Axonyx Announces Results of Curtailed Phase III Clinical Trials for Phenserine in Alzheimer's Disease

Axonyx Inc. (NASDAQ: AXYX) announced today the top line
results of an analysis of its two curtailed Phase III clinical trials
(AX-CL-09/010) with Phenserine, in development for mild to moderate
Alzheimer's disease (AD). Results following 12 weeks of treatment, as
measured by the Alzheimer's Disease Assessment Scale, cognitive
subscale (ADAS cog) and Clinical Interview Based Impression of Change
with caregiver input (CIBIC+), did not demonstrate a statistically
significant benefit of Phenserine treatment over placebo. Patient
recruitment for these studies had previously been halted and the
planned 26-week treatment period shortened based on previously
released results of a 375-patient trial (AX-CL-06) which had showed no
statistically significant differences between Phenserine and placebo.
There were no safety or tolerability concerns associated with
Phenserine treatment.
   The Company had originally planned to recruit 450 patients for
each of the two identically designed studies in order for each trial
to potentially detect a statistically significant clinical benefit.
When the results of the first Phase III trial in early 2005 failed to
show efficacy, patient recruitment for these two ongoing Phase III
trials was halted. Those patients already enrolled were generally
limited to receive only 12 (instead of the planned 26) weeks of study
treatment and for the sake of the analysis the data from both trials
were combined. The Company feels that the results of its analysis are
consistent with and confirm the prior decision to curtail the studies.
   The combined trials recruited 255 (instead of the planned 900)
mild to moderate probable AD patients from 72 clinical sites in 10
countries. Throughout the 12 week treatment period patients were
regularly assessed using standard cognition and memory assessments.
The primary efficacy parameters were the ADAS cog and CIBIC+.
According to a pre-agreed analysis and reporting strategy, secondary
outcomes of efficacy were not to be analysed if the primary endpoints
were not met. Neither of the two Phenserine doses used showed a
significant benefit as compared to placebo treatment.
   The Company continues to evaluate the whole Phenserine program.
There is an ongoing examination of the interim results, reported
earlier, from its ongoing Phase IIB trial. The Phase IIB trial seeks
to evaluate the potential ability of Phenserine to lower the levels of
beta-amyloid precursor protein ((beta)-APP) and beta-amyloid (A(beta))
levels in the plasma and cerebrospinal fluid (CSF) in AD patients
following six (6) months of treatment. The reduction of (beta)-APP and
A(beta) may lead to a slowing of disease progression.
   Phenserine is a highly selective acetylcholinesterase inhibitor
(AChE-I) that breaks down a neurotransmitter in the brain important in
memory and cognition. Unlike other AChE-I's which only suppress the
activity of the enzyme, Phenserine has been shown to have two
mechanisms of action: (1) the inhibition of the AChE enzyme, and (2)
in preclinical studies the inhibition of the synthesis of A(beta), the
protein in the brain that is thought by many to be a potential cause
of Alzheimer's disease and its progression.

   About Axonyx

   Axonyx Inc. is a U.S.-based biopharmaceutical company engaged in
the acquisition and development of proprietary pharmaceutical
compounds for the treatment of Central Nervous System disorders. The
Company currently has three compounds in development for Alzheimer's
disease, namely Phenserine - a potential symptomatic and disease
progression treatment of mild to moderate Alzheimer's Disease (AD),
Posiphen(TM) - a potential disease progression treatment for AD now in
Phase I, and BisNorCymcerine (BNC) - a potential symptomatic treatment
of severe AD now in pre-Investigational New Drug (IND) stage.

   This press release may contain forward-looking statements or
predictions. These statements represent our judgment to date, and are
subject to risks and uncertainties that could materially affect the
Company, including those risks and uncertainties described in the
documents Axonyx files from time to time with the SEC, specifically
Axonyx's annual report on Form 10-K. Specifically, with respect to our
drug candidates Phenserine, Posiphen(TM) and BisNorCymcerine, Axonyx
cannot assure that: any preclinical studies or clinical trials,
whether ongoing or conducted in the future, will prove successful, and
if successful, that the results can be replicated; safety and efficacy
profiles of any of its drug candidates will be established, or if
established, will remain the same, be better or worse in future
clinical trials, if any; pre-clinical results related to cognition and
the regulation of beta-APP will be substantiated by ongoing or future
clinical trials, if any, or that any of its drug candidates will be
able to improve the signs or symptoms of their respective clinical
indication or slow the progression of Alzheimer's disease; any of its
drug candidates will support an NDA filing, will be approved by the
FDA or its equivalent, or if approved, will prove competitive in the
market; or that Axonyx will have or obtain the necessary financing to
support its drug development programs. Axonyx undertakes no obligation
to publicly release the result of any revisions to such
forward-looking statements that may be made to reflect events or
circumstances after the date hereof or to reflect the occurrence of
unanticipated events.