Anti-CD3/Anti-Claudin18.2 Bispecific Antibody IBI389

**Semantic type:** Amino Acid, Peptide, or Protein|Immunologic Factor|Pharmacologic Substance

**Definition:** A bispecific antibody directed against the tumor-associated antigen (TAA) Claudin18.2 (CLDN18.2; A2 isoform of claudin-18) and the human T-cell surface antigen CD3, with potential immunostimulatory and antineoplastic activities. Upon administration, anti-CD3/anti-CLDN18.2 bispecific antibody IBI389 simultaneously binds to both CD3-expressing T-cells and CLDN18.2-expressing cancer cells, thereby crosslinking CLDN18.2-expressing tumor cells and cytotoxic T-lymphocytes (CTLs). This results in the activation and proliferation of T-cells and causes CTL-mediated cell lysis of CLDN18.2-expressing tumor cells. CLDN18.2, a tight junction protein and stomach-specific isoform of claudin-18, is expressed on a variety of tumor cells. Its expression in healthy tissues is strictly confined to short-lived differentiated epithelial cells of the gastric mucosa.

**Synonyms:** - Anti-CD3/Anti-CLDN18.2 Bispecific Antibody IBI389 - Anti-CLDN18.2/Anti-CD3 Bispecific Antibody IBI389 - Anti-Claudin18.2/CD3 Bispecific Antibody IBI389 - CLDN18.2 x CD3 Bispecific Antibody IBI389 - IBI 389 - IBI-389 - IBI389