A Randomized, Open-Label Study of the Tolerability of Three Local Anesthetic Formulations in Conjunction With NGX-4010 for the Treatment of Neuropathic Pain

This study is a randomized, open-label multi-center evaluation of the tolerability of treatment with NGX-4010 in conjunction with pre-patch topical application of one of three 4% lidocaine-based local anesthetic products. Eligible subjects will have moderate to severe neuropathic pain secondary to painful diabetic neuropathy (PDN), postherpetic neuralgia (PHN) or HIV-associated neuropathy (HIV-AN), with average numeric pain rating scale (NPRS) scores during screening of 3 to 8 (inclusive).