CSPC PHARMA - VOLUNTARY ANNOUNCEMENT - ENTERING INTO COLLABORATION, OPTION AND LICENSE AGREEMENT WITH ASTRAZENECA FOR THE DEVELOPMENT OF siRNA DRUGS

CSPC PHARMACEUTICAL GROUP LIMITED

石 藥 集 團 有 限 公 司 (Incorporated in Hong Kong with limited liability) (Stock Code: 1093)

VOLUNTARY ANNOUNCEMENT

ENTERING INTO COLLABORATION, OPTION AND LICENSE AGREEMENT WITH ASTRAZENECA FOR THE DEVELOPMENT OF siRNA DRUGS

The Board of Directors (the 'Board') of CSPC Pharmaceutical Group Limited (the 'Company', together with its subsidiaries, the 'Group') is pleased to announce that the Group has entered into a collaboration, option and license agreement (the 'Agreement') with AstraZeneca, a global biopharmaceutical leader, to establish a strategic research collaboration and utilise the Group's proprietary siRNA drug discovery platform and extrahepatic targeted delivery platform (the 'Platforms') to develop novel small nucleic acid drug candidates.

The Platforms utilise the Group's proprietary AI molecular design model and fully automated high-

throughput screening system to efficiently screen nucleic acid drug molecules with high activity and enhanced extrahepatic targeting potential.

Under the terms of the Agreement, the Group and AstraZeneca will jointly discover and develop pre- clinical candidates ('PCC') for two targets, with the potential to treat renal diseases across multiple indications. For each PCC program, AstraZeneca will have the option to obtain the exclusive rights for the development, manufacturing and commercialisation globally or outside of China (as applicable). The Group will retain the rights to develop, manufacture and commercialise one of the PCCs in China.

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In addition, pursuant to the Agreement, the Group will receive an upfront payment of US$30 million and is also eligible to receive up to US$540 million in potential development milestone payments and up to US$1.2 billion in potential sales milestone payments, plus potential single digit royalties based on

the annual net sales of the products. By order of the Board

CSPC Pharmaceutical Group Limited CAI Dong Chen Chairman

Hong Kong, 2 July 2026