Neuropathic Pain: V3381
Summary
V3381 is a novel drug candidate that is being developed as a treatment for neuropathic pain. V3381, originally licensed from Chiesi Farmaceutici (Chiesi), has a dual mechanism of action, that of an NMDA antagonist and an MAO-A inhibitor, which gives it the potential to modulate pain at both central and peripheral sites.
Background
Neuropathic pain is a chronic form of pain related to damage to nerves and their signalling processes, and unlike other forms of pain, is generally non-responsive to current analgesics, does not diminish over time and can increase in both intensity and area. This type of pain occurs in later stages of diabetes, post-herpetic neuralgia (shingles), side effects of chemotherapy, trigeminal (facial) neuralgia, HIV infection, spinal cord injuries and other nerve injuries (eg. amputation).
Espicom Business Intelligence estimated the 2003 global market for drugs approved for neuropathic pain at U.S. $2.5 billion, despite limited response rates and efficacy, tolerance and dependency issues, and other side effects of current therapies.
According to Pain Therapeutics-Drugs, Markets and Companies, October 2005, the worldwide market for pain is estimated at U.S. $50.0 billion for 2005 and is expected to increase to U.S. $75.0 billion by 2010. 2004 pain management prescription sales were estimated by Pharmaceutical Executive to be U.S. $20.6 billion and are expected to increase to U.S. $29.8 billion by 2008.
The pain management market has grown significantly in recent years, driven by increased demand from patients, better physician responsiveness, an aging population, increasing numbers of surgical procedures as well as new products and remains one of the most widely researched yet under treated therapeutic areas.
Clinical Studies
V3381 is currently undergoing a Phase IIa study in patients suffering from neuropathic pain resulting from long-standing diabetes.
In two proof-of-concept studies V3381 achieved a reduction of the area and intensity of pain reported by volunteers in a model of neuropathic pain. A maximum tolerated dose study in healthy volunteers was completed. In August 2006 Vernalis began a Phase IIa study. The randomised, double-blind, crossover trial is designed to assess safety, pharmacokinetics and preliminary efficacy of repeat dosing of V3381, with efficacy being assessed on a numerical point pain rating scale recorded using daily diaries. The trial, which is being conducted in the U.S. and Canada, will include approximately 30 patients and is planned to complete in mid-2007.