This phase II/III trial compares the effect of adding radiation therapy to the usual maintenance therapy with atezolizumab versus atezolizumab alone in patients who have already received atezolizumab plus chemotherapy for the treatment of small cell lung cancer that has spread outside of the lung or to other parts of the body (extensive stage). Immunotherapy with monoclonal antibodies, such as atezolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Radiation therapy uses high energy x-rays to kill tumor cells and shrink tumors. Giving radiation therapy in addition to atezolizumab may extend the time without extensive small cell lung cancer growing or spreading compared to atezolizumab alone.
Any confirmation (cytologic, histologic, or pathologic) of extensive stage small cell lung cancer at any site, either primary or metastases
Partial response (PR) or stable disease (SD) after 4-6 cycles of etoposide/platinum (E/P) doublet plus atezolizumab by re-staging scans (positron emission tomography [PET]/computed tomography [CT] scan, diagnostic CT scan, magnetic resonance imaging [MRI] optional per treating physician); atezolizumab should continue through randomization. Patients must be randomized within 9 weeks of last dose of etoposide/platinum (if not receiving PCI) or 6 weeks from completion of prophylactic cranial irradiation (PCI)
NOTE: Patients must have at least 3 cycles of E/P plus atezolizumab. They can have one cycle of induction E/P without concurrent atezolizumab if unable to receive concurrent E/P combined with atezolizumab for all cycles of induction therapy
Patients must have measurable disease (per Response Evaluation Criteria in Solid Tumors [RECIST]) and 3 or fewer observable liver metastases and no evidence of progressive disease (per RECIST) at time of enrollment
Metastatic disease invading the liver (> 3 metastases), heart or > 10 metastatic sites detectable after induction systemic therapy. Each visible bone metastasis on radiographic scan counts as one site
Patients with a concurrent malignancy whose natural history or treatment has the potential to interfere with the safety or efficacy assessment of the investigational regimen with atezolizumab or radiation
Prior radiotherapy in the thorax that would result in overlapping RT fields, unless the overlapping fields meet acceptable dose constraints for normal tissue
Active autoimmune disease, including, but not limited to: systemic lupus erythematosus; rheumatoid arthritis; inflammatory bowel disease (e.g. Crohn's, ulcerative colitis); vascular thrombosis associated with antiphospholipid syndrome; Wegener's granulomatosis; Sjogren's syndrome; Guillain-Barre syndrome; multiple sclerosis; vasculitis; or glomerulonephritis.
National Cancer Institute (NCI)
Lead sponsor
NRG Oncology
Collaborator