Antengene : VOLUNTARY ANNOUNCEMENT NMPA APPROVAL OF IND APPLICATION FOR ATG-019 IN PATIENTS WITH ADVANCED SOLID TUMORS OR NON-HODGKIN'S LYMPHOMA

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Antengene Corporation Limited

德琪醫藥有限公司

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 6996)

VOLUNTARY ANNOUNCEMENT

NMPA APPROVAL OF IND APPLICATION FOR ATG-019 IN PATIENTS WITH ADVANCED SOLID TUMORS OR NON-HODGKIN'S LYMPHOMA

Antengene Corporation Limited (the "Company", together with its subsidiaries, the "Group") hereby informs the shareholders and potential investors of the Company of the attached press release that the Company has received the approval of the investigational new drug ("IND") application by the National Medical Products Administration ("NMPA") for a Phase I clinical trial to evaluate safety and tolerability of ATG-019 (monotherapy or combined with niacin ER) in patients with advanced solid tumors or non-Hodgkin's lymphoma in China.

This is a voluntary announcement made by the Company. The Group cannot guarantee that ATG-019 will ultimately be successfully developed and marketed. Shareholders and potential investors of the Company are advised to exercise caution when dealing in the shares of the Company.

By order of the Board

Antengene Corporation Limited

Dr. Jay Mei

Chairman

Hong Kong, April 7, 2021

As at the date of this announcement, the board of directors of the Company comprises Dr. Jay Mei, Mr. John F. Chin and Mr. Yiteng Liu as executive directors; Mr. Yanling Cao, Mr. Zhen Li and Dr. Kan Chen as non-executive directors; and Mr. Mark J. Alles, Ms. Jing Qian and Mr. Sheng Tang as independent non-executive directors.

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Antengene Announces NMPA Approval of IND Application for ATG-019 in Patients with Advanced Solid Tumors or Non-Hodgkin's Lymphoma

Shanghai and Hong Kong, PRC, April 6, 2021 - Antengene Corporation Limited ("Antengene", SEHK: 6996.HK), a leading innovative biopharmaceutical company dedicated to discovering, developing and commercializing global first-in-class and/or best-in class therapeutics in hematology and oncology, today announced that the National Medical Products Administration (NMPA) has approved the Investigational New Drug (IND) application for a Phase I clinical trial to evaluate safety and tolerability of ATG-019(monotherapy or combined with niacin ER) in patients with advanced solid tumors or non-Hodgkin'slymphoma (NHL) in China.

As an orally bioavailable dual PAK4/NAMPT inhibitor, ATG-019can lead to antitumor effects through energy depletion, inhibition of DNA repair, cell cycle arrest, inhibition of proliferation, and ultimately cell apoptosis. Hematological and solid tumor cells that are dependent on both PAK4 and NAMPT pathways may be susceptible to single-agent anti-tumoractivity by ATG-019. ATG-019has clear preclinical anti-tumoractivity and a superior pharmacokinetics (PK) and safety profile making it an attractive novel drug candidate. Antengene has recently been conducting a

Phase I clinical trial (TEACH) of ATG-019 in advanced solid tumors and NHL in Taiwan.

"The NMPA's approval of the IND application for ATG-019 indicates the potential of this drug to be applied to Chinese patients. We look forward to initiating the first clinical trial of ATG-019 in mainland China," said Dr. Jay Mei, Founder, Chairman and CEO of Antengene. "ATG-019 is an orally available dual PAK4/NAMPT inhibitor that achieves synergistic antitumor effects through the co-inhibition of the two pathways. We believe that ATG-019, as a novel agent under investigation, can potentially provide an additional treatment option for patients with advanced solid tumor and NHL."

About ATG-019

ATG-019 is a global first-in-class oral dual PAK4/NAMPT inhibitor developed by Karyopharm Therapeutics Inc. (NASDAQ: KPTI). Antengene reached an exclusive agreement of cooperation and authorization with Karyopharm and obtained the exclusive development and commercialization rights of ATG-019 in multiple Asia-Pacific markets, including Greater China, South Korea, Australia, New Zealand and ASEAN countries.

PAK4 is a signaling protein regulating numerous fundamental cellular processes, including intracellular transport, cellular division, cell shape and motility, cell survival, immune defense and the development of cancer. PAK4 interacts with many key signaling molecules involved in cancer development such as beta-catenin, CDC42, Raf-1, BAD and myosin light chain. NAMPT is a pleiotropic protein with intra- and extra-cellular functions as an enzyme, cytokine, growth factor, and hormone that can be found in a complex with PAK4 in the cell. In preclinical mouse models,

ATG-019 in combination with anti-PD-1 therapies showed improved antitumor efficacy over anti-PD-1 monotherapy, indicating the potential of the combined therapy to treat anti-PD-1 resistant patients.

Antengene is conducting a Phase I clinical trial of ATG-019 in Taiwan in patients with advanced NHL and solid tumors and are planning to conduct clinical trials exploring its combination potential with other agents.

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About Antengene

Antengene Corporation Limited ("Antengene", SEHK: 6996.HK) is a leading clinical-stageAsia-Pacific biopharmaceutical company focused on innovative oncology medicines. Antengene aims to provide the most advanced anti-cancer drugs to patients in China, the Asia Pacific Region, and around the world. Since its establishment, Antengene has built a pipeline of 12 clinical and pre-clinical stage assets and obtained 13 investigational new drug approvals in Asia Pacific. The vision of Antengene is to "Treat Patients Beyond Borders". Antengene aims to address significant unmet medical needs by discovering, developing, and commercializing first-in-class/best-in-class therapeutics.

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.

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