2023 World Conference on Lung Cancer (Posters)-P1.23. ctDNA Positivity Is a Clinical Prognosis Biomarker in Patients with EGFR ex20ins+ NSCLC

P1.23. ctDNA Positivity Is a Clinical Prognosis Biomarker in Patients with EGFR ex20ins+ NSCLC - PDF(Slides)

Pdf Summary

This study aimed to evaluate the impact of EGFR exon 20 insertion (ex20ins) circulating tumor DNA (ctDNA) on progression-free survival (PFS) in patients with EGFR ex20ins non-small-cell lung cancer (NSCLC) treated with mobocertinib after prior platinum-based chemotherapy. Plasma samples were collected from patients at baseline and on Cycle 3, Day 1 (C3D1) of mobocertinib treatment, and ctDNA was analyzed using next-generation sequencing assays. The association between ctDNA changes and PFS was assessed.<br /><br />The results showed a significant association between the presence of EGFR ex20ins ctDNA at baseline and PFS. Patients with no detectable ctDNA had longer median PFS compared to those with detectable ctDNA (14.69 vs 5.52 months). Additionally, patients who had an increase in EGFR ex20ins ctDNA by C3D1 had a higher risk of disease progression than those who had a decrease in ctDNA. The patients with an increase in ctDNA had a shorter mean PFS compared to those who remained negative for ctDNA from baseline to C3D1.<br /><br />Therefore, it was concluded that baseline ctDNA positivity is a prognostic marker for PFS in patients with EGFR ex20ins NSCLC treated with mobocertinib. The clearance of ctDNA at C3D1 was associated with longer PFS. These findings highlight the potential of ctDNA as a biomarker for predicting treatment response and outcomes in this patient population. Further evaluation of EGFR ex20ins ctDNA as a prognostic biomarker in NSCLC is warranted.<br /><br />Mobocertinib is an oral EGFR tyrosine kinase inhibitor approved for the treatment of EGFR ex20ins locally advanced or metastatic NSCLC. The study was based on data from a phase 1/2 trial, and the results provide important insights into the use of ctDNA as a clinical prognostic marker in this patient population.

Asset Subtitle

Sampurna Chatterjee

Meta Tag

Speaker Sampurna Chatterjee

Topic Pathology & Biomarkers: Liquid Based Biomarkers

Keywords

EGFR exon 20 insertion

ex20ins

circulating tumor DNA

ctDNA

progression-free survival

PFS

non-small-cell lung cancer

NSCLC

mobocertinib

platinum-based chemotherapy