Antengene Announces IND Approval in China for a Phase II Study of Eltanexor (ATG-016) in Patients with High-Risk Myelodysplastic Syndromes

This study is the third ATG-016 study to be conducted in China.

Study highlights Antengene's robust SINE programs.

SHANGHAI and HONG KONG,March 30,2022 -- Antengene Corporation Limited ("Antengene" SEHK: 6996.HK),a leading innovative,commercial-stage global biopharmaceutical company dedicated to discovering,developing and commercializing first-in-class and/or best-in-class medicines for cancer,today announced the China National Medical Products Administration (NMPA) has approved a Phase II open-label study designed to evaluate the safety,tolerability and efficacy of the next-generation selective inhibitor of nuclear export (SINE) compound ATG-016 in patients with high-risk myelodysplastic syndromes (MDS).

ATG-016 is being developed for treating patients with MDS or solid tumors. ATG-016 and other SINE compounds inhibit the nuclear export protein called Exportin 1 (XPO1) that helps cancers grow by removing tumor suppressor proteins from the nucleus.ATG-016 is an orally-active,highly-specific next-generation XPO1 inhibitor with an improved pharmacological profile versus the first novel SINE compound,ATG-010/selinexor/XPOVIO®. These attributes can potentially enable more frequent dosing and a better tolerated dosing regimen.

"Antengene is dedicated to bringing first-in-class medicines to people in China and beyond,with a special focus on resistant and advanced cancers. We are the first company in the Asia Pacific Region with a SINE program. Our eltanexor program is comprised of three studies in mainland China,to evaluate ATG-016 in patients with advanced MDS and solid tumors." said Dr. Jay Mei,Antengene's Founder,Chairman and CEO. "We are encouraged by activity seen with this drug in the previously reported eltanexor data from a Phase I study in MDS patients and eager to advance this study,with the goal of benefiting patients in China with high-risk MDS."

The KCP-8602-801 trial is an on-going open-label Phase I/II study initiated by Karyopharm Therapeutics Inc. ("Karyopharm") to evaluate the safety,tolerability,and efficacy of ATG-016 in patients of 6 "Sub-parts" of relapsed/refractory cancer indications. Antengene will participate in the Part F Phase II of this study in which high-risk MDS patients will be enrolled to evaluate ATG-016 monotherapy. MDS is a malignancy originated in the bone marrow hemopoietic stem-cells of which the incidence increases significantly with age. The median overall survival (OS) of patients with intermediate,high,and very high-risk MDS are 3 years,1.6 years,and 0.8 years,respectively,and patients at these risk levels have a high probability of progressing to acute myeloid leukemia (AML). Previously,Karyopharm reported data from the Part F Phase I of the study [ATG-016 monotherapy in patients with hypomethylating agent (HMA)-refractory MDS] at the American Society of Hematology (ASH) Annual Meeting,demonstrating an overall response rate (ORR) of 53% and a median OS of 9.86 months in efficacy-evaluable patients. This compares favorably to the historical survival of four to six months for patients with HMA-refractory MDS.

About SINE Compounds

Selective Inhibitor of Nuclear Export (SINE) compounds are inhibitors of the major nuclear export protein Exportin 1 (XPO1). Currently,there are three oral SINE compounds,ATG-010 (selinexor),ATG-016 (eltanexor),and ATG-527 (verdinexor),under clinical development. Antengene has obtained the exclusive license from Karyopharm Therapeutics Inc. ("Karyopharm") to these compounds in certain APAC markets.

About Eltanexor (ATG-016)

ATG-016 and other Selective Inhibitor of Nuclear Export (SINE) compounds inhibit the nuclear export protein called Exportin 1 (XPO1) that helps cancers grow by removing tumor suppressor proteins from the nucleus. ATG-016 is an orally-active,highly-specific next-generation XPO1 inhibitor with an improved pharmacological profile and reduced brain penetration versus the first novel SINE compound,ATG-010/ selinexor/XPOVIO®. These attributes can potentially enable more frequent dosing and a better-tolerated dosing regimen. ATG-016 demonstrated preliminary anti-tumor activity in a Phase I study in advanced solid tumors and hematologic malignancies. SINE compounds also inhibit the replication of viruses that utilize XPO1 machinery. In preclinical studies,ATG-016 demonstrated an inhibitory effect on the growth of cancer induced by viruses such as Epstein Barr Virus (EBV) and Human Papilloma Virus (HPV).

Antengene is currently evaluating ATG-016 in the HATCH study,a Phase I/II registration-track study in high-risk MDS patients who have failed in hypomethylating agents-based therapies; the REACH study,a Phase I/II study in advanced solid tumors; and the KCP-8602-801 study,a multi-part open-label Phase I/II study in relapsed/refractory cancer indications initiated by Karyopharm.

ATG-016 received Orphan Drug Designation from the FDA for treatment of MDS. ATG-016 is an investigational medicine and has not been approved by the United States Food and Drug Administration or any other regulatory agency.

About Antengene

Antengene Corporation Limited ("Antengene",SEHK: 6996.HK) is a leading commercial-stage R&D-driven global biopharmaceutical company focused on innovative first-in-class/best-in-class therapeutic medicines for cancer and other life-threatening diseases. Driven by its vision of "Treating Patients Beyond Borders",Antengene aims to provide the most advanced anti-cancer drugs to patients in the Asia Pacific Region and around the world. Since initiating operations in 2017,Antengene has obtained 23 investigational new drug (IND) approvals in the US and in Asia,submitted 6 new drug applications (NDAs) in multiple Asia Pacific markets,with the NDA for selinexor/ATG-010/XPOVIO®in China,South Korea,Singapore and Australia approved. Leveraging partnerships as well as in-house drug discovery,Antengene has built a broad and expanding pipeline of 15 clinical and pre-clinical assets. Antengene has global rights on 10 programs and Asia Pacific rights,including the Greater China region,on 5 programs.

Forward-looking statements

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For more information,please contact:

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