Journal Article

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

Nguyen, Dac Nhan Tam, Truong, Cong Minh, Nguyen, Hoang Gia, Nguyen, Tuan Khoi, Vuong, Dinh Thy Hao, Nguyen, Thi Thuy Hang, Vu, Ha Thanh, Nguyen, Thi Bich Phuong, Pham, Van Luan, Le, Tuan Anh, Dang, Van Khiem, Do, Hung Kien, Trinh, Le Huy, Nguyen, Minh Hai, Nguyen, Thi Thai Hoa, Hoang, Thi Anh Thu, Nguyen, Khac Dung, Do, Anh Tu, Pham, Cam Phuong, Pham, Van Thai, Pham, Tran Minh Chau, Nguyen, Thi Oanh, Vo, Thi Huyen Trang

2024

Overview

Background This study aimed to evaluate the efficacy and side effects of first-line afatinib treatment in a real-world setting in Vietnam. Methods 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. Results 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 < 40 mg (16.7 vs. 16.9 months, p  > 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%). Conclusions 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.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Advanced non-small cell lung cancer / Afatinib / Analysis / Biomedical and Life Sciences / Biomedicine / Brain cancer / Brain Neoplasms - drug therapy / Cancer control in low- and middle-income countries / Cancer Research / 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 / Complications and side effects / Diagnosis / Diarrhea / Drug dosages / EGFR mutations / Epidermal growth factor / Epidermal growth factor receptors / ErbB Receptors - genetics / ErbB Receptors - therapeutic use / First-line / Gene deletion / Gene mutations / Genetic aspects / Health aspects / Health Promotion and Disease Prevention / Hospitals / Humans / Kinases / Lung cancer / Lung cancer, Non-small cell / Lung cancer, Small cell / Lung Neoplasms - drug therapy / Lung Neoplasms - genetics / Lung Neoplasms - pathology / Medical records / Medicine/Public Health / 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 / Surgical Oncology / Tumors / Vietnam / Vietnam - epidemiology