NeurogesX Phase 3 Study in Post-Herpetic Neuralgia Meets Primary Endpoint

NeurogesX Inc., a privately held specialty pharmaceutical company,
today announced positive results from a multi-center, double-blind,
controlled Phase 3 trial of Transacin(TM) (NGX-4010), the Company's
novel high-concentration trans-capsaicin dermal patch, in patients
with post-herpetic neuralgia (PHN). The study met its pre-specified
primary endpoint with patients reporting statistically significant
pain reduction after a single one-hour application of Transacin,
(p=0.001). A significant reduction in pain was noted during the first
week following treatment (p=0.04) and was maintained throughout the
12-week study period. At 12 weeks, more than one-half of all subjects
treated with Transacin reported improvement in their condition, as
measured by the Patient Global Impression of Change scale.

The study was conducted at 53 clinical sites in the U.S.
Four-hundred and two patients suffering from PHN were randomized to a
single, one-hour treatment with Transacin or to a matching,
low-concentration capsaicin control patch. Study subjects were then
followed for 12 weeks. Pain was recorded daily by study subjects using
the Numeric Pain Rating Scale of 0 (no pain) to 10 (worst possible
pain).

"Transacin has the potential to provide an important therapeutic
alternative to patients suffering from post-herpetic neuralgia, a
frequent, yet difficult-to-manage neuropathic pain condition that
affects one in five shingles patients," said Misha-Miroslav Backonja,
M.D., an investigator in the study and Director of Research and
Education of the University of Wisconsin Pain Treatment Center in
Madison, Wisconsin. "There is a great need for new treatments that can
provide relief to patients with this painful condition."

"There is a very large unmet medical need in the treatment of
neuropathic pain, and this is an important step toward providing an
effective, peripherally acting treatment option," stated Jeffrey
Tobias, M.D., Chief Medical Officer at NeurogesX. "We are continuing
to analyze the study results and anticipate presenting the findings at
a scientific conference early next year."

"This study is significant validation for Transacin and for
NeurogesX, and holds promise for many long-suffering patients with
neuropathic pain. We believe that a peripherally acting therapy
without the traditional side effects experienced in current therapies
will be well received both by physicians and their patients," said
Anthony A. DiTonno, NeurogesX President and CEO. "These data, combined
with our previously reported positive Phase 3 results with Transacin
in painful HIV-associated neuropathy (HIV-AN), will form the basis of
a Marketing Authorization Application for European Union regulatory
approval in the first half of 2007."

The Company's current Transacin development plan includes filing a
New Drug Application (NDA) with the U.S. Food and Drug Administration
including data from its PHN and HIV-AN programs in mid-2008. To
provide the required data for the NDA, NeurogesX is currently
enrolling patients in two confirmatory Phase 3 studies, one in PHN at
sites in the U.S. and Canada, and one in HIV-AN at sites in the U.S.,
Canada, the United Kingdom and Australia.

Additional information about NeurogesX's Phase 3 studies is
available at http://www.clinicaltrials.gov/ct/show/NCT00321672?order=6
and at http://clinicaltrials.gov/ct/show/NCT00300222?order=1.

About Transacin (NGX-4010)

Transacin is a topical, physician-administered patch containing a
high concentration of trans-capsaicin, a synthetic form of the
naturally occurring TRPV1 agonist capsaicin. Unlike current treatment
approaches for neuropathic pain that include opioids and other agents
- which act on the central nervous system and can cause drowsiness or
other systemic side effects - the patch is designed to act
peripherally in the skin, where the pain frequently originates. Due to
the novel patch delivery system and dermal site of action of
Transacin, the potential for safety issues or side effects that
negatively impact quality of life is expected to be low.

About NeurogesX

NeurogesX is a privately held specialty pharmaceutical company
focused on the development of novel treatments for the management of
neuropathic pain. The Company's initial products are focused on the
treatment of chronic pain in the areas of post-herpetic neuralgia
(PHN), painful HIV-associated neuropathy (HIV-AN) and painful diabetic
neuropathy (PDN). NeurogesX intends to file for marketing approval in
Europe in the first half of 2007 and plans to file an NDA in the U.S.
in 2008. Additional information about NeurogesX can be found at
www.neurogesx.com.

NeurogesX is a trademark of NeurogesX, Inc.