Phio Pharmaceuticals Corp is a clinical-stage biopharmaceutical company specializing in the development of immuno-oncology therapeutics using its proprietary INTASYL self-delivering siRNA gene silencing technology. The company focuses on leveraging its INTASYL platform to develop treatments that enhance the body's immune response by silencing genes that suppress immune function, specifically targeting cancers such as cutaneous squamous cell carcinoma (cSCC), melanoma, and Merkel cell carcinoma. Phio's main product candidate, PH-762, is an INTASYL compound designed to silence the PD-1 gene, offering a potential non-surgical treatment option for these skin cancers. The company conducts multi-center Phase 1b clinical trials for PH-762, evaluating its safety, tolerability, and efficacy through intratumoral injections.
In recent developments, Phio Pharmaceuticals completed enrollment in its Phase 1b clinical trial of PH-762, reporting positive interim safety and efficacy results, including significant tumor clearance in several patients, with one case showing 100% tumor clearance at the maximum dose cohort. The company also secured approximately $12.1 million through warrant inducements and estimates having cash reserves sufficient to sustain operations into the first half of 2027. In 2024, Phio terminated its Clinical Co-Development Agreement with AgonOx, Inc., redirecting efforts and resources towards the self-directed development of PH-762. Furthermore, the company announced an exploratory collaboration with a luxury skin care company to explore applications of its INTASYL compound.
Phio Pharmaceuticals, founded in 2001 and headquartered in King of Prussia, Pennsylvania, markets its technologies primarily within the United States but operates clinical trials that involve multiple centers. Its pipeline emphasizes immuno-oncology, particularly therapies that silence immune checkpoint targets such as PD-1 and TIGIT using siRNA technology. The company positions itself in the biotechnology sector within the immunotherapy and RNA interference market segments, aiming to provide innovative gene-silencing therapeutics with broad potential applications in oncology and other diseases. Recent strategic initiatives include focused clinical development progression, financing rounds to support ongoing trials, and expanding the utilization of its INTASYL platform beyond oncology.
Phio Pharmaceuticals continues to advance its INTASYL technology with a commitment to developing non-surgical treatment alternatives for cancer patients, supported by a robust clinical trial program and strategic financing efforts to accelerate its drug development pipeline. The company’s evolving portfolio and strategic partnerships underpin its growth and innovation within the competitive immuno-oncology biopharmaceutical landscape.