%) and PD-L1 nonexpressors (< 1%). Assuming a rate of 16.7% due to ineligibility and dropout before randomization, a total of 660 patients will be enrolled to ensure 550 patients will be randomized after completion of chemoradiation. This sample size will provide ≥ 90% power to detect a hazard ratio of 0.7 for OS with 2-sided type I error of 0.04, and to detect a hazard ratio of 0.667 for PFS 2-sided type I error of 0.01. (NCT02768558).

Although aberrant EGFR signaling is widespread in cancer, EGFR inhibition is effective only in a subset of non-small cell lung cancer (NSCLC) with EGFR activating mutations. A majority of NSCLCs express EGFR wild type (EGFRwt) and do not respond to EGFR inhibition. TNF is a major mediator of inflammation-induced cancer. We find that a rapid increase in TNF level is a universal adaptive response to EGFR inhibition in NSCLC, regardless of EGFR status. EGFR signaling actively suppresses TNF mRNA levels by inducing expression of miR-21, resulting in decreased TNF mRNA stability. Conversely, EGFR inhibition results in loss of miR-21 and increased TNF mRNA stability. In addition, TNF-induced NF-κB activation leads to increased TNF transcription in a feed-forward loop. Inhibition of TNF signaling renders EGFRwt-expressing NSCLC cell lines and an EGFRwt patient-derived xenograft (PDX) model highly sensitive to EGFR inhibition. In EGFR-mutant oncogene-addicted cells, blocking TNF enhances the effectiveness of EGFR inhibition. EGFR plus TNF inhibition is also effective in NSCLC with acquired resistance to EGFR inhibition. We suggest concomitant EGFR and TNF inhibition as a potentially new treatment approach that could be beneficial for a majority of lung cancer patients.