Axonyx Reports Phenserine Associated with Significant Amyloid Reduction in Phase I Trial; Results Support Dual Mechanisms of Act

Axonyx Inc. (NASDAQ:AXYX) today reported a significant
reduction in the plasma levels of beta-amyloid 1-42 (A beta-42) in
healthy human subjects treated with Phenserine for 35 days. This
additional analysis was recently completed as part of the program to
identify a partner for the further development of Phenserine.
   Six healthy men and six healthy women were enrolled in this
multiple-dose Phase I study. Subjects were treated with Phenserine
10mg twice daily for 28 days and Phenserine 15mg twice daily for an
additional week. Plasma samples were collected on Days 1, 28, 29, and
35, with plasma A beta-42 assessments available for 11 subjects.
Samples were collected in accordance with a pre-defined
pharmacokinetic sampling schedule.
-0-
*T
Sample day                                   Plasma A beta-42
                                           Mean (pg/mL)+/- SEM
----------------------------------------------------------------------
Day 1 (prior treatment)                       102.2 +/- 2.6
----------------------------------------------------------------------
Day 35 (prior treatment)                      101.9 +/- 2.8
----------------------------------------------------------------------
Day 35 (2 hrs post treatment)                 81.3 +/- 6.2(a)
----------------------------------------------------------------------
((a) p less than 0.01 relative to baseline)
*T
   At two hours following dosing on Day 35, there was a statistically
significant decrease of A beta-42 relative to pre-treatment levels (p
less than 0.01). This effect was observed at approximately 30 minutes
after the time of maximal plasma Phenserine concentrations.
Furthermore, the decline in plasma A beta-42 concentrations on day 35
consistently coincided with the increase in plasma Phenserine
concentrations following dosing. There were no unexpected safety or
tolerability concerns associated with Phenserine treatment in the 12
healthy subjects.
   Amyloid is thought by many to be key in the development and
progression of AD and reduction of A beta-42 may potentially result in
slowing the onset and progression of the disease. The Company
previously reported interim analyses of its Phase IIb beta amyloid
trial, which appeared to show an effect of Phenserine on levels of
beta amyloid, although the variability of data in that study and the
size of that trial could not support the potential of a statistically
significant outcome. While the absence of a placebo group in the
results reported today calls for caution when interpreting these
results, they are consistent with effects of Phenserine on A beta-42
observed in pre-clinical placebo controlled studies. Thus, the Company
considers these results to support Phenserine's dual mechanisms of
action, which would differentiate it as a potential treatment for
Alzheimer's disease.

   About Phenserine

   Phenserine is a highly selective inhibitor of acetylcholinesterase
(AChEI), an enzyme that breaks down the neurotransmitter
acetylcholinesterase, a neurotransmitter important to memory and
cognitive function. Unlike other AChEI'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)
an ability to lower levels of beta-amyloid- a peptide thought to play
a key role in causing the alterations in the brain which lead to the
symptoms and progression of Alzheimer's disease.

   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 BisNorCymserine (BNC) -- a potential symptomatic
treatment of severe AD now in pre-Investigational New Drug (IND)
stage. The Company is looking to identify licensing partners to
further the development of Phenserine.

   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 BisNorCymserine, 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.