PRESS RELEASE

Heidelberg Pharma to Present New Data on its Proprietary ATAC^(R) Technology Platform at the AACR Annual Meeting 2022

Ladenburg, Germany, 7 April 2022 - Heidelberg Pharma AG (FSE: HPHA) announced today that it will present preclinical data on its proprietary Amanitin-based ATAC^(R) technology at the American Association for Cancer Research (AACR) 2022 Annual Meeting. The meeting will take place in New Orleans, Louisiana, USA, from 8^th - 13^th April 2022.

Details of the poster presentation:
Amatoxin-based antibody-drug conjugates induce immunogenic cell death and improve the anti-tumor efficacy of immune checkpoint inhibitors in humanized mouse models

Abstract number: 1754, Section 21
Session: Experimental and Molecular Therapeutics, Antibody-Drug Conjugates
Date and time: 11^th April 2022, 01:30 PM - 05:00 PM CDT (08:30 PM - 12:00 AM CEST)
Presenter: Dr. Christian Orlik
Link to the abstract: https://www.abstractsonline.com/pp8/#!/10517/presentation/12238

The poster shows preclinical data on the synergies of ATACs^(R) together with immune checkpoint inhibitors. In breast cancer models, treatment with ATACs^(R) induced immunogenic cell death, leading to activation of the immune system. Combining this immunostimulatory property of ATACs^(R) with immune checkpoint inhibitors led to a greater anti-tumor response in a preclinical lymphoma model and may represent a promising approach for further oncological therapies.

Details of the poster presentation:
Treatment with ATAC^(R) based ADCs induces tolerability in preclinical animal models without triggering tolerance

Abstract number: 1761, Section 21
Session: Experimental and Molecular Therapeutics, Antibody-Drug Conjugates
Date and time: 11^th April 2022, 01:30 PM - 05:00 PM CDT (08:30 PM - 12:00 AM CEST)
Presenter: Dr. Kristin Decker
Link for the abstract: https://www.abstractsonline.com/pp8/#!/10517/presentation/12237

The poster shows preclinical data indicating that repeat dosing with ATACs^(R) induces tolerability in preclinical models without a loss in efficacy. Consequently, if this increased tolerability after pre-treatment with ATACs^(R) also hold true in the clinic, it might provide an indication of an optimized treatment regimen and support the clinical success of ATACs^(R).

Online poster presentations will be available on the AACR website (https://www.aacr.org/meeting/aacr-annual-meeting-2022/) beginning Friday, 8^th April 2022, 01:00 PM CDT (08:00 PM CEST).

On the company website, the posters will be available under "Press & Investors > Calendar and Presentations > Scientific Posters" from 13^th April 2022.

About Heidelberg Pharma's proprietary ATAC^(R) technology

Antibody Drug Conjugates (ADCs) combine the high affinity and specificity of antibodies with the potency of cytotoxic small molecules for the treatment of cancer. Heidelberg Pharma works with ADCs based on its proprietary ATAC^(R) technology platform using Amanitin as active ingredient. Amanitin belongs to the amatoxin molecules. Amatoxins are small bicyclic peptides naturally occurring in the death cap mushroom. They inhibit mRNA transcription by binding to RNA polymerase II, a mechanism that is crucial for the survival of eukaryotic cells. In preclinical testing, ATACs^(R) have been shown to be highly efficacious, overcoming frequently encountered resistance mechanisms and combating even quiescent tumor cells.

About Heidelberg Pharma

Heidelberg Pharma is an oncology specialist and the first company to develop the toxin Amanitin into cancer therapies using its proprietary ATAC^(R) technology and to advance the biological mode of action of the toxin as a novel therapeutic principle. The proprietary technology platform is being applied to develop the Company's own therapeutic ATACs^(R) as well as in third-party collaborations. The lead candidate HDP-101 is a BCMA ATAC in clinical development for multiple myeloma. HDP-102, a CD37 ATAC for Non-Hodgkin lymphoma and HDP-103, a PSMA ATAC for metastatic castration-resistant prostate cancer, are in preclinical testing.

Heidelberg Pharma AG is based in Ladenburg, Germany, and is listed on the Frankfurt Stock Exchange: ISIN DE000A11QVV0 / WKN A11QVV / Symbol HPHA. More information is available at http://www.heidelberg-pharma.com/.

ATAC^(R) is a registered EU trademark of Heidelberg Pharma Research GmbH.

This communication contains certain forward-looking statements relating to the Company's business, which can be identified by the use of forward-looking terminology such as "estimates", "believes", "expects", "may", "will" "should" "future", "potential" or similar expressions or by a general discussion of the Company's strategy, plans or intentions. Such forward-looking statements involve known and unknown risks, uncertainties and other factors, which may cause our actual results of operations, financial condition, performance, or achievements, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Given these uncertainties, prospective investors and partners are cautioned not to place undue reliance on such forward-looking statements. We disclaim any obligation to update any such forward-looking statements to reflect future events or developments.