Anti-PSMA/CD3 Protease-activated T-cell Engager AMX-500

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

**Definition:** A protease-activated, dual-masked, prodrug T-cell engager (TCE) composed of a prostate-specific membrane antigen (PSMA)-binding domain and a CD3-binding domain conjugated, via a tumor protease-cleavable linker, to two unstructured polypeptides (XTEN), which sterically hinder and and prevent target engagement, with potential immunomodulating and antineoplastic activities. Upon intravenous administration of anti-PSMA/CD3 protease-activated TCE AMX-500, the tumor protease-cleavable linker is proteolytically cleaved in the tumor microenvironment (TME) by dysregulated proteases which separate the TCE from the peptide mask and activates AMX-500. This allows the CD3-binding domain to target and bind to T-cells and the PSMA-binding domain to target and bind to PSMA expressed on tumor cells, thereby killing the PSMA-expressing tumor cells. PSMA, a tumor-associated antigen (TAA) and type II transmembrane protein, is expressed on the membrane of prostatic epithelial cells and overexpressed on prostate tumor cells as well as a variety of other solid tumors. By allowing specific activation of AMX-500 in the TME, systemic toxicity is reduced and efficacy is increased.

**Synonyms:** - AMX 500 - AMX-500 - AMX500 - Anti-PSMA/Anti-CD3 Protease-activated TCE AMX-500 - Anti-PSMA/CD3 Protease-activated TCE AMX-500 - Masked PSMA TCE AMX-500 - PSMA-targeted Tumor-activated T Cell Engager AMX-500 - SAR 446329 - SAR-446329 - SAR446329 - VIR 5500 - VIR-5500 - VIR5500