Data Sheet 1_Comparative profiling of osimertinib and fourth-generation EGFR inhibitors on EGFR-mutant proteins and cell lines.pdf

BLU-945 was the only inhibitor demonstrating broad activity across activating EGFR variants with or without the T790M and/or C797S resistance mutation. JBJ-09-063 selectively inhibited L858R-driven mutants and maintained similar potency across ATP conditions, which is consistent with an allosteric, ATP-independent mechanism. Silevertinib showed high potency against activating EGFR mutants with or without the C797S mutation but markedly reduced activity in the presence of the T790M mutation.

All fourth-generation inhibitors retained binding to C797S mutants in surface plasmon resonance experiments. Moreover, JBJ-09-063 bound EGFR L858R + T790M even after osimertinib saturation, confirming their non-overlapping binding sites. In the engineered NCI-H1975 L858R + T790M + C797S cell line model, JBJ-09-063 showed the highest potency among the tested inhibitors.

In contrast, silevertinib demonstrated the greatest mutant-selective activity across a broad cell-line panel, with >200-fold selectivity for EGFR-mutant over EGFR wild-type cells, outperforming osimertinib in this regard.</p>Conclusion<p>This comparative analysis highlights the substantial differences in the activity landscapes of fourth-generation EGFR inhibitors. The gathered insights can provide direction for the optimal deployment of the inhibitors in distinct clinical contexts.</p>