Targeting C797S mutations and beyond in non-small cell lung cancer-a mini-review

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Non-small cell lung cancer (NSCLC) has high mortality, with common epidermal growth-factor receptor (EGFR) mutations treatable by targeted therapies.
• Uncommon EGFR mutations and acquired resistance (e.g., C797S) to existing therapies limit treatment efficacy.
• Resistance mechanisms include drug-tolerant persister cells, chromosomal instability, and extrachromosomal extracellular DNA (ecDNA).

Purpose of the Study:

• To evaluate the efficacy of fourth-generation EGFR inhibitors against common and uncommon EGFR mutations in NSCLC.
• To investigate the potential of BDTX-1535 in overcoming resistance mechanisms, including the C797S mutation.
• To explore novel therapeutic strategies for NSCLC patients with acquired resistance to EGFR-tyrosine kinase inhibitors (TKIs).

Main Methods:

• Preclinical evaluation of BDTX-1535, an orally bioavailable, brain-penetrating, irreversible EGFR inhibitor.
• Testing BDTX-1535 against a panel of common and uncommon EGFR mutations, including resistance mutations like C797S and T790M.
• Assessment of BDTX-1535 activity in experimental models of NSCLC and glioblastoma.

Main Results:

• BDTX-1535 demonstrated significant antitumor activity in preclinical models.
• It inhibited common EGFR mutations and over 50 uncommon mutations, including T790M and C797S.
• BDTX-1535 showed potential to overcome osimertinib resistance and activity against extracellular domain mutations, though less effective against exon 20 insertions.

Conclusions:

• Fourth-generation EGFR inhibitors, such as BDTX-1535, represent a promising therapeutic advance for NSCLC.
• These novel agents can target various EGFR mutations and overcome key resistance mechanisms, including C797S.
• Further clinical investigation is warranted to establish the role of BDTX-1535 in managing NSCLC with complex resistance profiles.