SIRNAOMICS-B - VOLUNTARY ANNOUNCEMENT - COMPLETION OF FIRST PATIENT DOSING IN THE PHASE II CLINICAL TRIAL OF STP705 FOR MEDICAL AESTHETIC

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Sirnaomics Ltd.

(Incorporated in the Cayman Islands with limited liability) (Stock Code: 2257)

VOLUNTARY ANNOUNCEMENT

COMPLETION OF FIRST PATIENT DOSING IN THE PHASE II CLINICAL TRIAL OF STP705 FOR MEDICAL AESTHETIC

The board (the 'Board') of directors (the 'Directors') of Sirnaomics Ltd. (the 'Company', together with its subsidiaries, the 'Group' or 'Sirnaomics') hereby

informs the shareholders and potential investors of the Company that the Phase II clinical trial evaluating STP705 for aesthetic applications has successfully completed first-dose administration to the inaugural study participant. This achievement represents a material

clinical milestone for the Group's global RNA therapeutics aesthetic pipeline.

The Phase II multi-center trial's primary endpoint is the systematic evaluation of STP705's clinical efficacy for targeted subcutaneous adipose reduction via local administration, paired with rigorous secondary assessments covering safety, tolerability, and local treatment

reaction profiles.

Powered by the Group's proprietary PNP oligonucleotide delivery platform, STP705 enables site-specific gene modulation to drive controlled adipocyte depletion, delivering a

minimally invasive therapeutic alternative to conventional fat-reduction interventions. Clinical readouts generated from this Phase II program will generate pivotal efficacy data to underpin the global development trajectory of the Group's aesthetic asset, further solidifying Sirnaomics' pioneering market positioning in extrahepatic siRNA delivery

modalities.

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This announcement is made by the Company on a voluntary basis. There is no

guarantee that the Company will be able to develop, or ultimately market, STP705, successfully. Shareholders and potential investors of the Company should exercise caution and due care when dealing in the shares of the Company.

By order of the Board

Sirnaomics Ltd. Dr. Poon Hung Fai Chairman and Executive Director

Hong Kong, July 30, 2026