PC7A

PC7A is a pH-responsive amphiphilic block copolymer that self-assembles into nanoparticles to act as a potent Stimulator of Interferon Genes (STING) agonist. Developed by the University of Texas Southwestern Medical Center, it represents a novel modality distinct from traditional cyclic dinucleotide (CDN) STING agonists. PC7A binds to a non-canonical site on the STING protein, inducing polyvalent condensates that lead to a sustained immune response lasting over 48 hours, significantly longer than the ~6-hour window of conventional agonists. Its pH-responsive nature ensures stability in the bloodstream while triggering activation upon entering the acidic environment of immune cells, potentially minimizing systemic toxicity. It is currently in preclinical development for the treatment of solid tumors and has shown potential in HIV-1 therapy, including effectiveness against STING variants resistant to standard CDN drugs.