Treatment outcomes and safety of afatinib in advanced squamous cell lung cancer progressed after platinum‐based doublet chemotherapy and immunotherapy (SPACE study)

Afatinib is an ErbB family blocker approved for the treatment of epidermal growth factor receptor mutation‐positive nonsmall‐cell lung cancer. A pivotal trial demonstrated significant clinical benefits with manageable toxicity of afatinib as a second‐line treatment option in squamous cell carcinoma of the lung (SCC) which led to approval in >60 countries. However, these results were derived from a controlled study conducted in selected patients and are not necessarily representative of the real‐world use of this drug. In addition, data on afatinib use after immunotherapy in this clinical setting are lacking. The aim of this study is to evaluate the treatment outcomes and safety of afatinib as a second‐ or later‐line treatment for SCC and to identify potential predictive biomarkers. As a real‐world observational study, 130 eligible patients with advanced SCC, who progressed after platinum‐based chemo‐ and immunotherapy, will be enrolled. Treatment outcomes and safety data will be collected for both the retrospective and prospective cohorts, and molecular profiling using tissue and plasma will be performed for the prospective cohort. The primary endpoint is time to treatment failure, and the secondary endpoints are objective response rate, progression‐free survival, overall survival, and safety. Comparison of clinical outcomes with respect to the different programmed death‐ligand 1 expression and molecular characteristics will also be carried out. This study will provide additional evidence on the usefulness of afatinib as a subsequent treatment, as well as feasible molecular biomarkers to predict its efficacy in this clinical setting.