Bridge Biotherapeutics announced promising interim clinical data from its Phase I study of BBT-176, a fourth-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI). The data, presented at the International Association for the Study of Lung Cancer 2022 World Conference on Lung Cancer (IASLC WCLC 2022), show promising early evidence of efficacy and favorable tolerability in patients with non-small cell lung cancer (NSCLC). The oral presentation delivered by Sun Min Lim, M.D., Ph.D., assistant professor at Yonsei University College of Medicine, discussed the correlation between molecular response and radiologic response in patient participants in the study.

One patient with advanced NSCLC showing C797S triple mutations, confirmed as one of the partial response (PR) cases, showed up to 53 percent decrease of EGFR mutant allele frequency compared to the baseline. Data from the five patients who had been treated with BBT-176 over 100 days suggested that circulating tumor DNA (ctDNA) analysis enabled with liquid biopsy may be useful not only in identifying those most likely to benefit from fourth-generation EGFR TKI treatments such BBT-176, but also monitoring therapeutic response with treatment of a fourth-generation EGFR TKI. The study also confirmed the preliminary efficacy of BBT-176 in treating advanced NSCLC patients harboring an EGFR mutation who had previously been treated with at least one EGFR TKI.

Adverse events were primarily low grade, with GI toxicities and skin rash being most common, necessitating dose modifications in some patients. The pharmacokinetic profile of BBT-176 was shown to be dose-proportional in the study.