About T Cell Engagers

T cell engagers are designed to redirect immune effector cells against cancer cells by simultaneously binding to a specific tumor-associated antigen expressed on the cancer cells and the T cell receptor complex on T cells. To date, T cell engagers have demonstrated significant promise for cancer immunotherapy in a variety of advanced solid tumors, but the potential has been limited by toxicity.

Xilio’s Masked T Cell Engagers (TCEs)

We are currently leveraging our proprietary, clinically-validated masking technology and modular TCE architectures to advance two wholly-owned TCE programs, as well as an additional masked TCE program in collaboration with AbbVie.

Our masked TCEs are designed with a masked CD3 targeting domain and one or more tumor-associated antigen (TAA) binding domains as part of the core molecule design. In addition, our modular architecture enables the incorporation of a co-stimulatory domain designed to further enhance potency and durability of T cell response, as well as the potential to mask the TAA binding domain(s) and/or mask the co-stimulatory signaling domain. Upon tumor-selective activation, our TCE molecules are designed to release a potent, short half-life TCE in the tumor microenvironment.

PSMA+STEAP1 Program

We are advancing a potential first-in-class masked TCE program targeting PSMA and STEAP1 with built-in co-stimulatory signaling. PSMA and STEAP1 are TAAs expressed in prostate cancer.

We plan to submit an IND for our PSMA+STEAP1 program in the second half of 2027.

CLDN18.2 Program

We are advancing a potential first-in-class masked TCE program targeting CLDN18.2. CLDN18.2 is a TAA expressed in gastrointestinal cancers (gastric, pancreatic and esophageal).

We plan to submit an IND for our CLDN18.2 program in the second half of 2027.