Prospective Observational Real-World Study of Afatinib as First-Line Treatment in Patients with Epidermal Growth Factor Receptor (EGFR) Mutation-Positive Advanced Non-Small Cell Lung Cancer (NSCLC) in China

Purpose: Approximately 38% of Chinese patients with non-small cell lung cancer (NSCLC) exhibit a mutation in the epidermal growth factor receptor (EGFR) gene. Afatinib, which targets the EGFR, is approved for first-line treatment in advanced EGFR mutation-positive NSCLC worldwide. The aim of this prospective, observational and non-interventional real-world study was to examine the effectiveness and safety of first line afatinib in Chinese patients, newly diagnosed with EGFR mutation-positive NSCLC. Patients and Methods: Patients were enrolled at 10 sites in China from May 2020 to December 2021 and followed-up from May 2020 to December 2023. Adult patients (aged ≥ 18 years) were treated with oral afatinib 30 mg or 40 mg once daily. The primary outcome was time on treatment (TOT). Secondary outcomes were overall survival (OS), overall response rate (ORR) and safety. Results: A total of 72 patients were enrolled and treated with afatinib. Most were male (54.2%), Chinese (98.6%), never smokers (63.9%), and had an Eastern Cooperative Oncology Group (ECOG) performance status score of 0– 1 (98.6%) and patients had a mean (SD) age of 62.2 (9.6) years. Median TOT overall was 14.4 months and was prolonged in younger (aged < 65 years) vs older (aged ≥ 65 years) age groups, common vs uncommon baseline EGFR mutations, and higher afatinib starting dose (40 mg vs 30 mg). Median OS was not reached; the median follow-up time of the study was 25.1 months. ORR was 62.7% overall and was higher in common vs uncommon baseline EGFR mutations, higher afatinib starting dose, and with vs without brain metastases. The two most common treatment-emergent adverse events were diarrhea and rash. No new safety concerns were found. Conclusion: This study provides real-world evidence of the effectiveness and safety of afatinib as first-line therapy for Chinese patients with EGFR mutation-positive advanced NSCLC. Keywords: NSCLC, EGFR mutation-positive, afatinib, real-world evidence