TOKYO, May 16, 2023 - Sony Corporation (President and CEO: Kimio Maki, "Sony") and Astellas Pharma Inc. (TSE: 4503, President and CEO: Naoki Okamura, "Astellas") today announced that they have entered into a collaborative research agreement to discover a novel Antibody-Drug Conjugate (ADC)*1 platform in oncology based on Sony's unique polymeric material, "KIRAVIA™*2 Backbone*3." ADC is expected to selectively deliver anti-cancer drugs to target cells, thereby increasing efficacy and reducing side effects caused by anti-cancer drugs attacking normal cells. The technology to create linkers which conjugates antibodies and drugs, is considered to be a key to development of a better-performing ADC. This collaborative research leverages the flexibility in design and resulting properties such as high capacity and solubility of KIRAVIA Backbone as a linker of ADC, to effectively deliver anti-cancer drugs to targeted cells in a stable manner, aiming to further enhance therapeutic efficacy by achieving high Drug-to-Antibody Ratio (DAR) etc.

The two companies jointly began exploratory research of new linker technology aimed at creating a new ADC platform in July 2022, and the expected profile was obtained in feasibility studies using human cancer cells. Under this agreement, Sony and Astellas will jointly develop and optimize a new ADC platform using the KIRAVIA Backbone as a linker. In addition, Astellas will conduct non-clinical trials of development candidates. Furthermore, in order to build a drug discovery platform not limited to ADC, the two companies have agreed to continue discussions on expanding research partnerships to create new value by combining Sony's cutting-edge technology with Astellas' renowned pharmaceutical capabilities.

"Sony's life science business has accumulated substantial knowledge in the field of cell analysis," said Katsunori Ogawa, Head of Life Science & Technology Business Unit at Sony Corporation. "Through this collaboration, Sony is striving to contribute to the medical and drug discovery fields and provide further social value by leveraging Sony's technological capabilities in the development of anti-cancer drugs therapy, which are expected to grow."

"We are pleased to enter into a joint research agreement with Sony," said Yoshitsugu Shitaka, Ph.D., Chief Scientific Officer (CScO), Astellas Pharma Inc. "Astellas is working to create innovative drugs from a multifaceted perspective called the Focus Area approach*4, which identifies combinations of biology, therapeutic modality or technology and diseases with high unmet medical needs. The partnership will further strengthen our ability to utilize suitable modalities. It is our expectation that the collaboration will lead to the continuous creation of innovative drugs for patients around the world."

• *1:ADC is a modality (Types of therapeutic methods such as low-molecular-weight drugs, antibody drugs, nucleic acid drugs, cell therapy, and gene therapy) that combines an antibody and a small molecule such as an anti-cancer drug via a linker. It is expected to selectively deliver anti-cancer drugs to target cells, thereby reducing side effects caused by anti-cancer drugs attacking normal cells.
• *2:KIRAVIA™ and KIRAVIA Dyes™ are registered trademarks or trademarks of Sony Group Inc. or its affiliates.
• *3:KIRAVIA Backbone is created using the organic polymer technology cultivated in KIRAVIA Dyes™, which Sony independently developed and licensed to reagent manufacturers. It features a high degree of freedom in design, as the three-dimensional structure is programmed and polymerized using an automatic synthesizer. While increasing the number of drugs to be added (achieving high-DAR), it is highly stable, such as loading multiple types of drugs, improving water solubility (prevention of aggregation), and cleaving by reacting with intracellular enzymes. Synthesis of linkers with functional properties and selective drug release is expected.

<Concept image of ADC with KIRAVIA Backbone>

• *4:Astellas has established a Focus Area Approach for its research and development strategy. Specifically, our Focus Area Strategy is defined as combinations of three components: (1) biology with high disease relevance, (2) versatile modalities/technologies, and (3) diseases with high unmet medical needs that are expected to be tackled by the first two components. We view this strategy as a way to build a sustainable, expandable drug discovery approach to develop new platforms, leverage expertise and create innovative products.