NeurogesX Presents Two Posters at 61st Annual American Academy of Neurology Annual Meeting

Evaluation of Neurologic Safety following Treatment with Qutenza(TM) (NGX-4010)

Identification of Impact of PHN and PDN on Health Care Costs

SAN MATEO, Calif., April 29 /PRNewswire-FirstCall/ -- NeurogesX, Inc. (Nasdaq: NGSX), a biopharmaceutical company focused on developing and commercializing novel pain management therapies, announced today the presentation of two posters at the 61st Annual American Academy of Neurology (AAN) meeting in Seattle, Washington. These posters, titled "Neurologic Safety of Treatment with NGX-4010, a High-Concentration Capsaicin Patch, in Patients with Postherpetic Neuralgia" and "Impact of Postherpetic Neuralgia and Painful Diabetic Peripheral Neuropathy on Health Care Costs," summarized the results of two sets of analyses.

"Neurologic Safety of Treatment with NGX-4010, a High-Concentration Capsaicin Patch, in Patients with Postherpetic Neuralgia," was led by Miroslav Backonja, MD, of the University of Wisconsin-Madison, and Jeffrey Tobias, MD, Chief Medical Officer of NeurogesX. The integrated analyses examined the effects of Qutenza(TM) (NGX-4010) treatment on neurologic function in patients with posteherpetic neuralgia (PHN). Combined data from four 12-week, controlled studies in over 700 patients showed that there appeared to be no detrimental neurological effects after treatment with Qutenza as measured by light brush, pinprick, vibration and warmth sensations compared with controls. In addition, combined data from almost 300 patients evaluated in two open-label, 1-year repeat treatment studies appeared to show no detrimental neurologic effects of repeated treatment with Qutenza. The most common adverse reactions observed in these clinical trials were transient application site reactions (pain and/or erythema) that were mostly mild to moderate in intensity.

NeurogesX submitted a new drug application (NDA) for Qutenza for the treatment of neuropatic pain associated with PHN to the U.S. Food and Drug Administration (FDA) in October 2008. Recently, a marketing authorization application (MAA) for Qutenza received a positive opinion from the Committee for Medicinal Products for Human Use (CHMP) recommending approval for peripheral neuropathic pain in non-diabetic adults either alone or in combination with other medicinal products for pain. NeurogesX is currently awaiting the European Commission's decision on the CHMP's opinion.

"Impact of Postherpetic Neuralgia and Painful Diabetic Peripheral Neuropathy on Health Care Costs," presented by Christopher J. Panarites, Ph.D. of NeurogesX, identified patterns of health care utilization and costs among PHN and painful diabetic neuropathy (PDN) patients, as well as matched controls. Dr. Panarites and colleagues analyzed a large managed care claims database for the calendar years 2005 and 2006. Results indicated that total annual post-diagnosis costs for PHN and PDN patients averaged $14,535 and $40,705, respectively. In addition, PHN and PDN cases had significantly higher costs compared with matched controls for total costs, costs for outpatient/professional services and pharmacy costs (p less than or equal to 0.002 for all comparisons). Inpatient costs did not significantly differ between PHN and PDN cases and matched controls.

About Neuropathic Pain

Neuropathic pain is a type of chronic pain that results from injury to, or dysfunction of, nerves in the central or peripheral nervous systems. Peripheral neuropathic pain is an inappropriate sensation of pain that results when injured or dysfunctional nerve endings send aberrant pain signals to the brain, in the absence of harmful stimuli. It can result from viruses, in cases of PHN and painful HIV-distal sensory polyneuropathy (HIV-DSP), or diseases, such as diabetes.

An estimated 8% of the world's population suffers from neuropathic pain. Treatments to address the estimated 6.0 million U.S. neuropathic pain sufferers generated over $3.5 billion in 2007 U.S. sales, while an estimated 3.0 million people in Europe suffer from neuropathic pain. The market for neuropathic pain is quickly growing due to the rise in the aging population, diabetes, life expectancy for HIV-positive individuals, and heightened awareness among the medical community. Peripheral neuropathic pain syndromes can be difficult to treat and current treatment options are often limited by poor tolerability, the need for titration, and administration of multiple daily doses.

About NeurogesX, Inc.

NeurogesX (NASDAQ: NGSX) is a biopharmaceutical company focused on developing and commercializing novel pain management therapies. Its initial focus is on chronic peripheral neuropathic pain, including PHN, HIV-DSP and PDN. NeurogesX' late stage product portfolio is led by its product candidate Qutenza, a dermal patch designed to manage pain associated with peripheral neuropathic pain conditions, that the Company believes offers significant advantages over other pain therapies. NeurogesX submitted a new drug application (NDA) for Qutenza to the U.S. Food and Drug Administration (FDA) in October 2008 for PHN, which was accepted for filing by the FDA in December 2008. A marketing authorization application (MAA) for Qutenza received a positive opinion from the Committee for Medicinal Products for Human Use (CHMP) recommending approval for peripheral neuropathic pain in non-diabetic adults alone or in combination with other medicinal products for pain. NeurogesX is currently awaiting the European Commission's decision on the CHMP's opinion.

NeurogesX' second most advanced product candidate, NGX-1998, is a topically applied, liquid formulation containing a high concentration of capsaicin designed to treat pain associated with neuropathic pain conditions. NGX-1998 has completed three Phase 1 studies and NeurogesX is currently evaluating the timing of entering Phase 2 development.

NeurogesX' early stage product pipeline includes pre-clinical compounds, which are prodrugs of acetaminophen and various opioids. The company has evaluated these compounds in vitro and in vivo and is currently seeking development partners for these programs.

Safe Harbor Statement

This press release contains forward-looking statements for purposes of the Private Securities Litigation Reform Act of 1995 (the "Act"). NeurogesX disclaims any intent or obligation to update these forward-looking statements, and claims the protection of the Safe Harbor for forward-looking statements contained in the Act. Examples of such statements include, but are not limited to, the size, scope and growth of potential markets for NeurogesX' product candidates; and the expected benefits of NeurogesX' product candidates and its plans with regard to seeking potential development partners for its early stage product pipeline. Such statements are based on management's current expectations, but actual results may differ materially due to various risks and uncertainties, including, but not limited to; positive results in clinical trials may not be sufficient to obtain FDA or European regulatory approval; any regulatory approvals which are received may be limited to certain indications; NeurogesX' product candidates may have unexpected adverse side effects or inadequate therapeutic efficacy; physician or patient reluctance to use Qutenza or NGX-1998, if approved, or the inability of physicians to obtain sufficient reimbursement for such procedures; potential alternative therapies; maintaining adequate patent or trade secret protection without violating the intellectual property rights of others; and other difficulties or delays in, clinical development, obtaining regulatory approval, market acceptance and commercialization of NeurogesX' product candidates and the advantages of NeurogesX' product candidates over other pain therapies. For further information regarding these and other risks related to NeurogesX' business, investors should consult NeurogesX' filings with the Securities and Exchange Commission.

    NeurogesX, Inc.                         The Ruth Group
    Stephen Ghiglieri                       Sara Ephraim (investors)
    Chief Financial Officer                 (646) 536-7002
    (650) 358-3310                          sephraim@theruthgroup.com

                                            Janine McCargo (media)
                                            (646) 536-7033
                                            jmccargo@theruthgroup.com

SOURCE NeurogesX, Inc.