Approval of Phase I/II Clinical Trial of ATG-016 (Eltanexor), a Second Generation Selective Inhibitor of Nuclear Export (SINE), in Mainland China for the Treatment of Myelodysplastic Syndrome

Antengene Corporation Limited, a leading innovative biopharmaceutical company dedicated to discovering, developing and commercializing global first-in-class and/or best-inclass therapeutics in hematology and oncology, announced that the National Medical Products Administration (NMPA) has approved the clinical trial of ATG-016 (eltanexor) in patients with intermediate and higher risk myelodysplastic syndrome (MDS) according to the Revised International Prognostic Scoring System (IPSS-R) after the failure of hypomethylating agents (HMA) based therapy. The trial is a Phase I/II, single-arm, open-label clinical study, aiming to evaluate the pharmacokinetics, safety and efficacy of ATG-016 (eltanexor) monotherapy.

MDS is a heterogeneous group of clonal disorders of the bone marrow hematopoietic stem cells (HPSCs), characterized by ineffective hematopoiesis with peripheral blood cytopenia and a higher risk for developing acute myeloid leukemia (AML). Patients with high-risk MDS refractory to hypomethylating agents have a median overall survival (OS) of only 4 to 6 months with limited options for follow-up treatment. Pre-clinical studies have demonstrated that selective inhibitor of nuclear export (SINE) compounds are able to block the nuclear export of many tumor suppressor proteins (e.g. p53, IkB, p21) leading to their accumulation and activation in the nucleus thereby exerting anti-tumor effects. In addition, SINE compounds can also reduce the nuclear export and translation of many oncogenic mRNA (c-Myc, Bcl-2, Bcl-6, cyclin D) which are bound to elF4E and result in selective apoptosis of tumor cells. ATG-016 is a member of the latest-generation of SINE compounds. Compared to the first-generation nuclear export inhibitor, ATG-016 demonstrates minimal blood-brain barrier permeability and a broader therapeutic window. It has shown preliminary anti-cancer activity in high-risk MDS patients.

Dr. Jay Mei, the Founder, Chairman and CEO of Antengene expressed, "The approval of the ATG-016 clinical trial demonstrates the efficient execution of the Antengene R&D team and is also the first clinical trial approval obtained by Antengene in mainland China after its listing." He also mentioned, "Selinexor, the first-generation selective inhibitor of nuclear export, has shown extensive activity against hematological malignancies and solid tumors, and has been approved by the FDA for relapsed/refractory multiple myeloma and diffuse large B-cell lymphoma. As a second-generation orally available SINE compound, ATG-016 can reduce the blood-brain barrier penetration, thereby representing a broader therapeutic window with potentially less adverse events and better drug tolerability."

About ATG-016

ATG-016 (eltanexor) is a second-generation selective inhibitor of nuclear export compound. Compared to the first-generation SINE compound, ATG-016 has lower blood-brain barrier penetration and broader therapeutic window which allows more frequent dosing and a longer period of exposure at higher levels with better tolerability. Therefore, ATG-016 may be used to target a wider range of indications. We plan to conduct phase I/II clinical studies for MDS in China, and plan to further develop ATG-016 for cancers with high prevalence in the Asia-Pacific region (such as KRAS-mutant solid tumors) and virus infection related malignancies (such as nasopharyngeal carcinoma).

About Antengene

Antengene Corporation Limited ("Antengene", SEHK: 6996.HK) is a leading clinical-stage Asia-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, obtained 10 investigational new drug (IND) approvals and has 9 ongoing cross-regional clinical trials in Asia Pacific. At Antengene, we focus on developing drug candidates with novel mechanisms of action (MoAs) and first-in-class/best-in-class potential to address significant unmet medical needs. The vision of Antengene is to "Treat Patients Beyond Borders" through research, development and commercialization of first-in-class/best-in-class therapeutics.