Anti-LYPD1/CD3 T cell dependent bispecific antibody for the treatment of ovarian cancer.

Ovarian cancer is a diverse class of tumors with very few effective treatment options and suboptimal response rates in early clinical studies using immunotherapies. Here we describe LY6/PLAUR domain containing 1 (LYPD1) as a novel target for therapeutic antibodies for the treatment of ovarian cancer. LYPD1 is broadly expressed in both primary and metastatic ovarian cancer with ~70% prevalence in the serous cancer subset. Bispecific antibodies targeting CD3 on T cells and a tumor antigen on cancer cells have demonstrated significant clinical activity in hematological cancers. We have developed an anti-LYPD1/CD3 T cell dependent bispecific antibody (TDB) to redirect T cell responses to LYPD1 expressing ovarian cancer. Here we characterize the non-clinical pharmacology of anti-LYPD1/CD3 TDB and show induction of a robust polyclonal T cell activation and target dependent killing of LYPD1 expressing ovarian cancer cells resulting in efficient in vivo anti-tumor responses in PBMC reconstituted immune deficient mice and human CD3 transgenic mouse models. Anti-LYPD1/CD3 TDB is generally well tolerated at high dose levels in mice, a pharmacologically relevant species, and showed no evidence of toxicity or damage to LYPD1 expressing tissues.