Discovery of potent, selective and orally active TRPV1 antagonists for the relief of pain

MEDI 317

Kazunari Nakao, Kazunari.Nakao@pfizer.com1, Satoshi Nagayama1, Yuji Shishido1, Misato Hirano1, Masaki Sudo1, Junji Takada2, and Yoshihito Kanai2. (1) Discovery Chemistry Research, Global Research & Development, Pfizer Japan Inc, 5-2 Taketoyo, Aichi, Japan, (2) Discovery Biology Research, Global Research & Development, Pfizer Japan Inc, 5-2 Taketoyo, Aichi, Japan
Vanilloid receptor 1 (TRPV1) is a ligand gated non-selective cation channel and recognized as a polymodal nociceptor that integrates multiple pain stimuli. A major distribution of TRPV1 is in the sensory fibers, which are bipolar neurons having somata in sensory ganglia. The peripheral fibers of these neurons innervate the skin, the mucosal membranes, and almost all internal organs. A body of studies using TRPV1 agonists and antagonists have suggested that TRPV1 positive nerves are thought to participate in a variety of physiological responses, including nociception. Based on both the tissue distribution and the roles of TRPV1, TRPV1 antagonists would have good therapeutic potentials for pain relief.

We began with a high through put screening of the Pfizer sample bank and identified several lead compounds. The modification of these compounds led us to the identification of potent, selective and orally active TRPV1 antagonists. This presentation will cover the identification and characterization of unique peripherally restricted TRPV1 antagonists suitable for clinical development.