NeurogesX, Inc. (Nasdaq: NGSX) announced that the U.S. Food and Drug Administration (FDA) agreed to its proposed study to evaluate Qutenza(TM) in patients with post-herpetic neuralgia (PHN) following pretreatment with an FDA-approved topical anesthetic. As part of its ongoing new drug application (NDA) review, the FDA wants to determine whether pretreatment with an FDA-approved topical anesthetic would provide similar tolerability to the topical agent used as a pretreatment in the clinical development program.