PH-894 protection for chemical structure, genetic sequencing and broad application for proliferative and infectious diseases in U.S.

King of Prussia, Pennsylvania--(Newsfile Corp. - August 11, 2026) - Phio Pharmaceuticals Corp. (NASDAQ:PHIO), a clinical-stage biotechnology company developing immuno-oncology therapeutics based on its proprietary INTASYL® gene-silencing technology, today announced the receipt of a U.S. Notice of Allowance for a patent covering PH-894, further strengthening the Company's intellectual property portfolio.

The patent allowance represents a critical milestone in protecting Phio's strategic interest in the Company's INTASYL® platform. PH-894, designed to selectively silence BRD4, is a key regulator of gene expression associated with proliferative and infectious disease.