Sodium channel blockers: a patent review (2010 - 2014)

Abstract

Introduction: Abnormal activity of voltage-gated sodium channels (VGSCs) is related to several pathological processes, including cardiac arrhythmias, epilepsy, cancer, neurodegenerative diseases, spasticity, chronic and neuropathic pain. As such VGSCs are considered important therapeutic targets.

Areas covered: This review summarized > 30 patents on sodium channel blockers, having beneficial effects on a number of diseases. Pubmed, http://www.sciencedirect.com/ , SciFinder Scholar, http://ep.espacenet.com/ were used as sources for this review and patents filed 2010 and July 2014 were examined.

Expert opinion: Over the past 4 years we assisted to a continuous effort in the discovery of new sodium channel blockers by a large number of pharmaceutical companies. All the different chemical classes presented, and here analyzed, could represent an important breakout but, the lack of precise structural information, with the incompleteness of the biological data hampered the possibility to understand the real 'state of the art' of any of these inventions. Upon analysis of a number of patents in this review, it remains clear that the major hurdle faced by the discovery teams is the ability to develop subtype selective compounds. The development of subtype selective blockers could, in theory, lead to more effective and better tolerated compounds.

Keywords: chronic pain; neuropathic pain; sodium channel blockers; sodium channel isoforms.