XTX601

XTX601 is an investigational, tumor-activated (masked) T-cell engager (TCE) designed to target Claudin 18.2 (CLDN18.2). Developed by Xilio Therapeutics using its proprietary masking technology, XTX601 is engineered to remain inactive in systemic circulation and undergo selective activation within the tumor microenvironment (TME) via protease cleavage. This mechanism is intended to enhance the therapeutic index by localizing T-cell mediated cytotoxicity to the tumor while minimizing off-tumor, on-target toxicities in healthy tissues. In March 2024, AbbVie entered into a strategic discovery alliance with Xilio, securing an exclusive option to license XTX601 and other masked TCE programs targeting PSMA and STEAP1.

Other names

CLDN18.2 masked T cell engagerCLDN-18.2 masked T cell engagerCLDN 18.2 masked T cell engagerXilio CLDN18.2 ATACR