Real-world effectiveness of second-line Afatinib versus chemotherapy for the treatment of advanced lung squamous cell carcinoma in immunotherapy-naïve patients.

Background: Limited treatment options exist for relapsed advanced lung squamous cell carcinoma (SCC), leading to poor outcomes compared with adenocarcinoma. This study aimed to investigate the efficacy of second-line afatinib versus chemotherapy in patients with advanced lung SCC who progressed after first-line chemotherapy.

Methods: In this retrospective, multisite cohort study, we recruited patients with initial locally advanced or metastatic lung SCC from four institutes in Taiwan between June 2014 and October 2020. The primary endpoint of this study was progression-free survival (PFS), and the secondary endpoints were the objective response rate (ORR), disease control rate (DCR), and overall survival (OS).

Results: The present study enrolled 108 patients: 19 received second-line afatinib, and 89 received second-line chemotherapy. The median ages were 71 and 67 years, respectively. PFS was significantly longer among patients who received afatinib than among those who received chemotherapy (median 4.7 months [95% confidence interval (CI), 0.1-7.5] vs. 2.6 months [95% CI, 0.9-6.7]; hazard ratio (HR) 0.53 [95% CI 0.32-0.88], p = 0.013). Compared with the chemotherapy group, OS was longer in the afatinib group but did not reach significance (median 16.0 months [95% CI, 6.1-22.0] vs. 12.3 months [6.2-33.9]; HR 0.65 [95% CI 0.38-1.11], p = 0.112).

Conclusions: Afatinib offered a longer PFS and comparable OS to chemotherapy in advanced lung SCC patients in a real-world setting, it may be considered as a 2nd line alternative treatment choice for immunotherapy unfit advanced lung SCC patients.