A real-world cohort study of first-line afatinib in patients with EGFR-mutant advanced non-small cell lung cancer in Vietnam

• Published in: BMC cancer 2024-02, Vol.24 (1), p.176-176, Article 176
• Main Authors: Pham, Cam Phuong, Nguyen, Thi Thai Hoa, Do, Anh Tu, Nguyen, Tuan Khoi, Hoang, Thi Anh Thu, Le, Tuan Anh, Vuong, Dinh Thy Hao, Nguyen, Dac Nhan Tam, Dang, Van Khiem, Nguyen, Thi Oanh, Pham, Van Luan, Nguyen, Minh Hai, Vo, Thi Huyen Trang, Do, Hung Kien, Vu, Ha Thanh, Nguyen, Thi Thuy Hang, Pham, Van Thai, Trinh, Le Huy, Nguyen, Khac Dung, Nguyen, Hoang Gia, Truong, Cong Minh, Pham, Tran Minh Chau, Nguyen, Thi Bich Phuong
• Format: Article
• Language: English
• Subjects: Advanced non-small cell lung cancer; Afatinib; Brain Neoplasms - drug therapy; Cancer therapies; Carcinoma, Non-Small-Cell Lung - drug therapy; Carcinoma, Non-Small-Cell Lung - genetics; Carcinoma, Non-Small-Cell Lung - pathology; Care and treatment; Cohort Studies; Diagnosis; Diarrhea; Drug dosages; EGFR mutations; Epidermal growth factor receptors; ErbB Receptors - genetics; ErbB Receptors - therapeutic use; First-line; Gene deletion; Gene mutations; Genetic aspects; Health aspects; Hospitals; Humans; Kinases; Lung cancer; Lung cancer, Non-small cell; Lung Neoplasms - drug therapy; Lung Neoplasms - genetics; Lung Neoplasms - pathology; Medical records; Metastases; Metastasis; Mutants; Mutation; Non-small cell lung carcinoma; Oncology; Patients; Protein Kinase Inhibitors - adverse effects; Radiation therapy; Radiosurgery; Response rates; Retrospective Studies; Small cell lung carcinoma; Stomatitis; Tumors; Vietnam; Vietnam - epidemiology
• ISSN: 1471-2407; 1471-2407
• DOI: 10.1186/s12885-024-11891-w

This study aimed to evaluate the efficacy and side effects of first-line afatinib treatment in a real-world setting in Vietnam. This retrospective study was conducted across nine hospitals in Vietnam. Advanced epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) patients who received afatinib as first-line therapy between April 2018 and June 2022 were included, and patient medical records were reviewed. Key outcomes were overall response rate (ORR), time-to-treatment failure (TTF), and tolerability. A total of 343 patients on first-line afatinib were eligible for the study. EGFR exon 19 deletion (Del19) alone was detected in 46.9% of patients, L858R mutation alone in 26.3%, and other uncommon EGFR mutations, including compound mutations, in 26.8%. Patients with brain metastases at baseline were 25.4%. Patients who received 40 mg, 30 mg, and 20 mg as starting doses of afatinib were 58.6%, 39.9%, and 1.5%, respectively. The ORR was 78.1% in the overall population, 82.6% in the Del19 mutation subgroup, 73.3% in the L858R mutation subgroup, and 75.0% in the uncommon mutation subgroup (p > 0.05). The univariate and multivariate analyses indicate that the ORR increased when the starting dose was 40 mg compared to starting doses below 40 mg (83.9% vs. 74.3%, p = 0.034). The median TTF (mTTF) was 16.7 months (CI 95%: 14.8-18.5) in all patients, with a median follow-up time of 26.2 months. The mTTF was longer in patients in the common EGFR mutation subgroup (Del19/L858R) than in those in the uncommon mutation subgroup (17.5 vs. 13.8 months, p = 0.045) and in those without versus with brain metastases at baseline (17.5 vs. 15.1 months, p = 0.049). There were no significant differences in the mTTF between subgroups based on the starting dose of 40 mg and  0.05). The most common treatment-related adverse events (any grade/grade ≥ 3) were diarrhea (55.4%/3.5%), rash (51.9%/3.2%), paronychia (35.3%/5.0%), and stomatitis (22.2%/1.2%). Afatinib demonstrated clinical effectiveness and good tolerability in Vietnamese EGFR-mutant NSCLC patients. In our real-world setting, administering a starting dose below 40 mg might result in a reduction in ORR; however, it might not have a significant impact on TTF.