D2AP11-TCE

D2AP11-TCE is a bispecific T cell engager (TCE) that targets the follicle-stimulating hormone receptor (FSHR) on ovarian cancer cells and CD3 on T cells. Engineered from the monoclonal antibody D2AP11, which specifically binds to the external domain of FSHR, D2AP11-TCE is designed to link T cells directly to FSHR-expressing tumor cells, triggering potent, antigen-specific T cell-mediated cytotoxicity. Preclinical results show that D2AP11-TCE exhibits high specificity and killing efficacy against a wide genetic range of ovarian cancer cell lines, including those with BRCA1/2 mutations and resistance to multiple therapies, with EC50 values in the low nanogram per milliliter range. Notably, the bispecific format of D2AP11-TCE provides much greater cytolytic potency than the parental D2AP11 antibody. The drug also induces robust antitumor cytokine and cytotoxic molecule release (IFN-γ, sFas, granzyme A/B, perforin) and reduces tumor burden in ovarian cancer mouse models. Mechanistically, D2AP11-TCE mediates T cell redirection and activation via CD3 engagement while providing highly selective targeting of ovarian cancer cells through FSHR, making it a promising immunotherapy candidate for recurrent, resistant, or high-risk ovarian cancer.