Central Nervous System Outcomes of Lazertinib Versus Gefitinib in EGFR-Mutated Advanced NSCLC: A LASER301 Subset Analysis

Abstract

IntroductionLazertinib, a third-generation mutant-selective EGFR tyrosine kinase inhibitor, improved progression-free survival compared with gefitinib in the phase 3 LASER301 study (ClinicalTrials.gov Identifier: NCT04248829). Here, we report the efficacy of lazertinib and gefitinib in patients with baseline central nervous system (CNS) metastases. MethodsTreatment-naive patients with EGFR–mutated advanced NSCLC were randomized one-to-one to lazertinib (240 mg/d) or gefitinib (250 mg/d). Patients with asymptomatic or stable CNS metastases were included if any planned radiation, surgery, or steroids were completed more than 2 weeks before randomization. For patients with CNS metastases confirmed at screening or subsequently suspected, CNS imaging was performed every 6 weeks for 18 months, then every 12 weeks. End points assessed by blinded independent central review and Response Evaluation Criteria in Solid Tumors version 1.1 included intracranial progression-free survival, intracranial objective response rate, and intracranial duration of response. ResultsOf the 393 patients enrolled in LASER301, 86 (lazertinib, n = 45; gefitinib, n = 41) had measurable and or non-measurable baseline CNS metastases. The median intracranial progression-free survival in the lazertinib group was 28.2 months (95% confidence interval [CI]: 14.8–28.2) versus 8.4 months (95% CI: 6.7–not reached [NR]) in the gefitinib group (hazard ratio = 0.42, 95% CI: 0.20–0.89, p = 0.02). Among patients with measurable CNS lesions, the intracranial objective response rate was numerically higher with lazertinib (94%; n = 17) versus gefitinib (73%; n = 11, p = 0.124). The median intracranial duration of response with lazertinib was NR (8.3–NR) versus 6.3 months (2.8–NR) with gefitinib. Tolerability was similar to the overall LASER301 population. ConclusionsIn patients with CNS metastases, lazertinib significantly improved intracranial progression-free survival compared with gefitinib, with more durable responses.