Lenaic Nathanael Teyssedou, Principal Accounting Officer of Addex Therapeutics Ltd. (NASDAQ:ADXN), filed a Form 4 on November 13, 2026, disclosing the acquisition of stock options on November 11, 2026.

Key Highlights

  • Reporting person: Lenaic Nathanael Teyssedou, identified as Principal Accounting Officer of Addex Therapeutics Ltd.
  • Transaction date: November 11, 2026, with transaction code "A" (acquired).
  • Options granted: 3,771,415 stock options (Right to Buy), each granting the right to purchase one ADXN share listed on SIX Swiss Exchange.
  • Exercise price: $0.026 per share, converted from CHF to USD at an exchange rate of $1.1995 per CHF 1.00 as of November 11, 2026.
  • Vesting schedule: Options vest in equal monthly installments over a 4-year period beginning at the exercisable date of November 11, 2026.
  • Expiration date: November 10, 2036.
  • Total derivative securities beneficially owned following the transaction: 4,374,323, held directly.

Addex Therapeutics Principal Accounting Officer Acquires Options Vesting Over Four Years

According to the Form 4 filed with the U.S. Securities and Exchange Commission, Lenaic Nathanael Teyssedou, serving as Principal Accounting Officer at Addex Therapeutics Ltd. (NASDAQ:ADXN), acquired 3,771,415 stock options on November 11, 2026. The price of the derivative security at acquisition was reported as $0, and the exercise price was listed as $0.026 per share in U.S. dollars.

The filing disclosed that the exercise price reflects a conversion from Swiss francs to U.S. dollars at an exchange rate of $1.1995 per CHF 1.00 as of November 11, 2026. Each stock option grants the right to purchase one ADXN share listed on the SIX Swiss Exchange. According to the filing, the options vest in equal monthly installments over a four-year period beginning at the exercisable date of November 11, 2026, and expire on November 10, 2036.

Following this transaction, the filing reported that Teyssedou beneficially owns 4,374,323 derivative securities in total, held directly. No non-derivative securities transactions were reported in Table I of the filing. The reporting person's address is listed as Chemin des Mines 9, Geneva, Switzerland. The form was filed by one reporting person and was not indicated as an amendment to a prior filing.

What Was Disclosed

Addex Therapeutics Ltd.'s Principal Accounting Officer disclosed the acquisition of 3,771,415 stock options on November 11, 2026, exercisable at $0.026 per share and expiring November 10, 2036, with total beneficial ownership of 4,374,323 derivative securities following the transaction.