Efficacy of ramucirumab combined with erlotinib or osimertinib in untreated EGFR-mutated NSCLC patients with asymptomatic brain metastases: insights from molecular biomarkers in the RELAY-brain trial.

Abstract

Background: The RELAY-Brain trial examined the clinical utility and survival impacts of ramucirumab (RAM) combined with epidermal growth factor receptor (EGFR)-TKI in patients with EGFR-mutated non-small-cell lung cancer (NSCLC) with brain metastases. Although RAM combined with erlotinib (ERL) is known to have clinical benefits, the benefits in patients with baseline brain metastases remain unclear. This report examined the long-term follow-up data (Japan Registry of Clinical Trials: jRCTs2051190027) of the same patients, analyzing relevant biomarkers from tumor and plasma samples.

Patients and methods: The six patients enrolled in the RELAY-Brain trial received RAM plus ERL or osimertinib (OSM). Our long-term follow-up observational study assessed patient survival, treatment status, and genetic biomarkers. Tumor and plasma samples were analyzed at baseline, during treatment, and at disease progression using next-generation sequencing and droplet digital PCR, to identify gene alterations and EGFR-TKI-resistant mutations.

Results: After median follow-up of 44.2 months, the first site of disease progression in three of the patients was the brain metastases. In the RAM + ERL group, two patients with the T790M mutation subsequently received OSM. Progression-free survival (PFS) and overall survival ranged from 10.46 to 42.07 months and from 30.14 to 52.25 months, respectively. Gene alterations included TP53 mutations in three patients and ERBB2 and PIK3CA mutations in two. TP53 mutations were associated with shorter PFS.

Conclusion: RAM with ERL or OSM achieved significant clinical benefits for patients with EGFR-mutated NSCLC with asymptomatic brain metastases. These positive outcomes and the identification of related biomarkers support the therapeutic potential of these combinations.