Disclosure of Shareholdings in Accordance with Stock Market Rules

Addex Pharmaceuticals Ltd. was informed by:

The disclosure of shareholdings is triggered by the expiration of a lockup agreement on May 22, 2008 that also comprised 28 other shareholders holding each less than 3% of the voting rights in Addex Pharmaceuticals Ltd.

(1) Sofinnova Capital IV FCPR with its management company, Sofinnova Partners SA, and its principal office at 17, rue de Surène, 75008 Paris (France) holds 806,648 shares.

(2) Index Ventures II (Jersey) L.P., with its principal office at P.O. Box 641, No. 1 Seaton Place, St. Helier Jersey JE4 8YJ Channel Islands, holds 233,955 shares; Index Ventures II (Delaware) L.P., with its principal office at 1209 Orange Street, Wilmington, Country of New Castle, Delaware (USA), holds 430,148 shares; Index Ventures II GmbH & Co. KG, with its principal office at Max-Joseph-Strasse 7, 80333 Munich (Germany), holds 68,775 shares; Index Ventures II Parallel Entrepreneur Fund (Jersey-A) L.P., with its principal office at P. O. Box 641, No. 1 Seaton Place, St. Helier Jersey JE4 8YJ Channel Islands, holds 7,851 shares; Index Ventures II Parallel Entrepreneur Fund (Jersey-B) L.P., with its principal office at P. O. Box 641, No. 1 Seaton Place, St. Helier Jersey JE4 8YJ Channel Islands, holds 12,307 shares; and Yucca Partners L.P. (Jersey Branch) on behalf of Index Co-Investment Scheme, with its principal office at Whitelay Chambers, Don Street, St. Helier, Jersey JE4 9WG, Channel Islands, holds 12,752 shares.

(3) TVM V Life Science Ventures GmbH & Co. KG with its principal office at Maximilian Strasse 35C, 80539 Munich (Germany) holds 705,726 shares.

(4) Polytechnos Venture Fund II L.P., with its principal office at Alexander House, 13-15 Victoria Road, St. Peter Port, Guernsey GY1 3ZD, Channel Islands, holds 192,177 shares; Polytechnos Venture Fund II GmbH & Co. KG with its registered office at Huyssenallee 44, 45128 Essen (Germany) holds [47,871] shares; Polytechnos Partners & Team GmbH with its principal office at Huyssenallee 44, 45128 Essen (Germany) holds 2,426 shares.

(5) Vincent Mutel, Rolle/Switzerland, holds 205,150 shares.

Addex Pharmaceuticals Ltd (www.addexpharma.com) 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.

Chris Maggos

Head of IR & Communications

Addex Pharmaceuticals

+41 22 884 15 11

The foregoing release may contain 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, future economic performance or prospects, and, by their very nature, involve inherent risks and uncertainties, both general and specific, whether known or unknown, and/or any other factor that may materially differ from the plans, objectives, expectations, estimates and intentions expressed or implied in such forward-looking statements. Such may in particular cause actual results with allosteric modulators of mGluR2, mGluR4, mGluR5, mGluR7 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 mGluR2, mGluR4, mGluR5, mGluR7 will be approved for sale in any market or by any regulatory authority. Nor can there be any guarantee that allosteric modulators of mGluR2, mGluR4, mGluR5, mGluR7 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 mGluR2, mGluR4, mGluR5, mGluR7 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 Ltd 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, except as may be required by applicable laws.