Xilio Therapeutics Announces Multiple Masked T Cell Engager Programs

Core Viewpoint - Xilio Therapeutics has announced a collaboration with AbbVie to develop novel tumor-activated immunotherapies, including masked T cell engagers, with an upfront payment of $52 million, extending its cash runway into Q1 2026 [1][11]. Collaboration and Financial Details - The collaboration includes a cash payment of $42 million and an equity investment of $10 million from AbbVie [11]. - Xilio is eligible for up to approximately $2.1 billion in additional contingent payments, which consist of option-related fees and development, regulatory, and sales-based milestones [11]. - The company anticipates that its existing cash, along with the upfront payment from AbbVie, will be sufficient to fund operations into the first quarter of 2026 [7]. Product Development and Pipeline - Xilio is advancing three wholly-owned preclinical programs targeting prostate-specific membrane antigen (PSMA), claudin 18.2 (CLDN18.2), and six-transmembrane epithelial antigen of prostate 1 (STEAP1) [5]. - The PSMA program is expected to nominate a development candidate in Q3 2025 and submit an investigational new drug application (IND) in Q1 2027 [5]. - The CLDN18.2 program aims to nominate a candidate in Q4 2025 and submit an IND in Q2 2027 [5]. - The STEAP1 program plans to nominate a candidate in the first half of 2026 and submit an IND in the second half of 2027 [5]. Technology and Innovation - Xilio's tumor-activation platform is designed to improve tolerability and enhance T cell activation through tumor-selective activation [2][4]. - The company is developing bispecific and tri-specific molecules using its advanced formats, ATACR and SEECR, to enhance potency and T cell activation [4]. Investor Engagement - Xilio will host an investor conference call and webcast to discuss these developments [8].