NeurogesX' NGX-1998 Well-Tolerated Treatment Demonstrated Clear Dose-Response In Patients

NGX-1998 Phase 2 Study Data Presented at World Congress on Pain

Multiple Posters on Qutenza ® Presented by Partner Astellas

SAN MATEO, Calif., Aug. 30, 2012 (GLOBE NEWSWIRE) -- NeurogesX, Inc. (OTCQB:NGSX) (OTCBB:NGSX), a specialty pharmaceutical company focused on developing and commercializing a portfolio of novel non-opioid, pain management therapies, today presented data from its Phase 2 study on NGX-1998 at the 14th World Congress on Pain in Milan, Italy. NGX-1998 is the Company's next generation liquid formulation of prescription-strength capsaicin.

The presentation highlighted the Company's Phase 2 clinical trial, a multicenter, placebo-controlled, double-blind trial in postherpetic neuralgia (PHN). The results from the trial indicate that NGX-1998 may be a safe, efficacious and convenient treatment for patients with PHN and other types of neuropathic pain. NeurogesX plans to enable a Phase 3 clinical trial in neuropathic pain by the end of 2012.

Stephen J. Peroutka, MD, PhD, Chief Medical Officer of NeurogesX, said, "NGX-1998's liquid formulation allows for easier administration than our already approved capsaicin patch. Our Phase 2 results indicate that with a single, five minute treatment with NGX-1998, subjects experienced pain relief for as long as three months. The data from our Phase 2 study also confirm that NGX-1998 requires no topical anesthetic pre-treatment, making the therapy even more convenient for providers to administer."

Patients enrolled in the study had experienced pain for least 6 months following healing of a herpes zoster lesion, and had a Mean Numeric Pain Rating Scale (NPRS) score between 4 to 9, inclusive. Patients were randomized into one of three groups: NGX-1998 capsaicin 20% solution, NGX-1998 capsaicin 10% solution or placebo, according to an unequal allocation scheme of 2:2:1. Based on safety and tolerability results, it was determined that no topical anesthetic pre-treatment was required for treatment with NGX-1998. No patients discontinued the study due to adverse events, and the incidence of adverse events and serious adverse events in patients treated with NGX-1998 were similar to the placebo-treated group.

Data from the study indicated that NGX-1998 was well-tolerated and resulted in improved outcomes on validated measures of neuropathic pain. Dose response was demonstrated, and NGX-1998 showed a greater magnitude of response on the pain intensity scale correlating with the concentration of the formulation: 20% > 10% > placebo. In addition, true placebo is an appropriate control for further trials.

In addition to the Company's presentation on NGX-1998, NeurogesX' partner Astellas Pharma Europe Ltd., the European headquarters of Tokyo-based Astellas Pharma Inc., presented a number of posters on Qutenza ® (8% capsaicin patch) at the World Congress on Pain. When combined, the abstracts on the 8% capsaicin patch presented at the conference provide data on over 2,500 treated patients.

One poster was entitled "A Swedish prospective observational multicenter study to evaluate efficacy and safety in patients with peripheral neuropathic pain receiving their first Qutenza ® treatment." The study found that Qutenza ® is an efficacious and tolerable treatment for subgroups of patients with peripheral neuropathic pain. While there are limitations to open label observational studies, researchers concluded the study supports the clinical trials previously reported in patients with PHN and HIV-Associated Peripheral Neuropathy.

Data presented in another poster, "High Concentration Capsaicin Patch Improves Quality of Life in Patients with Neuropathic Non-Diabetic Pain," led to the conclusion that Qutenza ® reduces the intensity of neuropathic pain and significantly increases quality of life in patients who had previously been treated for their neuropathic pain. These results came from a prospective observational study of patients in the Czech Republic.

Under its Commercial License Agreement with Astellas, NeurogesX shares in the growing market opportunity for Qutenza in the Astellas territory, which includes the EU, the Middle East and Africa, through ongoing royalties, as well as potential sales milestones. In the United States, Qutenza is approved for the management of PHN.

About NeurogesX, Inc.

NeurogesX, Inc. (OTCQB:NGSX) (OTCBB:NGSX) is a specialty pharmaceutical company focused on developing and commercializing a portfolio of novel non-opioid, pain management therapies to address unmet medical needs and improve patients' quality of life.

The Company's lead product, Qutenza ®, is currently approved in the United States and the European Union. Qutenza ® is now available in the United States for the management of neuropathic pain associated with postherpetic neuralgia (PHN). In Europe, Qutenza ® is being marketed by Astellas Pharma Europe Ltd. (Astellas), the European affiliate of Tokyo-based Astellas Pharma Inc., for the treatment of peripheral neuropathic pain in non-diabetic adults, either alone or in combination with other medicinal products for pain.

The Company's 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 such as PHN. NGX-1998 has completed four Phase 1 clinical trials and one Phase 2 clinical trial in PHN patients, and the Company believes that NGX-1998 is ready to enter Phase 3 development.

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 statements regarding: potential efficacy and safety of NGX-1998 and Qutenza; the convenience of use of NGX-1998; NGX-1998 being ready for entry into Phase 3 development and enabling a Phase 3 clinical trial of NGX-1998 by the end of 2012. 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: NGX-1998 may fail to demonstrate sufficient safety or efficacy in clinical trials to support further development or potential marketing approval; Qutenza may fail to demonstrate sufficient efficacy to support further development for additional indications; difficulties or delays in further clinical development of NGX-1998, including difficulties or delays in initiating Phase 3 clinical trials; Qutenza, NGX-1998 and NeurogesX' other product candidates may have unexpected adverse side effects; delay or prevention of development activities due to unexpected expenses or a lack of sufficient resources; and difficulties or delays in identifying potential strategic partners for Qutenza and NGX-1998 and negotiating and entering into agreements with such entities. For further information regarding these and other risks related to NeurogesX' business, investors should consult NeurogesX' filings with the Securities and Exchange Commission.
CONTACT: NeurogesX, Inc.         Stephen Ghiglieri         Executive Vice President, COO and CFO         (650) 358-3310                  Additional Contacts:         The Ruth Group         Stephanie Carrington / Nicole Greenbaum (investors)         (646) 536-7017 / 7009 /                  Victoria Aguiar (media)         (646) 536-7013