Discovery, oral pharmacokinetics and in vivo efficacy of velusetrag, a highly selective 5-HT(4) receptor agonist that has achieved proof-of-concept in patients with chronic idiopathic constipation.

Utilization of Theravance's multivalent approach to drug discovery towards 5-HT(4) receptor agonists with a focus on identification of neutral (non-charged at physiological pH) secondary binding groups is described. Optimization of a quinolone-tropane primary binding group with a chiral 2-propanol linker to a range of neutral secondary binding group motifs, for binding affinity and functional potency at the 5-HT(4) receptor, selectivity over the 5-HT(3) receptor, oral pharmacokinetics, and in vivo efficacy in models of GI motility, afforded velusetrag (TD-5108). Velusetrag has achieved proof-of-concept in patients with chronic idiopathic constipation.