Abstract
This is a report of biomarker analysis for sunvozertinib, a leading epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) targeting EGFR exon 20 insertion mutation (exon20ins) non-small cell lung cancer (NSCLC). There is a positive correlation between positive EGFR exon20ins in plasma circulating tumor DNA (ctDNA) and advanced disease. Shorter progression-free survival and lower objective response rate (45.8% vs. 68.0%) were observed in patients with positive EGFR exon20ins compared to those with negative status. Droplet digital PCR analysis showed that the EGFR exon20ins allele in ctDNA decreased over time in 85.7% of patients, with the earliest clearance occurred after 1 week of sunvozertinib treatment. Acquired EGFR C797S is identified as a potential on-target resistance mutation to sunvozertinib. Finally, efforts are undertaken to investigate therapeutic approaches that aim to overcome the putative acquired resistance to sunvozertinib.