Definition

A lipid nanoparticle (LNP) encapsulating a messenger RNA (mRNA) encoding for a monoclonal antibody directed against the tumor-associated antigen (TAA) Claudin18.2 (CLDN18.2; A2 isoform of claudin-18), with potential immunostimulating and antineoplastic activities. Upon administration, mRNA-encoded anti-claudin18.2 monoclonal antibody BNT141 binds to the plasma membrane of cells and releases the mRNA into the cells. The mRNA is then translated by ribosomes to produce the anti-CLDN18.2 monoclonal antibody. The antibody specifically targets, binds to and inhibits CLDN18.2 expressed on tumor cells. This may kill CLDN18.2-expressing tumor cells. CLDN18.2, a tight junction protein and stomach-specific isoform of claudin-18, is overexpressed on a variety of tumor cells, but its expression in healthy tissues is strictly confined to short-lived differentiated epithelial cells of the gastric mucosa.