# EDGAR Filing Document

**Accession Number:** 0001533040
**File Stem:** 0001437749-25-032662
**Filing Date:** 2025-11
**Character Count:** 12471
**Document Hash:** 27d49cb1517f14aad6a8d5e9e61bbbc1
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001437749-25-032662.hdr.sgml**: 20251103

**ACCESSION NUMBER**: 0001437749-25-032662

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 15

**CONFORMED PERIOD OF REPORT**: 20251103

**ITEM INFORMATION**: Other Events

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20251103

**DATE AS OF CHANGE**: 20251103

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Phio Pharmaceuticals Corp.
- **CENTRAL INDEX KEY:** 0001533040
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 453215903
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-36304
- **FILM NUMBER:** 251442170

**BUSINESS ADDRESS:**
- **STREET 1:** 411 SWEDELAND ROAD
- **STREET 2:** SUITE 23-1080
- **CITY:** KING OF PRUSSIA
- **STATE:** PA
- **ZIP:** 19406
- **BUSINESS PHONE:** (508) 767-3861

**MAIL ADDRESS:**
- **STREET 1:** 411 SWEDELAND ROAD
- **STREET 2:** SUITE 23-1080
- **CITY:** KING OF PRUSSIA
- **STATE:** PA
- **ZIP:** 19406

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** RXi Pharmaceuticals Corp
- **DATE OF NAME CHANGE:** 20111019

?xml version='1.0' encoding='ASCII'? phio20251023_8k.htm

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**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

**FORM 8-K**

**CURRENT REPORT**

**Pursuant to Section 13 or 15(d)**

**of the Securities Exchange Act of 1934**

**Date of report (Date of earliest event reported): November 3, 2025**

**PHIO PHARMACEUTICALS CORP.**

**(Exact name of registrant as specified in its charter)**

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| | | |
|:---|:---|:---|
| **Delaware** | **001-36304** | **45-3215903** |
| (State or other jurisdiction of incorporation) | (Commission File Number) | (I.R.S. Employer Identification No.) |

---

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| | |
|:---|:---|
| **411 Swedeland Road, Suite 23-1080** |  |
| **King of Prussia, PA** | **19406** |
| (Address of principal executive offices) | (Zip Code) |

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Registrant's telephone number, including area code: **(610) 947-0251**

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

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| | | |
|:---|:---|:---|
| Title of each class: | Trading Symbol(s): | Name of each exchange on which registered: |
| **Common Stock, par value $0.0001 per share** | **PHIO** | **The Nasdaq Capital Market** |

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Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

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**Item 8.01. Other Events.**

On November 3, 2025, Phio Pharmaceuticals Corp. ("Phio") issued a press release announcing (i) 100% tumor clearance (Complete Response) in one patient, greater than 90% (Near Complete Response) in second patient and greater than 50% (Partial Response) in third patient at Day 36 with cutaneous squamous cell carcinoma and (ii) that the Safety Monitoring Committee has issued a favorable review of safety data at the maximum dose of INTASYL PH-762. These patients completed treatment in the fifth and final dose cohort of Phio's ongoing Phase 1b dose escalation clinical trial (NCT 06014086).

The full text of the press release is attached hereto as Exhibit 99.1 and incorporated herein by reference.

**Item 9.01. Financial Statements and Exhibits.**

(d) Exhibits

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| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| 99.1 | [Press release issued by the Company on November 3, 2025.](ex_875368.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document). |

---

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**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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| | | |
|:---|:---|:---|
|  | **PHIO PHARMACEUTICALS CORP.** | **PHIO PHARMACEUTICALS CORP.** |
| Date: November 3, 2025 | By: | /s/ Robert J. Bitterman |
|  |  | Robert J. Bitterman<br> President & Chief Executive Officer |

---

## Exhibit 99.1

**Exhibit 99.1**

![logo.jpg](logo.jpg)

**Phio Pharmaceuticals Announces Positive Pathology Results:**

**Final Maximum Dose Cohort for INTASYL PH-762 Skin Cancer Trial** 

***Pathologic Clearance: 100% Tumor Clearance (Complete Response) in One Patient, Greater than 90% (Near Complete Response) in Second Patient, Greater than 50% (Partial Response) in Third Patient***

***Pathologic Results Assessed at Approximately 5 Weeks***

***Safety Monitoring Committee Issues Favorable Review of Safety Data at the Maximum Dose***

King of Prussia, Pennsylvania - (Newsfile Corp. – Nov 3, 2025) — Phio Pharmaceuticals Corp. (NASDAQ: PHIO) is a clinical-stage siRNA biopharmaceutical company developing therapeutics using its proprietary INTASYL® gene silencing technology to eliminate cancer. Phio announced today the pathologic results for three patients with cutaneous squamous cell carcinoma (cSCC) who completed treatment in the fifth and final dose cohort of Phio's on-going Phase 1b dose escalation trial: 100% tumor clearance in one of three patients, > 90% clearance in the second patient, and > 50% clearance in the third patient.

To date, a total of 18 patients with cutaneous carcinomas have completed treatment across five dose escalating cohorts in the Phase 1b trial. The cumulative pathologic response in 16 patients with cSCC include six with a complete response (100% clearance), two with a near complete response (> 90% clearance) and two with a partial response (> 50% clearance). A single patient with metastatic Merkel cell carcinoma had a partial response (> 50% clearance). Six patients with cSCC and one patient with metastatic melanoma had a pathologic non-response (< 50% clearance). No patients in the study have exhibited clinical progression of disease. Phio may continue to screen and treat additional patients as part of the fifth cohort.

The trial is designed to evaluate the safety and tolerability of neoadjuvant use of intratumoral PH-762 in Stages 1, 2 and 4 cutaneous squamous cell carcinoma (cSCC), Stage 4 melanoma, and Stage 4 Merkel cell carcinoma (NCT# 06014086). Per the trial's protocol, patients receive four injections of PH-762 at weekly intervals and pathologic response is assessed approximately 5 weeks after the initial injection of PH-762.

"The encouraging outcomes of intratumoral PH-762 in patients who have received treatment thus far is a significant step in clinical development and highlights the promise of a viable non-surgical alternative treatment for cutaneous carcinomas," said Robert Bitterman, CEO and Chairman of Phio Pharmaceuticals.

In addition, the Safety Monitoring Committee (SMC) completed its pre-specified review of safety results for the first three patients in the fifth cohort and confirmed that there were no dose-limiting toxicities or clinically relevant treatment-emergent adverse effects at this maximum dose concentration. Further, there have been no dose-limiting toxicities or clinically relevant treatment-emergent adverse effects in any of the patients who have completed treatment with intratumoral PH-762 in this trial.

"We are pleased with the continuing safety profile of PH-762 throughout dose escalation to approximately a 20-fold increase versus that received in the first cohort," said Mary Spellman, MD, Phio's acting Chief Medical Officer. "PH-762 has been well tolerated in this trial, without relevant immune-related adverse events or other toxicities."

**About Phio Pharmaceuticals Corp.**

Phio Pharmaceuticals Corp. (Nasdaq: PHIO) is a clinical-stage siRNA biopharmaceutical company advancing its INTASYL® gene silencing technology focused on immuno-oncology therapeutics. Phio's INTASYL compounds are designed to enhance the body's immune cells to more effectively kill cancer cells. Phio's lead clinical program is an INTASYL compound, PH-762, that silences the PD-1 gene implicated in various forms of skin cancer. The on-going Phase 1b trial (NCT# 06014086) is evaluating 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.

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

 **Forward Looking Statements**

*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. Examples of forward-looking statements contained in this press release include, among others, the possibility that our INTASYL*® *siRNA gene silencing technology will make the body*'*s immune cells more effective in killing cancer cells, our expectations with respect to the continued safety results of our clinical trial, our expectations with respect to the potential of a well-tolerated treatment for cutaneous carcinomas, and statements regarding our commercial and clinical strategy, development plans and timelines and other future events.*

*These statements 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 to our business and operations by inflationary pressures, rising interest rates, recession fears, the development of our product candidates, results from our 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 identified in our 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 SEC. 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.*

Contact:

&nbsp;&nbsp;&nbsp;&nbsp;Phio Pharmaceuticals Corp.

&nbsp;&nbsp;&nbsp;&nbsp;Jennifer Phillips: jphillips@phiopharma.com

&nbsp;&nbsp;&nbsp;&nbsp;Corporate Affairs