Antengene To Present One Oral and Four Abstracts at ASCO 2024

Oral Presentation：a Phase II study of ATG-008 (mTORC1/2 Inhibitor) combined with PD-1 antibody in patients with cervical cancer

Three Poster presentations: Phase I/II studies of ATG-031 (anti-CD24 monoclonal antibody),ATG-022 (Claudin 18.2 antibody-drug conjugate),and selinexor (XPO1 Inhibitor)

Journal Publication: the first-in-human Phase I dose-escalation study of ATG-017 (ERK1/2 inhibitor) in patients with advanced solid tumors

SHANGHAI and HONG KONG,May 24,2024 -- 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 announcedone oral presentation,three poster presentations and a journal publication at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting,taking place from May 31st to June 4th at the McCormick Place Convention Center in Chicago,IL,the United States.

Details of the Oral Presentation:

ATG-008 (mTORC1/2 Inhibitor)

Title: A phase I/II study of the TORC1/2 inhibitor onatasertib combined with toripalimab in patients with advanced solidtumors: Cervical cancer cohort

Abstract: 5509

Session: Clinical Science Symposium – Stronger Together: Novel Combinations Across the Gynecologic Cancer Spectrum

Date: June 1,2024

Time: 1:15 PM - 2:45 PM (Central Daylight Time)

2:15 AM - 3:45 AM,June 2,2024 (Beijing Time)

31 checkpoint inhibitor (CPI)-naïve cervical cancer patients who previously had at least one systemic line of chemotherapy were enrolled in the TORCH-2 study as of Oct 20th 2023.

ATG-008 (Onatasertib; oral TORC1/2 inhibitor) combined with toripalimab (anti-PD-1 antibody) showed promising anti-tumor activity and acceptable tolerability in cervical cancer patients,achieving an overall response rate (ORR) of 53.3% and a disease control rate of 86.7%.

In general,ATG-008 in combination with toripalimab are very well tolerated. The most common grade ≥ 3 treatment-related adverse events (TRAEs) included rash (12.9%),decreased lymphocyte count (9.7%),and decreased platelet count (6.5%).

Encouraging response rates and disease stabilization were observed in patients,regardless of PD-L1 expression,with further data being collected in an ongoing expansion cohort for CPI-treated cervical cancer.

Details of the Poster Presentations:

ATG-031 (anti-CD24 monoclonal antibody)

Title: A first-in-human phase I study of ATG-031,anti-CD24 antibody,in patients with advanced solid tumors or B-cell non-Hodgkin lymphomas (PERFORM)

Abstract: TPS2691

Session: Developmental Therapeutics—Immunotherapy

Date: June 1,2024

Time: 9:00 AM - 12:00 PM (Central Daylight Time)

10:00 PM,June 1 - 1:00 AM,2024 (Beijing Time)

ATG-031 is a first-in-class CD24 antibody that promotes cancer cell phagocytosis and T cell activity by disrupting the CD24-Siglec-10 interaction on macrophages,while also triggering antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC).

The Phase I PERFORM study is designed to evaluate the safety and preliminary efficacy of ATG-031 in patients with advanced solid tumors or B-cell non-Hodgkin's lymphoma,employing a dose-escalation phase with a Bayesian Optimal Interval (BOIN) design and a dose-expansion phase with two or more dose levels to determine the recommended phase II dose (RP2D).

As of April 2024,the study is underway in 4 U.S. sites,and the first dose level has been cleared.

ATG-022 (Claudin 18.2 Antibody-drug Conjugate)

Title: An open-label,multicenter,phase I study of ATG-022 in patients with advanced/metastatic solid tumors (CLINCH)

Abstract: 3032

Session: Developmental Therapeutics—Molecularly Targeted Agents and Tumor Biology

Date: June 1,2024

Time: 9:00 AM - 12:00 PM (Central Daylight Time)

10:00 PM,2024 (Beijing Time)

ATG-022 is a Claudin 18.2 (CLDN 18.2)-targeting antibody-drug conjugate (ADC) with sub-nM high affinity that showed promising tumor inhibition activity in vitro and in vivo. The CLINCH Phase I trial is assessing its safety,tolerability,and efficacy in patients with advanced/metastatic solid tumors.

As of October 9th,2023,10 patients have been enrolled,receiving doses ranging from 0.3 to 2.4 mg/kg. The most common grade ≥ 3 TRAEs included nausea,vomiting,and decreased appetite,each occurring in 30% of patients. No dose-limiting toxicities (DLTs) were reported.

Preliminary efficacy data among 7 gastric cancer patients across multiple doses in the Phase I dose escalation demonstrated one complete response (CR) in a patient with gastric cancer (2.4 mg/kg,CLDN 18.2-negative) and one partial response (PR) in another patient (1.8 mg/kg,CLDN 18.2 expression undetermined). ATG-022 demonstrated tolerability,safety,and potential anti-tumor activity. A Phase II trial is currently enrolling patients with gastric cancer and other solid tumors.

Selinexor (XPO1 Inhibitor)

Title: Selinexor combined with tislelizumab in patients with relapsed or refractory extranodal NK/T-cell lymphoma (R/R ENKTL): Results of dose-escalation of cohort C,from a multicenter,single-arm,phase I/II study (TOUCH)

Abstract: 7065

Session: Hematologic Malignancies—Lymphoma and Chronic Lymphocytic Leukemia

Date: June 3,June 3 - 1:00 AM,June 4,2024 (Beijing Time)

The Phase I/II TOUCH study is investigating selinexor combined with different drugs in relapsed/refractory extranodal NK/T-cell lymphoma (R/R ENKTL). Cohort C of the study aims to evaluate the safety,tolerability and preliminary efficacy of selinexor in combination with anti-PD-1 antibody tislelizumab.

As of December 25th,12 patients were enrolled,with no DLTs observed,and the maximum tolerated dose (MTD) was not reached. The most common adverse events included asthenia,neutropenia,and nausea/vomiting. Grade ≥ 3 adverse events occurred in 58.3% of patients.

The ORR was 72.7% among 11 efficacy evaluable patients,including a CR rate of 36.4%. The combination showed a tolerable safety profile and promising efficacy.

Details of the Journal Publication:

ATG-017 (ERK1/2 Inhibitor)

Title: Results of a first-in-human,dose-escalation phase I study of the ERK1/2 inhibitor ATG-017 in patients with advanced solid tumors

Abstract: e15114

Session: Publication Only: Developmental Therapeutics – Molecularly Targeted Agents and Tumor Biology

ATG-017,an oral and selective ERK1/2 inhibitor,was evaluated in a Phase I study to assess safety,pharmacokinetics,and MTD in patients with refractory advanced solid tumors.

At the 20 mg BID level,no DLTs were observed,and pharmacokinetic analysis revealed effective ERK inhibition at this dose. Common treatment-emergent adverse events (TEAEs) were consistent with previously reported toxicities with other ERK pathway inhibitors (gastrointestinal,skin,and ocular adverse events).

Efficacy data showed that one patient (4.8%) achieved a PR,while 8 patients (38%) achieved stable disease (SD).

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 pipeline of 9 oncology assets at various stages going from clinical to commercial,including 6 with global rights,and 3 with rights for the APAC region. To date,Antengene has obtained 29 investigational new drug (IND) approvals in the U.S. and Asia,and submitted 10 new drug applications (NDAs) in multiple Asia Pacific markets,with the NDA for XPOVIO® (selinexor) already approved in Mainland of China,Taiwan China,Hong Kong China,Macau China,South Korea,Singapore and Australia.

Forward-looking statements

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For more information,please contact:

Investor Contacts:

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