Therapeutic conotoxins: a US patent literature survey.

INTRODUCTION: Conotoxins are a large family of bioactive peptides derived from cone snail venom. They target specific classes of ion channels and other membrane proteins and may have therapeutic value, primarily in the management of pain. AREAS COVERED: The authors surveyed the US patent literature covering conotoxins, and their potential therapeutic applications. They describe the various subclasses of conotoxins that are the subject of current patent applications and their therapeutic indications. Limitations that may preclude broader application of these molecules are discussed and strategies for overcoming these limitations are presented. EXPERT OPINION: Despite more than 25 years of intense global conotoxin research, only one molecule has successfully reached the market. Several other conotoxin-derived candidates failed in clinical trials, indicating that 'from the bench into the clinic' translation has been more difficult than originally anticipated. Nevertheless, we are optimistic that the potent activities of these molecules and the potential for improving their biopharmaceutical properties may lead to next-generation drug candidates with favorable pharmacological properties.