Lidocaine and Tetracaine Cream to Treat Postherpetic Neuralgia (PHN)

A Randomized, Double-Blind, Crossover Study Comparing Pliaglis™ (Lidocaine and Tetracaine) Cream 7%/7% to Placebo Cream When Applied for 60 Minutes in the Treatment of Patients With Postherpetic Neuralgia

Pliaglis™ (lidocaine and tetracaine) Cream 7%/7% is a topical local anesthetic cream that forms a pliable peel on the skin when exposed to air. When applied to intact skin, Pliaglis provides local dermal analgesia by the release of lidocaine and tetracaine from the peel into the skin. Pliaglis is currently approved in the United States for use on intact skin in adults to provide topical local analgesia for superficial dermatological procedures such as dermal filler injection, pulsed dye laser therapy, and facial laser resurfacing. This study will evaluate lidocaine and tetracaine cream 7%/7% for the treatment of pain associated with postherpetic neuralgia (PHN).

The objectives of the study are 1) to compare the clinical efficacy of lidocaine and tetracaine cream 7%/7% with placebo cream in the treatment of neuropathic pain associated with postherpetic neuralgia (PHN) and 2) to monitor the nature and frequency of adverse events following a single, 60-minute application of lidocaine and tetracaine cream 7%/7% and placebo cream.

Pain will be rated using the Numeric Pain Rating Scale (NPRS). Patients will rate: Worst pain over the last 24 hours, Least pain over the last 24 hours, Average pain over the last 24 hours, Present pain intensity.

Inclusion Criteria: Clinical diagnosis of PHN. Painful PHN areas not located on the face, eye, or in the hair. At least 3 months post-vesicle crusting. Exclusion Criteria: Has broken skin at the target treatment site. Is currently on certain prescription medications. Doesn't meet criteria due to physical exam findings or medical history. Female that is pregnant, breastfeeding, or of childbearing potential and not practicing adequate birth control.