Suzhou, China, April 17, 2023 - Alphamab Oncology (stock code: 9966.HK) announced that the preclinical result of KN052 (PD-L1/OX40 bispecific antibody) were presented as a poster at the Late-Breaking Research session of the AACR Annual Meeting 2023 (AACR 2023).

The AACR Annual Meeting is the largest cancer meeting in the world, gathering high-quality oncology research and clinical progress all over the world every year. Late-Breaking Research is a high-profile session of the AACR Annual Meeting, which mainly showcases the most innovative and clinical potential research in the field of cancer treatment. KN052 is a PD-L1/OX40 bispecific antibody developed in-house by Alphamab Oncology, and is the world's first PD-L1/OX40 bispecific antibody entering clinical study. The poster is presented on April 16 (EST), and available from the company's website: www.alphamabonc.com.

Title: KN052, a Novel PD-L1/OX40 Bispecific Antibody, Exhibits Potent Antitumor Efficacy

Session Title: Late-Breaking Research: Experimental and Molecular Therapeutics

Presentation Format: Poster

Location: Poster Section 35

Poster Board Number: 13

KN052 has acceptable pharmacokinetics and safety, and its antitumor activity is significantly stronger than that of the two single-target control antibodies used alone and in combination.

●      KN052 displayed high affinity binding to human PD-L1 and OX40 with KD of 2.38E-09M and 1.19E-08M. It can simultaneously bind PD-L1 and OX40, effectively block PD-L1 and PD-1/CD80 pathway and activate OX40 pathway. Additionally, there is synergy between blocking effect and activation effect.

●      The single dose pharmacokinetics study indicated that KN052 has general linear dynamic characteristics, and pharmacokinetics parameters show no significant differences between males and females in the range 3-30 mg/kg.

●      In MC38 and MCA205 animal models，tumor inhibition rate of KN052 at 3 mg/kg and 15 mg/kg was respectively，and has long term antitumor efficacy.

●      The HNSTD of KN052 was determined at 30mg/kg in cynomolgus monkeys, KN052 showed good safety profile at any dose levels.

●      KN052 is currently in phase I investigation and preliminary result is expected to be obtained in 2023.

About KN052

KN052 is a PD-L1/OX40 bispecific antibody developed in-house by Alphamab Oncology. It can simultaneously bind PD-L1 and OX40, effectively block the PD-L1/PD-1 pathway and activate OX40 pathway. KN052 is being studied in Phase I clinical trial in China.

About Alphamab Oncology

Alphamab Oncology is a leading biopharmaceutical company dedicated to the discovery, development manufacturing and commercialization of world-class innovative biotherapeutics for cancer treatment. On December 12, 2019, Alphamab Oncology was listed on the Main Board of Hong Kong Stock Exchange, with the stock code:9966.

We have converged a professional R&D team led by top scientists, and have a complete industrial chain from early research and development of innovative drugs, process development, commercial production to clinical research.

With multiple in-house proprietary platforms of bispecifics, protein engineering and antibody screening, Alphamab Oncology has established a globally competitive and differentiated pipeline which consists of tumor monoclonal antibodies, bispecific antibodies, and antibody-drug conjugates. Among them, 2 varieties were selected into the national special project of " New Drug Development", and 3 varieties were granted 4 orphan drug qualifications by FDA. The world's first subcutaneous PD-L1 inhibitor injection (Envafolimab) has been obtained the market approval by the Chinese National Medical Products Administration. More than 30 clinical studies have been carried out in 6 varieties in China, the United States and Australia, among which 8 studies of 3 varieties have entered the critical clinical stage in China and the United States.

To make cancer manageable and curable，Alphamab Oncology has always been guided by clinical value and patient needs, and focuses on the development of innovative, safe and affordable anti-tumor drugs to benefit patients in China and around the world.

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