Repotrectinib (TPX-0005) is a potent ROS1 (IC50=0.07 nM), TRK (0.83/0.05/0.1 nM=TRKA/B/C) inhibitor. Repotrectinib (TPX-0005) potently inhibits WT ALK (1.01 nM) and mutant ALKs including ALK G1202R (1.26 nM) and ALK L1196M (1.08 nM). It also inhibits a variety of other kinases, including JAK2, LYN, Src, and FAK (1.04, 1.66, 5.3, and 6.96 nM, respectively) [1][2].
Repotrectinib (TPX-0005) effectively overcomes this primary resistance (IC50 100 nM in cell proliferation assay) with strong inhibition of the phosphorylation of EML4-ALK (IC50 13 nM) and the SRC substrate paxillin (IC50 107 nM). Repotrectinib inhibits H2228 cell migration in a wound healing assay with similar activity to saracatinib[1].
Repotrectinib (TPX-0005) effectively inhibits tumor growth in vivo in ALK WT and ALK G1202R xenografts[1].
References:
[1]. Dayong Zhai, et al. Abstract 2132: The novel, rationally-designed, ALK/SRC inhibitor TPX-0005 overcomes multiple acquired resistance mechanisms to current ALK inhibitors. Cancer Research. July 2016
[2]. Karachaliou N, et al. Common Co-activation of AXL and CDCP1 in EGFR-mutation-positive Non-smallcell Lung Cancer Associated With Poor Prognosis. EBioMedicine. 2018 Mar;29:112-127.