Central Nervous System Efficacy of Furmonertinib (AST2818) Versus Gefitinib as First-Line Treatment for EGFR-Mutated NSCLC: Results From the FURLONG Study

Furmonertinib (AST2818) is a pan-EGFR tyrosine kinase inhibitor with central nervous system (CNS) antitumor activity. We report the CNS efficacy of furmonertinib compared with gefitinib in untreated EGFR-sensitizing mutation-positive NSCLC from the FURLONG study.FURLONG was a randomized, double-blind, phase 3 study conducted in 55 hospitals in the People's Republic of China. Patients 1:1 randomly received furmonertinib 80 mg once daily or gefitinib 250 mg once daily treatment. At screening, all the patients underwent brain imaging examination. Patients with asymptomatic steady CNS metastases at baseline constituted this preplanned CNS subgroup analysis.A total of 358 patients were enrolled in the FURLONG study. In the 133 (37%) patients who had measurable or nonmeasurable CNS lesions, CNS progression-free survival was 20.8 months (95% confidence interval [CI]: 15.2-25.3) in the furmonertinib group and 9.8 months (95% CI: 7.2-18.0) in the gefitinib group (hazard ratio = 0.40 [95% CI: 0.23-0.71], p = 0.0011). In the 60 patients (17%) who had measurable CNS lesions, CNS objective response rate was 91% (95% CI: 72-99) with furmonertinib and 65% (95% CI: 48-80) with gefitinib (OR = 6.82 [95% CI: 1.23-37.67], p = 0.0277). The least-square mean of CNS depth of response was 62% (95% CI: 51-72) in the furmonertinib group and 39% (95% CI: 30-47) in the gefitinib group, the mean difference was 23% (95% CI: 10-37, p = 0.0011).Furmonertinib first-line treatment was found to have superior efficacy in CNS progression-free survival, CNS objective response rate, and CNS depth of response compared with gefitinib in patients with EGFR-mutated NSCLC with CNS metastases.