TPX-0131 is a potent, selective, CNS-penetrant and orally active inhibitor of wild-type ALK ( IC 50 of 1.4 nM) and is potent against ALK-resistant mutation, e.g. G1202R ( IC 50 of 0.3 nM), L1196M ( IC 50 of 0.3 nM). TPX-0131 has strong antitumor activities [1].

TPX-0131 potently inhibits the resistance mutations of wild-type ALK (IC 50 = 1.4 nM) and 26 ALK. TPX-0131 inhibits C1156Y, E1210K/S1206C, L1198F/C1156Y, L1196M/L1198F, E1210K, L1196M, T1151M, deleted G1202, S1206R, G1202R/L1198F, F1174L, F1245C, R1275Q, and G1202R ALK mutations with IC50 values of <1 nM. TPX0131 has IC 50 values of 1-2 nM for the following ALK mutations: L1198F, L1152R, F1174S, T1151-L1152 insT, V1180L, G1269A, F1174C. TPX-0131 is less active against ALK mutations including I1171N, L1152P, D1203N, D1203N/E1210K, and G1269S, with IC 50 values of 2-7 nM [1]. TPX-0131 is a potent inhibitor of ALK autophosphorylation in Ba/F3 cells expressing EML4-ALK G1202R solvent front, EML4-ALK G1202R/L1196M, or EML4-ALK G1202R/L1198F mutations, with IC50 values of approximately 3-10 nM [1].

TPX-0131 administered orally at doses of 2 mg/kg, 5 mg/kg, and 10 mg/kg twice daily for two weeks to female SCID/beige mice (5-8 weeks old) bearing Ba/F3 cells demonstrated dose-dependent tumor growth inhibition (TGI) of 64%, 120%, and 200% (complete regression), respectively, in ALK mutation-dependent xenograft models [1].