Novel Topical Treatment for Postherpetic Neuralgia

DESCRIPTION (provided by applicant): The goal of this project is to develop a novel topical drug delivery vehicle to treat postherpetic neuralgia [PHN). PHN is defined as pain in the affected dermatome that persists or appears after the rash of herpes zoster (HZ) has healed. Although many cases of PHN resolve over time, for many patients the pain is chronic, causing a devastating impact on quality of life. Systemic treatments for PHN are associated with undesirable adverse effects, which can be particularly problematic for elderly patients. Topical treatments such as capsaicin cream, acetylsalicylic acid (aspirin), anesthetic creams, and lidocaine patches either require multiple daily applications or are limited in their use due to the potential for elevated systemic absorption of the topical compound. In previous work, Biomedical Development Corporation (BDC) has developed a novel polymer-based coating composition that is useful for several biomedical applications. The coating is capable of sustained topical drug delivery. The objective of this project is to use these coatings as a treatment for the pain associated with postherpetic neuralgia. The Specific Aims of the grant are as follows: Specific Aim 1: Formulate Coatings for the Treatment of Postherpetic Neuralgia Specific Aim 2: Demonstrate Efficacy of Coatings in a Human Clinical Trial Relevance to Public Health: Herpes zoster (shingles) is one of the most common neurologic diseases in the U.S. Although there have been no systematic attempts to investigate the prevalence of post herpetic neuralgia, estimates have ranged from 500,000 to 1 million in the U.S. The incidence of PHN among those with herpes zoster ranges from 10 to 70 percent and increases with advancing age and the intractability of the pain may also increase with age. The incidence of herpes zoster, and therefore the incidence of PHN, is predicted to increase in the coming decades because of both the aging population and as a consequence of childhood varicella vaccination. The ongoing spontaneous pain and particularly the allodynic component of PHN can be debilitating and can lead to co-morbid conditions such as depression, social isolation, anxiety and sleep disturbance, as well as increased health care utilization.