Antengene Announces Clinical Trial Collaboration with BeiGene to Evaluate Selinexor in Combination with Tislelizumab in T and NK-Cell Lymphoma

- Selinexor is an oral small molecule XPO1 inhibitor; tislelizumab is an anti-PD-1 checkpoint inhibitor

SHANGHAI and HONG KONG,June 27,2022 -- 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 therapeutics in hematology and oncology,today announced that it has entered intoa clinical trial collaboration with BeiGene to evaluate the safety,pharmacokinetics,pharmacodynamics and preliminary efficacy of selinexor in combination with BeiGene's anti-PD-1 checkpoint inhibitor,tislelizumab. This multi-center,open-label Phase I/II trial will evaluate the investigational combination as a potential treatment option for patients with T and NK-cell lymphoma.

"We are delighted to partner with BeiGene,a company that strives for innovation and excellence,and is committed to developing best-in-class or first-in-class anti-cancer therapies for patients across the globe. These qualities are very similar to those of our vision at Antengene," said Dr. Jay Mei,Antengene's Founder,Chairman and CEO. "We look forward to advancing the combination of selinexor and tislelizumab to clinical development. With good data we will be able to bring this treatment regimen to patients with T and NK-cell lymphoma,diseases that are endemic in Asia but underserved by current therapies."

"At Antengene,we believe that the combinational use of immuno-oncology drugs and Selective Inhibitor of Nuclear Export (SINE) compounds possesses huge potential as novel treatment regimens for cancer patients," said Dr. Kevin Lynch,Antengene's Chief Medical Officer. "The mechanism of action of selinexor in inhibiting the nuclear export protein XPO1 facilitates the intranuclear accumulation of tumor suppressors,making it a good partner in multiple combination treatment regimens. Preclinical research we conducted demonstrated that selinexor combined with a checkpoint inhibitor increased anti-tumor activity in multiple tumor models. In addition,deep and durable responses were also seen in multiple case reports of patients with T and NK-cell lymphoma treated with selinexor in combination with an anti-PD-1 checkpoint inhibitor. We hope to confirm that selinexor can synergize with tislelizumab to deliver an effective treatment regimen and help address the huge unmet medical needs in T and NK-cell lymphoma in the Asia Pacific regions and around the world." continued Dr. Lynch.

Tislelizumab is a PD-1 inhibitor designed to help aid the body's immune cells to detect and fight tumors. Tislelizumab,a humanized monoclonal antibody,is specifically designed to minimize binding to FcγR on macrophages. In pre-clinical studies,binding to FcγR on macrophages has been shown to compromise the anti-tumor activity of PD-1 antibodies through activation of antibody-dependent macrophage-mediated killing of T effector cells.

About T and NK-Cell Lymphoma

T and NK-cell lymphoma is a set of heterogeneous diseases,accounting for 25-30% of Non-Hodgkin Lymphoma (NHL) cases in China and only about 10% in USA and Europe. There has been little improvement in the past decade when compared to B-cell Non-Hodgkin Lymphoma (B-NHL) as 5-year overall survival rate was only 30% in most common subtypes[1]. The unmet medical needs remain as agents with new mechanism of action to be explored and possibility to improve the treatment paradigm for the disease.

About the 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 exclusive development and commercialisation rights from Karyopharm Therapeutics Inc. (Nasdaq: KPTI) to these three compounds in certain APAC markets.

About XPOVIO® (Selinexor)

XPOVIO® is the world's first approved orally-available,selective inhibitor of the nuclear export protein XPO1. It offers a novel mechanism of action,synergistic effects in combination regimens,fast onset of action,and durable responses.

By blocking the nuclear export protein XPO1,XPOVIO® can promote the intranuclear accumulation and activation of tumor suppressor proteins and growth regulating proteins,and down-regulate the levels of multiple oncogenic proteins. XPOVIO® delivers its antitumor effects through three mechanistic pathways: 1) exerting antitumor effects by inducing the intranuclear accumulation of tumor suppressor proteins; 2) reducing the level of oncogenic proteins in the cytoplasm by inducing the intranuclear accumulation of oncogenic mRNAs; and 3) restoring hormone sensitivity by activating the glucocorticoid receptors (GR) pathway. To utilize its unique mechanism of actions,XPOVIO® is being evaluated for use in multiple combination regimens in a range of indications. At present,Antengene is conducting 10 clinical studies of XPOVIO® in mainland China for the treatment of relapsed/refractory hematologic malignancies and solid tumors (3 of these studies are being jointly conducted by Antengene and Karyopharm Therapeutics Inc. [Nasdaq:KPTI]).

XPOVIO® is approved in South Korea for two indications:

In combination with dexamethasone for the treatment of adult patients with relapsed or refractory multiple myeloma (R/R MM) who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors,at least two immunomodulatory agents,and an anti-CD38 monoclonal antibody.

As a monotherapy for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL),not otherwise specified,including DLBCL arising from follicular lymphoma,after at least 2 lines of systemic therapy.

XPOVIO® is approved in mainland China for one indication:

In combination with dexamethasone for the treatment of adult patients with relapsed or refractory multiple myeloma (R/R MM) who have received prior therapies and whose disease is refractory to at least one proteasome inhibitor,at least one immunomodulatory agent,and an anti-CD38 monoclonal antibody.

XPOVIO® is approved in Australia for two indications:

In combination with bortezomib and dexamethasone (XVd) for the treatment of adult patients with multiple myeloma (MM) who have received at least one prior therapy.

In combination with dexamethasone (Xd) for the treatment of adult patients with relapsed or refractory multiple myeloma (R/R MM) who have received at least three prior therapies and whose disease is refractory to at least one proteasome inhibitor (PI),at least one immunomodulatory agent (IMiD),and an anti-CD38 monoclonal antibody (mAb).

XPOVIO® is approved in Singapore for three indications:

In combination with bortezomib and dexamethasone for treatment of adult patients with multiple myeloma (MM) who have received at least one prior therapy.

In combination with dexamethasone for the treatment of adult patients with relapsed or refractory multiple myeloma (R/R MM) who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors,after at least 2 lines of systemic therapy who are not eligible for haematopoietic cell transplant.

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".

Since 2017,Antengene has built a broad and expanding pipeline of 15 clinical and preclinical assets,of which 10 are global rights assets,and 5 came with rights for Asia Pacific markets including the Greater China region. To date,Antengene has obtained 24 investigational new drug (IND) approvals in the U.S. and Asia,and submitted 6 new drug applications (NDAs) in multiple Asia Pacific markets,with the NDA for XPOVIO® (selinexor) already approved in mainland China,South Korea,Singapore and Australia.

About BeiGene

BeiGene is a global,science-driven biotechnology company focused on developing innovative and affordable medicines to improve treatment outcomes and access for patients worldwide. With a broad portfolio of more than 40 clinical candidates,we are expediting development of our diverse pipeline of novel therapeutics through our own capabilities and collaborations. We are committed to radically improving access to medicines for two billion more people by 2030. BeiGene has a growing global team of over 8,000 colleagues across five continents. To learn more about BeiGene,please visit www.beigene.com and follow us on Twitter at @BeiGeneGlobal.

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,see the section titled "Risk Factors" in our periodic reports filed with the Hong Kong Stock Exchange and the other risks and uncertainties described in the Company's Annual Report for year-end December 31,2021,and subsequent filings with the Hong Kong Stock Exchange.

References:

1. Armitage JO. The aggressive peripheral T-cell lymphomas: 2017. Am J Hematol. 2017 Jul;92(7):706-715

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