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Updated: Jul 6, 2026

Contractility Measurements of Human Uterine Smooth Muscle to Aid Drug Development
Published on: January 26, 2018
The in vivo gastrointestinal activity of TD-5108, a selective 5-HT(4) receptor agonist with high intrinsic activity
D T Beattie1, S R Armstrong, J P Shaw
1Theravance, Inc., 901 Gateway Boulevard, South San Francisco, CA, 94080, USA. dbeattie@theravance.com
Abstract:
The in vivo preclinical pharmacodynamic profile of TD-5108, a selective 5-HT(4) receptor agonist with high intrinsic activity, was compared to that of the clinically studied gastrointestinal pro-kinetic agents, tegaserod, cisapride and mosapride. The activity of TD-5108 was evaluated in guinea pig colonic transit, rat oesophageal relaxation and dog gastrointestinal smooth muscle contractility models. Subcutaneous administration of TD-5108, tegaserod, cisapride and mosapride increased guinea pig colonic transit (rank order of potencies: TD-5108 > tegaserod > cisapride > mosapride). Following intravenous and intraduodenal dosing, TD-5108, tegaserod, cisapride and mosapride produced dose-dependent relaxation of the rat oesophagus. On a molar basis, TD-5108 was approximately twofold less potent than tegaserod following intravenous dosing but 6- or 86-fold more potent than cisapride or mosapride, respectively, and 9- or 18-fold more potent than tegaserod or cisapride, respectively, after intraduodenal administration. Orally dosed TD-5108 increased the contractility of the canine antrum, duodenum and jejunum with higher potency than tegaserod. The selective 5-HT(4) receptor agonist, TD-5108, demonstrates robust in vivo activity in the guinea pig, rat and dog gastrointestinal tracts.
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