Mabion launches the first phase of cooperation with Oddifact SAS on the development of MabionCD20 for orphan diseases

Phone +48 42 207 78 90 Email address: [email protected] www.mabion.eu 1 Poland, Konstantynów Łódzki, 16th June, 2026 Press release Mabion launches the first phase of cooperation with Oddifact SAS on the development of MabionCD20 for orphan diseases On June 16th, 2026, Mabion S.A. and Oddifact SAS signed an agreement setting out the terms of the first phase of cooperation (in accordance with the letter of intent entered into by the parties) to investigate and evaluate the potential use of MabionCD20 in a new clinical indication in the field of orphan diseases The first phase of the collaboration involves preparatory work to ready the MabionCD20 project for consultation with the US Food and Drug Administration (FDA) regarding a therapeutic indication selected by the parties. In the Company’s assessment, the potential annual market value of treatment with the CD20 monoclonal antibody in this indication in the United States may be estimated at approximately USD 100 million The collaboration with Oddifact SAS marks another milestone in the execution of Mabion’s 2025 –2030 Strategy. Alongside the continued growth of its CDMO operations and services for external clients, the Company is leveraging its extensive expertise in monoc lonal antibody development to advance high - value projects built on its proprietary know-how and intellectual property portfolio Mabion will provide access to data and documentation regarding the development of MabionCD20 to date, as well as scientific and technical support, whilst Oddifact SAS will support the further development of the project using advanced analytical tools and artificial intelligence (AI), including the design of a clinical trial programme Following the conclusion of the agreement, the Management Board of Mabion S.A. decided to reverse the impairment loss on inventories allocated to the MabionCD20 project in the amount of approximately PLN 4.79 million “The conclusion of the agreement with Oddifact SAS launches the first phase of work aimed at verifying the potential of MabionCD20 in a new therapeutic area. The collaboration combines our experience in the development of monoclonal antibodies with an approach based on advanced analytics and AI tools, which may help in the efficient preparation of the project for regulatory dialogue with the FDA” – said Gregor Kawaletz, Chief Executive Officer of Mabion S.A. “Today’s agreement demonstrates Mabion’s continued commitment to delivering on its 2025 –2030 Strategy. While expanding our CDMO operations remains a key priority, we also see substantial opportunities in unlocking the value of the scientific expertise, assets and intellectual property we have built over the years. Through our collaboration with Oddifact, MabionCD20 has the potential to become a compelling example of how deep biologics expertise can be combined with advanced data analytics and artificial intelligence to accelerate innovative drug development” – adds Gregor Kawaletz. “MabionCD20 remains a project with significant scientific and commercial potential. The successful completion of the first phase and consultations with the FDA will form the basis for discussions on the next stage of collaboration, involving the further development of the project in a selected indication” – comments Detlef Behrens, Chief Business Affairs Officer of Mabion S.A. Under the terms of the agreement, Mabion S.A. and Oddifact SAS will commence work aimed at preparing the MabionCD20 project for consultation with the FDA. The subject of the consultation will be the development of the project in a therapeutic indication selected by the parties from the field of orphan diseases. Phone +48 42 207 78 90 Email address: [email protected] www.mabion.eu 2 In accordance with the arrangements, the parties will cooperate on the preparation of regulatory documentation, the design of a clinical trial programme, and the development of a registration, manufacturing and commercialisation strategy for MabionCD20 in the selected indication. If the work under the first phase and the consultations with the FDA are successful, the parties will proceed to agree on the terms of the second phase of cooperation. In parallel, the Management Board of Mabion S.A. has conducted a re-analysis of the economic usefulness of the stock of materials allocated to the MabionCD20 project and previously subject to a write -down of approximately PLN 4.8 million. Considering the current circumstances regarding the use of these materials in the reactivated project, the Management Board considered it appropriate to restore their carrying amount and decided to reverse the impairment loss in the amount of approximately PLN 4.79 million. The reactivation of the MabionCD20 project supports Mabion’s strategic objective of diversifying its business by advancing selected proprietary programmes that complement its core CDMO operations and create additional long -term growth opportunities for the Company. About Oddifact SAS ODDIFACT is a TechDev platform that transforms off-label uses of existing medicines into approved treatments for patients suffering from rare diseases. Its proprietary AI -based platform, S.A.V.E., identifies promising off -label opportunities emerging in real-world medical practice and transforms them into complete ‘orphan drug programmes’, which are then licensed to pharmaceutical companies for regulatory approval and commercialisation. These programmes include orphan drug designations, clinical evidence, C MC, supply agreements, regulatory strategy and commercialisation plans. In line with its mission to unlock the untapped potential of medical research and accelerate patient access to treatment, ODDIFACT has secured 13 FDA orphan drug designations in less t han 24 months, becoming one of the most prolific generators of orphan drug designations in the world and offering a faster, cheaper and risk -free alternative to traditional drug development. Contact for media and individual investors Michał Wierzchowski +48 531 613 067 +48 22 440 14 40 [email protected] Mardoniusz Maćkowiak +48 605 959 539 +48 22 440 14 40 [email protected] Contact for institutional investors and analysts Piotr Owdziej +48 697 612 913 +48 22 440 14 40 [email protected] Information about Mabion Mabion S.A. (WSE:MAB) is a publicly traded Polish biopharmaceutical company, founded in 2007, which underwent a transformatio n in 2023–2024 into a biologics -focused CDMO (Contract Development and Manufacturing Organization) offering an integrated service portfolio. Mabion specializes in small to mid -sized projects at various stages of development – from early-stage development of stable cell lines to commercial manufacturing. Mabion’s core competencies include monoclonal antibody development technologies, recombinant protein production (using mammalian and insect cell expression systems), advanced analytics, and manufacturing of Drug Substance. The company operates in compliance with globally recognized quality standards, including GMP, GCP, and ISO. Mabion employs over 200 highly qualified professionals, including scientists, engineers and experts in quality, manufacturing and analytical development for biologics. Headquartered in the center of Europe, Mabion operates in Poland – an EU member state – providing access to highly regulated markets. The company's mission is to be a trusted global partner for the development and manufacturing of biologic medicines. Mabion is a public company listed on the Warsaw Stock Exchange. More information: www.mabion.eu

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