Phio Pharmaceuticals Corp., a clinical stage biopharmaceutical company, engages in the development of immuno-oncology therapeutics in the United States. It develops PH-762, an INTASYL compound designed to reduce the expression of PD-1 in multi-center Phase 1b dose-escalating clinical trials; PH-894, an INTASYL compound that is designed to specifically silence BRD4, a protein that controls gene expression in both T cells and tumor cells in preclinical studies. The company was formerly known as RXi Pharmaceuticals Corporation and changed its name to Phio Pharmaceuticals Corp. in November 2018. Phio Pharmaceuticals Corp. was founded in 2003 and is based in King Of Prussia, Pennsylvania.