DAY301

DAY301 is a potentially first-in-class antibody-drug conjugate (ADC) targeting protein tyrosine kinase 7 (PTK7), a catalytically inactive transmembrane protein highly expressed on the surface of multiple adult and pediatric cancers. These include platinum-resistant ovarian cancer, triple negative breast cancer, non-small cell lung cancer, neuroblastoma, osteosarcoma, esophageal cancer, endometrial cancer, rhabdomyosarcoma and others. PTK7 has limited expression in normal tissues or organs. The mechanism of action involves selective binding to PTK7-expressing tumor cells and delivery of a cytotoxic payload via the ADC construct. Preclinical studies have shown antitumor activity across a wide range of solid tumors. The drug is being developed to maximize therapeutic index and overcome limitations seen with previous-generation PTK7-targeted ADCs. As of April 2024 it received IND clearance from the FDA for clinical trials.