Antengene Announces First Patient Dosed in the PROBE-CN Study of ATG-101 (PD-L1/4-1BB Bispecific Antibody) for the Treatment of Solid Tumors and Non-Hodgkin Lymphoma

ATG-101 is a novel PD-L1/4-1BB bispecific antibody. It is Antengene's first in-house developed molecule with global rights.

ATG-101 demonstrates potent in vivo efficacy in anti-PD-1/PD-L1 resistant mouse tumor models.

SHANGHAI and HONG KONG,Aug. 3,2022 --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 announcedthat the first patient has been dosed in the Phase I PROBE-CN trial to evaluate ATG-101 as a monotherapy in patients with advanced/metastatic solid tumors or B-cell non-Hodgkin lymphoma (B-NHL) in China.

Shanghai East Hospital of Tongji University is the lead site for the study,which will be conducted at four centers across China. This open-label,multicenter Phase I study is designed to assess the safety and tolerability of intravenously administered ATG-101 monotherapy in patients with advanced/metastatic solid tumors and B-NHL. The study will be conducted in two parts (dose-escalation and a dose-expansion).

ATG-101 is a novel PD-L1/4-1BB bispecific antibody that was designed to block the binding of immunosuppressive PD-1/PD-L1 and conditionally induce 4-1BB stimulation,thus activating anti-tumor immune effectors,while delivering enhanced anti-tumor activity,with an improved safety profile. In preclinical studies,ATG-101 demonstrated significant anti-tumor activity in animal models of resistant tumors as well as those that progressed on anti-PD-1/L1 treatment. Furthermore,ATG-101 has also shown an excellent safety profile in Good Laboratory Practice (GLP) toxicology studies.

"Since many patients with advanced cancer are resistant to existing chemotherapy,targeted drugs,and monoclonal antibodies or relapse in a short time after receiving treatment,there is an urgent need for innovative therapies that can improve treatment options. Increasing evidence suggests that bispecific antibodies will become a critical component of cancer therapy. We are excited to have the opportunity to collaborate with a number of prominent investigators in China to conduct the first clinical study of ATG-101,a novel PD-L1/4-1BB bispecific antibody," said Professor Ye Guo,Deputy Director of Medical Oncology at Shanghai East Hospital of Tongji University,Director of the hospital's center for Phase I trials,and principal investigator of the study. "ATG-101 has a high affinity for PD-L1 and can achieve conditional activation of 4-1BB agonist,which is expected to bring a lower risk of systemic toxicity,particularly the hepatotoxicity that has been seen with previous agonists of 4-1BB. We hope that ATG-101 will demonstrate efficacy and safety,and bring a new treatment option to patients with resistant or relapsed cancers."

"The development of novel therapies to improve and advance the care of patients with resistant,relapsed,or advanced cancers is central to Antengene's mission. Compounds that combine the well-established efficacy of inhibition of the PD-1/PD-L1 axis with activation of 4-1BB represent a fascinating opportunity in oncology. In our view,ATG-101's ability to activate exhausted T-cells and render 'cold tumors' hot has the potential to open the door to wide applicability in resistant/relapsed diseases. These qualities,together with a robust preclinical data package,position ATG-101 to be a potentially best-in-class molecule." said Dr. Kevin Lynch,Antengene's Chief Medical Officer.

About ATG-101

ATG-101 is a novel PD-L1/4-1BB bi-specific antibody being developed for the treatment of advanced/metastatic solid tumors and B-cell non-Hodgkin lymphoma (B-NHL). ATG-101 was designed to activate anti-tumor immune effectors by forming a cell-antibody-cell trimer to simultaneously block the binding of PD-L1/PD-1 and induce 4-1BB stimulation. In PD-L1 over-expressing cancer cells,ATG-101 has shown potent PD-L1 crosslinking-dependent 4-1BB agonist activity,with the potential for delivery of enhanced therapeutic efficacy whilst mitigating the risk of hepatoxicity.

Data presented at the Annual Meeting of Society for Immunotherapy in Cancer (SITC) in 2021 showed that ATG-101 was active in anti-PD-L1 resistant and relapsed tumor models. ATG-101's unique safety and efficacy properties make it a promising potential therapy for solid tumors and hematological cancers. To date,ATG-101 has received regulatory clearances in Australia,U.S.,and China to enter a Phase I clinical study for the treatment of advanced/metastatic solid tumors and NHL. The study has already been initiated in Australia and China and is in the process of initiation in the U.S.

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.

Forward-looking statements

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