Provectus announces notice of allowance of U.S. patent on rose bengal sodium

Provectus announced that the United States Patent and Trademark Office has allowed patent application 17/488,430, titled “Halogenated Xanthenes as Vaccine Adjuvants.” The allowed patent application covers the use of Provectus’s pharmaceutical-grade rose bengal sodium drug substance as an adjuvant in anticancer, antiviral, and possibly other vaccines to potentially make them work better by enhancing T-cell response. The allowed application would be Provectus’s first patent award in the field of vaccines from the USPTO. Innovate Calgary, the innovation company of the University of Calgary in Alberta, Canada, is a co-assignee. Aru Narendran, MD, PhD, Professor of Pediatrics, Oncology, Biochemistry and Molecular Biology and Physiology and Pharmacology at the University’s Cumming School of Medicine is a co-inventor. The research underlying the allowed application was led by Dr. Narendran and his lab team. Preclinical data from ongoing research on the potential use of investigational cancer immunotherapy PV-10 as a vaccine adjuvant was the subject of a poster presentation by the Narendran Lab at the Society for Immunotherapy of Cancer 2023 annual meeting. The Narendran Lab previously discovered that PV-10 activated stimulator of interferon genes, demonstrating its potential as a vaccine adjuvant in PV-10-mediated systemic anti-tumor immune responses. This work, titled “Association of Heat Shock Proteins as Chaperone for STING: A potential link in a key immune activation mechanism revealed by a novel anticancer agent PV-10” was the subject of a poster presentation at the American Association for Cancer Research (AACR) 2020 Virtual Annual Meeting II. In its SITC 2023 work, the Narendran Lab showed that PV-10 treatment induced STING activation, upregulated cytokines and chemokines, and increased IFN-gamma secretion by CD8+ T-cells. Dr. Narendran and his colleagues demonstrated PV-10’s ability to function as an effective adjuvant to enhance T-cell responses and concluded that PV-10’s unique modulation of the STING pathway was a potential mechanism of this activity. This work also portends the potential benefit of PV-10 in combination with targeted immunotherapies and antibody-drug conjugates for cancer treatment.