Efficacy and safety of limertinib versus gefitinib as first-line treatment for locally advanced or metastatic non-small-cell lung cancer with EGFR-sensitising mutation: a randomised, double-blind, double-dummy, phase 3 trial

Abstract

Background: Limertinib is a new third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor. This study aimed to prospectively assess the efficacy and safety of limertinib versus gefitinib as a first-line treatment for locally advanced or metastatic non-small-cell lung cancer (NSCLC) with EGFR-sensitising mutation.

Methods: This multicentre, randomised, double-blind, double-dummy, phase 3 trial was done at 56 hospitals in China. Eligible patients were aged ≥18 years with locally advanced or metastatic NSCLC with EGFR-sensitising mutation (exon 19 deletion or exon 21 L858R mutation) detected in tumour tissue samples using the Cobas EGFR Mutation Test at a central laboratory. Patients were randomly assigned (1:1) to receive oral limertinib 80 mg twice a day and gefitinib-matching placebo 250 mg once a day or oral gefitinib 250 mg once a day plus limertinib-matching placebo 80 mg twice a day in 21-day cycles, until disease progression or other discontinuation criteria was met. Random assignment was stratified according to EGFR mutation type (exon 19 deletion or exon 21 L858R mutation) and CNS metastasis (yes or no) using permuted blocks (block size four) through an interactive web-based response system. The primary endpoint was independent central review (ICR)-assessed progression-free survival. All enrolled patients who received at least one dose of study treatment were included in the full analysis set for efficacy analysis. All enrolled patients who received at least one dose of study treatment and one safety assessment were included in the safety set. This study is registered with ClinicalTrials.gov, NCT04143607, and follow-up is ongoing.

Findings: Between June 30, 2021, and Sept 22, 2022, 337 patients were enrolled and 168 were randomly assigned to the limertinib group and 169 to the gefitinib group. Patients' median age was 63 years (34-82). 214 (64%) of 337 patients were female and 123 (36%) were male. The median masked ICR-assessed progression-free survival was 20·7 months (95% CI 15·2-22·1) in the limertinib group and 9·7 months (95% CI 8·3-11·1) in the gefitinib group (hazard ratio [HR] 0·44 [95% CI 0·34-0·58]; p<0·0001). Treatment-related adverse events of grade 3 or worse occurred in 42 (25%) of 168 patients in the limertinib group and 42 (25%) of 169 patients in the gefitinib group. Treatment-related serious adverse events occurred in nine (5%) patients and 17 (10%) patients in each group, respectively. Six (4%) patients in the limertinib group died due to adverse events, all of which were considered possibly unrelated to the study drug by investigators. In the gefitinib group, seven (4%) patients died due to adverse events, with three (2%) of those deaths judged as possibly related to the study drug by investigators. Three treatment-related deaths in the gefitinib group were recorded (one case related to pneumonia and two with cause of death unknown).

Interpretation: Limertinib showed superior efficacy compared with gefitinib and a manageable safety profile for locally advanced or metastatic NSCLC patients with EGFR-sensitising mutation and should be considered as another first-line treatment option for this patient population.

Funding: Jiangsu Aosaikang Pharmaceutical.

Translation: For the Chinese translation of the abstract see Supplementary Materials section.