Securities Registration (foreign Private Issuer) (f-3)

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As filed with the Securities and Exchange Commission on April 7, 2021

Registration No. 333-

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM F-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

Addex Therapeutics Ltd
(Exact name of registrant as specified in its charter)


Switzerland (State or other jurisdiction of incorporation or organization)		Not applicable (I.R.S. Employer Identification Number)

Chemin des Mines 9,
CH-1202 Geneva,
Switzerland
Tel: +41 22 884 15 55
(Address and telephone number, including area code of registrant's principal executive offices)

Addex Pharmaceuticals Inc.
650 California Street
San Francisco, CA 94108
Tel: +1 415 429 2591
(Name, address, including zip code, and telephone number, including area code, of agent for service)


Copies to:
Joshua A. Kaufman Marc Recht Cooley LLP 55 Hudson Yards New York, New York 10001 +1 212 479 6000	David C. Boles Cooley (UK) LLP Dashwood 69 Old Broad Street London EC2M 1QS United Kingdom +44 20 7583 405	Frank Gerhard Homburger AG Prime Tower Hardstrasse 201 CH-8005 Zürich, Switzerland +41 43 222 10 00

Approximate date of commencement of proposed sale to the public:
From time to time after the effective date of this registration statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. ý

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a registration statement pursuant to General Instruction I.C. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. o

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.C. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933.

Emerging growth company ý

If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. o

The term "new or revised financial accounting standard" refers to any updated issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012.

CALCULATION OF REGISTRATION FEE

Title Of Each Class Of Securities To Be Registered	Amount to be Registered(2)	Proposed Maximum Offering Price Per Unit	Proposed Maximum Aggregate Offering Price	Amount of Registration Fee




Primary Offering:

Shares, nominal value CHF 1.00 per share(1)		—(3)	$150,000,000(4)	$16,365.00(4)

Secondary Offering:

Shares, nominal value CHF 1.00 per share(1)	7,704,600	—(5)	$13,682,086(6)	$1,493.72

Total Primary and Secondary Offering			$163,682,086	$17,858.72

(1): These shares may be represented by American Depositary Shares, or ADSs, each of which represents six shares of the registrant. ADSs issuable upon deposit of the shares registered hereby were registered pursuant to a separate registration statement on Form F-6 (File No. 333-235561).
(2): There are being registered hereunder such indeterminate number of shares as may be sold by the registrant from time to time at indeterminate prices, with the maximum aggregate public offering price not to exceed $150,000,000. In addition, up to 7,704,600 shares may be sold from time to time pursuant to this registration statement by the selling shareholder named herein. In addition, pursuant to Rule 416 under the Securities Act of 1933, as amended, or the Securities Act, the shares being registered hereunder include such indeterminate number of shares as may be issuable with respect to the shares being registered hereunder as a result of stock splits, stock dividends, or similar transactions.
(3): With respect to the Primary Offering, the proposed maximum aggregate price per unit of each class of securities will be determined from time to time by the registrant in connection with the issuance by the registrant of the securities registered hereunder and is not specified as to each class of securities pursuant to the General Instruction II.C. of Form F-3 under the Securities Act.
(4): Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(o) under the Securities Act.
(5): With respect to the Secondary Offering, the proposed maximum offering price per ordinary share will be determined from time to time in connection with, and at the time of, sale by the holders of such securities named in the registration statement.
(6): Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) under the Securities Act, based upon the average of the high and low prices of the registrant's ADSs on the Nasdaq Capital Market on April 1, 2021, of $10.75 and $10.56. Pursuant to Rule 457(p) under the Securities Act, the registrant hereby offsets the total registration fee due under this registration statement by the amount of the filing fee associated with the unsold securities from the registrant's Form F-1 Registration Statement, filed with the Commission on December 17, 2019 (File No. 333-235554) as amended by Post-Effective Amendment No. 1 on April 27, 2020, registering 11,439,511 Shares (the "Prior Registration Statement"). The associated filing fee of $2,568.79 paid on December 17, 2019 is hereby used to offset the current registration fee due. The offering of such securities registered under the Prior Registration Statement will be deemed terminated as of the date of effectiveness of this registration statement.

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

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The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities, and we are not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED April 7, 2021

PROSPECTUS

Addex Therapeutics Ltd

$150,000,000 of Shares Offered by the Company
and
7,704,600 Shares Offered by the Selling Shareholder
(Each Including Shares in the Form of American Depositary Shares)

This prospectus will allow us to issue shares from time to time at prices and terms to be determined in each offering up to a maximum aggregate offering price of $150,000,000. Each share may be issued in the form of American Depositary Shares or ADSs. Each ADS represents the right to receive six shares of Addex Therapeutics Ltd.

In addition, the selling shareholder named in this prospectus, or the selling shareholder, may offer and sell from time to time up to 7,704,600 of our shares represented by ADSs. We will not receive any of the proceeds from the sale of shares by the selling shareholder. We are registering these shares pursuant to a registration rights agreement that we entered into with the selling shareholder and other shareholders. The selling shareholder may offer and sell its shares in public or private transactions, or both. These sales may occur at fixed prices, at market prices prevailing at the time of sale, at prices related to prevailing market prices, or at negotiated prices. See "Plan of Distribution" for more information on how the selling shareholder may conduct sales of their ordinary shares.

This prospectus describes the general terms of these securities and the general manner in which these securities will be offered. We will provide you with the specific terms of any primary offering in one or more supplements to this prospectus. The prospectus supplements will also describe the specific manner in which these securities will be offered and may also supplement, update or amend information contained in this document. You should read this prospectus and any prospectus supplement, as well as any documents incorporated by reference into this prospectus or any prospectus supplement, carefully before you invest.

The securities covered by this prospectus may be offered through one or more underwriters, dealers or agents, or directly to purchasers. For additional information on the methods of sale, you should refer to the section titled "Plan of Distribution" in this prospectus and in any applicable prospectus supplement. If any underwriters or agents are involved in the sale of our securities with respect to which this prospectus is being delivered, the names of such underwriters or agents and any applicable fees or commissions and over-allotment options will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds that either we or the selling shareholder expect to receive from such sale will also be set forth in a prospectus supplement.

Our ADSs are listed on the Nasdaq Capital Market, or Nasdaq, under the symbol "ADXN." Our shares are listed on the SIX Swiss Exchange, or SIX, under the symbol "ADXN." On April 1, 2021, the last reported sale price of our ADSs on Nasdaq was $10.56 per ADS and the closing price of our shares on SIX on April 1, 2021 was CHF 1.67 per share, which is equivalent to $1.77 per share based on an exchange rate between the Swiss franc and the U.S. dollar of $1.0613 per CHF 1.0 as of April 1, 2021, or $10.63 per ADS, after giving effect to the 6:1 share-to-ADS ratio. The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on Nasdaq or any securities market or other securities exchange of the securities covered by the prospectus supplement. Prospective purchasers of our securities are urged to obtain current information as to the market prices of our securities, where applicable.

Under the registration statement to which this prospectus forms a part, we may not sell our securities in a primary offering with a value exceeding one-third of our public float in any 12-month period (unless our public float rises to $75.0 million or more). The aggregate market value of our outstanding voting and nonvoting common equity held by non-affiliates computed in accordance with General Instruction I.B.5 to Form F-3 is $48.95 million, based on 27,618,907 shares held by non-affiliates on April 1, 2021 and a $1.77 closing price of the common stock on SIX on April 1, 2021. We have not offered any securities pursuant to General Instruction I.B.5 to Form F-3 in the prior 12-month period that ends on and includes the date of this prospectus.

Investing in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should consider carefully the risks that we have described on page 8 of this prospectus under the caption "Risk Factors" and under similar headings in the other documents that are incorporated by reference in this prospectus. We may also include specific risk factors in supplements to this prospectus under the caption "Risk Factors." This prospectus may not be used to sell our securities unless accompanied by a prospectus supplement.

Neither the U.S. Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is , 2021.

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TABLE OF CONTENTS


ABOUT THIS PROSPECTUS			i
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS			iii
PROSPECTUS SUMMARY			1
RISK FACTORS			8
USE OF PROCEEDS			9
CAPITALIZATION			10
SELLING SHARHOLDER			11
DESCRIPTION OF SHARE CAPITAL AND ARTICLES OF ASSOCIATION			12
COMPARISON OF SWISS LAW AND DELAWARE LAW			18
DESCRIPTION OF AMERICAN DEPOSITARY SHARES			27
PLAN OF DISTRIBUTION			39
SERVICE OF PROCESS AND ENFORCEMENT OF JUDGMENTS			43
EXPENSES			44
LEGAL MATTERS			44
EXPERTS			44
WHERE YOU CAN FIND MORE INFORMATION			45
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE			46

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the U.S. Securities and Exchange Commission, or the SEC, as a "shelf" registration process.

Under this shelf registration, we may offer shares, which may be issued in the form of ADSs, described in this prospectus from time to time in one or more offerings up to a total aggregate offering price of $150,000,000, and the selling shareholder named in this prospectus may also offer and sell up to 7,704,600 of our shares represented by ADSs under this prospectus. This prospectus only provides you with a general description of the securities we may offer. Each time we or, if required under the Securities Act, the selling shareholder sells securities described herein, we will provide prospective investors with a supplement to this prospectus that will contain specific information about the terms of that offering, including the specific amounts, prices and terms of the securities offered. The prospectus supplement may also add to, update or change information contained in this prospectus. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change information contained in this prospectus or in any documents that we have incorporated by reference into this prospectus. Accordingly, to the extent inconsistent, information in this prospectus is superseded by the information in any prospectus supplement. You should carefully read this prospectus, any applicable prospectus supplement and any related free writing prospectus, together with the information incorporated herein by reference as described under the heading "Incorporation of Certain Information by Reference," before investing in any of the securities offered.

THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A PRIMARY SALE OF SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.

Unless otherwise indicated or the context otherwise requires, references in this prospectus to "Addex," "Addex Therapeutics," "Addex Therapeutics Ltd," "the Company," "we," "us" and "our" refer to Addex Therapeutics Ltd together with its subsidiaries. Our reporting currency is the Swiss franc. The terms "dollar," "USD" or "$" refer to U.S. dollars and the terms "Swiss franc" and "CHF" refer to the legal currency of Switzerland.

This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under the heading "Where You Can Find More Information."

Neither we, the selling shareholder, nor any agent, underwriter or dealer has authorized any person to give any information or to make any representation other than those contained or incorporated by reference in this prospectus, any applicable prospectus supplement or any related free writing prospectus prepared by or on behalf of us or to which we have referred you. This prospectus, any applicable supplement to this prospectus or any related free writing prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the registered securities to which they relate, nor do this prospectus, any applicable supplement to this prospectus or any related free writing prospectus constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction.

You should not assume that the information contained in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate on any date subsequent to the date set forth on the front of the document or that any information we have incorporated by reference is correct on any date subsequent to the date of the document incorporated by reference, even though

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this prospectus, any applicable prospectus supplement or any related free writing prospectus is delivered, or securities are sold, on a later date.

For investors outside the United States: Neither we nor the Selling Shareholder has done anything that would permit the offering or possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the securities described herein and the distribution of this prospectus outside the United States.

We own trademarks for Addex Therapeutics in Switzerland. All other trade names, trademarks and service marks of other companies appearing in this prospectus are the property of their respective holders. Solely for convenience, the trademarks and trade names in this prospectus may be referred to without the ® and ™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend to use or display other companies' trademarks and trade names to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, any prospectus supplement and the information incorporated by reference in this prospectus and any prospectus supplement contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Exchange Act of 1934, as amended, or the Exchange Act, that involve substantial risks and uncertainties. Although our forward-looking statements reflect the good faith judgment of our management, these statements can only be based on facts and factors currently known by us. Consequently, these forward-looking statements are inherently subject to risks and uncertainties, and actual results and outcomes may differ materially from results and outcomes discussed in the forward-looking statements.

All statements other than present and historical facts and conditions contained in this prospectus, any prospectus supplement and the information incorporated by reference in this prospectus and any prospectus supplement including statements regarding our future results of operations and financial positions, business strategy, plans and our objectives for future operations, are forward-looking statements. The words "anticipate," "believe," "continue" "could," "estimate," "expect," "intend," "may," "might," "ongoing," "objective," "plan," "potential," "predict," "should," "will" and "would," or the negative of these and similar expressions identify forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

•: the development of our product candidates, including statements regarding the timing of initiation, completion and the outcome of pre-clinical studies or clinical trials and related preparatory work, the period during which the results of the studies or trials will become available and our research and development programs with respect to our product candidates;
•: the impact of COVID-19 on our business and operations;
•: our ability to obtain and maintain regulatory approval of our product candidates in the indications for which we plan to develop them, and any related restrictions, limitations or warnings in the label of an approved drug or therapy;
•: our plans to collaborate, or statements regarding the ongoing collaborations, with partner companies;
•: our plans to research, develop, manufacture and commercialize our product candidates;
•: the timing of our regulatory filings for our product candidates;
•: the size and growth potential of the markets for our product candidates;
•: our ability to raise additional capital;
•: our commercialization, marketing and manufacturing capabilities and strategy;
•: our expectations regarding our ability to obtain and maintain intellectual property;
•: our ability to attract and retain qualified employees and key personnel;
•: our ability to contract with third party suppliers and manufacturers and their ability to perform adequately;
•: how long we will qualify as an emerging growth company or a foreign private issuer;
•: our estimates regarding future revenue, expenses and needs for additional financing;
•: our belief that our existing cash, cash equivalents and marketable securities as of December 31, 2020 and the proceeds raised through the capital increase executed on January 8, 2021 will be

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sufficient to fund our operating expenses and capital expenditure requirements through at least the second quarter 2022; and

•: regulatory developments in the United States, European Union and other jurisdictions.

As a result of these factors, we cannot assure you that the forward-looking statements in this prospectus, any prospectus supplement and the information incorporated by reference in this prospectus and any prospectus supplement will prove to be accurate. Furthermore, if our forward-looking statements prove to be inaccurate, the inaccuracy may be material. In light of the significant uncertainties in these forward-looking statements, you should not regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified time frame or at all. We undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

You should read this prospectus, any prospectus supplement and the information incorporated by reference in this prospectus and any prospectus supplement completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

This prospectus, any prospectus supplement and the information incorporated by reference in this prospectus and any prospectus supplement may contain market data and industry forecasts that were obtained from industry publications. These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. While we believe the market position, market opportunity and market size information included in this prospectus, any prospectus supplement and the information incorporated by reference in this prospectus and any prospectus supplement is generally reliable, such information is inherently imprecise.

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PROSPECTUS SUMMARY

The following summary highlights information contained elsewhere in this prospectus and does not contain all of the information that you need to consider in making your investment decision. We urge you to read this entire prospectus, including the more detailed consolidated financial statements, notes to the consolidated financial statements and other information incorporated by reference from our other filings with the SEC or included in any applicable prospectus supplement. Investing in our securities involves risks. Therefore, carefully consider the risk factors set forth in any prospectus supplements and in our most recent filings with the SEC including our Annual Report on Form 20-F for the year ended December 31, 2020 and reports on Form 6-K since January 1, 2021, as well as other information in this prospectus and any prospectus supplements and the documents incorporated by reference herein or therein, before purchasing our securities. Each of the risk factors could adversely affect our business, operating results and financial condition, as well as adversely affect the value of an investment in our securities.

Overview

We are a clinical-stage pharmaceutical company focused on the development and commercialization of an emerging class of novel orally available small molecule drugs known as allosteric modulators. Allosteric modulators target a specific receptor or protein and alter the effect of the body's own signaling molecules on their target through a novel mechanism of action. These innovative small molecule drug candidates offer several potential advantages over conventional non-allosteric molecules and may offer an improved therapeutic approach to existing drug treatments. To date, our research and development efforts have been primarily focused on building a portfolio of proprietary drug candidates based on our allosteric modulator development capability. The allosteric modulator principle has broad applicability across a wide range of biological targets and therapeutic areas, but our primary focus is on G-protein coupled receptors, or GPCR, targets implicated in neurological diseases, where we believe there is a clear medical need for new therapeutic approaches.

Using our allosteric modulator discovery capabilities, we have developed a pipeline of proprietary clinical and preclinical stage drug candidates. We or our partners are developing these clinical and preclinical stage proprietary drug candidates for diseases for which there are no approved therapies or where improved therapies are needed. These include levodopa induced dyskinesia associated with Parkinson's disease, or PD-LID, non-parkinsonian dystonia (including blepharospasm), or dystonia, epilepsy, addiction (including alcohol use disorder), Charcot-Marie-Tooth type 1A neuropathy, or CMT1A, post-traumatic stress disorder, or PTSD, and other neurodegenerative diseases. Some of these indications are classified as rare diseases that may allow for orphan drug designation by regulatory agencies in major commercial markets, such as the United States, Europe and Japan. Orphan drug designation may entitle the recipient to benefits, in the jurisdiction granting the designation, such as market exclusivity following approval and assistance in clinical trial design, a reduction in user fees or tax credits related to development expenses.

We are developing our lead drug candidate, dipraglurant, as a metabotropic glutamate receptor subtype 5 negative allosteric modulator, or mGlu5 NAM, for the treatment of PD-LID. We are planning to initiate a placebo-controlled Phase 2b/3 pivotal clinical trial of dipraglurant in PD-LID patients in the second quarter of 2021, pending removal of governmental restrictions and lessening of the impact of the global coronavirus pandemic on the U.S. healthcare system, which delayed our previously anticipated initiation in the first quarter of 2020. The clinical trial is expected to be conducted at approximately 50 sites in the United States and target enrollment of approximately 140 patients. We have received orphan drug designation from the United States Food and Drug Administration, or FDA, for dipraglurant in PD-LID and expect to report topline results in the fourth quarter of 2022. In parallel, we are developing an extended release formulation of dipraglurant as a novel orally available mGlu5 NAM for the treatment of blepharospasm. We expect to start an

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exploratory placebo-controlled Phase 2 clinical trial in blepharospasm patients using the current immediate release formulation of dipraglurant in the second quarter of 2021.

Our partnered drug candidate, ADX71149 is a novel orally active metabotropic glutamate receptor subtype 2 positive allosteric modulator, or mGlu2 PAM for the treatment of epilepsy. Our partner, Janssen Pharmaceuticals, Inc., or Janssen, a subsidiary of Johnson & Johnson is planning to initiate a placebo-controlled Phase 2a proof of concept clinical trial of ADX71149 in epilepsy patients in the second quarter of 2021. Under our agreement with Janssen, Janssen is responsible for financing the development and commercialization, if any, of ADX71149.

We are also conducting a research program under our strategic partnership with Indivior UK Limited, or Indivior, to discover novel orally available gamma-aminobutyric acid subtype B receptor positive allosteric modulators, or GABAB PAMs. We are currently in clinical candidate selection and expect to deliver a drug candidate by the end of 2021. Under terms of the agreement with Indivior, we have the right to select drug candidates for development in certain exclusive indications outside of addiction. We plan to develop our selected drug candidate in CMT1A, an indication that has been clinically validated with baclofen, an orthosteric agonist of GABAB.

Allosteric modulators have broad applicability for many clinically validated GPCR targets which are implicated in multiple therapeutic indications. We intend to continue to leverage our scientific expertise in allosteric modulation and our proprietary technology platform to discover novel drug candidates for the treatment of neurological diseases.

Based on our expertise in allosteric modulation, our goal is to build a leading neuroscience company focused on conditions where current treatment options are limited and where unmet medical needs exist. Our business strategy includes the possibility of entering into collaborative arrangements with third parties to complete the development and commercialization of our proprietary drug candidates, such as our partnership with Janssen Pharmaceuticals, Inc., or Janssen, a subsidiary of Johnson & Johnson, for ADX71149 and our strategic partnership with Indivior for GABAB PAM. We cannot forecast with any degree of certainty which proprietary products or indications, if any, will be subject to future collaborative arrangements, in whole or in part, and how such arrangements would affect our development plan or capital requirements. To date, we have secured grants and other funding from: The Michael J. Fox Foundation for Parkinson's Research, or MJFF, for the development of dipraglurant for the treatment of PD-LID; the National Institute of Drug Abuse, or NIDA, to generate important data on the role of GABAB in addiction; the Swiss Innovation Agency, or Innosuisse, to advance our understanding of the role of our drug candidates in neurodegenerative and psychiatric diseases; and the Eurostars Joint Programme, or Eurostars to identify novel drug candidates on mGlu7 NAM for PTSD. As we advance our clinical and preclinical programs, we will continue to apply for subsidies, grants and government or agency sponsored studies that could offset or reduce our development costs.

The development and commercialization of drugs is highly competitive. We compete with a variety of multinational pharmaceutical companies and specialized pharmaceutical companies, including products approved for marketing and/or product candidates under development, for each of the product candidates and each of the indications for which we are developing. Furthermore, government authorities in the United States, at the federal, state and local levels, and in other countries, extensively regulate, among other things, the research, development, testing, manufacture, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, import and export of pharmaceutical products, such as those we are developing. The processes for obtaining regulatory approvals in the United States and in foreign countries, along with subsequent compliance with applicable statutes and regulations, require the expenditure of substantial time and financial resources.

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Research and Development Portfolio

Using our allosteric modulator platform and drug discovery and development expertise, we have established a portfolio of clinical and preclinical programs, both internally and with partners.

Internally Developed Product Candidates

Dipraglurant for the treatment of levodopa-induced dyskinesia associated with Parkinson's disease. We are developing dipraglurant as a novel orally available mGlu5 NAM for the treatment of PD-LID. PD-LID is a disease with significant commercial opportunity as improved therapies are needed. We believe that, subject to regulatory approval, dipraglurant may offer an innovative and differentiated treatment approach from existing therapies. In a 28 day Phase 2a placebo-controlled clinical trial, conducted in the United States and Europe, in patients with PD-LID, dipraglurant met its primary end point, was generally well tolerated and no clinically significant abnormalities of safety monitoring parameters occurred. In addition, at Day 1 and Day 14, dipraglurant showed statistically significant effects on PD-LID clinical symptoms, as measured using mAIMs. However, an increasing placebo response resulted in the effect of dipraglurant on PD-LID clinical symptoms not showing statistical significance at Day 28. We have substantially completed the preparation of dipraglurant to start registration studies in PD-LID and expect to initiate a Phase 2b/3 placebo-controlled pivotal clinical trial of dipraglurant in PD-LID patients in the second quarter of 2021, pending removal of governmental restrictions and lessening of the impact of the global coronavirus pandemic on the U.S. healthcare system, which delayed our previously anticipated initiation in the first quarter of 2020. The clinical trial is expected to be conducted at approximately 50 sites in the United States and target enrollment of approximately 140 patients. We have also received orphan drug designation from the FDA for dipraglurant in PD-LID and expect to report topline results in the fourth quarter of 2022.

Dipraglurant, for the treatment of non-Parkinsonian dystonia, including blepharospasm. We are developing an extended release formulation of dipraglurant as a novel orally available NAM for the treatment of blepharospasm. There are many types of dystonia affecting up to 300,000 people in the United States. Blepharospasm is characterized by involuntary muscle contractions and spasms of the eyelid muscles resulting in sustained eyelid closure causing substantial visual disturbance or functional blindness. We expect to start an exploratory placebo-controlled Phase 2 clinical trial in blepharospasm patients using the current immediate release formulation of dipraglurant in the second quarter of 2021. Subject to regulatory approval, we believe that dipraglurant may offer an innovative and differentiated treatment approach for multiple types of dystonia and present a significant commercial opportunity.

Externally Developed Out-licensed Product Candidate

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ADX71149 (mGlu2 PAM) for the treatment of epilepsy. Our partnered drug candidate, ADX71149 is a novel orally active mGlu2 PAM. Our partner, Janssen, has completed Phase 1 and two Phase 2a clinical trials in schizophrenia and anxious depression, respectively. Janssen has conducted several preclinical studies in epilepsy and is planning to initiate a placebo-controlled Phase 2a proof of concept clinical trial of ADX71149 in epilepsy patients in the second quarter of 2021. Under our agreement with Janssen, Janssen is responsible for financing the development and commercialization, if any, of ADX71149.

Material Internal Research Programs

GABAB PAM for the treatment of addiction. Our partner, Indivior, has licensed worldwide rights to our GABAB PAM program and is responsible for all development, manufacture and commercialization of any selected GABAB PAM drug candidates. Under the agreement, we are responsible for executing a research program funded by Indivior to discover novel drug candidates. Indivior has the right to select GABAB PAM drug candidates from our research program. We started the clinical candidate selection phase in the fourth quarter of 2020 and expect IND enabling studies to be initiated in 2022. Indivior's primary focus is addiction, including alcohol use disorder. We believe that addiction is an indication with a significant commercial opportunity. Existing therapies often do not provide effective control of symptoms or have side effects that discourage adherence. Subject to regulatory approval, we believe that GABAB PAM may offer an innovative and differentiated treatment approach from existing therapies and may provide benefit to patients.

GABAB PAM for the treatment of CMT1A. Our license agreement with Indivior provides for a funded research program, under which we have the right to select drug candidates for exclusive development in certain indications outside of addiction, including CMT1A, a rare disease indication. We plan to pursue orphan drug designation for a selected drug candidate for CMT1A. The program is in the clinical candidate selection phase and we expect to initiate IND enabling studies in 2022. We believe an oral small molecule GABAB PAM with a once-a-day dosing and without the adherence-limiting side effects of baclofen, which is currently used off label, could bring benefit to patients and consequently present a strong commercial opportunity for us.

mGlu7 NAM for the treatment of PTSD. We are developing mGlu7 NAMs as a novel orally available treatment to reduce fear memory in PTSD, a disorder that can lead to intense fear and anxiety. Current medication is unspecific and ineffective, with a number of side effects. By selectively targeting mGlu7 with NAMs, the brain circuitries involved in fear and anxiety can be more precisely modulated, potentially resulting in a more focused response and fewer side effects than current therapeutic approaches. Subject to regulatory approval, we believe our mGlu7 NAM may offer an innovative and differentiated treatment approach from existing therapies. We are in late lead optimization and a consortium led by us has been awarded a €4.85 million grant from the Eurostars Joint Programme to advance the program to drug candidate stage.

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Early Stage Internal Research Programs

mGlu2 NAM for the treatment of mild neurocognitive disorders, or mNCD. We are developing mGlu2 NAM as a novel orally available treatment for mNCD associated with Alzheimer's disease, Parkinson's disease and depressive disorders. We are currently optimizing multiple chemical series of highly selective mGlu2 NAMs offering advanced compounds at the late stage of lead optimization.

mGlu4 PAM for the treatment of Parkinson's disease. We are developing mGlu4 PAM as a novel orally available treatment for Parkinson's disease. We are currently optimizing multiple chemical series of highly selective mGlu4 PAMs with compounds in early lead optimization.

mGlu3 PAM for the treatment of neurodegenerative disorders. We are developing mGlu3 PAM as a novel orally available treatment for neurodegenerative disorders. We are currently optimizing multiple chemical series of highly selective mGlu3 PAMs, with compounds in early lead optimization.

Recent Developments

On March 23, 2021, we entered into an addendum (the "Addendum") to the Sale Agency Agreement between us and Kepler Cheuvreux, dated August 24, 2020 (the "Sale Agreement"). The Addendum extended the duration of the Sale Agreement from March 31, 2021 until December 31, 2021, unless terminated earlier by either party. The terms of the Sale Agreement otherwise remain unchanged.

Corporate Information

We are a corporation organized under the laws of Switzerland. Our ADS have been listed on Nasdaq under the symbol "ADXN" since January 29, 2020, and our shares have been listed on SIX since May 2007 under the symbol "ADXN."

Our corporate headquarters is located at Chemin des Mines 9, CH-1202 Geneva, Switzerland, where the telephone number is +41 22 884 1555, and our registered office is located at c/o Addex Pharma SA, Chemin des Aulx 12, CH-1228 Plan-les-Ouates, Geneva, Switzerland. Our website address is www.addextherapeutics.com. The information contained on, or that can be accessed from, our website does not form part of this prospectus. Our agent for service of process in the United States is Addex Pharmaceuticals Inc., 650 California Street, San Francisco, CA 94108.

Summary Risk Factors

Our business is subject to a number of risks of which you should be aware before making an investment decision. You should carefully consider all of the information set forth in this prospectus and, in particular, should evaluate the specific factors set forth in the section titled "Risk Factors" before deciding

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whether to invest in our shares, which may be issued in the form of ADSs. These important risks include, but are not limited to, the following:

•: We will need significant amounts of additional new capital to fund our continued development activities.
•: We cannot guarantee that we will have sufficient funds available in the future to develop and commercialize our current or future drug candidates.
•: We have a history of net losses and negative cash flows, and we expect that such losses will continue for the foreseeable future and that we may never achieve or maintain profitability.
•: We are a development-stage company working with novel approaches to therapeutics, which may not be successful.
•: We have no products on the market and we may never generate revenue from the sale or licensing of product candidates.
•: The future of our business and operations depends on the success of our allosteric modulator development programs, including our most advanced proprietary product candidate, dipraglurant.
•: Our dependence on Janssen to develop and commercialize ADX71149 and Indivior to develop and commercialize our GABA_B PAM program exposes us to significant risks.
•: If third parties on which we depend to conduct our clinical trials do not perform as contractually required, fail to satisfy regulatory or legal requirements or miss expected deadlines, our clinical development program could be delayed and otherwise adversely affected.
•: Our business could be negatively affected by the effects of health epidemics, including the evolving effects of the COVID-19 pandemic, in regions where we or third parties on which we rely have significant manufacturing facilities, concentrations of clinical trial sites or other business operations.
•: Because we rely on third party manufacturing and supply partners, our clinical development supplies and other materials may become limited or interrupted or may not be of satisfactory quality.
•: Our drug candidates must prove their efficacy and safety in rigorous clinical testing that is expensive, time-consuming and may be delayed, suspended or terminated at any time.
•: We face competition from entities that have developed or may develop similar or different product candidates aimed at the indications on which we are focusing.
•: Any commercialization efforts by us will require us to develop sales, marketing and distribution capabilities internally or through arrangements with third parties.

Implications of Being an Emerging Growth Company and a Foreign Private Issuer

Emerging Growth Company

We are an "emerging growth company" as defined in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. As such, we may take advantage of certain exemptions from various reporting requirements that are applicable to other publicly traded entities that are not emerging growth companies. These exemptions include:

•: not being required to comply with the auditor attestation requirements of Section 404(b) of the Sarbanes-Oxley Act of 2002; and

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•: to the extent that we no longer qualify as a foreign private issuer, (1) reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements and (2) exemptions from the requirements of holding a non-binding advisory vote on executive compensation, including golden parachute compensation.

We will remain an emerging growth company until the earliest of: (1) the last day of the first fiscal year in which our annual gross revenues exceed $1.07 billion; (2) the last day of 2025; (3) the date that we become a "large accelerated filer" as defined in Rule 12b-2 under the Exchange Act, which would occur on the last day of any fiscal year that the aggregate worldwide market value of our common equity held by non-affiliates exceeds $700 million as of the last business day of our most recently completed second fiscal quarter; or (4) the date on which we have issued more than $1.0 billion in non-convertible debt securities during any three year period.

Foreign Private Issuer

We are a foreign private issuer as defined in Section 405 of the Securities Act. Even after we no longer qualify as an emerging growth company, as long as we qualify as a foreign private issuer under the Exchange Act we will be exempt from certain provisions of the Exchange Act that are applicable to U.S. domestic public companies, including:

•: the sections of the Exchange Act regulating the solicitation of proxies, consents or authorizations in respect of a security registered under the Exchange Act;
•: the sections of the Exchange Act requiring insiders to file public reports of their stock ownership and trading activities and liability for insiders who profit from trades made in a short period of time; and
•: the rules under the Exchange Act requiring the filing with the U.S. Securities and Exchange Commission, or the SEC, of quarterly reports on Form 10-Q containing unaudited financial and other specific information, and current reports on Form 8-K upon the occurrence of specified significant events.

Foreign private issuers are also exempt from certain more stringent executive compensation disclosure rules. Thus, even if we no longer qualify as an emerging growth company, but remain a foreign private issuer, we will continue to be exempt from the more stringent compensation disclosures required of companies that are neither an emerging growth company nor a foreign private issuer.

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RISK FACTORS

Investing in our securities involves a high degree of risk. You should carefully review the risks and uncertainties described under the heading "Risk Factors" contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in our Annual Report on Form 20-F for the year ended December 31, 2020 as updated by our subsequent filings, some of which are incorporated by reference into this prospectus, before deciding whether to purchase any of the securities being registered pursuant to the registration statement of which this prospectus is a part. Each of the risk factors could adversely affect our business, results of operations, financial condition and cash flows, as well as adversely affect the value of an investment in our securities, and the occurrence of any of these risks might cause you to lose all or part of your investment. Additional risks not presently known to us or that we currently believe are immaterial may also significantly impair our business operations.

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USE OF PROCEEDS

We will retain broad discretion over the use of the net proceeds from the sale of the securities offered by us hereby. Except as described in any applicable prospectus supplement or in any free writing prospectuses that we may authorize to be provided to you in connection with a specific offering, we currently intend to use the net proceeds from the sale of the securities offered hereby to execute the development of our portfolio of proprietary drug candidates based on our allosteric modulator development capabilities. These include dipraglurant, an mGlu5 negative allosteric modulator, for use in Parkinson's disease and dystonia, and our preclinical pipeline. We may also use a portion of the net proceeds for corporate development activities aimed at securing resources from investors, through partnerships and from grant providers to advance our clinical and preclinical programs, as well as our allosteric modulator discovery platform. We will set forth in the applicable prospectus supplement or free writing prospectus our intended use for the net proceeds received from the sale of any securities sold pursuant to the prospectus supplement or free writing prospectus. Pending these uses, we intend to invest the net proceeds in investment-grade, interest-bearing securities. We will not receive any proceeds from the sale of securities by the selling shareholder offered hereby.

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CAPITALIZATION

The following table presents our total capitalization and cash and cash equivalents as of December 31, 2020 on

•: an actual basis; and
•: on an as adjusted basis to give effect to our January 8, 2021 issuance and sale of 6,900,000 new shares of which 6,750,000 were in the form of ADSs, which gross proceeds amounted to CHF 10.1 million ($11.5 million), partially offset by capital increase costs of CHF 1.6 million ($1.7 million).

You should read the financial data in the following table in conjunction with our financial statements and related notes incorporated by reference into this prospectus.

CHF in thousands	Actual as at December 31, 2020			As adjusted as at December 31, 2020

	(audited)			(unaudited)
Cash and cash equivalents		18,695			27,316



Shareholders' equity
Share capital		32,849			39,749
Share premium		286,888			288,446
Reserves		8,579			8,579
Accumulated deficit		(313,706	)		(313,706	)

Total shareholders' equity, net		14,610			23,068

Total capitalization		14,610			23,068

Unless otherwise stated in this prospectus, the number of our shares set forth herein is as of December 31, 2020 and is based on 27,118,774 shares outstanding, but excludes:

•: 6,900,000 new shares of which 6,750,000 were issued in the form of 1,125,000 ADSs in a registered offering executed on January 8, 2021;
•: 5,729,861 treasury shares indirectly held through our wholly-owned subsidiary Addex Pharma SA, on such date;
•: authorized (but unissued) capital of 16,424,317 shares as of December 31, 2020, of which 6,900,000 shares have been issued for the registered offering executed on January 8, 2021;
•: conditional (but unissued) capital of 16,424,317 shares, including 5,866,898 shares reserved for issuance upon exercise of any options or warrants granted in connection with an issuance of bonds, similar obligations or other financial instruments and 10,557,419 shares reserved for issuance pursuant to our equity incentive plans of which 6,967,210 relate to outstanding stock options and subscriptions rights linked to equity sharing certificates granted under our equity incentive plans, each as of December 31, 2020; and
•: 1,700 equity sharing certificates (bons de jouissance / Genussscheine) as of December 31, 2020 have been issued to our 100% owned subsidiary, Addex Pharma SA, of which 199 have been granted under our equity incentive plans with subscriptions rights to 198,750 shares outstanding December 31, 2020. These subscription rights are included in the 10,557,419 of conditional capital referred to above.

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SELLING SHARHOLDER

The shares being offered by the selling shareholder are those currently held by the selling shareholder and those issuable to the selling shareholder upon exercise of certain warrants held by the selling shareholder, who has piggyback registration rights under a registration rights agreement. We are registering the shares in order to permit the selling shareholder to offer the shares for resale from time to time. Except for the ownership of the shares and warrants, the selling shareholder has not had any material relationship with us within the past three years.

The table below lists the selling shareholder and other information regarding the beneficial ownership of the shares held by the selling shareholder. The second column lists the number of shares beneficially owned by the selling shareholder, based on its ownership of the shares and warrants as of January 31, 2021, assuming exercise of the warrants held by the selling shareholder on that date, without regard to any limitation on exercise. The third column lists the percentage of shares beneficially owned by the selling shareholder before the offering. The fourth column lists the number of shares being registered in this prospectus by the selling shareholder. In accordance with the terms of the registration rights agreement with the selling shareholder and certain other holders of our shares and warrants, this prospectus generally covers the resale of that number of shares equal to the number of shares currently held by the selling shareholder and the shares issuable upon exercise of the warrants, determined as if such warrants were exercised in full. The fifth column lists the percentage of shares beneficially owned by the selling shareholder, assuming the sale of all of the shares registered by the registration statemen of which this prospectus forms a part.

The selling shareholder may sell all, some or none of its shares included in this prospectus. See "Plan of Distribution."

Name of Selling Shareholder		Number of shares beneficially owned			Percentage of shares beneficially owned before the offering			Number of shares being registered in the offering			Percentage of shares beneficially owned after the offering

Growth Equity Opportunities Fund IV, LLC(1)			7,704,600			21.3	%		7,704,600			0

(1): Consist of 5,648,690 shares and 2,055,910 shares issuable upon exercise of outstanding warrants directly held by Growth Equity Opportunities Fund IV LLC ("GEO IV") that is wholly owned by New Enterprise Associates 15, L.P ("NEA 15"). The shares directly held by GEO IV are indirectly held by NEA 15, whose general partner is NEA Partners 15, L.P ("NEA Partners 15"). The general partner of NEA Partners 15 is NEA 15 GP, LLC ("NEA 15 LLC"). The individual Managers of NEA 15 LLC, or collectively, the NEA 15 Managers are Forest Baskett, Anthony A. Florence Jr., Joshua Makower, Mohamad Makhzoumi, Scott D. Sandell and Peter W. Sonsini. GEO IV, NEA 15, NEA Partners 15, NEA 15 LLC and the NEA 15 Managers share voting and dispositive power with regard to our securities held directly by GEO IV. The address of Growth Equity Opportunities Fund IV LLC is c/o New Enterprise Associates, Inc., 1954 Greenspring Drive, Suite 600, Timonium, MD 21093.

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DESCRIPTION OF SHARE CAPITAL AND ARTICLES OF ASSOCIATION

The following section describes our issued share capital as of December 31, 2020, summarizes the material provisions of our Articles of Association and highlights certain differences in corporate law in Switzerland and the United States.

Capital structure

There were 2,269 shareholders registered in the share register on December 31, 2020. The distribution of shareholdings is divided as follows:

Number of shares		Number of registered shareholders on December 31, 2020

1 to 100			251
101 to 1,000			944
1,001 to 10,000			946
10,001 to 100,000			114
100,001 to 1,000,000			9
1,000,001 to 10,000,000			5

The shareholder base on December 31, 2020 was constituted as follows:

Shareholder structure according to category of investors (weighted by number of shares)

Private persons	26.85	%
Institutional shareholders	51.34	%
Non identified	21.81	%

Shareholder structure by country (weighted by number of shares)

United States	25.93	%
Switzerland	50.75	%
Other	1.52	%
Non identified	21.81	%

Capital

As of December 31, 2020, the share capital amounted to CHF 32,848,635 consisting of 32,848,635 issued shares with a nominal value of CHF 1 per share. As of December 31, 2020, we indirectly held 5,729,861 of our own shares. These shares are recorded as treasury shares.

Authorized share capital

As of December 31, 2020 and according to the article 3b of the Articles as in force on December 31, 2020, the Board of Directors ("Board") was authorized, at any time until June 9, 2022 to increase the share capital in an amount of CHF 16,424,317 through the issuance of 16,424,317 fully paid registered shares with a nominal value of CHF 1 each. An increase in partial amounts was permitted. The Board shall determine the issue price, the type of payment, the date of issue of new shares, the conditions for the exercise of pre-emptive rights and the beginning date for dividend entitlement. In this regard, the Board was entitled to issue new shares by means of a firm underwriting through a banking institution, a syndicate or another third party with a subsequent offer of these shares to the current shareholders (unless the pre-emptive rights of current shareholders are excluded). The Board was entitled to permit pre-emptive rights that have not been exercised to expire or to place

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these rights and/or shares as to which pre-emptive rights have been granted but not exercised, at market conditions or use them for other purposes in our interest.

The subscription and acquisition of the new shares, as well as each subsequent transfer of the shares, shall be subject to the restrictions set forth in article 5 of the Articles.

The Board was authorized to restrict or exclude the pre-emptive rights of shareholders and allocate such rights to third parties if the shares are to be used:

•: for the acquisition of enterprises, parts of an enterprise, or participations, or for new investments, or, in case of a share placement, for the financing or refinancing of such transactions;
•: for the purpose of the participation of strategic partners (including in the event of a public tender offer) or for the purpose of an expansion of the shareholder constituency in certain investor markets;
•: for the granting of an over-allotment option (Greenshoe) of up to 20% to the banks involved in connection with a placement of shares; or
•: for raising capital in a fast and flexible manner, which would not be achieved without the exclusion of the statutory pre-emptive rights of the existing shareholders.

Conditional share capital

According to article 3c(A) of the Articles, our share capital may be increased by a maximum aggregate amount of CHF 10,557,419 through the issuance of a maximum of 10,557,419 registered shares, which shall be fully paid-in, with a par value of CHF 1 per share by the exercise of option rights or subscription rights attached to equity sharing certificates (bons de jouissance) which our employees, directors and/or consultants are granted according to respective regulations of the Board. The pre-emptive rights of the shareholders are excluded. The acquisition of registered shares through the exercise of option rights or subscription rights granted to the holders of bons de jouissance and the subsequent transfer of the registered shares shall be subject to the transfer restrictions provided in article 5 of the Articles.

According to article 3c(B) of the Articles, our share capital may be increased by a maximum aggregate amount of CHF 5,866,898 through the issuance of a maximum of 5,866,898 registered shares, which shall be fully paid-in, with a par value of CHF 1 per share by the exercise of option and/or conversion rights which are granted to our shareholders and/or in connection with the issue of bonds or other financial instruments by us. In the case of such grants of option and/or conversion rights, the advanced subscription right of shareholders is excluded. The holders of option and/or conversion rights are entitled to receive the new shares. The Board shall determine the terms of the option and/or conversion rights. The acquisition of registered shares through the exercise of option or conversion rights and the subsequent transfer of the registered shares shall be subject to the transfer restrictions provided in article 5 of the Articles.

The Board is authorized to restrict or exclude the advanced subscription rights of shareholders:

•: if the debt or other financial instruments and/or conversion rights or warrants are issued for the purpose of financing or refinancing of the acquisition of enterprises, parts of an enterprise, or participations or new investments;
•: if such debt or other financial instruments and/or conversion rights or warrants are issued on the national or international capital markets and for the purpose of a firm underwriting by a banking institution or a consortium of banks with subsequent offering to the public; or

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•: if such debt or other financial instruments and/or conversion rights or warrants are issued for raising capital in a fast and flexible manner, which would not be achieved without the exclusion of the advanced subscription rights of the existing shareholders.

If the Board excludes the advance subscription rights, the followings shall apply: the issuance of convertible bonds or warrants or other financial market instruments shall be made at the prevailing market conditions (including dilution protection provisions in accordance with market practice) and the new shares shall be issued pursuant to the relevant conversion or exercise rights in connection with bond or warrant issue conditions. Conversion rights may be exercised during a maximum 10 year period, and warrants may be exercised during a maximum 7 year period, in each case from the date of the respective issuance.

Changes in capital

Nominal share capital

December 31, 2018			CHF 28,564,031
December 31, 2019			CHF 32,848,635
December 31, 2020			CHF 32,848,635
Conditional share capital
December 31, 2018			CHF 14,282,015
December 31, 2019			CHF 16,424,317
December 31, 2020			CHF 16,424,317
Authorized share capital
December 31, 2018			CHF 14,282,015
December 31, 2019			CHF 16,424,317
December 31, 2020			CHF 16,424,317

Changes in capital in 2018

On March 16, 2018, we increased our capital from CHF 15,384,988 to CHF 15,526,454 through the issue of 141,466 new registered shares at nominal value of CHF 1 each, in connection with the exercise of equity incentive units.

On March 28, 2018, we increased our capital from CHF 15,526,454 to CHF 28,564,031 through the issue of 13,037,577 new registered shares at nominal value of CHF 1 each, in connection with a private placement to institutional investors.

On June 20, 2018, the shareholders increased the authorized capital from CHF 7,692,494 to CHF 14,282,015 expiring on June 20, 2020 and the conditional capital from CHF 7,551,028 to CHF 14,282,015.

Changes in capital in 2019

On May 17, 2019, we increased our capital from CHF 28,564,031 to CHF 32,848,635 through the issue of 4,284,604 new registered shares at nominal value of CHF 1 each.

On June 19, 2019, the shareholders increased the authorized capital from CHF 9,997,411 to CHF 16,424,317 expiring on June 19, 2021 and the conditional capital from CHF 14,282,015 to CHF 16,424,317.

Changes in capital in 2020

In 2020 there was no change in the share capital of the Company.

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On June 9, 2020 the shareholders resolved to extend the term of the authorized capital to June 9, 2022.

For further information on changes in capital including changes in reserves, refer to the consolidated statements of changes in equity as well as note 13 of the audited consolidated financial statements incorporated by reference into this registration statement.

Shares and participation certificates

Addex has one class of shares, i.e. registered shares with a nominal value of CHF 1 per share. Each share is fully paid up and carries one vote and equal dividend rights, with no privileges. We have no participation certificates (bons de participation / Partizipationsscheine).

Equity Sharing certification

Equity sharing certificates are available for granting to our employees and/or directors and/or consultants under our equity incentive plan. Equity sharing certificates do not form part of the share capital, have no nominal value, and do not grant any right to vote nor to attend meetings of shareholders. There are 1,700 equity sharing certificates (bons de jouissance / Genussscheine). Each equity sharing certificate grants the right to subscribe for 1,000 of our shares and a right to liquidation proceeds calculated in accordance with article 34 of the Articles.

Our shares and equity sharing certificates are not certificated. Shareholders and equity sharing certificate holders are not entitled to request printing and delivery of certificates, however, any shareholder or equity sharing certificate holder may at any time request that we issue a confirmation of its holdings.

Limitations on transferability of shares and nominee registration

A transfer of uncertified shares is affected by a corresponding entry in the books of a bank or depository institution following an assignment in writing by the selling shareholder and notification of such assignment to Addex by the bank or the depository institution. If following a transfer of shares a shareholder wishes to vote at or participate in a shareholders' meeting, such shareholder must file a share registration form in order to be registered in Addex' share register with voting rights. Failing such registration, a shareholder may not vote at or participate in a shareholders' meeting. The shares in the form of American Depository Shares or ADSs are held by Citibank acting as depositary and voted at the shareholders' meeting according to the instructions received from the ADS holders.

A purchaser of shares will be recorded in Addex' share register as a shareholder with voting rights if the purchaser discloses its name, citizenship or registered office and address and gives a declaration that it has acquired the shares in its own name and for its own account.

Article 5 of the Articles provides that a person or entity that does not explicitly state in its registration request that it will hold the shares for its own account (Nominee) may be entered as a shareholder in the share register with voting rights for shares up to a maximum of 5% of the share capital as set forth in the commercial register. Shares held by a Nominee that exceed this limit are only registered in the share register with voting rights if such Nominee discloses the name, address and shareholding of any person or legal entity for whose account it is holding 1% or more of the share capital as set forth in the commercial register. The limit of 1% shall apply correspondingly to Nominees who are related to one another through capital ownership or voting rights or have a common management or are otherwise interrelated. A share being indivisible, hence only one representative of each share will be recognized. Furthermore, shares may only be pledged in favor of the bank that administers the bank entries of such shares for the account of the pledging shareholders. If the registration of shareholdings with voting rights was effected based on false information, the Board may

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cancel such registration with retroactive effect. There are no further rules in the Articles for granting exceptions and no exceptions were granted in 2020. The Articles do not contain any provisions on the procedure and conditions for cancelling privileges and limitations on transferability.

Convertible bonds and options

As of December 31, 2020, we had no convertible or exchangeable bonds or loans outstanding. As of December 31, 2020, we had a total of 13,034,108 options that primarily include 6,768,460 Employee Share Option Plan (ESOP), 5,866,898 warrants and 198,750 Equity Sharing Certificates (ESCs). The ESOP and ESCs outstanding, are granted to our non-Directors, Executive Management, employees or consultants. They vest over a four-year period and have a 1:1 subscription ratio, from five to ten-year expiration term and an exercise price between CHF 1.00 to CHF 3.00. The warrants outstanding, which have been granted in connection with the capital increase of March 28, 2018. For each new share, the investors received 0.45 of a warrant. Each warrant entitles the investor to subscribe (which may be exercised without any specific conditions) to one registered share at a price of CHF 3.43 during a seven year period. For information on equity incentive plans for non-executive Directors, executive management and employees, refer to note 14 of the audited consolidated financial statements incorporated by reference into this registration statement.

Stock Exchange Listing

Our ADSs have been listed on Nasdaq, under the symbol "ADXN" since January 29, 2020 and our shares have been listed on SIX under the ticker symbol "ADXN" since May 21, 2007.

Registrar of Shares, Depositary for ADSs

Our share register is maintained by ShareCommService AG. The share register reflects only record owners of our shares. Holders of ADSs representing our shares will not be treated as our shareholders and their names will therefore not be entered in our share register. Citibank, N.A. acts as the depositary for the ADSs representing our shares and the custodian for shares represented by ADSs is Citibank Zurich. Holders of ADSs representing our shares have a right to receive the shares underlying such ADSs. For discussion on ADSs representing our shares and rights of ADS holders, see the section entitled "Description of American Depositary Shares" in this prospectus.

Notification and Disclosure of Substantial Share Interests

Under the applicable provisions of the Swiss Federal Act on Financial Market Infrastructures and Market Conduct in Securities and Derivatives Trading of 2015, or the Financial Market Infrastructure Act ("FMIA"), persons who directly, indirectly or in concert with other parties acquire or dispose of our shares, purchase rights or obligations relating to our shares (the "Purchase Positions") or sale rights or obligations relating to our shares (the "Sale Positions"), and thereby, directly, indirectly or in concert with other parties reach, exceed or fall below a threshold of 3%, 5%, 10%, 15%, 20%, 25%, 33¹/3%, 50% or 66²/3% of our voting rights (whether exercisable or not) must notify us and the Disclosure Office of the SIX of such acquisition or disposal in writing within four trading days. Within two trading days of the receipt of such notification, we must publish such information via the SIX's electronic publishing platform. For purposes of calculating whether a threshold has been reached or crossed, shares and Purchase Positions, on the one hand, and Sale Positions, on the other hand, may not be netted. Rather, the shares and Purchase Positions and the Sale Positions must be accounted for separately and may each trigger disclosure obligations if the respective positions reach, exceed or fall below one of the thresholds. In addition, actual share ownership must be reported separately if it reaches, exceeds or falls below one of the thresholds.

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Pursuant to Article 663c of the CO, Swiss corporations whose shares are listed on a stock exchange must disclose their significant shareholders and their shareholdings in the notes to their balance sheet, where this information is known or ought to be known. Significant shareholders are defined as shareholders and groups of shareholders linked through voting rights who hold more than 5% of all voting rights.

Selective "opting-out"

The shareholders have resolved to include in our Articles of Association an opting-out provision exempting Growth Equity Opportunities Fund IV, LLC, c/o New Enterprise Associates, 1954 Greenspring Drive, Suite 600, Timonium, MD 21093, and New Leaf Biopharma Opportunities I, L.P., 7 Times Square, Suite 3502, New York, NY 10036, United Stated, in each case including their direct or indirect partners or shareholders as well as any other entity or person (whether incorporated or not) that alone or together with others controls or otherwise holds any interest in them, from the duty to make a mandatory tender offer pursuant to Art. 135 of the Swiss Financial Markets Infrastructure Act (FMIA) based on Art. 125 para. 3 FMIA. The opting-out clause is limited in time and will expire on March 21, 2023, with effect for any crossing of the threshold pursuant to Art. 135 FMIA which occurs thereafter. As a result, until expiration of the opting-out clause, when exceeding the threshold of 33¹/3% of the voting rights (whether exercisable or not) of us, the investors mentioned in the opting-out clause are, when acting alone or in concert pursuant to Art. 135 FMIA, exempted from the duty pursuant to Art. 135 FMIA to make a mandatory tender offer to the other shareholders. Different from other companies listed in Switzerland which have no opting-out clause, upon reaching the threshold of 33¹/3% of our voting rights (whether exercisable or not) by the investors mentioned in the opting-out clause, the shareholders will neither benefit from the option to sell their shares in a mandatory tender offer nor from minority shareholder protection rules related to such mandatory tender offers.

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COMPARISON OF SWISS LAW AND DELAWARE LAW

The Swiss laws applicable to Swiss corporations and their shareholders differ from laws applicable to U.S. corporations and their shareholders. The following table summarizes significant differences in shareholder rights between the provisions of the Swiss Code of Obligations (Code suisse des obligations) and the Swiss Ordinance against excessive compensation in listed stock corporations applicable to our company and the Delaware General Corporation Law applicable to companies incorporated in Delaware and their shareholders. Please note that this is only a general summary of certain provisions applicable to companies in Delaware. Certain Delaware companies may be permitted to exclude certain of the provisions summarized below in their charter documents.

DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

Mergers and similar arrangements
Under the Delaware General Corporation Law, with certain exceptions, a merger, consolidation, sale, lease or transfer of all or substantially all of the assets of a corporation must be approved by the board of directors and a majority of the outstanding shares entitled to vote thereon. A shareholder of a Delaware corporation participating in certain major corporate transactions may, under certain circumstances, be entitled to appraisal rights pursuant to which such shareholder may receive cash in the amount of the fair value of the shares held by such shareholder (as determined by a court) in lieu of the consideration such shareholder would otherwise receive in the transaction. The Delaware General Corporation Law also provides that a parent corporation, by resolution of its board of directors, may merge with any subsidiary, of which it owns at least 90.0% of each class of capital stock without a vote by the shareholders of such subsidiary. Upon any such merger, dissenting shareholders of the subsidiary would have appraisal rights.		Under Swiss law, with certain exceptions, a merger or a division of the corporation or a sale of all or substantially all of the assets of a corporation must be approved by two-thirds of the shares represented at the relevant general meeting of shareholders as well as the absolute majority of the par value of the shares represented at such shareholders' meeting. The articles of association may increase the voting threshold. A shareholder of a Swiss corporation participating in a statutory merger or demerger pursuant to the Swiss Merger Act can file an appraisal right lawsuit against the surviving company. As a result, if the consideration is deemed "inadequate," such shareholder may, in addition to the consideration (be it in shares or in cash) receive an additional amount to ensure that such shareholder receives the fair value of the shares held by such shareholder. Swiss law also provides that a parent corporation, by resolution of its board of directors, may merge with any subsidiary, of which it owns at least 90.0% of the voting rights without a vote by shareholders of such subsidiary, if the shareholders of the subsidiary are offered the payment of the fair value in cash as an alternative to shares.

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

Shareholders' suits
Class actions and derivative actions generally are available to shareholders of a Delaware corporation for, among other things, breach of fiduciary duty, corporate waste and actions not taken in accordance with applicable law. In such actions, the court has discretion to permit the winning party to recover attorneys' fees incurred in connection with such action.		Class actions and derivative actions as such are not available under Swiss law. Nevertheless, certain actions may, to a limited extent, have a similar effect. An appraisal lawsuit won by a shareholder can be acted upon by any person who has the same legal status as the claimant. Also, a shareholder is entitled to bring suit against directors for breach of, among other things, their fiduciary duties and claim the payment of damages. However, unless the company is subject to bankruptcy proceedings, or if the relevant shareholder can demonstrate having suffered a loss in a personal capacity, a shareholder will only be allowed to ask for payment of damages to the corporation. Likewise, an appraisal lawsuit won by a shareholder may indirectly compensate all shareholders. Under Swiss law, the winning party is generally entitled to recover a limited amount of attorneys' fees incurred in connection with such action, provided, however, that the court has discretion to permit the shareholder whose claim has been dismissed to recover attorneys' fees incurred to the extent he acted in good faith.
Shareholder vote on board and management compensation
Under the Delaware General Corporation Law, the board of directors has the authority to fix the compensation of directors, unless otherwise restricted by the certificate of incorporation or bylaws.		Pursuant to the Swiss Ordinance against excessive compensation in listed stock corporations, the general meeting of shareholders has the non-transferable right, amongst others, to have a binding vote each year on the compensation due to the board of directors, executive management and advisory boards.
Annual vote on board renewal
Unless directors are elected by written consent in lieu of an annual meeting, directors are elected in an annual meeting of stockholders on a date and at a time designated by or in the manner provided in the bylaws. Re-election is possible. Classified boards are permitted.		The general meeting of shareholders elects annually (i.e. for a term until the end of the following annual general meeting) the members of the board of directors, the chairman of the board and the members of the compensation committee individually for a term of office of one year. Re-election is possible.

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

Indemnification of directors and executive management and limitation of liability
The Delaware General Corporation Law provides that a certificate of incorporation may contain a provision eliminating or limiting the personal liability of directors (but not other controlling persons) of the corporation for monetary damages for breach of a fiduciary duty as a director, except no provision in the certificate of incorporation may eliminate or limit the liability of a director for: • any breach of a director's duty of loyalty to the corporation or its shareholders; • acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law; • statutory liability for unlawful payment of dividends or unlawful stock purchase or redemption; or • any transaction from which the director derived an improper personal benefit. A Delaware corporation may indemnify any person who was or is a party or is threatened to be made a party to any proceeding, other than an action by or on behalf of the corporation, because the person is or was a director or officer, against liability incurred in connection with the proceeding if the director or officer acted in good faith and in a manner reasonably believed to be in, or not opposed to, the best interests of the corporation; and the director or officer, with respect to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful.		Under Swiss corporate law, an indemnification of a director or member of the executive management in relation to potential personal liability is not effective to the extent the director or member of the executive management intentionally or negligently violated his or her corporate duties towards the corporation (certain views advocate that at least a grossly negligent violation is required to exclude the indemnification). Furthermore, the general meeting of shareholders may discharge (release) the directors and members of the executive management from liability for their conduct to the extent the respective facts are known to shareholders. Such discharge is effective only with respect to claims of the company and of those shareholders who approved the discharge or who have since acquired their shares in full knowledge of the discharge. Most violations of corporate law are regarded as violations of duties towards the corporation rather than towards the shareholders. In addition, indemnification of other controlling persons is not permitted under Swiss corporate law, including shareholders of the corporation. The articles of association of a Swiss corporation may also set forth that the corporation shall indemnify and hold harmless, to the extent permitted by the law, the directors and executive managers out of assets of the corporation against threatened, pending or completed actions. Also, a corporation may enter into and pay for directors' and officers' liability insurance which typically covers negligent acts as well.
Unless ordered by a court, any foregoing indemnification is subject to a determination that the director or officer has met the applicable standard of conduct:
• by a majority vote of the directors who are not parties to the proceeding, even though less than a quorum;
• by a committee of directors designated by a majority vote of the eligible directors, even though less than a quorum;
• by independent legal counsel in a written opinion if there are no eligible directors, or if the eligible directors so direct; or

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

• by the shareholders.
Moreover, a Delaware corporation may not indemnify a director or officer in connection with any proceeding in which the director or officer has been adjudged to be liable to the corporation unless and only to the extent that the court determines that, despite the adjudication of liability but in view of all the circumstances of the case, the director or officer is fairly and reasonably entitled to indemnity for those expenses which the court deems proper.
Directors' fiduciary duties
A director of a Delaware corporation has a fiduciary duty to the corporation and its shareholders. This duty has two components: • the duty of care; and • the duty of loyalty. The duty of care requires that a director act in good faith, with the care that an ordinarily prudent person would exercise under similar circumstances. Under this duty, a director must inform himself of, and disclose to shareholders, all material information reasonably available regarding a significant transaction. The duty of loyalty requires that a director act in a manner he reasonably believes to be in the best interests of the corporation. He must not use his corporate position for personal gain or advantage. This duty prohibits self-dealing by a director and mandates that the best interest of the corporation and its shareholders take precedence over any interest possessed by a director, officer or controlling shareholder and not shared by the shareholders generally. In general, actions of a director are presumed to have been made on an informed basis, in good faith and in the honest belief that the action taken was in the best interests of the corporation. However, this presumption may be rebutted by evidence of a breach of one of the fiduciary duties. Should such evidence be presented concerning a transaction by a director, a director must prove the procedural fairness of the transaction, and that the transaction was of fair value to the corporation.		The board of directors of a Swiss corporation manages the business of the corporation, unless responsibility for such management has been duly delegated to the executive management based on organizational rules. However, there are several non-transferable duties of the board of directors: • the overall management of the corporation and the issuing of all necessary directives; • determination of the corporation's organization; • the organization of the accounting, financial control and financial planning systems as required for management of the corporation; • the appointment and dismissal of persons entrusted with managing and representing the corporation; • overall supervision of the persons entrusted with managing the corporation, in particular with regard to compliance with the law, articles of association, operational regulations and directives; • compilation of the annual report, preparation for the general meeting of the shareholders, the compensation report and implementation of its resolutions; and • notification of the court in the event that the company is over-indebted. A director of a Swiss corporation has a fiduciary duty to the corporation only. This duty has two components: • the duty of care; and • the duty of loyalty.

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

		The duty of care requires that a director act in good faith, with the care that an ordinarily prudent director would exercise under similar circumstances. The duty of loyalty requires that a director safeguard the interests of the corporation and requires that directors act in the interest of the corporation and, if necessarily, put aside their own interests. If there is a risk of a conflict of interest, the board of directors must take appropriate measures to ensure that the interests of the company are duly taken into account. The burden of proof for a violation of these duties is with the corporation or with the shareholder bringing a suit against the director. Directors also have an obligation to treat shareholders that are in similar situations equally.
Shareholder action by written consent
A Delaware corporation may, in its certificate of incorporation, eliminate the right of shareholders to act by written consent.		Shareholders of a Swiss corporation may only exercise their voting rights in a general meeting of shareholders and may not act by written consents.
Shareholder proposals
A shareholder of a Delaware corporation has the right to put any proposal before the annual meeting of shareholders, provided it complies with the notice provisions in the governing documents. A special meeting may be called by the board of directors or any other person authorized to do so in the governing documents, but shareholders may be precluded from calling special meetings.		At any general meeting of shareholders any shareholder may put proposals to the meeting if the proposal is part of an agenda item. No resolution may be taken on proposals relating to the agenda items that were not duly notified. Unless the articles of association provide for a lower threshold or for additional shareholders' rights: • one or several shareholders representing 10.0% of the share capital may ask that a general meeting of shareholders be called for specific agenda items and specific proposals; and • one or several shareholders representing 10.0% of the share capital or CHF 1.0 million of nominal share capital, whichever is lower may ask that an agenda item including a specific proposal be put on the agenda for a regularly scheduled general meeting of shareholders, provided such request is made with appropriate notice.

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

		Any shareholder can propose candidates for election as directors or make other proposals within the scope of an agenda item without prior written notice.
		In addition, any shareholder is entitled, at a general meeting of shareholders and without advance notice, to (1) request information from the Board on the affairs of the company (note, however, that the right to obtain such information is limited), (2) request information from the auditors on the methods and results of their audit, (3) request that the general meeting of shareholders resolve to convene an extraordinary general meeting and (4) request, under certain circumstances and subject to certain conditions, that the general meeting of shareholders resolve a special audit.
Cumulative voting
Under the Delaware General Corporation Law, cumulative voting for elections of directors is not permitted unless the corporation's certificate of incorporation provides for it.		Cumulative voting is not permitted under Swiss corporate law. Pursuant to Swiss law, shareholders can vote for each proposed candidate, but they are not allowed to cumulate their votes for single candidates. An annual individual election of all members of the board of directors for a term of office of one year (i.e. until the end of the following annual general meeting) is mandatory for listed companies.
Removal of directors
A Delaware corporation with a classified board may be removed only for cause with the approval of a majority of the outstanding shares entitled to vote, unless the certificate of incorporation provides otherwise.		A Swiss corporation may remove, with or without cause, any director at any time with a resolution passed by an absolute majority of the shares represented at a general meeting of shareholders concerned. The articles of association may require the approval by a qualified majority of the shares represented at a meeting for the removal of a director. Our articles of association require that a shareholder resolution to remove an acting director be passed with an absolute majority of the shares represented.

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

Transactions with interested shareholders
The Delaware General Corporation Law generally prohibits a Delaware corporation from engaging in certain business combinations with an "interested shareholder" for three years following the date that such person becomes an interested shareholder. An interested shareholder generally is a person or group who or which owns or owned 15.0% or more of the corporation's outstanding voting stock within the past three years.		No such specific rule applies to a Swiss corporation.
Dissolution; Winding up
Unless the board of directors of a Delaware corporation approves the proposal to dissolve, dissolution must be approved by shareholders holding 100.0% of the total voting power of the corporation. Only if the dissolution is initiated by the board of directors may it be approved by a simple majority of the corporation's outstanding shares. Delaware law allows a Delaware corporation to include in its certificate of incorporation a supermajority voting requirement in connection with dissolutions initiated by the board.		A dissolution and winding up of a Swiss corporation requires the approval by two-thirds of the shares represented as well as the absolute majority of the par value of the shares represented at a general meeting of shareholders passing a resolution on such dissolution and winding up. The articles of association may increase the voting thresholds required for such a resolution.
Variation of rights of shares
A Delaware corporation may vary the rights of a class of shares with the approval of a majority of the outstanding shares of such class, unless the certificate of incorporation provides otherwise.		The general meeting of shareholders of a Swiss corporation may resolve that preference shares be issued or that existing shares be converted into preference shares with a resolution passed by a majority of the shares represented at the general meeting of shareholders. Where a company has issued preference shares, further preference shares conferring preferential rights over the existing preference shares may be issued only with the consent of both a special meeting of the adversely affected holders of the existing preference shares and of a general meeting of all shareholders, unless otherwise provided in the articles of association. The issuance of shares that are granted more voting power requires the approval by two-thirds of the shares represented as well as the absolute majority of the par value of the shares represented at the relevant general meeting of shareholders.
		Shares with preferential voting rights are not regarded as preference shares for these purposes.

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

Amendment of governing documents
A Delaware corporation's governing documents may be amended with the approval of a majority of the outstanding shares entitled to vote, unless the certificate of incorporation provides otherwise.		The articles of association of a Swiss corporation may be amended with a resolution passed by an absolute majority of the shares represented at such meeting, unless otherwise provided in the articles of association. There are a number of resolutions, such as an amendment of the stated purpose of the corporation and the introduction of authorized and conditional capital, that require the approval by two-thirds of the votes and an absolute majority of the par value of the shares represented at a shareholders' meeting. The articles of association may increase the voting thresholds.
Inspection of books and records
Shareholders of a Delaware corporation, upon written demand under oath stating the purpose thereof, have the right during the usual hours for business to inspect for any proper purpose, and to obtain copies of list(s) of shareholders and other books and records of the corporation and its subsidiaries, if any, to the extent the books and records of such subsidiaries are available to the corporation.		Shareholders of a Swiss corporation may only inspect books and records if the general meeting of shareholders or the board of directors approved such inspection and only if confidential information possessed by a corporation is protected. A shareholder is only entitled to receive information to the extent required to exercise such shareholders' rights, subject to the interests of the corporation. The right to inspect the share register is limited to the right to inspect that shareholder's own entry in the share register.
Payment of dividends
The board of directors may approve a dividend without shareholder approval. Subject to any restrictions contained in its certificate of incorporation, the board may declare and pay dividends upon the shares of its capital stock either: • out of its surplus; or • in case there is no such surplus, out of its net profits for the fiscal year in which the dividend is declared or the preceding fiscal year. Stockholder approval is required to authorize capital stock in excess of that provided in the charter. Directors may issue authorized shares without stockholder approval.		Dividend payments are subject to the approval of the general meeting of shareholders. The board of directors may propose to shareholders that a dividend shall be paid but cannot itself authorize the distribution. Payments out of the company's stated share capital (in other words, the aggregate par value of the company's registered share capital) in the form of dividends are not allowed; payments out of stated share capital may be made by way of a capital reduction only. Dividends may be paid only from the profits from the previous business year or from the profits brought forward from the previous business years or if the company has distributable reserves, each as will be presented on the company's audited annual stand-alone balance sheet and after allocations to reserves required by Swiss law and its articles of association have been deducted. The dividend may be determined only after the allocations to reserves required by the law and the articles of association have been made.

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DELAWARE CORPORATE LAW		SWISS CORPORATE LAW

Creation and issuance of new shares
All creation of shares require the board of directors to adopt a resolution or resolutions, pursuant to authority expressly vested in the board of directors by the provisions of the company's certificate of incorporation.		All creation of shares require a shareholders' resolution. The creation of authorized or conditional share capital requires at least two-thirds of the voting rights represented at the general meeting of shareholders and an absolute majority of the nominal value of shares represented at such meeting. The board of directors may issue shares out of the authorized share capital during a period of up to two years. Shares are created and issued out of conditional share capital through the exercise of options or of conversion rights that the board of director may grant in relation to, e.g., debt instruments or employees.
Rights plans / poison pills
		Under Swiss corporation law, shareholders have pre-emptive rights to subscribe for new issuances of shares. Under certain circumstances, shareholders may authorize the board of directors to limit or withdraw pre-emptive rights or advance subscription rights in certain circumstances. However, limitation or withdrawal of shareholders' pre-emptive rights can only be decided for valid reasons. Preventing a particular shareholder to exercise influence over the company is generally believed not to be a valid reason to limit or withdraw shareholders' pre-emptive rights.

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DESCRIPTION OF AMERICAN DEPOSITARY SHARES

American Depositary Shares

Citibank, N.A., or Citibank, acts as the depositary for the ADSs representing our shares. Citibank's depositary offices are located at 388 Greenwich Street, New York, New York 10013. ADSs represent ownership interests in securities that are on deposit with the depositary. ADSs may be represented by certificates that are commonly known as American Depositary Receipts, or ADRs. The depositary typically appoints a custodian to safekeep the securities on deposit. In this case, the custodian is Citibank Zurich, located at 25 Seestrasee, 8021 Zurich, Switzerland.

We have appointed Citibank as depositary pursuant to a deposit agreement. The form of the deposit agreement is on file with the SEC under cover of a Registration Statement on Form F-6. You may obtain a copy of the deposit agreement from the SEC's website (www.sec.gov). Please refer to Registration Number 333-235561 when retrieving such copy.

We are providing you with a summary description of the material terms of the ADSs and of your material rights as an owner of ADSs. Please remember that summaries by their nature lack the precision of the information summarized and that the rights and obligations of an owner of ADSs will be determined by reference to the terms of the deposit agreement and not by this summary. We urge you to review the deposit agreement in its entirety. The portions of this summary description that are italicized describe matters that may be relevant to the ownership of ADSs but that may not be contained in the deposit agreement.

Each ADS represents the right to receive, and to exercise the beneficial ownership interests in, six shares that are on deposit with the depositary and/or custodian. An ADS also represents the right to receive, and to exercise the beneficial interests in, any other property received by the depositary or the custodian on behalf of the owner of the ADS but that has not been distributed to the owners of ADSs because of legal restrictions or practical considerations. We and the depositary may agree to change the ADS-to-share ratio by amending the deposit agreement. This amendment may give rise to, or change, the depositary fees payable by ADS owners. The custodian, the depositary and their respective nominees will hold all deposited property for the benefit of the holders and beneficial owners of ADSs. The deposited property does not constitute the proprietary assets of the depositary, the custodian or their nominees. Beneficial ownership in the deposited property will under the terms of the deposit agreement be vested in the beneficial owners of the ADSs. The depositary, the custodian and their respective nominees will be the record holders of the deposited property represented by the ADSs for the benefit of the holders and beneficial owners of the corresponding ADSs. A beneficial owner of ADSs may or may not be the holder of ADSs. Beneficial owners of ADSs will be able to receive, and to exercise beneficial ownership interests in, the deposited property only through the registered holders of the ADSs, the registered holders of the ADSs (on behalf of the applicable ADS owners) only through the depositary, and the depositary (on behalf of the owners of the corresponding ADSs) directly, or indirectly, through the custodian or their respective nominees, in each case upon the terms of the deposit agreement.

If you become an owner of ADSs, you will become a party to the deposit agreement and therefore will be bound to its terms and to the terms of any ADR that represents your ADSs. The deposit agreement and the ADR specify our rights and obligations as well as your rights and obligations as owner of ADSs and those of the depositary. As an ADS holder you appoint the depositary to act on your behalf in certain circumstances. The deposit agreement, the ADRs and ADSs are governed by New York law. However, our obligations to the holders of shares will continue to be governed by the laws of Switzerland, which may be different from the laws in the United States.

In addition, applicable laws and regulations may require you to satisfy reporting requirements and obtain regulatory approvals in certain circumstances. You are solely responsible for complying with such

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reporting requirements and obtaining such approvals. Neither the depositary, the custodian, us or any of their or our respective agents or affiliates shall be required to take any actions whatsoever on your behalf to satisfy such reporting requirements or obtain such regulatory approvals under applicable laws and regulations.

As an owner of ADSs, we will not treat you as one of our shareholders and you will not have direct shareholder rights. The depositary will hold on your behalf the shareholder rights attached to the shares underlying your ADSs. As an owner of ADSs you will be able to exercise the shareholders rights for the shares represented by your ADSs through the depositary only to the extent contemplated in the deposit agreement. To exercise any shareholder rights not contemplated in the deposit agreement you will, as an ADS owner, need to arrange for the cancellation of your ADSs and become a direct shareholder.

The manner in which you own the ADSs (e.g., in a brokerage account versus as a registered holder, or as a holder of certificated versus uncertificated ADSs) may affect your rights and obligations, and the manner in which, and extent to which, the depositary's services are made available to you.

As an owner of ADSs, you may hold your ADSs either by means of an ADR registered in your name, through a brokerage or safekeeping account, or through an account established by the depositary in your name reflecting the registration of uncertificated ADSs directly on the books of the depositary (commonly referred to as the direct registration system or DRS). The direct registration system reflects the uncertificated (book-entry) registration of ownership of ADSs by the depositary. Under the direct registration system, ownership of ADSs is evidenced by periodic statements issued by the depositary to the holders of the ADSs. The direct registration system includes automated transfers between the depositary and The Depository Trust Company, or DTC, the central book-entry clearing and settlement system for equity securities in the United States. If you decide to hold your ADSs through your brokerage or safekeeping account, you must rely on the procedures of your broker or bank to assert your rights as ADS owner. Banks and brokers typically hold securities such as the ADSs through clearing and settlement systems such as DTC. The procedures of such clearing and settlement systems may limit your ability to exercise your rights as an owner of ADSs. Please consult with your broker or bank if you have any questions concerning these limitations and procedures. All ADSs held through DTC will be registered in the name of a nominee of DTC. This summary description assumes you have opted to own the ADSs directly by means of an ADS registered in your name and, as such, we will refer to you as the "holder." When we refer to "you," we assume the reader owns ADSs and will own ADSs at the relevant time.

The registration of the shares in the name of the depositary or the custodian shall, to the maximum extent permitted by applicable law, vest in the depositary or the custodian the record ownership in the applicable shares with the beneficial ownership rights and interests in such shares being at all times vested with the beneficial owners of the ADSs representing the shares. The depositary or the custodian shall at all times be entitled to exercise the beneficial ownership rights in all deposited property, in each case only on behalf of the holders and beneficial owners of the ADSs representing the deposited property.

Dividends and Other Distributions

As a holder of ADSs, you generally have the right to receive the distributions we make on the securities deposited with the custodian. Your receipt of these distributions may be limited, however, by practical considerations and legal limitations. Holders of ADSs will receive such distributions under the terms of the deposit agreement in proportion to the number of ADSs held as of the specified record date, after deduction the applicable fees, taxes and expenses.

Distributions of Cash

Whenever we make a cash distribution for the securities on deposit with the custodian, we will deposit the funds with the custodian. Upon receipt of confirmation of the deposit of the requisite

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funds, the depositary will arrange for the funds received in a currency other than U.S. dollars to be converted into U.S. dollars and for the distribution of the U.S. dollars to the holders, subject to the laws and regulations of Switzerland. The conversion into U.S. dollars will take place only if practicable and if the U.S. dollars are transferable to the United States. The depositary will apply the same method for distributing the proceeds of the sale of any property (such as undistributed rights) held by the custodian in respect of securities on deposit.

The distribution of cash will be made net of the fees, expenses, taxes and governmental charges payable by holders under the terms of the deposit agreement. The depositary will hold any cash amounts it is unable to distribute in a non-interest bearing account for the benefit of the applicable holders and beneficial owners of ADSs until the distribution can be effected or the funds that the depositary holds must be escheated as unclaimed property in accordance with the laws of the relevant states of the United States.

Distributions of Shares

Whenever we make a free distribution of shares for the securities on deposit with the custodian, we will deposit the applicable number of shares with the custodian. Upon receipt of confirmation of such deposit, the depositary will either distribute to holders new ADSs representing the shares deposited or modify the ADS-to-shares ratio, in which case each ADS you hold will represent rights and interests in the additional shares so deposited. Only whole new ADSs will be distributed. Fractional entitlements will be sold and the proceeds of such sale will be distributed as in the case of a cash distribution.

The distribution of new ADSs or the modification of the ADS-to-shares ratio upon a distribution of shares will be made net of the fees, expenses, taxes and governmental charges payable by holders under the terms of the deposit agreement. In order to pay such taxes or governmental charges, the depositary may sell all or a portion of the new shares so distributed.

No such distribution of new ADSs will be made if it would violate a law (e.g., the U.S. securities laws) or if it is not operationally practicable. If the depositary does not distribute new ADSs as described above, it may sell the shares received upon the terms described in the deposit agreement and will distribute the proceeds of the sale as in the case of a distribution of cash.

Distributions of Rights

Whenever we intend to distribute rights to subscribe for additional shares, we will give prior notice to the depositary and we will assist the depositary in determining whether it is lawful and reasonably practicable to distribute rights to subscribe for additional ADSs to holders.

The depositary will establish procedures to distribute rights to purchase additional ADSs to holders and to enable such holders to exercise such rights if it is lawful and reasonably practicable to make the rights available to holders of ADSs, and if we provide all of the documentation contemplated in the deposit agreement (such as opinions to address the lawfulness of the transaction). You may have to pay fees, expenses, taxes and other governmental charges to subscribe for the new ADSs upon the exercise of your rights. The depositary is not obligated to establish procedures to facilitate the distribution and exercise by holders of rights to purchase new shares other than in the form of ADSs.

The depositary will not distribute the rights to you if:

•: we do not timely request that the rights be distributed to you or we request that the rights not be distributed to you; or
•: we fail to deliver satisfactory documents to the depositary; or
•: it is not reasonably practicable to distribute the rights.

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The depositary will sell the rights that are not exercised or not distributed if such sale is lawful and reasonably practicable. The proceeds of such sale will be distributed to holders as in the case of a cash distribution. If the depositary is unable to sell the rights, it will allow the rights to lapse.

Elective Distributions

Whenever we intend to distribute a dividend payable at the election of shareholders either in cash or in additional shares, we will give prior notice thereof to the depositary and will indicate whether we wish the elective distribution to be made available to you. In such case, we will assist the depositary in determining whether such distribution is lawful and reasonably practicable.

The depositary will make the election available to you only if it is reasonably practicable and if we have provided all of the documentation contemplated in the deposit agreement. In such case, the depositary will establish procedures to enable you to elect to receive either cash or additional ADSs, in each case as described in the deposit agreement.

If the election is not made available to you, you will receive either cash or additional ADSs, depending on what a shareholder in Switzerland would receive upon failing to make an election, as more fully described in the deposit agreement.

Other Distributions

Whenever we intend to distribute property other than cash, shares or rights to purchase additional shares, we will notify the depositary in advance and will indicate whether we wish such distribution to be made to you. If so, we will assist the depositary in determining whether such distribution to holders is lawful and reasonably practicable.

If it is reasonably practicable to distribute such property to you and if we provide to the depositary all of the documentation contemplated in the deposit agreement, the depositary will distribute the property to the holders in a manner it deems practicable.

The distribution will be made net of fees, expenses, taxes and governmental charges payable by holders under the terms of the deposit agreement. In order to pay such taxes and governmental charges, the depositary may sell all or a portion of the property received.

The depositary will not distribute the property to you and will sell the property if:

•: we do not request that the property be distributed to you or if we request that the property not be distributed to you; or
•: we do not deliver satisfactory documents to the depositary; or
•: the depositary determines that all or a portion of the distribution to you is not reasonably practicable.

The proceeds of such a sale will be distributed to holders as in the case of a cash distribution.

Redemption

Whenever we decide to redeem any of the securities on deposit with the custodian, we will notify the depositary in advance. If it is practicable and if we provide all of the documentation contemplated in the deposit agreement, the depositary will provide notice of the redemption to the holders.

The custodian will be instructed to surrender the shares being redeemed against payment of the applicable redemption price. The depositary will convert into U.S. dollars upon the terms of the deposit agreement the redemption funds received in a currency other than U.S. dollars and will establish procedures to enable holders to receive the net proceeds from the redemption upon surrender of their

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ADSs to the depositary. You may have to pay fees, expenses, taxes and other governmental charges upon the redemption of your ADSs. If less than all ADSs are being redeemed, the ADSs to be retired will be selected by lot or on a pro rata basis, as the depositary may determine.

Changes Affecting Shares

The shares held on deposit for your ADSs may change from time to time. For example, there may be a change in nominal or par value, split-up, cancellation, consolidation or any other reclassification of such shares or a recapitalization, reorganization, merger, consolidation or sale of assets of the Company.

If any such change were to occur, your ADSs would, to the extent permitted by law and the deposit agreement, represent the right to receive the property received or exchanged in respect of the shares held on deposit. The depositary may in such circumstances deliver new ADSs to you, amend the deposit agreement, the ADRs and the applicable Registration Statement(s) on Form F-6, call for the exchange of your existing ADSs for new ADSs and take any other actions that are appropriate to reflect as to the ADSs the change affecting the shares. If the depositary may not lawfully distribute such property to you, the depositary may sell such property and distribute the net proceeds to you as in the case of a cash distribution.

Issuance of ADSs upon Deposit of Shares

The depositary will deliver ADSs if you or your broker deposits shares with the custodian. The depositary will deliver these ADSs to the person you indicate only after you pay any applicable issuance fees and any charges and taxes payable for the transfer of the shares to the custodian and provide such documentation as may be required pursuant to the deposit agreement. Your ability to deposit shares and receive ADSs may be limited by U.S. and Swiss legal considerations applicable at the time of deposit.

The issuance of ADSs may be delayed until the depositary or the custodian receives confirmation that all required approvals have been given and that the shares have been duly transferred to the custodian. The depositary will only issue ADSs in whole numbers.

When you make a deposit of shares, you will be responsible for transferring good and valid title to the depositary. As such, you will be deemed to represent and warrant that:

•: the shares are duly authorized, validly issued, fully paid, non-assessable and legally obtained;
•: all preemptive (and similar) rights, if any, with respect to such shares have been validly waived or exercised;
•: you are duly authorized to deposit the shares;
•: the shares presented for deposit are free and clear of any lien, encumbrance, security interest, charge, mortgage or adverse claim, and are not, and the ADSs issuable upon such deposit will not be, "restricted securities" (as defined in the deposit agreement); and
•: the shares presented for deposit have not been stripped of any rights or entitlements.

If any of the representations or warranties are incorrect in any way, we and the depositary may, at your cost and expense, take any and all actions necessary to correct the consequences of the misrepresentations.

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Transfer, Combination and Split Up of ADRs

As an ADR holder, you will be entitled to transfer, combine or split up your ADRs and the ADSs evidenced thereby. For transfers of ADRs, you will have to surrender the ADRs to be transferred to the depositary and also must:

•: ensure that the surrendered ADR is properly endorsed or otherwise in proper form for transfer;
•: provide such proof of identity and genuineness of signatures, and of such other matters contemplated in the deposit agreement, as the depositary deems appropriate;
•: comply with applicable laws and regulations, including regulations imposed by us and the depositary consistent with the deposit agreement, the ADSs, the ADR and applicable law;
•: provide any transfer stamps required by the State of New York or the United States; and
•: pay all applicable fees, charges, expenses, taxes and other government charges payable by ADR holders pursuant to the terms of the deposit agreement, upon the transfer of ADRs.

To have your ADRs either combined or split up, you must surrender the ADRs in question to the depositary with your request to have them combined or split up, and you must pay all applicable fees, charges and expenses payable by ADR holders, pursuant to the terms of the deposit agreement, upon a combination or split up of ADRs.

Withdrawal of Shares Upon Cancellation of ADSs

As a holder, you will be entitled to present your ADSs to the depositary for cancellation and then receive the corresponding number of underlying shares at the custodian's offices. Your ability to withdraw the shares held in respect of the ADSs may be limited by U.S. and Swiss considerations applicable at the time of withdrawal. In order to withdraw the shares represented by your ADSs, you will be required to pay to the depositary the fees for cancellation of ADSs and any charges and taxes payable upon the transfer of the shares. You assume the risk for delivery of all funds and securities upon withdrawal. Once canceled, the ADSs will not have any rights under the deposit agreement.

If you hold ADSs registered in your name, the depositary may ask you to provide proof of identity and genuineness of any signature and such other documents as the depositary may deem appropriate before it will cancel your ADSs. The withdrawal of the shares represented by your ADSs may be delayed until the depositary receives satisfactory evidence of compliance with all applicable laws and regulations. Please keep in mind that the depositary will only accept ADSs for cancellation that represent a whole number of securities on deposit.

You will have the right to withdraw the securities represented by your ADSs at any time except as a result of:

•: temporary delays that may arise because (i) the transfer books for the shares or ADSs are closed, or (ii) shares are immobilized on account of a shareholders' meeting or a payment of dividends;
•: obligations to pay fees, taxes and similar charges; or
•: restrictions imposed because of laws or regulations applicable to ADSs or the withdrawal of securities on deposit.

The deposit agreement may not be modified to impair your right to withdraw the securities represented by your ADSs except to comply with mandatory provisions of law.

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Voting Rights

As a holder, you generally have the right under the deposit agreement to instruct the depositary to exercise the voting rights for the shares represented by your ADSs. The voting rights of holders of shares are described in "Description of Share Capital and Articles of Association" in this prospectus.

At our request, the depositary will distribute to you any notice of shareholders' meeting received from us together with information explaining how to instruct the depositary to exercise the voting rights of the securities represented by ADSs. In lieu of distributing such materials, the depositary may distribute to holders of ADSs instructions on how to retrieve such materials upon request.

If the depositary timely receives voting instructions from a holder of ADSs, it will endeavor, as far as practicable, subject to the laws of Switzerland and of our Articles of Association or similar documents, to vote, or have its agents vote, the securities (in person or by proxy) represented by the holder's ADSs in accordance with such voting instructions.

Securities for which no voting instructions have been received will not be voted (except as otherwise contemplated in the deposit agreement). If the depositary timely receives voting instructions which fail to specify the manner in which the depositary is to vote the securities represented by such holder's ADSs, the depositary will deem such holder (unless otherwise specified in the notice distributed to holders or otherwise contemplated in the deposit agreement) to have instructed the depositary to take all steps necessary to enable the independent proxy holder, as elected by the shareholders of the Company, to vote in accordance with the written proposals or recommendations of the board of directors. Please note that the ability of the depositary bank to carry out voting instructions may be limited by practical and legal limitations and the terms of the securities on deposit. We cannot assure you that you will receive voting materials in time to enable you to return voting instructions to the depositary bank in a timely manner.

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Fees and Charges

As an ADS holder, you will be required to pay the following fees under the terms of the deposit agreement:

Service		Fee

Issuance of ADSs (e.g., an issuance of ADS upon a deposit of shares, upon a change in the ADS(s)-to-shares ratio, or for any other reason), excluding ADS issuances as a result of distributions of shares		Up to U.S. 5¢ per ADS issued
• Cancellation of ADSs (e.g., a cancellation of ADSs for delivery of deposited property, upon a change in the ADS(s)-to-shares ratio, or for any other reason)		Up to U.S. 5¢ per ADS cancelled
• Distribution of cash dividends or other cash distributions (e.g., upon a sale of rights and other entitlements)		Up to U.S. 5¢ per ADS held
• Distribution of ADSs pursuant to (i) stock dividends or other free stock distributions, or (ii) exercise of rights to purchase additional ADSs		Up to U.S. 5¢ per ADS held
• Distribution of securities other than ADSs or rights to purchase additional ADSs (e.g., upon a spin-off)		Up to U.S. 5¢ per ADS held
• ADS Services		Up to U.S. 5¢ per ADS held on the applicable record date(s) established by the depositary
• Registration of ADS transfers (e.g., upon a registration of the transfer of registered ownership of ADSs, upon a transfer of ADSs into DTC and vice versa, or for any other reason)		Up to U.S. 5¢ per ADS (or fraction thereof) transferred
• Conversion of ADSs of one series for ADSs of another series (e.g., upon conversion of Partial Entitlement ADSs for Full Entitlement ADSs, or upon conversion of Restricted ADSs (each as defined in the Deposit Agreement) into freely transferable ADSs, and vice versa).		Up to U.S. 5¢ per ADS (or fraction thereof) converted

As an ADS holder you will also be responsible to pay certain charges such as:

•: taxes (including applicable interest and penalties) and other governmental charges;
•: the registration fees as may from time to time be in effect for the registration of shares on the share register and applicable to transfers of shares to or from the name of the custodian, the depositary or any nominees upon the making of deposits and withdrawals, respectively;
•: certain cable, telex and facsimile transmission and delivery expenses;

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•: the fees, expenses, spreads, taxes and other charges of the depositary and/or service providers (which may be a division, branch or affiliate of the depositary) in the conversion of foreign currency;
•: the reasonable and customary out-of-pocket fees and expenses incurred by the depositary in connection with compliance with exchange control regulations and other regulatory requirements applicable to shares, ADSs and ADRs; and
•: the fees, charges, costs and expenses incurred by the depositary, the custodian, or any nominee in connection with the ADR program.

ADS fees and charges for (i) the issuance of ADSs, and (ii) the cancellation of ADSs are charged to the person for whom the ADSs are issued (in the case of ADS issuances) and to the person for whom ADSs are cancelled (in the case of ADS cancellations). In the case of ADSs issued by the depositary into DTC, the ADS issuance and cancellation fees and charges may be deducted from distributions made through DTC, and may be charged to the DTC participant(s) receiving the ADSs being issued or the DTC participant(s) holding the ADSs being cancelled, as the case may be, on behalf of the beneficial owner(s) and will be charged by the DTC participant(s) to the account of the applicable beneficial owner(s) in accordance with the procedures and practices of the DTC participants as in effect at the time. ADS fees and charges in respect of distributions and the ADS service fee are charged to the holders as of the applicable ADS record date. In the case of distributions of cash, the amount of the applicable ADS fees and charges is deducted from the funds being distributed. In the case of (i) distributions other than cash and (ii) the ADS service fee, holders as of the ADS record date will be invoiced for the amount of the ADS fees and charges and such ADS fees and charges may be deducted from distributions made to holders of ADSs. For ADSs held through DTC, the ADS fees and charges for distributions other than cash and the ADS service fee may be deducted from distributions made through DTC, and may be charged to the DTC participants in accordance with the procedures and practices prescribed by DTC and the DTC participants in turn charge the amount of such ADS fees and charges to the beneficial owners for whom they hold ADSs. In the case of (i) registration of ADS transfers, the ADS transfer fee will be payable by the ADS Holder whose ADSs are being transferred or by the person to whom the ADSs are transferred, and (ii) conversion of ADSs of one series for ADSs of another series, the ADS conversion fee will be payable by the Holder whose ADSs are converted or by the person to whom the converted ADSs are delivered.

In the event of refusal to pay the depositary fees, the depositary may, under the terms of the deposit agreement, refuse the requested service until payment is received or may set off the amount of the depositary fees from any distribution to be made to the ADS holder.

Note that the fees and charges you may be required to pay may vary over time and may be changed by us and by the depositary. You will receive prior notice of such changes. The depositary may reimburse us for certain expenses incurred by us in respect of the ADR program, by making available a portion of the ADS fees charged in respect of the ADR program or otherwise, upon such terms and conditions as we and the depositary agree from time to time.

Amendments and Termination

We may agree with the depositary to modify the deposit agreement at any time without your consent. We undertake to give holders 30 days' prior notice of any modifications that would materially prejudice any of their substantial rights under the deposit agreement. We will not consider to be materially prejudicial to your substantial rights any modifications or supplements that are reasonably necessary for the ADSs to be registered under the Securities Act or to be eligible for book-entry settlement, in each case without imposing or increasing the fees and charges you are required to pay. In addition, we may not be able to provide you with prior notice of any modifications or supplements that are required to accommodate compliance with applicable provisions of law.

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You will be bound by the modifications to the deposit agreement if you continue to hold your ADSs after the modifications to the deposit agreement become effective. The deposit agreement cannot be amended to prevent you from withdrawing the shares represented by your ADSs (except as permitted by law).

We have the right to direct the depositary to terminate the deposit agreement. Similarly, the depositary may in certain circumstances on its own initiative terminate the deposit agreement. In either case, the depositary must give notice to the holders at least 30 days before termination. Until termination, your rights under the deposit agreement will be unaffected.

Termination

After termination, the depositary will continue to collect distributions received (but will not distribute any such property until you request the cancellation of your ADSs) and may sell the securities held on deposit. After the sale, the depositary will hold the proceeds from such sale and any other funds then held for the holders of ADSs in a non-interest bearing account. At that point, the depositary will have no further obligations to ADS holders other than to account for the funds then held for the holders of ADSs still outstanding (after deduction of applicable fees, taxes and expenses).

In connection with any termination of the deposit agreement, the depositary may make available to owners of ADSs a means to withdraw the shares represented by their ADSs and to direct the depositary of such shares into an unsponsored American depositary share program established by the depositary. The ability to receive unsponsored American depositary shares upon termination of the deposit agreement would be subject to satisfaction of certain U.S. regulatory requirements applicable to the creation of unsponsored American depositary shares and the payment of applicable depositary fees.

Books of Depositary

The depositary will maintain ADS holder records at its depositary office. You may inspect such records at such office during regular business hours but solely for the purpose of communicating with other holders in the interest of business matters relating to the ADSs and the deposit agreement.

The depositary will maintain in New York facilities to record and process the issuance, cancellation, combination, split-up and transfer of ADSs. These facilities may be closed from time to time, to the extent not prohibited by law.

Limitations on Obligations and Liabilities

The deposit agreement limits our obligations and the depositary's obligations to you. Please note the following:

•: We and the depositary are obligated only to take the actions specifically stated in the deposit agreement without negligence or bad faith.
•: The depositary disclaims any liability for any failure to carry out voting instructions, for any manner in which a vote is cast or for the effect of any vote, provided it acts in good faith and in accordance with the terms of the deposit agreement.
•: The depositary disclaims any liability for any failure to determine the lawfulness or practicality of any action, for the content of any document forwarded to you on our behalf or for the accuracy of any translation of such a document, for the investment risks associated with investing in shares, for the validity or worth of the shares, for any tax consequences that result from the ownership of ADSs or other deposited property, for the credit-worthiness of any third party, for allowing any rights to lapse under the terms of the deposit agreement, for the timeliness of any

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of our notices or for our failure to give notice or for any act or omission of or information provided by DTC or any DTC participant.

•: The depositary shall not be liable for acts or omissions of any successor depositary in connection with any matter arising wholly after the resignation or removal of the depositary.
•: We and the depositary will not be obligated to perform any act that is inconsistent with the terms of the deposit agreement.
•: We and the depositary disclaim any liability if we or the depositary are prevented or forbidden from or subject to any civil or criminal penalty or restraint on account of, or delayed in, doing or performing any act or thing required by the terms of the deposit agreement, by reason of any provision, present or future law or regulation, including regulations of any stock exchange or by reason of present or future provisions of our Articles of Association, or any provision of or governing the securities on deposit, or by reason of any act of God or war or other circumstances beyond our or the depositary's control.
•: We and the depositary disclaim any liability by reason of any exercise of, or failure to exercise, any discretion provided for in the deposit agreement or in our Articles of Association or in any provisions of or governing the securities on deposit.
•: We and the depositary further disclaim any liability for any action or inaction in reliance on the advice or information received from legal counsel, accountants, any person presenting shares for deposit, any holder of ADSs or authorized representatives thereof, or any other person believed by either of us in good faith to be competent to give such advice or information.
•: We and the depositary also disclaim liability for the inability by any holder or beneficiary owner to benefit from any distribution, offering, right or other benefit that is made available to holders of shares but is not, under the terms of the deposit agreement, made available to you.
•: We and the depositary may rely without any liability upon any written notice, request or other document believed to be genuine and to have been signed or presented by the proper parties.
•: We and the depositary also disclaim liability for any consequential or punitive damages for any breach of the terms of the deposit agreement.
•: We and the depositary disclaim liability arising out of losses, liabilities, taxes, charges or expenses resulting from the manner in which a holder or beneficial owner of ADSs holds ADSs, including resulting from holding ADSs through a brokerage account.
•: No disclaimer of any Securities Act liability is intended by any provision of the deposit agreement.
•: Nothing in the deposit agreement gives rise to a partnership or joint venture, or establishes a fiduciary relationship, among us, the depositary and you as ADS holder.
•: Nothing in the deposit agreement precludes Citibank (or its affiliates) from engaging in transactions in which parties adverse to us or the ADS owners have interests, and nothing in the deposit agreement obligates Citibank to disclose those transactions, or any information obtained in the course of those transactions, to us or to the ADS owners, or to account for any payment received as part of those transactions.

Taxes

You will be responsible for the taxes and other governmental charges payable on the ADSs and the securities represented by the ADSs. We, the depositary and the custodian may deduct from any distribution the taxes and governmental charges payable by holders and may sell any and all property

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on deposit to pay the taxes and governmental charges payable by holders. You will be liable for any deficiency if the sale proceeds do not cover the taxes that are due.

The depositary may refuse to issue ADSs, to deliver, transfer, split and combine ADRs or to release securities on deposit until all taxes and charges are paid by the applicable holder. The depositary and the custodian may take reasonable administrative actions to obtain tax refunds and reduced tax withholding for any distributions on your behalf. However, you may be required to provide to the depositary and to the custodian proof of taxpayer status and residence and such other information as the depositary and the custodian may require to fulfill legal obligations. You are required to indemnify us, the depositary and the custodian for any claims with respect to taxes based on any tax benefit obtained for you.

Foreign Currency Conversion

The depositary will arrange for the conversion of all foreign currency received into U.S. dollars if such conversion is practical, and it will distribute the U.S. dollars in accordance with the terms of the deposit agreement. You may have to pay fees and expenses incurred in converting foreign currency, such as fees and expenses incurred in complying with currency exchange controls and other governmental requirements.

If the conversion of foreign currency is not practical or lawful, or if any required approvals are denied or not obtainable at a reasonable cost or within a reasonable period, the depositary may take any of the following actions in its discretion:

•: Convert the foreign currency to the extent practical and lawful and distribute the U.S. dollars to the holders for whom the conversion and distribution is lawful and practical.
•: Distribute the foreign currency to holders for whom the distribution is lawful and practical.
•: Hold the foreign currency (without liability for interest) for the applicable holders.

Governing Law / Waiver of Jury Trial

The deposit agreement and the ADRs and ADSs will be interpreted in accordance with the laws of the State of New York. The rights of holders of shares (including shares represented by ADSs) are governed by the laws of Switzerland. As an owner of ADSs, you irrevocably agree that any legal action arising out of the Deposit Agreement, the ADSs or the ADRs, involving the Company or the Depositary, may only be instituted in a state or federal court in the city of New York.

AS A PARTY TO THE DEPOSIT AGREEMENT, YOU IRREVOCABLY WAIVE, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, YOUR RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF THE DEPOSIT AGREEMENT OR THE ADRs AGAINST US AND/OR THE DEPOSITARY.

The deposit agreement provides that, to the extent permitted by law, ADS holders waive the right to a jury trial of any claim they may have against us or the depositary arising out of or relating to our shares, the ADSs or the deposit agreement, including any claim under U.S. federal securities laws. If we or the depositary opposed a jury trial demand based on the waiver, the court would determine whether the waiver was enforceable in the facts and circumstances of that case in accordance with applicable case law. However, you will not be deemed, by agreeing to the terms of the deposit agreement, to have waived our or the depositary's compliance with U.S. federal securities laws and the rules and regulations promulgated thereunder.

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PLAN OF DISTRIBUTION

Primary Offering

We may sell the securities in one or more of the following ways (or in any combination) from time to time:

•: through underwriters or dealers;
•: directly to a limited number of purchasers or to a single purchaser;
•: through agents; or
•: through any other method permitted by applicable law and described in the applicable prospectus supplement.

The distribution of securities may be carried out, from time to time, in one or more transactions, including:

•: block transactions and transactions on Nasdaq or any other organized market where the securities may be traded;
•: purchases by a broker-dealer as principal and resale by the broker-dealer for its own account pursuant to a prospectus supplement;
•: ordinary brokerage transactions and transactions in which a broker-dealer solicits purchasers;
•: sales "at the market" to or through a market maker or into an existing trading market, on an exchange or otherwise; or
•: sales in other ways not involving market makers or established trading markets, including direct sales to purchasers.

A prospectus supplement or supplements (and any related free writing prospectus that we may authorize to be provided to you) will describe the terms of the offering of the securities, including, to the extent applicable:

•: the name or names of any underwriters, dealers or agents;
•: the method of distribution;
•: the public offering price or purchase price and the proceeds to us from that sale;
•: the expenses of the offering;
•: any discounts or commissions to be allowed or paid to the underwriters, dealers or agents;
•: all other items constituting underwriting compensation and the discounts and commissions to be allowed or paid to dealers, if any; and
•: any other information regarding the distribution of the securities that we believe to be material.

Underwriters may offer and sell the securities at a fixed price or prices, which may be changed, or from time to time at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices. We may, from time to time, authorize agents acting on a best or reasonable efforts basis as our agents to solicit or receive offers to purchase the securities upon the terms and conditions as are set forth in the applicable prospectus supplement. In connection with the sale of securities, underwriters or agents may be deemed to have received compensation from us in the form of underwriting discounts or commissions and may also receive commissions from purchasers of securities for whom they may act as agent. Underwriters may sell securities to or through dealers, and dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agent.

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Underwriters, dealers and agents who participate in the distribution of securities and their controlling persons may be entitled, under agreements that may be entered into with us to indemnification by us against certain liabilities, including liabilities under the Securities Act, or to contribution with respect to payments that the underwriters, dealers or agents and their controlling persons may be required to make in respect of those liabilities.

We may also offer the shares to our existing shareholders through the granting of subscription rights on a pro rata basis, which may or may not be transferable. If in such a case not all underlying securities are subscribed for, we may then allocate the subscription rights directly to third parties or may engage the services of one or more underwriters, dealers or agents, including standby underwriters, to subscribe for the unsubscribed securities and to sell the corresponding shares to third parties.

Certain persons participating in an offering may engage in over-allotment, stabilizing transactions, short-covering transactions and penalty bids in accordance with Regulation M under the Exchange Act that stabilize, maintain or otherwise affect the price of the offered securities. If any such activities will occur, they will be described in the applicable prospectus supplement.

Secondary Offering

The registration statement of which this prospectus forms a part has been filed in part in respect of our obligations under a Registration Rights Agreement, dated March 22, 2018, concerning, among other things, an aggregate of 7,704,600 shares (including those issuable upon the exercise of warrants) currently held by the selling shareholder. Such shares are referred to collectively herein as the Registered Shares, and the holder of such shares is identified in this prospectus as the selling shareholder. Any Registered Shares offered and sold in the United States by the selling shareholder will be in the form of ADSs. The selling shareholder is also permitted to sell shares not represented by ADSs in private or offshore transactions, including on the SIX, which resales are not covered by this prospectus. The selling shareholder may, or may not, elect to sell Registered Shares represented by ADSs as and to the extent that it may individually determine. Such sales, if any, will be made through brokerage transactions on Nasdaq or other securities exchange in the United States at prevailing market prices.

The selling shareholder may dispose of all or a portion of the Registered Shares from time to time directly or through one or more underwriters, broker-dealers or agents. If ADSs representing our shares are sold through underwriters or broker-dealers, the selling shareholder will be responsible for any applicable underwriting discounts or commissions or agent's commissions. ADSs representing our shares may be sold on Nasdaq or any other national securities exchange or quotation service on which the securities may be listed or quoted at the time of disposition, in the over-the-counter market or in transactions otherwise than on these exchanges or systems or in the over-the-counter market and in one or more transactions at fixed prices, at prevailing market prices at the time of the disposition, at varying prices determined at the time of disposition, or at negotiated prices. These dispositions may be effected in transactions, which may involve crosses or block transactions. The selling shareholder may use any one or more of the following methods when disposing of shares:

•: ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;
•: block trades in which the broker-dealer will attempt to sell the shares as agent but may position and resell a portion of the block as principal to facilitate the transaction;
•: purchases by a broker-dealer as principal and resale by the broker-dealer for its account;
•: an exchange distribution in accordance with the rules of the applicable exchange;
•: privately negotiated transactions and offshore transactions;
•: settlement of short sales entered into after the effective date of the registration statement of which this prospectus is a part;

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•: broker-dealers may agree with the selling shareholder to sell a specified number of such shares at a stipulated price per share;
•: through the writing or settlement of options or other hedging transactions, whether such options are listed on an options exchange or otherwise;
•: a combination of any such methods of disposition; and
•: any other method permitted pursuant to applicable law.

The selling shareholder also may resell all or a portion of the Registered Shares in offshore transactions or open market transactions in reliance upon Regulation S under the Securities Act, if available, rather than under this prospectus, provided that they meet the criteria and conform to the requirements of those provisions.

Broker-dealers engaged by the selling shareholder may arrange for other broker-dealers to participate in dispositions. If the selling shareholder effects such transactions by selling ADSs representing our shares to or through underwriters, broker-dealers or agents, such underwriters, broker-dealers or agents may receive applicable commissions in the form of discounts, concessions or commissions from the selling shareholder or commissions from purchasers of ADSs representing our shares for whom they may act as agent or to whom they may sell as principal. Such commissions will be in amounts to be negotiated, but, except as set forth in a supplement to this prospectus, in the case of an agency transaction will not be in excess of a customary brokerage commission in compliance with FINRA Rule 2121 and Supplementary Material .01 and Supplementary Material .02 thereto.

In connection with dispositions of ADSs representing Registered Shares, the selling shareholder may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of ADSs representing Registered Shares in the course of hedging in positions they assume. The selling shareholder may also sell ADSs representing Registered Shares short and, if such short sale shall take place after the date that the registration statement of which this prospectus forms a part is declared effective by the Commission, the selling shareholder may deliver ADSs representing Registered Shares to close out short positions and to return borrowed shares in connection with such short sales. The selling shareholder may also loan or pledge ADSs representing Registered Shares to broker-dealers that in turn may sell such shares, to the extent permitted by applicable law. The selling shareholder may also enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the delivery to such broker-dealer or other financial institution of Registered Shares, which shares such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction). Notwithstanding the foregoing, the selling shareholder has been advised that it may not use Registered Shares to cover short sales of our shares (or ADSs representing shares) made prior to the date the amended registration statement of which this prospectus forms a part has been declared effective by the SEC.

The selling shareholder may, from time to time, pledge or grant a security interest in some or all of the warrants or ADSs representing Registered Shares owned by it and, if it defaults in the performance of its secured obligations, the pledgees or secured parties may offer and sell the ADSs representing Registered Shares from time to time pursuant to this prospectus or any amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the Securities Act, amending, if necessary, the list of selling shareholders to include the pledgee, transferee or other successors in interest as a selling shareholder under this prospectus. The selling shareholder also may transfer and donate the ADSs representing Registered Shares in other circumstances, in which case the transferees, donees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.

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The selling shareholder and any broker-dealer or agents participating in the distribution of the ADSs representing Registered Shares may be deemed to be "underwriters" within the meaning of Section 2(a)(11) of the Securities Act in connection with such dispositions. In such event, any commissions paid, or any discounts or concessions allowed to, any such broker-dealer or agent and any profit on the resale of the ADSs representing our Registered Shares purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. If the selling shareholder is an "underwriter" within the meaning of Section 2(a)(11) of the Securities Act will be subject to the applicable prospectus delivery requirements of the Securities Act including Rule 172 thereunder and may be subject to certain statutory liabilities of, including but not limited to, Sections 11, 12 and 17 of the Securities Act and Rule 10b-5 under the Securities Exchange Act of 1934, as amended, or the Exchange Act.

Upon our being notified in writing by the selling shareholder that it is a registered broker-deal or that it has entered into any material arrangement with a broker-dealer for the sale of ADSs representing Registered Shares through a block trade, special offering, exchange distribution or secondary distribution or a purchase by a broker or dealer, a supplement to this prospectus will be filed, if required, pursuant to Rule 424(b) under the Securities Act, disclosing (i) the name of each such selling shareholder and of the participating broker-dealer(s), (ii) the number of ADSs representing Registered Shares involved, (iii) the price at which such ADSs representing Registered Shares were sold, (iv) the commissions paid or discounts or concessions allowed to such broker-dealer(s), where applicable, (v) that such broker-dealer(s) did not conduct any investigation to verify the information set out or incorporated by reference in this prospectus, and (vi) other facts material to the transaction.

The selling shareholder and any other person participating in such distribution will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including, without limitation, to the extent applicable, Regulation M of the Exchange Act, which may limit the timing of purchases and sales of any of ADSs representing Registered Shares by the selling shareholder and any other participating person. To the extent applicable, Regulation M may also restrict the ability of any person engaged in the distribution of the ADSs representing Registered Shares to engage in market-making activities with respect thereto. All of the foregoing may affect the marketability of ADSs representing Registered Shares and the ability of any person or entity to engage in market-making activities with respect thereto.

We will pay all expenses of the registration of ADSs representing our shares pursuant to the registration rights agreement with respect thereto, including, without limitation, SEC filing fees and expenses of compliance with state securities or "blue sky" laws, if any; provided, however, that the selling shareholder will pay all underwriting discounts and selling commissions, if any, incurred by such selling shareholder in connection with the disposition of Registered Shares. We will indemnify the selling shareholder against certain liabilities, including some liabilities under the Securities Act, in accordance with the Registration Rights Agreement, or the selling shareholder will be entitled to contribution. We may be indemnified by the selling shareholder against civil liabilities, including liabilities under the Securities Act, that may arise from any written information furnished to us by the selling shareholder specifically for use in this prospectus, in accordance with the related registration rights agreements, or we may be entitled to contribution.

We are not party to any arrangement with the selling shareholder or any broker-dealer with respect to disposition of ADSs or Registered Shares, other than the Registration Rights Agreement described in the foregoing paragraph. Therefore, we will not have any input if, when and how any selling shareholder elects to dispose of ADSs representing the selling shareholder's Registered Shares or the price or prices at which any such disposition may occur, and there can be no assurance that the selling shareholder will exchange its Registered Shares for ADSs or dispose of any or all of the ADSs representing such shares even if so exchanged pursuant to the deposit agreement governing the ADSs. We will not receive proceeds from any disposition of Registered Shares in the form of ADSs by the selling shareholder.

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SERVICE OF PROCESS AND ENFORCEMENT OF JUDGMENTS

We are organized under the laws of Switzerland and our registered office and domicile is located in Plan-les-Ouates, Geneva, Switzerland. Moreover, a number of our directors and executive officers and a number of directors of each of our subsidiaries are not residents of the United States, and all or a substantial portion of the assets of such persons are located outside the United States. As a result, it may not be possible for investors to effect service of process within the United States upon us or upon such persons or to enforce against them judgments obtained in U.S. courts, including judgments in actions predicated upon the civil liability provisions of the federal securities laws of the United States. We have been advised by our Swiss counsel that there is doubt as to the enforceability in Switzerland of original actions, or in actions for enforcement of judgments of U.S. courts, of civil liabilities to the extent solely predicated upon the federal and state securities laws of the United States. Original actions against persons in Switzerland based solely upon the U.S. federal or state securities laws are governed, among other things, by the principles set forth in the Swiss Federal Act on International Private Law of 1987, as amended, or PILA. This statute provides that the application of provisions of non-Swiss law by the courts in Switzerland shall be precluded if the result was incompatible with Swiss public policy. Also, mandatory provisions of Swiss law may be applicable regardless of any other law that would otherwise apply.

Switzerland and the United States do not have a treaty providing for reciprocal recognition of and enforcement of judgments in civil and commercial matters. The recognition and enforcement of a judgment of the courts of the United States in Switzerland is governed by the principles set forth in the PILA. This statute provides in principle that a judgment rendered by a non-Swiss court may be enforced in Switzerland only if:

•: the non-Swiss court had jurisdiction pursuant to the PILA;
•: the judgment of such non-Swiss court has become final and non-appealable;
•: the judgment does not contravene Swiss public policy;
•: the court procedures and the service of documents leading to the judgment were in accordance with the due process of law; and
•: no proceeding involving the same position and the same subject matter was first brought in Switzerland, or adjudicated in Switzerland, or was earlier adjudicated in a third state and this decision is recognizable in Switzerland.

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EXPENSES

The following table sets forth the expenses (other than underwriting discounts and commissions or agency fees and other items constituting underwriters' or agents' compensation, if any) expected to be incurred by us in connection with a possible offering of securities registered under this registration statement. All amounts are estimated except for the SEC registration fee and FINRA filing fee.

	Amount To Be Paid

SEC registration fee	$	17,859
FINRA filing fee	$	23,000
Transfer agent's fees			*
Printing and engraving expenses			*
Legal fees and expenses			*
Accounting fees and expenses			*
Miscellaneous			*

Total	$		*

*: To be provided by a prospectus supplement or a Report on Form 6-K that is incorporated by reference into this prospectus.

LEGAL MATTERS

Unless otherwise indicated in any prospectus supplement, Cooley LLP, New York, New York, will be representing us in connection with any offering and will pass upon certain matters of U.S. federal and New York law. Unless otherwise indicated in any prospectus supplement, Homburger AG will pass upon the validity of the securities to be offered and other legal matters relating to Swiss law. Additional legal matters may be passed upon for any underwriters, dealers or agents by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements as of December 31, 2020, and for year ended December 31, 2020 incorporated by reference in this prospectus have been so incorporated in reliance on the report of BDO AG, an independent registered public accounting firm, incorporated herein by reference, given on the authority of said firm as experts in auditing and accounting.

The consolidated financial statements as of December 31, 2019, and for each of the two years in the period ended December 31, 2019 incorporated in this prospectus by reference to the Annual Report on Form 20-F for the year ended December 31, 2020 have been so incorporated in reliance on the report of PricewaterhouseCoopers SA, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting. PricewaterhouseCoopers SA is a member of EXPERTsuisse—Swiss Expert Association for Audit, Tax and Fiduciary.

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WHERE YOU CAN FIND MORE INFORMATION

We are subject to the information reporting requirements of the Exchange Act applicable to foreign private issuers. Accordingly, we are required to file reports and other information with the SEC, including annual reports on Form 20-F and periodic reports on Form 6-K. Those reports may be obtained at the website described above. As a foreign private issuer, we are exempt from the rules under the Exchange Act related to the furnishing and content of proxy statements, and our officers, directors and principal shareholders will be exempt from the reporting and short-swing profit recovery provisions contained in Section 16 of such act. In addition, we are not required under the Exchange Act to file periodic reports and financial statements with the SEC as frequently or as promptly as U.S. companies whose securities are registered thereunder.

The SEC maintains a web site that contains reports and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website is www.sec.gov.

This prospectus and any prospectus supplement are part of a registration statement on Form F-3 that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement of which this prospectus forms a part. Statements in this prospectus or any prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement through the SEC's website, as provided above.

We also maintain a website at www.addextherapeutics.com/en/ through which you can access our SEC filings. Information contained in, or that can be accessed through, our website is not a part of, and shall not be incorporated by reference into, this prospectus. We have included our website address in this prospectus solely as an inactive textual reference.

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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to "incorporate by reference" into this prospectus and any accompanying prospectus supplement the information we have filed with the SEC. This means that we can disclose important information by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be a part of this prospectus, and information that we file later with the SEC will also be deemed to be incorporated by reference into this prospectus and to be a part hereof from the date of filing of such documents and will automatically update and supersede previously filed information, including information contained in this document.

We incorporate by reference into this prospectus and any accompanying prospectus supplement the following documents that we have filed with the SEC:

•: Our Annual Report on Form 20-F for the fiscal year ended December 31, 2020, filed with the SEC on March 11, 2021;
•: Our reports on Form 6-K furnished to the SEC on January 12, 2021, January 21, 2021, February 16, 2021, February 17, 2021 and March 11, 2021; and
•: The description of our shares contained in our Registration Statement on Form 8-A, filed with the SEC on January 14, 2020, including any amendments or reports filed for the purposes of updating this description.

We are also incorporating by reference all subsequent annual reports on Form 20-F that we file with the SEC and those of our current reports on Form 6-K that we furnish to the SEC that we specifically identify in such form or in any applicable prospectus supplement as being incorporated by reference into this prospectus or such prospectus supplement after the date hereof and prior to the completion of an offering of securities under this prospectus.

We will furnish without charge to each person, including any beneficial owner, to whom a prospectus is delivered, on written or oral request, a copy of any or all of the documents incorporated by reference in this prospectus, including exhibits to these documents. You should direct any requests for documents, either in writing to Addex Therapeutics Ltd, Attn: Head of Finance, Chemin des Mines 9, CH-1202 Geneva, Switzerland, or by telephone at +41 22 884 1555.

You also may access these filings on our website at www.addextherapeutics.com/en/ through which you can access our SEC filings. Information contained in, or that can be accessed through, our website is not a part of, and shall not be incorporated by reference into, this prospectus. We have included our website address in this prospectus solely as an inactive textual reference.

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus or any prospectus supplement will be deemed modified, superseded or replaced for purposes of this prospectus or any prospectus supplement to the extent that a statement contained in any other subsequently filed document that also is or is deemed to be incorporated by reference in this prospectus or any prospectus supplement modifies, supersedes or replaces such statement. Any statement that is modified or superseded will not constitute a part of this prospectus or prospectus supplement, except as modified or superseded.

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Addex Therapeutics Ltd

$150,000,000 of Shares Offered by the Company
and
7,704,600 Shares Offered by the Selling Shareholder
(Each Including Shares in the Form of American Depositary Shares)

PROSPECTUS

, 2021

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 8. Indemnification of Directors and Officers.

Under Swiss law, a corporation may indemnify its directors or officers against losses and expenses (except for such losses and expenses arising from willful misconduct or negligence, although legal scholars advocate that at least gross negligence be required), including attorney's fees, judgments, fines and settlement amounts actually and reasonably incurred in a civil or criminal action, suit or proceeding by reason of having been the representative of, or serving at the request of, the corporation.

We have entered into indemnification agreements with each of our directors and executive officers. These agreements require us to indemnify our directors and executive officers to the fullest extent permitted by law. However, under Swiss corporate law, the indemnification of our directors and executive officers is not effective if such director or executive officer intentionally or grossly negligently violated his or her corporate duties towards the corporation, each of its shareholders or creditors.

In addition, under general principles of Swiss employment law, an employer may be required to indemnify an employee against losses and expenses incurred by such employee in the proper execution of their duties under the employment agreement with the company.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant, the registrant has been advised that, in the opinion of the U.S. Securities and Exchange Commission, such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.

Item 9. Exhibits.

The following exhibits are filed herewith:

		Description

1.1	*	Form of Underwriting Agreement

4.1		Articles of Association of Addex Therapeutics Ltd (incorporated by reference to Exhibit 3.1 of Registration Statement on Form F-1 No. 333-251322)

4.2		Organizational Rules of Addex Therapeutics Ltd (incorporated by reference to Exhibit 3.2 of Registration Statement on Form F-1 No. 333-235554)

4.3		Form of Deposit Agreement (incorporated by reference to Exhibit (a) of the Registration Statement on Form F-6 (No. 333-235561), filed on December 18, 2019)

4.4		Form of American Depositary Receipt (included in Exhibit 4.3)

4.5		Form of Warrant issued by Addex Therapeutics Ltd to certain investors on March 28, 2018 (incorporated by reference to Exhibit 4.3 of Registration Statement on Form F-1 No. 333-235554)

5.1		Opinion of Homburger AG

23.1		Consent of BDO SA

23.2		Consent of PricewaterhouseCoopers SA

23.3		Consent of Homburger AG (included in Exhibit 5.1)

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Exhibit No.			Description

	24.1		Power of Attorney of certain directors and officers of the registrant (included on signature page of this registration statement)

*: To be filed, if necessary, as an exhibit to a post-effective amendment to this registration statement or as an exhibit to a report filed under the Securities Exchange Act of 1934, as amended, and incorporated herein by reference.

Item 10. Undertakings.

(a)

The undersigned registrant hereby undertakes:

(1)

To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i): To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;
(ii): To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement.
(iii): To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement.

Provided, however, That:

(A) Paragraphs (a)(1)(i) and (a)(1)(ii) of this section do not apply if the registration statement is on Form S-8 (§ 239.16b of this chapter), and the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)) that are incorporated by reference in the registration statement; and

(B) Paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the registration statement is on Form S-3 (§ 239.13 of this chapter) or Form F-3 (§ 239.33 of this chapter) and the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) (§ 230.424(b) of this chapter) that is part of the registration statement.

(C) Provided further, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the registration statement is for an offering of asset-backed securities on Form S-1 (§ 239.11 of this chapter) or Form S-3 (§ 239.13 of this chapter), and the information required to be included in a post-effective amendment is provided pursuant to Item 1100(c) of Regulation AB (§ 229.1100(c)).

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(2)

That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3)

To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4)

To file a post-effective amendment to the registration statement to include any financial statements required by Item 8.A. of Form 20-F at the start of any delayed offering or throughout a continuous offering. Financial statements and information otherwise required by Section 10(a)(3) of the Securities Act of 1933 need not be furnished, provided that the registrant includes in the prospectus, by means of a post-effective amendment, financial statements required pursuant to this paragraph (a)(4) and other information necessary to ensure that all other information in the prospectus is at least as current as the date of those financial statements. Notwithstanding the foregoing, with respect to registration statements on Form F-3, a post-effective amendment need not be filed to include financial statements and information required by Section 10(a)(3) of the Securities Act of 1933 or Rule 3-19 of Regulation S-X if such financial statements and information are contained in periodic reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the Form F-3.

(5)

That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A): Each prospectus filed by a registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and
(B): Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5) or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii) or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which the prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date;

(6)

That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the

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following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i): Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;
(ii): Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;
(iii): The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and
(iv): Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(b): The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(c): Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933, and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form F-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Geneva, Switzerland, on this 7th day of April, 2021.


		Addex Therapeutics Ltd
		By:		/s/ TIM DYER Tim Dyer Chief Executive Officer

POWER OF ATTORNEY

We, the undersigned directors, officers and/or authorized representative in the United States of Addex Therapeutics Ltd, hereby severally constitute and appoint Tim Dyer and Lénaic Teyssédou, and each of them singly, our true and lawful attorneys, with full power to any of them, and to each of them singly, to sign for us and in our names in the capacities indicated below the registration statement on Form F-3 filed herewith, and any and all pre-effective and post-effective amendments to said registration statement, and any registration statement filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended, in connection with the registration under the Securities Act of 1933, as amended, of securities of Addex Therapeutics Ltd, and to file or cause to be filed the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as each of them might or could do in person, and hereby ratifying and confirming all that said attorneys, and each of them, or their substitute or substitutes, shall do or cause to be done by virtue of this Power of Attorney.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date


/s/ TIM DYER Tim Dyer	Chief Executive Officer and Director (Principal Executive Officer)	April 7, 2021
/s/ LÉNAIC TEYSSÉDOU Lénaic Teyssédou	Head of Finance (Principal Financial Officer and Principal Accounting Officer)	April 7, 2021
/s/ VINCENT LAWTON Vincent Lawton	Chairman of the Board of Directors	April 7, 2021
/s/ RAY HILL Ray Hill	Director	April 7, 2021

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Signature	Title	Date


/s/ ISAAC MANKE Isaac Manke	Director	April 7, 2021
/s/ ROGER MILLS Roger Mills	Director	April 7, 2021
/s/ JAKE NUNN Jake Nunn	Director	April 7, 2021

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Authorized Representative in the United States


Addex Pharmaceuticals Inc.
By:	/s/ TIM DYER Name: Tim Dyer Title: Chief Executive Officer	Authorized Representative in the United States	April 7, 2021