ARN-21934 is a potent, highly selective, blood-brain barrier (BBB) penetrant inhibitor for human topoisomerase II α over β. ARN-21934 inhibits DNA relaxation with an IC50 of 2 μM as compared to the anticancer agent Etoposide (IC50=120 μM). ARN-21934 exhibits a favorable in vivo pharmacokinetic profile and is a promising lead compound for anticancer research[1].

ARN-21934 display a different affinity for topoIIα and topoIIβ. ARN-21934 is more potent against the α isoform, the IC50 value for the inhibition of DNA relaxation by topoIIα is 2 μM, the value for inhibition of DNA relaxation by topoIIβ is 120 μM[1].ARN-21934 exhibits a small panel of human cancer cell lines. It against melanoma (A375 and G-361), breast (MCF7), endometrial (HeLa), lung (A549), and androgen-independent prostate (DU145) cancer cells with IC50 values of 12.6 μM, 8.1 μM, 15.8 μM, 38.2 μM, 17.1 μM, and 11.5 μM, respectively[1].

ARN-21934 (intraperitoneal injection; 10 mg/kg; single dose) reaches a maximal plasma concentration of 0.68 μg/mL after 15 min. The half-life is 149 min in circulation, still being present in plasma 360 min after injection. The compound also exhibits good clearance values (0.116 L/(min kg)). Besides, ARN-21934 is able to reach the brain, with a maximum concentration of compound at 60 min, and is still present in the brain 360 min after injection[1]

[1]. Jose Antonio Ortega, et al. Novel, Potent, and Druglike Tetrahydroquinazoline Inhibitor That Is Highly Selective for Human Topoisomerase II α over β. J Med Chem. 2020 Nov 12;63(21):12873-12886.