Heidelberg Pharma Reports on the Results of the Ordinary Annual General Meeting 2026

PRESS RELEASE All agenda items approved by a large majority 2026 Annual General Meeting elects Jack Yefei Ling as new member of the Supervisory Board Ladenburg, Germany, 23 June 2026 – Heidelberg Pharma AG (FSE: HPHA), a clinical-stage biotech company developing innovative Antibody Drug Conjugates (ADCs), today announced that the company's shareholders approved the management proposals with a large majority (between 98.67% and 98.72%) at today's ordinary virtual Annual General Meeting. All members of the Management Board and Supervisory Board formally approved for the 2024/2025 financial year Auditors for the 2025/2026 financial year appointed Remuneration report for the Management Board approved Election of Mr. Jack Yefei Ling as new member of the Supervisory Board Resolution on the amendment to the Articles of Association regarding the reduction in the size of the Supervisory Board from seven to five members Attendance (incl. postal votes cast) at the 2026 Annual General Meeting corresponded to 80.55% of the current capital stock. For more information on the Annual General Meeting, including the voting results, please visit: https://heidelberg-pharma.com/en/agm. About Heidelberg Pharma Heidelberg Pharma is the first company to develop cancer therapies using Amanitin, a compound derived from the green death cap mushroom. The biological mechanism of action of the toxin represents a new therapeutic modality and is used as a compound in the Amanitin-based ADC technology, the so-called ATAC technology. The lead candidate HDP-101 (INN: pamlectabart tismanitin) is a BCMA ATAC in clinical development for multiple myeloma. The candidate has been granted Orphan Drug Designation and Fast Track Designation from the FDA. A second ATAC candidate, HDP-102 is in clinical development stage in Non-Hodgkin Lymphoma. HDP-103 against metastatic castration-resistant prostate cancer and HDP-104 targeting gastrointestinal tumors such as colorectal cancer have completed preclinical development. These programs are available for partnering. The company is based in Ladenburg, Germany, and is listed on the Frankfurt Stock Exchange: ISIN DE000A11QVV0 / WKN A11QVV / Symbol HPHA. More information is available at www.heidelberg-pharma.com ATAC® is a registered trademark of Heidelberg Pharma Research GmbH.

Contact Heidelberg Pharma AG Sylvia Wimmer Senior Director Corporate Communications Tel.: +49 6203 1009 1004 E-Mail: investors@hdpharma.com Gregor-Mendel-Str. 22, 68526 Ladenburg

IR/PR-Support MC Services AG Katja Arnold (CIRO) Managing Director & Partner Tel.: +49 89 210 228-40 E-Mail: katja.arnold@mc-services.eu

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