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

<p>PH-894 protection for chemical structure, genetic sequencing and broad application for proliferative and infectious diseases in U.S.</p><p>King of Prussia, Pennsylvania--(Newsfile Corp. - August 11, 2026) - Phio Pharmaceuticals Corp. (NASDAQ:<a class="ticker" href="https://www.benzinga.com/quote/PHIO">PHIO</a>), a clinical-stage biotechnology company developing immuno-oncology therapeutics based on its proprietary INTASYL&#174; 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.</p><p>The patent allowance represents a critical milestone in protecting Phio's strategic interest in the Company's INTASYL&#174; platform. PH-894, designed to selectively silence BRD4, is a key regulator of gene expression associated with proliferative and infectious disease.</p><p>"Robust intellectual property protection is a continuous focus in our development strategy to advance novel immuno-oncology therapies and maximize the long-term value of the INTASYL platform," said Robert Bitterman, President and Chief Executive Officer of Phio Pharmaceuticals. "This patent advancement solidifies our commitment to advance PH-894 in the U.S. and pursue strategic collaborations internationally."</p><p>Phio has built a comprehensive patent estate supporting its INTASYL&#174; technology and therapeutic pipeline. The Company's portfolio currently includes 54 issued patents covering INTASYL chemistry, specific gene targets, immuno-oncology compounds, and therapeutic applications across major global markets.</p><p>The newly allowed patent further reinforces Phio's commitment to protecting its proprietary innovations and advancing next-generation cancer therapies based on targeted gene silencing.</p><p><b>About Phio Pharmaceuticals Corporation</b></p><p>Phio Pharmaceuticals Corp. (NASDAQ:<a class="ticker" href="https://www.benzinga.com/quote/PHIO">PHIO</a>) is a clinical-stage biopharmaceutical company advancing its proprietary INTASYL<sup>&#174;</sup> siRNA gene silencing technology to eliminate cancer. Phio's INTASYL compounds are designed to enhance the body's immune cells to more effectively kill cancer cells. Phio's lead clinical development program is an INTASYL compound, PH-762, that silences the PD-1 gene implicated in various forms of skin cancer. The Phase 1b trial (NCT# 06014086) evaluated PH-762 for the treatment of cutaneous squamous cell carcinoma, melanoma and Merkel cell carcinoma. PH-762 is a potential non-surgical treatment for skin cancers.</p><p>For additional information, visit the Company's website, <a href="https://api.newsfilecorp.com/redirect/xEopMCVn2R" target="_blank">www.phiopharma.com</a>.  </p><p><b>Forward-Looking Statements</b></p><p><i>This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements can be identified by words such as "intends," "believes," "anticipates," "indicates," "plans," "expects," "suggests," "may," "would," "should," "potential," "designed to," "will," "ongoing," "estimate," "forecast," "target," "predict," "could" and similar references, although not all forward-looking statements contain these words. These statements, which include statements, among other things, regarding the anticipated benefits of our INTASYL&#8482; RNAi platform, our ability and plans to continue developing, advancing and protecting the breakthrough technologies and related intellectual property underlying our INTASYL&#8482; compounds, the results from our ongoing clinical trials, our belief that the receipt of a U.S. Notice of Allowance for a patent covering PH-894 solidifies our commitment to advance PH-894 in the U.S. and pursue strategic collaborations internationally, details regarding our planned non-clinical toxicology study, and our ability to support ongoing clinical development, operational requirements and strategic initiatives with the capital we currently have on hand, are based only on our current beliefs, expectations and assumptions and are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict and many of which are outside of our control. Our actual results may differ materially from those indicated in the forward-looking statements as a result of a number of important factors, including, but not limited to, the impact of future FDA interactions on the development of our product candidates; the impact to our business and operations by inflationary pressures; recession fears; the development of our product candidates, results from our nonclinical, preclinical and clinical activities, our ability to execute on business strategies, our ability to develop our product candidates with collaboration partners, and the success of any such collaborations, the timeline and duration for advancing our product candidates into clinical development, the timing or likelihood of regulatory filings and approvals, the success of our efforts to commercialize our product candidates if approved, our ability to manufacture and supply our product candidates for clinical activities, and for commercial use if approved, the scope of protection we are able to establish and maintain for intellectual property rights covering our technology platform, our ability to obtain future financing, market and other conditions and those risks identified in our most recent Annual Report on Form 10-K and subsequent Quarterly Reports on Form 10-Q under the caption "Risk Factors" and in other filings the Company periodically makes with the U.S. Securities and Exchange Commission. Readers are urged to review these risk factors and to not act in reliance on any forward-looking statements, as actual results may differ from those contemplated by our forward-looking statements. Phio does not undertake to update forward-looking statements to reflect a change in its views, events or circumstances that occur after the date of this release, except as required by law.</i></p><div id="contactInfo"><p><b>Contact:<br />Phio Pharmaceuticals Corp.<br /></b>Jennifer Phillips: <a href="mailto:jphillips@phiopharma.com" target="_blank">jphillips@phiopharma.com<br /></a>Corporate Affairs </p></div><p id="corporateNewsLogoContainer"><img src="https://images.newsfilecorp.com/files/10407/309064_b4e5d5e9f412d8cc_logo.jpg" id="corporateNewsLogo" alt="Corporate Logo" /></p><p id="corporateLinkBack">To view the source version of this press release, please visit <a href="https://api.newsfilecorp.com/redirect/7n4kEfPyBG">https://www.newsfilecorp.com/release/309064</a></p><p><img src="https://api.newsfilecorp.com/newsinfo/309064/197" alt="" /></p>

PHIO

Phio Pharmaceuticals Secures U.S. Notice of Allowance for INTASYL Composition Selectively Targeting BRD4 Protein with Compound PH-894

PHIO patent allowance strengthens INTASYL moat and collaboration potential

<section class="insight" data-version="1">
  <section data-block="information">
    <h3>Information</h3>
    <p>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</p>
  </section>

  <section data-block="ai-summary-paragraph">
    <h3>AI Summary</h3>
    <p>Phio Pharmaceuticals announced a U.S. Notice of Allowance for PH-894, a BRD4-targeting INTASYL agent, bolstering its IP moat and potential licensing opportunities. The milestone complements a 54-issued patent portfolio and supports PHIO&#039;s broader immuno-oncology strategy, including PH-762 (PD-1 silencing) in a Phase 1b trial for skin cancers, which could catalyze partnerships and value realization.</p>
  </section>

  <section data-block="ai-summary-bullets">
    <h3>Key Points</h3>
    <ul><li>PHIO gains U.S. patent allowance for PH-894. Strengthens INTASYL IP and collaboration leverage.</li><li>PH-894 silences BRD4, a key regulator of gene expression. Supports broader disease applications.</li><li>INTASYL portfolio has 54 issued patents worldwide. Expands moat and roadmap.</li><li>CEO emphasizes PH-894 in the U.S.; pursuing international collaborations.</li><li>PHIO&#039;s lead PH-762 targets PD-1 in skin cancers; Phase 1b trial. NCT06014086.</li></ul>
  </section>

  <section data-block="companies-mentioned">
    <h3>Companies Mentioned</h3>
    <ul><li><strong>Phio Pharmaceuticals Corp. (PHIO)</strong>: Patent allowance strengthens INTASYL IP and potential collaboration opportunities; supports valuation.</li></ul>
  </section>

  <section data-block="category">
    <h3>Legal</h3>
    <p>This is a Legal/Corporate Developments milestone focused on intellectual property; it reinforces the strategic moat around Phio&#039;s INTASYL platform and may enable partnerships, affecting long-term value assumptions.</p>
  </section>

  <section data-block="market-moving">
    <h3>Market-Moving</h3>
    <ul><li>U.S. Notice of Allowance for PH-894 expands IP moat.</li><li>INTASYL portfolio now includes 54 issued patents.</li><li>Potential for strategic collaborations internationally highlighted by management.</li><li>PHIO&#039;s PH-762 PD-1 program in Phase 1b (NCT06014086) remains a near-term catalyst.</li></ul>
  </section>

  <section data-block="key-facts">
    <h3>Key Facts</h3>
    <ul><li>Notice of Allowance for PH-894 received in August 2026.</li><li>PH-894 is designed to selectively silence BRD4, a regulator of gene expression.</li><li>INTASYL-related patents total 54 issued worldwide.</li><li>PHIO&#039;s lead program PH-762 targets PD-1; Phase 1b trial (NCT06014086) ongoing.</li></ul>
  </section>

  <section data-block="trading-thesis">
    <h3>Trading Thesis</h3>
    <p>Bullish over the next 1–3 quarters as IP protection strengthens and collaboration potential may unlock near-term value.</p>
  </section>
</section>


<p>PH-894 protection for chemical structure, genetic sequencing and broad application for proliferative and infectious diseases in U.S.</p><p>King of Prussia, Pennsylvania--(Newsfile Corp. - August 11, 2026) - Phio Pharmaceuticals Corp. (NASDAQ:<a class="ticker" href="https://www.benzinga.com/quote/PHIO">PHIO</a>), a clinical-stage biotechnology company developing immuno-oncology therapeutics based on its proprietary INTASYL&#174; 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.</p><p>The patent allowance represents a critical milestone in protecting Phio's strategic interest in the Company's INTASYL&#174; platform. PH-894, designed to selectively silence BRD4, is a key regulator of gene expression associated with proliferative and infectious disease.</p><p>"Robust intellectual property protection is a continuous focus in our development strategy to advance novel immuno-oncology therapies and maximize the long-term value of the INTASYL platform," said Robert Bitterman, President and Chief Executive Officer of Phio Pharmaceuticals. "This patent advancement solidifies our commitment to advance PH-894 in the U.S. and pursue strategic collaborations internationally."</p><p>Phio has built a comprehensive patent estate supporting its INTASYL&#174; technology and therapeutic pipeline. The Company's portfolio currently includes 54 issued patents covering INTASYL chemistry, specific gene targets, immuno-oncology compounds, and therapeutic applications across major global markets.</p><p>The newly allowed patent further reinforces Phio's commitment to protecting its proprietary innovations and advancing next-generation cancer therapies based on targeted gene silencing.</p><p><b>About Phio Pharmaceuticals Corporation</b></p><p>Phio Pharmaceuticals Corp. (NASDAQ:<a class="ticker" href="https://www.benzinga.com/quote/PHIO">PHIO</a>) is a clinical-stage biopharmaceutical company advancing its proprietary INTASYL<sup>&#174;</sup> siRNA gene silencing technology to eliminate cancer. Phio's INTASYL compounds are designed to enhance the body's immune cells to more effectively kill cancer cells. Phio's lead clinical development program is an INTASYL compound, PH-762, that silences the PD-1 gene implicated in various forms of skin cancer. The Phase 1b trial (NCT# 06014086) evaluated PH-762 for the treatment of cutaneous squamous cell carcinoma, melanoma and Merkel cell carcinoma. PH-762 is a potential non-surgical treatment for skin cancers.</p><p>For additional information, visit the Company's website, <a href="https://api.newsfilecorp.com/redirect/xEopMCVn2R" target="_blank">www.phiopharma.com</a>.  </p><p><b>Forward-Looking Statements</b></p><p><i>This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements can be identified by words such as "intends," "believes," "anticipates," "indicates," "plans," "expects," "suggests," "may," "would," "should," "potential," "designed to," "will," "ongoing," "estimate," "forecast," "target," "predict," "could" and similar references, although not all forward-looking statements contain these words. These statements, which include statements, among other things, regarding the anticipated benefits of our INTASYL&#8482; RNAi platform, our ability and plans to continue developing, advancing and protecting the breakthrough technologies and related intellectual property underlying our INTASYL&#8482; compounds, the results from our ongoing clinical trials, our belief that the receipt of a U.S. Notice of Allowance for a patent covering PH-894 solidifies our commitment to advance PH-894 in the U.S. and pursue strategic collaborations internationally, details regarding our planned non-clinical toxicology study, and our ability to support ongoing clinical development, operational requirements and strategic initiatives with the capital we currently have on hand, are based only on our current beliefs, expectations and assumptions and are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict and many of which are outside of our control. Our actual results may differ materially from those indicated in the forward-looking statements as a result of a number of important factors, including, but not limited to, the impact of future FDA interactions on the development of our product candidates; the impact to our business and operations by inflationary pressures; recession fears; the development of our product candidates, results from our nonclinical, preclinical and clinical activities, our ability to execute on business strategies, our ability to develop our product candidates with collaboration partners, and the success of any such collaborations, the timeline and duration for advancing our product candidates into clinical development, the timing or likelihood of regulatory filings and approvals, the success of our efforts to commercialize our product candidates if approved, our ability to manufacture and supply our product candidates for clinical activities, and for commercial use if approved, the scope of protection we are able to establish and maintain for intellectual property rights covering our technology platform, our ability to obtain future financing, market and other conditions and those risks identified in our most recent Annual Report on Form 10-K and subsequent Quarterly Reports on Form 10-Q under the caption "Risk Factors" and in other filings the Company periodically makes with the U.S. Securities and Exchange Commission. Readers are urged to review these risk factors and to not act in reliance on any forward-looking statements, as actual results may differ from those contemplated by our forward-looking statements. Phio does not undertake to update forward-looking statements to reflect a change in its views, events or circumstances that occur after the date of this release, except as required by law.</i></p><div id="contactInfo"><p><b>Contact:<br />Phio Pharmaceuticals Corp.<br /></b>Jennifer Phillips: <a href="mailto:jphillips@phiopharma.com" target="_blank">jphillips@phiopharma.com<br /></a>Corporate Affairs </p></div><p id="corporateNewsLogoContainer"><img src="https://images.newsfilecorp.com/files/10407/309064_b4e5d5e9f412d8cc_logo.jpg" id="corporateNewsLogo" alt="Corporate Logo" /></p><p id="corporateLinkBack">To view the source version of this press release, please visit <a href="https://api.newsfilecorp.com/redirect/7n4kEfPyBG">https://www.newsfilecorp.com/release/309064</a></p><p><img src="https://api.newsfilecorp.com/newsinfo/309064/197" alt="" /></p>

Phio Pharmaceuticals announced a U.S. Notice of Allowance for PH-894, a BRD4-targeting INTASYL agent, bolstering its IP moat and potential licensing opportunities. The milestone complements a 54-issued patent portfolio and supports PHIO's broader immuno-oncology strategy, including PH-762 (PD-1 silencing) in a Phase 1b trial for skin cancers, which could catalyze partnerships and value realization.

News insight

Phio Pharmaceuticals Secures U.S. Notice of Allowance for INTASYL Composition Selectively Targeting BRD4 Protein with Compound PH-894

AI summary

Sentiment rationale

Key facts

Legal