I-Mab Announces Poster Presentations of 4-1BB Bispecific Antibody Portfolio at SITC 2023

ROCKVILLE,MD,U.S. and SHANGHAI,China,Nov. 1,2023 -- I-Mab (Nasdaq: IMAB) (the "Company"),a global biotechnology company focused on bringing highly differentiated medicines to patients around the world through the discovery,development,and commercialization of novel immunotherapies and biologics,today announced that two poster presentations featuring preclinical data on givastomig (also known as TJ-CD4B/ABL111) and TJ-L14B/ABL503,the Company's 4-1BB-targeting bispecific antibody assets,will be reported at the 38th Society for Immunotherapy of Cancer's (SITC) Annual Meeting,taking place November 1-5,2023,in San Diego,California.

The full text of the abstracts has been released on the SITC website,and the posters will be available on the Company's website following the conclusion of SITC 2023. Details of the poster presentations are as follows:

Title:

Givastomig,a novel Claudin18.2/4-1BB bispecific antibody,exerts bystander tumor-killing and synergistic anti-tumor activity with therapeutics in 1L/2L treatment for gastric cancer

Poster #:

792

Presenter:

Dr. Xuejun Liu,I-Mab

Date/Time:

Saturday,November 4,2023

9:00 a.m. – 8:30 p.m. Pacific Time (12:00 p.m. – 11:30 p.m. Eastern Time)

Full abstract

https://jitc.bmj.com/content/11/Suppl_1/889

Title:

ABL503 (TJ-L14B),PD-L1×4-1BB bispecific antibody,reinvigorates exhausted tumor-infiltrating CD8+ T cells and synergizes with PD-1 blockade

Abstract ID:

845

Presenter:

Dr. Jaeho Jung,ABL Bio

Date/Time:

Friday,November 3,2023

9:00 a.m. – 7:00 p.m. Pacific Time (12:00 p.m. – 10:00 p.m. Eastern Time)

Full abstract

https://jitc.bmj.com/content/11/Suppl_1/944

About Givastomig

Givastomig,also known as TJ-CD4B/ABL111,is a bispecific antibody designed to bind to Claudin 18.2 (CLDN18.2) as a tumor engager and 4-1BB as a conditional T-Cell activator. It binds to tumor cells expressing various levels of CLDN18.2,i.e.,gastric cancer and pancreatic cancer cells,and conditionally activates intra-tumoral T cells at the tumor site through the 4-1BB arm. Givastomig appears to effectively maintain a strong tumor binding property and anti-tumor activity attributable to a synergistic effect of both CLDN18.2 antibody and 4-1BB antibody while avoiding or minimizing liver toxicity and systemic immunotoxicity commonly seen with 4-1BB antibodies as a drug class. Being developed under collaboration between I-Mab and ABL Bio,a clinical-stage biotechnology company in South Korea,givastomig is currently being investigated in a Phase 1 clinical study in the U.S. and China. In March 2022,the U.S. Food and Drug Administration (FDA) granted Orphan Drug Designation for givastomig for the treatment of gastric cancer,including cancer of the gastroesophageal junction.

About TJ-L14B/ABL503

Being developed jointly with ABL Bio (Kosdaq: 298380,hereafter "ABL"),TJ-L14B/ABL503 is a differentiated PD-L1-based bispecific antibody with the PD-L1 arm as the tumor-dependent T-cell activator and the 4-1BB arm as the conditional T cell activator upon tumor engagement. Using ABL's "Grabody-T" bispecific antibody platform technology,TJ-L14B/ABL503 stimulates 4-1BB activation only in the presence of PD-L1 expressing tumor cells to minimize the risk of off-tumor toxicity. Preclinical studies have demonstrated that the bispecific antibody shows better anti-tumor activity than equimolar doses of single agents alone or in combination. A Phase 1 study is currently being conducted in the U.S. and South Korea.

AboutI-Mab

I-Mab(Nasdaq:IMAB) is a global biotechnology companyfocused on bringing highly differentiated medicines to patients around the world through the discovery,and commercialization of novel immunotherapies and biologics.I-Mab'sinnovative pipeline is driven by internal R&D's Fast-to-Proof-of-Concept,Fast-to-Market development strategies,and through global partnerships.For more information,please visithttps://www.i-mabbiopharma.comand followus onLinkedIn,Twitter,andWeChat.

I-Mab Forward Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and other federal securities laws,including statements regarding data from clinical studies of givastomig or TJ-L14B,the potential implications of clinical data for patients,and I-Mab's advancement of,and anticipated clinical development,regulatory milestones,and commercialization of givastomig or TJ-L14B. Actual results may differ materially from those indicated in the forward-looking statements as a result of various important factors,including but not limited to I-Mab's ability to demonstrate the safety and efficacy of its drug candidates; the clinical results for its drug candidates,which may not support further development or NDA/BLA approval; the content and timing of decisions made by the relevant regulatory authorities regarding regulatory approval of I-Mab's drug candidates; I-Mab's ability to achieve commercial success for its drug candidates,if approved; I-Mab's ability to obtain and maintain protection of intellectual property for its technology and drugs; I-Mab's reliance on third parties to conduct drug development,manufacturing and other services; I-Mab's limited operating history and I-Mab's ability to obtain additional funding for operations and to complete the development and commercialization of its drug candidates; and the impact of the COVID-19 pandemic on the Company's clinical development,commercial and other operations,as well as those risks more fully discussed in the "Risk Factors" section in I-Mab's most recent annual report on Form 20-F,as well as discussions of potential risks,uncertainties,and other important factors in I-Mab's subsequent filings with the US Securities and Exchange Commission. All forward-looking statements are based on information currently available to I-Mab,and I-Mab undertakes no obligation to publicly update or revise any forward-looking statements,whether as a result of new information,future events or otherwise,except as may be required by law.

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