Addex Appoints Laurent Massuyeau as Head of Business Development

Geneva, Switzerland, 18 April 2008 - Addex Pharmaceuticals is pleased
to announce the appointment of Laurent Massuyeau as head of business
development.

Mr. Massuyeau joins Addex from Idenix Pharmaceuticals Inc., where he
was executive director of European commercial operations. He brings
to Addex 7 years of big pharma business development experience as
well as 10 years of sales and marketing experience.

Vincent Mutel, CEO, said, "Laurent's expertise and network gained
through his work in the US and Europe will strengthen our growing
business development efforts and are particularly valuable for our
expansion plans."

Immediately prior to joining Addex Mr. Massuyeau was executive
director of European commercial operations at Idenix Pharmaceuticals
Inc. From 2004-2006 he was business unit director for Lilly, France,
a division of Eli Lilly & Co., leading groups responsible for
strategy, business development, alliance management, sales and
marketing services as well as information technology. From 2002-2004
Mr. Massuyeau was manager corporate strategy & business development
at Lilly's headquarters in Indianapolis. From 2000-2001, Mr.
Massuyeau was sales manager for Lilly for the New England area in the
U.S. Prior to that, beginning in 1995, he held a succession of
positions in Europe for Lilly. From 1992-1995 he worked for animal
health company Virbac Laboratories Ltd., managing sales in Europe and
Asia. Mr. Massuyeau holds an MBA from INSEAD, graduated from Nantes
Veterinary School as doctor of veterinary medicine, and holds a
masters degree in biochemistry from University of Medicine Paris V.

"I am excited to join such a rapidly growing dynamic company and look
forward to the many exciting challenges ahead," said Massuyeau.

About Addex

Addex Pharmaceuticals discovers and develops allosteric modulators,
an emerging class of small molecule therapeutic agents. Allosteric
modulation may offer more sophisticated ways to normalize biological
signaling compared to classical orthosteric agonist or antagonist
drugs. Allosteric, literally translated from its Greek roots, means:
other site. Thus, allosteric modulators bind receptors at sites that
are distinct from the binding sites of classical small molecule
orthosteric agonist and antagonist drugs.

The most advanced drug candidate, ADX10059, a negative allosteric
modulator (NAM) of metabotropic glutamate receptor 5 (mGluR5),
recently demonstrated clinically and statistically significant
efficacy in separate Phase IIa clinical trials in gastroesophageal
reflux disease (GERD) patients and migraine headache patients.

The Addex allosteric modulation discovery and development platform
has been additionally validated through collaborations with Merck &
Co., Inc. and Johnson & Johnson.
Contacts

Chris Maggos
Head of IR & Communications
Addex Pharmaceuticals
+41 22 884 15 11
chris.maggos@addexpharma.com

Disclaimer
The foregoing release contains forward-looking statements that can be
identified by terminology such as "not approvable", "continue",
"believes", "believe", "will", "remained open to exploring", "would",
"could", or similar expressions, or by express or implied discussions
regarding Addex Pharmaceuticals Ltd, its business, the potential
approval of its products by regulatory authorities, or regarding
potential future revenues from such products. Such forward-looking
statements reflect the current views of Addex Pharmaceuticals Ltd
regarding future events, and involve known and unknown risks,
uncertainties and other factors that may cause actual results with
allosteric modulators of mGluR4, mGluR2, mGluR5 or other therapeutic
targets to be materially different from any future results,
performance or achievements expressed or implied by such statements.
There can be no guarantee that allosteric modulators of mGluR4,
mGluR2 or mGluR5 will be approved for sale in any market or by any
regulatory authority. Nor can there be any guarantee that allosteric
modulators of mGluR4, mGluR2, mGluR5 or other therapeutic targets
will achieve any particular levels of revenue (if any) in the future.
In particular, management's expectations regarding allosteric
modulators of mGluR4, mGluR2, mGluR5 or other therapeutic targets
could be affected by, among other things, unexpected actions by our
partners, unexpected regulatory actions or delays or government
regulation generally; unexpected clinical trial results, including
unexpected new clinical data and unexpected additional analysis of
existing clinical data; competition in general; government, industry
and general public pricing pressures; the company's ability to obtain
or maintain patent or other proprietary intellectual property
protection. Should one or more of these risks or uncertainties
materialize, or should underlying assumptions prove incorrect, actual
results may vary materially from those anticipated, believed,
estimated or expected. Addex Pharmaceuticals is providing the
information in this press release as of this date and does not
undertake any obligation to update any forward-looking statements
contained in this press release as a result of new information,
future events or otherwise.