Roniciclib

Roniciclib is an orally bioavailable pan-cyclin dependent kinase (CDK) inhibitor, with IC₅₀s of 5-25 nM for CDK1, CDK2, CDK3, CDK4, CDK7 and CDK9. IC50 & Target:IC50: 5-25 nM (CDK)^[1]. In Vitro: Roniciclib (BAY 1000394) inhibits the kinase activity of the cell-cycle CDKs CDK1/cyclin B, CDK2/cyclin E, and CDK4/cyclinDwith IC₅₀ values of 7, 9, and 11 nM, respectively. The transcriptional CDKs CDK9/cyclin T1 and CDK7/cyclin H/MAT1 are inhibited in a similar range (5 and 25 nM)^[1].
Roniciclib potently inhibits the proliferation of various human and murine tumor cell lines with a very balanced profile (mean IC₅₀ on human tumor cells: 16 nM)^[2]. In Vivo: Tumor growth is strongly inhibited in a dose-dependent manner with T/C values of 0.19 at the lower dose and of 0.02 (tumor regression) at the higher dose. Furthermore, Roniciclib strongly inhibits growth of HeLa-MaTu tumors that have been grown to a size of approximately 50mm² before start of treatment (day 8 after inoculation). Treatment with Roniciclib at doses of 1.5 and 1 mg/kg slow tumor growth to T/C values of 0.15 and 0.62, respectively. Addition of Roniciclib to cisplatin result in a strong tumor growth inhibition with T/C values of 0.01 (1.0 mg/kg Roniciclib) and -0.02 (1.5 mg/kg Roniciclib)^[1].
Roniciclib has low blood clearance rates in mouse, rat, and dog (0.51, 0.78, and 0.50 Lh^-1kg^-1, respectively) ^[2].