PRX302 is highly targeted to prostate tissue and the therapy is designed to be non-systemic. It is delivered directly to the encapsulated prostate via localized injection. Further, PRX302 has been engineered to be selectively activated by enzymatically active Prostate Specific Antigen (PSA) which is present only in prostate tissue. Once activated, PRX302 forms disruptive pores in the membranes of prostate cells resulting in selective cell death, thus creating a highly targeted, localized approach to killing prostate cells.
PRX302 is a recombinant form of the native proaerolysin protein. Native proaerolysin binds to glycophosphatidylinositol (GPI)-anchored proteins found on the surface of most mammalian cells. Proaerolysin contains a carboxy-terminal inhibitory domain that is cleaved by ubiquitous membrane-bound proteases, such as the furins, producing aerolysin, which rapidly oligomerizes and inserts into the plasma membrane to form highly stable pores that cause rapid cell death. PRX302 has been genetically modified by replacing the furin-cleavage sequence with a PSA-selective sequence.