Pamlectabart Tismanitin

**Semantic type:** Pharmacologic Substance

**Definition:** An antibody-drug conjugate (ADC) consisting of pamlectabart, a humanized immunoglobulin G1-kappa monoclonal antibody against the tumor-associated antigen (TAA) B-cell maturation antigen (BCMA, TNFRSF17) conjugated with tismanitin, which consists of a cleavable linker and the cytotoxic, RNA polymerase II inhibitor alpha-amanitin, with potential antineoplastic activity. Upon administration of pamlectabart tismanitin, the pamlectabart moiety targets and binds to the cell surface antigen BCMA expressed on certain cancer cells. Upon antibody/antigen binding, internalization and cleavage, the cytotoxic alpha-amanitin is released. Alpha-amanitin binds to and inhibits RNA polymerase II, prevents RNA synthesis, induces apoptosis, and inhibits the proliferation of BCMA-overexpressing tumor cells. BCMA, a receptor for a proliferation-inducing ligand (APRIL; tumor necrosis factor ligand superfamily member 13; TNFSF13), and B-cell activating factor (BAFF), is a member of the tumor necrosis factor (TNF) receptor superfamily and plays a key role in plasma survival; it is found on the surfaces of plasma cells and is overexpressed on malignant plasma cells.

**Synonyms:** - ADC HDP-101 - Anti-BCMA Antibody-drug Conjugate HDP-101 - Anti-BCMA/Alpha-amanitin ADC HDP-101 - Anti-BCMA/Alpha-amanitin Antibody-drug Conjugate HDP-101 - HDP 101 - HDP-101 - HDP101 - PAMLECTABART TISMANITIN