Real-world data with afatinib in Spanish patients with treatment-naïve non-small-cell lung cancer harboring exon 19 deletions in epidermal growth factor receptor (Del19 EGFR): Clinical experience of the Galician Lung Cancer Group

Background In clinical studies, first-line afatinib demonstrated efficacy in Del19-EGFR NSCLC. Materials and Methods This prospective, non-interventional study assessed efficacy and safety of first-line afatinib in patients with advanced/metastatic NSCLC with Del19-EGFR from Galicia (Spain), with a preplanned analysis by age (<70 vs >= 70 years). Results Median age of 46 patients enrolled was 69.5 years (range 37-87). The objective response rate (ORR) was 78.2%, with median progression-free survival (PFS) of 20.5 months (95% CI 12.7, 28.3) and median overall survival (OS) of 37.5 months (95% CI 19.2-55.8). Outcomes by age (<70 vs >= 70 years) were ORR of 82.6% vs 73.9%, median PFS of 20.2 months (95% CI 14.8-25.6) vs 24.1 (9.8-38.3), and median OS of 45.1 months (95% CI, 17.0-73.1) vs 33.9 (28.7-39.1), respectively. Median treatment duration was 17.2 months (range 0.4-64.1) with 11 patients still on treatment; 14 patients received osimertinib at discontinuation due to T790M. Grade 3 adverse events included mucositis (n = 7, 15.2%), skin toxicity (n = 9, 19.6%), and diarrhea (n = 6, 13.0%) that were manageable with dose reductions. The afatinib dose was reduced in 31 patients (67.4%) and treatment was discontinued in 8 patients (17.4%) due to adverse events. By age (<70 vs >= 70 years), afatinib was dose-reduced in 13 (56.5%) vs 18 patients (78.3%) and discontinued in 3 (13.0%) vs 5 patients (21.7%), respectively. Conclusions PFS in our patients was longer than reported in clinical studies with similar response rates and toxicity, even in older patients, reflecting a good risk-benefit from afatinib in patients with Del19-EGFR NSCLC. Microabstract This real-world study of first-line afatinib in Caucasian patients with Del19 EGFR NSCLC reported durable efficacy and showed that older patients (> 70 years) benefitted from afatinib as much as younger patients. The safety profile of afatinib was as expected, albeit more dose reductions in older patients. Afatinib may be an option for patients with Del19 EGFR NSCLC, even in those who are older.