Transient receptor potential vanilloid type 1 antagonists: a patent review (2011 – 2014)

Abstract

Introduction: Transient receptor potential vanilloid type 1 (TRPV1) is a nonselective cation channel that can be activated by noxious heat, low pH and vanilloid compounds such as capsaicin. Since TRPV1 acts as an integrator of painful stimuli, TRPV1 antagonists can be used as promising therapeutics for new types of analgesics.

Areas covered: This review article covers the patents that claim TRPV1 antagonists and were published during 2011 – 2014. The patent evaluation is organized according to the applicant companies, and the representative chemical entities with important in vitro and in vivo data are summarized.

Expert opinion: Many pharmaceutical companies showed promising results in the discovery of potent small molecule TRPV1 antagonists, and recently, a number of small molecule TRPV1 antagonists have been advanced into clinical trials. Unfortunately, several candidate molecules showed critical side effects such as hyperthermia and impaired noxious heat sensation in humans, leading to their withdrawal from clinical trials. Some TRPV1 antagonists patented in recent years (2011 – 2014) overcame these undesirable side effects, making the development of TRPV1 antagonists much more promising.

Keywords:

• capsaicin
• transient receptor potential
• TRPV1
• TRPV1 antagonist
• vanilloid
• VR1
• VR1 antagonist

Acknowledgements

The authors thank Ms. Haes Sal Ha and Dr. So Young Ahn at Dr. Ahn International Patent Law Office, and Ms. Jieun Byun and Ms. Minkyung Cho at Ewha Womans University for searching and collecting patent files.

Declaration of interest

This work was supported by the grant from National Leading Research Lab (NLRL) program (2011-0028885) through the Ministry of Science, ICT & Future Planning (MSIP) and National Research Foundation of Korea (NRF). Y Lee, PK Sharma and S Choi are employees, and S Hong and M Cui are students of Ewha Womans University, Seoul, Korea. J Lee is an employee of Seoul National University and an inventor of some Grünenthal GmbH. patents. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Notes

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