ProCTLA-4

ProCTLA-4 is a **prodrug** version of an anti-CTLA-4 antibody designed to mitigate toxicity while maintaining antitumor efficacy. It is an engineered antibody that remains in an inactive form until it reaches the tumor microenvironment, where it becomes activated. The ProCTLA-4 antibody is designed with enhanced antibody-dependent cellular cytotoxicity (ADCC) functionality - the ProCTLA-4ADCC variant exhibits a five-fold increase in ADCC effect compared to standard versions[4]. This next-generation probody approach aims to reduce the systemic immune-related adverse events commonly associated with conventional CTLA-4 inhibitors while preserving therapeutic benefit. ProCTLA-4 works by blocking CTLA-4 (cytotoxic T-lymphocyte-associated protein 4), an immune checkpoint protein that acts as a brake on T-cell activation, thereby allowing the immune system to mount a stronger response against cancer cells.