Nepicastat (SYN117; RS-25560-197) is a dopamine beta-hydroxylase inhibitor with IC50 of 8.5 ± 0.8 and 9.0 ± 0.8 nM for bovine and human, respectively. IC50 value: 8.5/9.0 nM(bovine/human dopamine beta-hydroxylase)Dopamine beta-hydroxylase is an enzyme that catalyzes the conversion of dopamine to norepinephrine. Nepicastat (SYN117; RS-25560-197) has been studied as a possible treatment for congestive heart failure, and appears to be well tolerated as such.
[1]. Stanley WC, et al. Catecholamine modulatory effects of nepicastat (RS-25560-197), a novel, potent and selective inhibitor of dopamine-beta-hydroxylase. Br J Pharmacol. 1997 Aug;121(8):1803-9. [2]. Stanley WC, et al. Cardiovascular effects of nepicastat (RS-25560-197), a novel dopamine beta-hydroxylase inhibitor. J Cardiovasc Pharmacol. 1998 Jun;31(6):963-70. [3]. Sabbah HN, et al. Effects of dopamine beta-hydroxylase inhibition with nepicastat on the progression of left ventricular dysfunction and remodeling in dogs with chronic heart failure. Circulation. 2000 Oct 17;102(16):1990-5. [4]. Beliaev A, et al. Synthesis and biological evaluation of novel, peripherally selective chromanyl imidazolethione-based inhibitors of dopamine beta-hydroxylase. J Med Chem. 2006 Feb 9;49(3):1191-7.