Antengene Announces the Acceptance of ATG-010 (Selinexor) NDA by the NMPA for the Treatment of rrMM

Antengene Corporation Limited, 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, announced that the National Medical Products Administration (NMPA) accepted its New Drug Application (NDA) for ATG-010 (Selinexor, XPOVIO®), a first-in-class oral selective inhibitor of nuclear export (SINE) compound, for the treatment of patients with relapsed/refractory multiple myeloma (rrMM). This is the fifth NDA for ATG-010 submitted by Antengene, after the four NDAs recently submitted in Australia, South Korea, Singapore and Hong Kong, S.A.R., China, China in the Asia Pacific region, and also the first NDA of SINE compounds in mainland China, a step closer to providing a novel option to Chinese patients diagnosed with hematological malignancies.

Antengene has recently submitted NDAs in multiple markets for ATG-010 across three indications for multiple myeloma and diffuse large B-cell lymphoma. Recently, the National Comprehensive Cancer Network (NCCN®) has also added five ATG-010 regimens to its guidelines for multiple myeloma or diffuse large B-cell lymphoma. ATG-010 is the first approved SINE compound in the world. It induces the apoptosis of cancer cells in vitro and in vivo by causing the nuclear storage and activation of tumor suppressor proteins and other growth-regulating proteins, and by down-regulating the intracytoplasmic levels of various oncogenic proteins while normal cells are not affected. Clinical studies have demonstrated that ATG-010 has clinical effects in multiple types of hematological and solid tumors with manageable safety profile.

"We are delighted to see the acceptance of the NDA submission in China for ATG-010 in rrMM, which marks another important milestone and one step closer to bringing ATG-010 to patients in China." said Dr. Jay Mei, M.D., Ph.D., Founder, Chairman and CEO of Antengene. "In addition to its effectiveness in hematological malignancies, there are several clinical trials in multiple solid tumor indications with ATG-010 including a global Phase 3 trial in endometrial cancer (SIENDO) and a Phase 3 trial in liposarcoma (SEAL) which have shown encouraging results. We continue to prepare to commercialize ATG-010 in China and across the APAC region so that cancer patients can benefit from this novel cancer medicine."

About ATG-010 (selinexor, XPOVIO®)

ATG-010 (selinexor, XPOVIO®), a first-in-class and only-in-class oral selective inhibitor of nuclear export (SINE) compound discovered and developed by Karyopharm Therapeutics Inc. (NASDAQ: KPTI), is currently being developed by Antengene, which has the exclusive development and commercial rights in certain Asia-Pacific markets, including Greater China, South Korea, Australia, New Zealand and the ASEAN countries.

In July 2019, the US Food and Drug Administration (FDA) approved selinexor (XPOVIO®) in combination with low-dose dexamethasone for the treatment of relapsed/refractory multiple myeloma (rrMM) and in June 2020 approved selinexor (XPOVIO®) as a single-agent for the treatment of relapsed/refractory diffuse large B-cell lymphoma (rrDLBCL). In December 2020, selinexor (XPOVIO®) also received FDA approval as a combination treatment for multiple myeloma after at least one prior therapy. A Marketing Authorization Application (MAA) has also been submitted to the European Medicines Agency (EMA) with a request for conditional approval of selinexor in this same rrMM indication. Selinexor (XPOVIO®) is so far the first and only oral SINE compound approved by the FDA and is the first drug approved for the treatment of both MM and DLBCL. Selinexor (XPOVIO®) is also being evaluated in several other mid-and later-phase clinical trials across multiple solid tumor indications, including liposarcoma and endometrial cancer. In November 2020, at the Connective Tissue Oncology Society 2020 Annual Meeting (CTOS 2020), Antengene's partner, Karyopharm, presented positive results from the Phase 3 randomized, double blind, placebo controlled, cross-over SEAL trial evaluating single agent, oral selinexor (XPOVIO®) versus matching placebo in patients with liposarcoma. Karyopharm also announced that the ongoing Phase 3 SIENDO trial of selinexor (XPOVIO®) in patients with endometrial cancer passed the planned interim futility analysis and the Data and Safety Monitoring Board (DSMB) recommended the trial should proceed as planned without any modifications. Top-line SIENDO trial results are expected in the second half of 2021.

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 and obtained 12 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