HRI Associates

HRI Associates was a pioneering biotechnology company founded in 1979 by Stephen T. Isaacs, John Hearst, and Henry Rapoport to commercialize psoralen-based photochemical technology. The company specialized in the synthesis of novel psoralen derivatives designed to inactivate pathogens, including viruses and bacteria, in blood components for transfusion. HRI Associates served as a critical research and development hub and a supplier of specialized compounds to the early biotech industry before evolving into Cerus Corporation in 1991. Its foundational work laid the basis for the INTERCEPT Blood System, which is now used globally for blood safety. The company's technology utilizes small molecule psoralens that, when activated by ultraviolet light, permanently cross-link the DNA and RNA of pathogens to prevent replication. This approach revolutionized the field of transfusion medicine by providing a proactive method to ensure the safety of platelets, plasma, and red blood cells.