Zeteletinib (BOS-172738; DS-5010) is an orally active, selective RET kinase inhibitor with nanomolar potency against RET and >300-fold selectivity against VEGFR2. Zeteletinib shows exquisite potency for the wild type RET, RETV804M/L gatekeeper mutants, and the most common oncogenic RET mutation M918T. Zeteletinib has potent antitumor activity[1][2][3].
In biochemical assays of 106 kinases, RET and platelet-derived growth factor receptor (PDGFR) alpha/beta were inhibited more than 80% by 193 nM Zeteletinib (BOS-172738; DS-5010). The IC50 values of Zeteletinib against RET, RET-GKm (V804L) were single digit nano-molar even under a condition of high concentration of ATP; besides it against KDR was more than 1000 nM[1].
In a Ba/F3-RET subcutaneous tumor model, Zeteletinib (BOS-172738; DS-5010) dosing at 10 mg/kg twice daily (bid) induces tumor regression[1]. In an LC2/ad NSCLC xenograft model, which has the RET-CCDC6 fusion gene, Zeteletinib dosing at 1 mg/kg thrice daily (tid) induced tumor regression[1].
[1]. Yasuyuki Kaneta, et al.Abstract B173: Preclinical characterization and antitumor efficacy of DS-5010, a highly potent and selective RET inhibitor. MOLECULAR CANCERTHERAPEUTICS. January 2018, Volume 17, Issue 1.
[2]. Patrick Schoffski, et al. BOS172738, a highly potent and selective RET inhibitor, for the treatment of RET-altered tumors including RET-fusion+ NSCLC and RET-mutant MTC: Phase 1 study results. Journal of Clinical Oncology 39, no. 15_suppl (May 20, 2021) 3008-3008.
[3]. Kyaw Z Thein, et al. Precision therapy for RET-altered cancers with RET inhibitors. Trends Cancer. 2021 Dec;7(12):1074-1088.