Combining Radiotherapy and Immunotherapy in Patients with Extensive Stage Small Cell Lung Cancer (NRG-LU007, “the RAPTOR Trial”)

November 11, 2021

NRG-LU007: Randomized Phase II/III Trial of Consolidation Radiation + Immunotherapy for ES-SCLC: RAPTOR Trial

Discovery of major therapeutic advancements for the treatment of small cell lung cancer (SCLC) has been stagnant over the past few decades, and there is a need to improve clinical outcomes for this difficult disease. The current first-line treatment for extensive stage SCLC (ES-SCLC) includes 4 cycles of carboplatin and etoposide chemotherapy followed by maintenance atezolizumab, but this standard of care tends not to eliminate gross disease. NRG-LU007 (the RAPTOR Trial) was designed to address the theory that adding radiotherapy (RT) to immunotherapy and platinum-containing chemotherapy could further improve survival outcomes for patients with ES-SCLC resulting from the interactions between the RT and immunotherapy.

“It is hypothesized that combining consolidative radiotherapy with immunotherapy has the potential to improve local and systemic control for patients with ES-SCLC. Our goal is to demonstrate that adding local radiotherapy will enhance antitumor immunity and improve outcomes for these patients” stated Dr. Quynh-Nhu Nguyen, MD, of MD Anderson Cancer Center and the Principal Investigator of the RAPTOR trial.

The RAPTOR trial is actively accruing patients with ES-SCLC who have stable disease or partial response following initial systemic treatment. Participants on the trial are stratified by the number of sites that will be receiving RT, tumor response following initial chemotherapy, and ECOG performance status. Following stratification, patients are randomly assigned to receive either atezolizumab maintenance or consolidative RT to up to 5 sites at doses of either 20 Gy, 30 Gy or 45 Gy, Radiation sites include thoracic and extra thoracic (liver, bone, CNS, etc) followed by maintenance atezolizumab.

The Phase II portion of the trial will assess whether the addition of radiation therapy to standard of care treatment improves progression-free survival for trial participants when compared to standard of care alone. The Phase III portion of the trial will compare overall survival rates between the treatment arms. Secondary objectives of the trial include assessing toxicities between treatment arms as well as the impact of adding RT on survival outcomes for patients with 1-3 visible tumors versus 3 or more visible tumors, and on patients receiving RT to all visible disease versus those who do not receive RT to all visible disease. There is also an exploratory objective to assess pre-treatment tumor burden and survival benefit.

Learn more about this trial on ClinicalTrials.gov

Protocol documents and materials are located on the CTSU website.