Zamifenacin fumarate

Zamifenacin fumarate (UK-76654 fumarate) is a potent gut-selective muscarinic M3 receptor antagonist. Zamifenacin significantly reduces colonic motility in irritable bowel syndrome[1].

Signaling Pathways >> Neuronal Signaling >> mAChR

Signaling Pathways >> GPCR/G Protein >> mAChR

Research Areas >> Metabolic Disease

Muscarinic M3 receptor[1]

Zamifenacin exhibits moderate oral bioavailability (mouse 26%, rat 64%, dog 100%) and Cmax (mouse 92, rat 905, dog 416 ng/mL) following oral administration (mouse 13.2, rat 20 and, dog 5 mg/kg)[2]. Zamifenacin exhibits terminal elimination half-lives (mouse 2.1, rat 6.0 and, dog 1.1 h) due to high plasma clearance (68, 35, and 39 mL/min/kg respectively combined with large volumes of distribution (12.5, 19.0, and 3.5 L/kg respectively) following intravenous administration (mouse 5.3, rat 5.0 and, dog 1.0 mg/kg)[2]. Animal Model: Male CDl mice (mean weight 23 g)[2] Dosage: 5.3 mg/kg for i.v.; 13.2 mg/kg for oral (Pharmacokinetic Analysis) Administration: Intravenous administration and oral administration Result: Oral bioavailability (26%), Cmax (92 ng/mL), T1/2 (1.1 h). Animal Model: Male and female CD rats (mean weight 210 g)[2] Dosage: 5.0 mg/kg for i.v.; 20 mg/kg for oral (Pharmacokinetic Analysis) Administration: Intravenous administration and oral administration Result: Oral bioavailability (64%), Cmax (905 ng/mL), T1/2 (6.0 h). Animal Model: Male and two female beagle dogs (13-16 kg)[2] Dosage: 1.0 mg/kg for i.v.; 5 mg/kg for oral (Pharmacokinetic Analysis) Administration: Intravenous administration and oral administration Result: Oral bioavailability (100%), Cmax (416 ng/mL), T1/2 (1.1 h).

[1]. Houghton LA, et al. Zamifenacin (UK-76, 654) a potent gut M3 selective muscarinic antagonist, reduces colonic motor activity in patients with irritable bowel syndrome. Aliment Pharmacol Ther. 1997 Jun;11(3):561-8.

[2]. Beaumont KC, et al. Pharmacokinetics and metabolism of Zamifenacin in mouse, rat, dog and man. Xenobiotica. 1996 Apr;26(4):459-71.