HANSOH PHARMA - VOLUNTARY ANNOUNCEMENT - RISVUTATUG REZETECAN FOR INJECTION (HS-20093) FOR SMALL CELL LUNG CANCER INCLUDED IN PRIORITY REVIEW AND APPROVAL PROCEDURE OF THE NMPA

Hansoh Pharmaceutical Group Company Limited

翰森製藥集團有限公司

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 3692)

VOLUNTARY ANNOUNCEMENT

RISVUTATUG REZETECAN FOR INJECTION (HS-20093) FOR SMALL CELL LUNG CANCER INCLUDED IN PRIORITY REVIEW AND

APPROVAL PROCEDURE OF THE NMPA

The board of directors (the "Board") of Hansoh Pharmaceutical Group Company Limited (the "Company" and together with its subsidiaries, the "Group") is pleased to announce that, on August 21, 2026, based on the positive results from the pivotal Phase III ARTEMIS-008 trial on risvutatug rezetecan for injection (HS-20093) (the "Product"), the indication for small cell lung cancer (SCLC) after the failure of prior platinum-based chemotherapy of the Product has been included in the Priority Review and Approval Procedure of the National Medical Products Administration (the "NMPA").

By Order of the Board

Hansoh Pharmaceutical Group Company Limited Zhong Huijuan

Chairlady

Hong Kong, September 11, 2026