Abstract 511: Neratinib monotherapy in advanced non-small cell lung cancer with EGFR exon 18 mutations in China

Abstract Background: In NSCLC patients, EGFR exon 18 mutations account for approximately 3-5% and are associated with a poor prognosis. In phase 2 SUMMIT global trial, 29 metastatic NSCLC patients with EGFR exon 18 mutations received neratinib monotherapy, having good result. The objective response rate (ORR) was 35%. However, only 1 (4.5%) Asian individual is enrolled in study. Therefore, there is an urgent need to explore the effect of neratinib monotherapy in Chinese NSCLC patients with EGFR exon 18 mutation. Methods: Planned 14 patients with EGFR exon 18-mutated NSCLC who had failed first-line standard chemotherapy were enrolled in this study(NCT06029816). The primary endpoint is the ORR by the investigator according to RECISTv1.1 and the secondary endpoints are DCR (Disease Control Rate), PFS (Progression-Free Survival). Results: To date, 7 advanced NSCLC patients with exon 18 mutations after receiving Neratinib treatment following the failure of standard first-line therapy. The ORR is 42.9% (3 PR, 4 SD) and DCR is 100.0%. The common 1-2 grade treatment-related adverse events (AEs) occur in 82% of patients. 28.6% of patients have Diarrhea (CTCAE Grade 2), and that can be managed after loperamide intervention within 3 days. To date, there have been no grade 4- 5 AEs in any of the patients. Conclusion: Neratinib monotherapy has demonstrated tolerable safety and encouraging preliminary efficacy in NSCLC with EGFR exon 18 mutations. This study is expected to provide more treatment options for Chinese patients with NSCLC who have EGFR exon 18 mutations. Citation Format: Wenfeng Fang, Ning Li, Runxiang Yang, Ying Cheng, Baogang Liu, Haiyong Wang, Lin Wu, Qiming Wang, Steve Shen. Neratinib monotherapy in advanced non-small cell lung cancer with EGFR exon 18 mutations in China [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 511.