Telatinib (mesylate)

Telatinib mesylate (Bay 57-9352 mesylate) is a potent and orally active VEGFR2, VEGFR3, PDGFα, and c-Kit inhibitor with IC₅₀s of 6 nM, 4 nM, 15 nM and 1 nM, respectively^[1]. In Vitro: Telatinib enhances the anticancer activity of ABCG2 substrate anticancer drugs by inhibiting ATP-binding cassette G2 (ABCG2) efflux transporter activity. Co-incubation of ABCG2-overexpressing drug resistant cell lines with Telatinib and ABCG2 substrate anticancer drugs significantly reduces cellular viability, whereas Telatinib alone does not significantly affect drug sensitive and drug resistant cell lines. Telatinib at 1 μM does not significantly alter the expression of ABCG2 in ABCG2-overexpressing cell lines. Telatinib at 1 μM significantly enhances the intracellular accumulation of [³H]-mitoxantrone (MX) in ABCG2-overexpressing cell lines^[2].
Telatinib at 1 μM significantly reduces the rate of [³H]-MX efflux from ABCG2-overexpressing cells. Furthermore, Telatinib significantly inhibits ABCG2-mediated transport of [³H]-E 17βG in ABCG2 overexpressing membrane vesicles^[2]. In Vivo: Telatinib (15 mg/kg; oral dministration; every 2nd and 3rd day; total 12 times; male athymic NCR (nu/nu) nude mice) with Doxorubicin (1.8 mg/kg) significantly decreases the growth rate and tumor size of ABCG2 overexpressing tumors in a xenograft nude mouse model^[2].