• INTASYL compounds also improve the functionality and outcomes of adoptive cell therapies such as NK, TIL and CAR-T

Marlborough, Massachusetts--(Newsfile Corp. - October 7, 2024) - Phio Pharmaceuticals Corp. (Nasdaq: PHIO), a clinical stage biotechnology company whose proprietary INTASYL^® siRNA gene silencing technology is designed to make immune cells more effective in killing tumor cells, today announced that it is presenting data about its proprietary INTASYL platform and INTASYL compounds.

INTASYL compounds offer precise targeting by silencing mRNA both intracellularly and extracellularly, significantly enhancing immune responses against cancer. They are effective as intratumoral injections and as excipients during immune cell expansion for adoptive cell therapy. INTASYL's efficient delivery system requires no special formulations to streamline siRNA delivery to target cells.

INTASYL compound PH-762 silences PD-1, improving therapeutic efficacy in vivo. The PH-894 compound precisely silences BRD4 to enhance tumor cell immunogenicity and induce apoptosis. Silencing TIGIT in NK cells, using compound PH-804, enhances their activation, cytokine release, and target cell killing. The PH-905 compound silences CBLB, increasing NK cell cytotoxicity and proliferation.

The data is being presented on October 8^th at the 20th Annual Oligonucleotide Therapeutics Society (OTS) Meeting in Montreal.

About Phio Pharmaceuticals Corp.

Phio Pharmaceuticals Corp. (Nasdaq: PHIO) is a clinical-stage biotechnology company focused on silencing specific genes using its proprietary INTASYL siRNA technology. In non-systemic applications, INTASYL can target and silence virtually any gene with high specificity across a wide range of tissue types. INTASYL is primarily designed to enhance the ability of immune cells to kill tumor cells and can play a key role in improving adoptive cell therapy. Notably, INTASYL is the only self-delivering RNAi technology, in that does not require specialized formulations or drug delivery systems.

For additional information, visit the Company's website, www.phiopharma.com.

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