Santhera Pharmaceuticals Holding AG

Santhera extends Highbridge convertible bond to 30th September 2025

Ad hoc announcement pursuant to Art. 53 LRA

Pratteln, Switzerland, 15 August, 2025 – Santhera Pharmaceuticals (SIX: SANN) announces that by mutual agreement the Company and Highbridge Capital Management, LLC (Highbridge) have decided to extend the maturity date of the existing CHF 7 million private convertible bond, that has a strike price of CHF 10.00, to 30^th September 2025.

About Santhera
Santhera Pharmaceuticals (SIX: SANN) is a Swiss specialty pharmaceutical company focused on the development and commercialization of innovative medicines for rare neuromuscular diseases with high unmet medical need. The Company has an exclusive license from ReveraGen for all indications worldwide to AGAMREE® (vamorolone), a dissociative steroid with novel mode of action, which was investigated in a pivotal study in patients with Duchenne muscular dystrophy (DMD) as an alternative to standard corticosteroids. AGAMREE for the treatment of DMD is approved in the U.S. by the Food and Drug Administration (FDA), in the EU by the European Medicines Agency (EMA), in the UK by the Medicines and Healthcare products Regulatory Agency (MHRA), in China by the National Medical Products Administration (NMPA) and Hong Kong by the Department of Health (DoH). Santhera has out-licensed rights to AGAMREE for North America to Catalyst Pharmaceuticals and for China and certain countries in Southeast Asia to Sperogenix Therapeutics. For further information, please visit www.santhera.com.

AGAMREE® is a trademark of Santhera Pharmaceuticals.

For further information please contact:

Santhera
Catherine Isted, Chief Financial Officer:

IR@santhera.com

ICR Healthcare

Santhera@icrhealthcare.com

Disclaimer / Forward-looking statements
This communication does not constitute an offer or invitation to subscribe for or purchase any securities of Santhera Pharmaceuticals Holding AG. This publication may contain certain forward-looking statements concerning the Company and its business. Such statements involve certain risks, uncertainties and other factors which could cause the actual results, financial condition, performance or achievements of the Company to be materially different from those expressed or implied by such statements. Readers should therefore not place undue reliance on these statements, particularly not in connection with any contract or investment decision. The Company disclaims any obligation to update these forward-looking statements.

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Attachment

• 250815 Highbridge Convertible Bond_ENGLISH_FINAL