# EDGAR Filing Document

**Accession Number:** 0001830908
**File Stem:** 0001104659-25-061660
**Filing Date:** 2025-6
**Character Count:** 7299
**Document Hash:** bc18a176962f61b247a4d2264ae22b5c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-061660.hdr.sgml**: 20250623

**ACCESSION NUMBER**: 0001104659-25-061660

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D/A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250623

**DATE AS OF CHANGE**: 20250623

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Addex Therapeutics Ltd.
- **CENTRAL INDEX KEY:** 0001574232
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** V8
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-91805
- **FILM NUMBER:** 251064886

**BUSINESS ADDRESS:**
- **STREET 1:** CHEMIN DES MINES 9
- **CITY:** GENEVA
- **STATE:** V8
- **ZIP:** CH-1202
- **BUSINESS PHONE:** 01141228841555

**MAIL ADDRESS:**
- **STREET 1:** CHEMIN DES MINES 9
- **CITY:** GENEVA
- **STATE:** V8
- **ZIP:** CH-1202
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Dyer Timothy Mark
- **CENTRAL INDEX KEY:** 0001830908

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A

**MAIL ADDRESS:**
- **STREET 1:** CHEMIN DES MINES 9
- **STREET 2:** CH-1202
- **CITY:** GENEVA
- **STATE:** V8
- **ZIP:** CH-1202

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

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**(Amendment No. 8)**

**Addex Therapeutics Ltd.**

*(Name of Issuer)*

**American Depositary Shares, each representing 120 ordinary shares Ordinary shares**

*(Title of Class of Securities)*

**00654J206**

*(CUSIP Number)*

**Timothy Mark Dyer**<br>c/o Addex Therapeutics Ltd<br>Chemin des Mines 9<br>Geneva V8 CH-1202<br>41 22 884 1555

*(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)*

**06/20/2025**

*(Date of Event Which Requires Filing of this Statement)*

| **CUSIP No.** | **00654J206** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Timothy Mark Dyer** | Name of reporting person<br>**Timothy Mark Dyer** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**PF** | Source of funds (See Instructions)<br>**PF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**V8** | Citizenship or place of organization<br>**V8** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**18208437.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**18208437.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**0.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**18208437.00** | Aggregate amount beneficially owned by each reporting person<br>**18208437.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**12.94%** | Percent of class represented by amount in Row (11)<br>**12.94%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Comment for Reporting Person:** (1) Consists of 16,848,979 ordinary shares and 1,359,458 shares issuable upon exercise of options exercisable within 60 days of June 20, 2025.

(2) Represents the percentage ownership based on 139,391,883 ordinary shares of Addex Therapeutics Ltd outstanding asof June 18, 2025, as reported in the latest quarterly report on form 6K (file No.001-39179)  filed on June 20, 2025.

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
American Depositary Shares, each representing 120 ordinary shares Ordinary shares

**(b) Name of Issuer:**
Addex Therapeutics Ltd.

**(c) Address of Issuer's Principal Executive Offices:**
Chemin des Mines 9, Geneva, V8, CH-1202

This Schedule 13D relates to the ordinary shares, nominal value CHF 0.01 per share (the "Shares"), of Addex Therapeutics Ltd (the "Issuer"). The Issuer's principal executive office is located at Chemin des Mines 9, CH- 1202 Geneva, Switzerland.

**Item 4. Purpose of Transaction**

The Reporting Person acquired the securities of the Issuer at founding, through the exercise of options, acquisitions through participation in private placements and in consideration for his services as Chief Executive Officer of the Issuer. The reporting person also received shares issuable upon exercise of options. The terms of the Reporting Person's employment arrangements for 2024 were set forth in the Issuer's Annual Report on Form 20-F for such period filed by the Issuer with the Securities and Exchange Commission on May 15, 2025. Except in respect of such employment arrangements as set forth therein, the Reporting Person does not have any present plans which relate to or would result in:

However, the Reporting Person reserves the right to change its plans at any time, as it deems appropriate, in light of its ongoing evaluation of (i) its business and liquidity objectives; (ii) the Issuer's financial condition, business, operations, competitive position, prospects and/or Share price; (iii) industry, economic and/or securities markets conditions; (iv) alternative investment opportunities; and (v) other relevant factors.

**Item 5. Interest in Securities of the Issuer**

**(a)**
As of the date hereof, Reporting Person beneficially owns 18,208,437 Shares, which represents approximately 12.94% of the Issuer's Shares, consisting of (i) 16,848,979 Shares (ii) 1,359,458 Shares issuable upon exercise of options exercisable within 60 days of June 20, 2025.

**(b)**
Reporting Person may be deemed to hold sole voting and dispositive power over his 18,208,437 Shares of the Issuer.

**(c)**
Other than the acquisition of the shares as reported herein, and as described under Item 4, Reporting Person has not effected any transactions in the shares of the Issuer during the past 60 days or since the most recent filing of Schedule 13D, whichever is less.

**Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.**

The information furnished in Item 3 is incorporated into this Item 6 by reference.

### SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Timothy Mark Dyer

**Signature:** /s/ Timothy Mark Dyer

**Name/Title:** Timothy Mark Dyer

**Date:** 06/23/2025