SHANGHAI and HONG KONG, July 28, 2025 -- Antengene Corporation Limited ("Antengene", SEHK: 6996.HK), a leading innovative, commercial-stage global biopharmaceutical company dedicated to discovering, developing and commercialising first-in-class and/or best-in-class medicines for cancer, today announced that an abstract featuring the latest data from a Phase I/II study of the Claudin 18.2 antibody-drug conjugate (ADC), ATG-022, has been accepted for poster presentation at the 2025 European Society for Medical Oncology Annual Congress (ESMO 2025), taking place from October 17th to October 21st at the Messe Berlin in Berlin, Germany.

Details of the Poster Presentation:

ATG-022 (Claudin 18.2 antibody-drug conjugate)
Title: Phase I/II study of Claudin 18.2 ADC ATG-022 in patients with advanced gastric/ gastroesophageal junction cancer (CLINCH)
Abstract Number: 2907
Presentation Number: 2113P
Date: October 19, 2025

About ATG-022

ATG-022 is an antibody-drug conjugate (ADC) designed to target CLDN18.2, a member of the Claudin family of cell adhesion molecules. Under normal conditions, Claudins are located within tight junctions between cells, forming a barrier to regulate cell permeability. However, in cancer, Claudins are aberrantly expressed on the cell surface due to changes in cell polarity. CLDN18.2 is frequently overexpressed in a range of primary malignant tumors, including gastric, esophageal, cholangiocarcinoma, and pancreatic cancers. The U.S. Food and Drug Administration (FDA) has awarded Orphan Drug Designations to ATG-022, for gastric and pancreatic cancers.

Data from the ongoing CLINCH study demonstrated that ATG-022 delivers robust efficacy across all levels of CLDN18.2 expression in gastric cancer patients, including those with high, low, and ultra-low expression. This broad activity positions ATG-022 as a potential market leader, capable of addressing the largest patient population with CLDN18.2-positive tumors. Furthermore, the strong efficacy observed in patients with low CLDN18.2 expression suggests promise for treating other tumor types with similar expression profiles.

About Antengene

Antengene Corporation Limited ("Antengene", SEHK: 6996.HK) is a leading commercial-stage R&D-driven global biopharmaceutical company focused on the discovery, development, manufacturing and commercialization of innovative first-in-class/best-in-class therapeutics for the treatment of hematologic malignancies and solid tumors, in realizing its vision of "Treating Patients Beyond Borders".

Antengene has built a pipeline of 9 oncology assets at various stages going from clinical to commercial, including 6 with global rights, and 3 with rights for the APAC region. To date, Antengene has obtained 31 investigational new drug (IND) approvals in the U.S. and Asia, and submitted new drug applications (NDAs) in 11 Asia Pacific markets, with the NDA for XPOVIO^® (selinexor) already approved in Mainland of China, Taiwan China, Hong Kong China, Macau China, South Korea, Singapore, Malaysia, Thailand, Indonesia and Australia.

Forward-looking statements

The forward-looking statements made in this article relate only to the events or information as of the date on which the statements are made in this article. Except as required by law, we undertake no obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events or otherwise, after the date on which the statements are made or to reflect the occurrence of unanticipated events. You should read this article completely and with the understanding that our actual future results or performance may be materially different from what we expect. In this article, statements of, or references to, our intentions or those of any of our Directors or our Company are made as of the date of this article. Any of these intentions may alter in light of future development. For a further discussion of these and other factors that could cause future results to differ materially from any forward-looking statement, please see the other risks and uncertainties described in the Company's Annual Report for the year ended December 31, 2024, and the documents subsequently submitted to the Hong Kong Stock Exchange.

For more information, please contact:

Investor Contacts:
Donald Lung
E-mail: Donald.Lung@antengene.com
Mobile: +86 18420672158

PR Contacts:
Peter Qian
E-mail: Peter.Qian@antengene.com
Mobile: +86 13062747000