A PSMA-Targeted, CD2-Costimulating T-Cell Engager with Strong Preclinical Efficacy & a Favorable GLP Toxicology Profile
- PSMA is highly expressed in prostate cancer, and single-cell RNA sequencing of metastatic tumor-infiltrating lymphocytes identifies CD2 as a broadly expressed co-stimulatory receptor, particularly on CD8+ T cells
- QL535, a trispecific PSMA × CD3 × CD2 molecule (2+1+1 TECOS format), delivers CD3 activation and CD2 co-stimulation to enhance cytotoxicity while limiting cytokine release compared with benchmark T-cell engagers
- QL535 demonstrates superior PSMA-dependent killing in vitro, sustained activity under repeated stimulation, dose-responsive tumor regression in PSMA+ PDX models, and a favorable GLP toxicology profile in non-human primates, supporting its clinical development for PSMA-positive prostate cancer