Form 8-K

8-K — Phio Pharmaceuticals Corp.

Accession: 0001437749-26-023916

Filed: 2026-07-21

Period: 2026-07-21

CIK: 0001533040

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — phio20260717_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (ex_989635.htm)

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0001533040

2026-07-21

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): July 21, 2026

PHIO PHARMACEUTICALS CORP.

(Exact name of registrant as specified in its charter)

Delaware

001-36304

45-3215903

(State or other jurisdiction of incorporation)

(Commission File Number)

(I.R.S. Employer Identification No.)

411 Swedeland Road, Suite 23-1080

King of Prussia, PA

19406

(Address of principal executive offices)

(Zip Code)

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:

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

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. ☐

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Effective as of July 20, 2026, the Board of Directors (the “Board”) of Phio Pharmaceuticals Corp. (the “Company”) increased the size of the Board to six members and appointed R. Todd Plott, M.D. to serve on the Board until the 2026 annual meeting of stockholders. Dr. Plott was also appointed to serve as a member of the Board’s Governance Committee. Dr. Plott is a board-certified dermatologist, accomplished researcher, inventor, and former FDA advisory committee member with more than 30 years of experience in dermatologic care and innovation.

In connection with Dr. R. Todd Plott, M.D.’s appointment to the Board, Dr. R. Todd Plott, M.D. will enter into the Company’s standard form of indemnification agreement. Pursuant to the terms of the indemnification agreement, the Company may be required, among other things, to indemnify Dr. R. Todd Plott, M.D. for some expenses, including attorneys’ fees, judgments, fines and settlement amounts incurred by him in any action or proceeding arising out of his service on the Board. In addition, Dr. R. Todd Plott, M.D. will receive standard compensation and equity awards available to non-employee directors of the Company. The Company’s non-employee director compensation program is described in the “Director Compensation” section of the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (the “SEC”) on March 5, 2026.

There are no arrangements or understandings between Dr. R. Todd Plott, M.D. and any other persons, pursuant to which Dr. R. Todd Plott, M.D. was appointed to the Board. There are no current or proposed transactions between the Company and Dr. R. Todd Plott, M.D. or his immediate family members that would require disclosure under Item 404(a) of Regulation S-K promulgated by the SEC.

Item 8.01. Other Events.

On July 21 2026, the Company issued a press release announcing the appointment of Dr. R. Todd Plott, M.D. to the Board of Directors.

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

Exhibit No.

Description

99.1

Press release issued by the Company on July 21, 2026.

104

Cover Page Interactive Data File (embedded within the Inline XBRL document).

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.

PHIO PHARMACEUTICALS CORP.

Date: July 21, 2026

By:

/s/ Robert J. Bitterman

Robert J. Bitterman

President & Chief Executive Officer

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: ex_989635.htm · Sequence: 2

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Exhibit 99.1

Phio Pharmaceuticals Announces Appointment of Dr. R. Todd Plott to the Board of Directors

Brings extensive experience in patient care, dermatologic research and commercialization

KING OF PRUSSIA, Pennsylvania-(Newsfile Corp.-July 21, 2026) — 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 is pleased to announce that R. Todd Plott, M.D. has been appointed to the Board of Directors of Phio Pharmaceuticals

Todd Plott, MD, is a board-certified dermatologist, accomplished researcher, inventor, and former FDA advisory committee member with more than 30 years of experience in dermatologic care and innovation. He has played a significant role in advancing treatments for acne and other skin conditions through pharmaceutical research and development. Throughout his career, Dr. Plott oversaw and monitored hundreds of clinical trials, building deep expertise in drug development, clinical research, and patient care. He is now in private practice, focusing on complex skin diseases, acne, and skin cancer. Dr. Plott also served on the FDA Dermatologic and Ophthalmic Drug Advisory Committee from 2016 to 2021, reflecting his leadership and influence in the field of dermatology.

“Dr. Plott’s exceptional experience through his dermatology practice as well as clinical development expertise provides a valuable resource to Phio as we advance PH-762 for squamous cell carcinoma,” said Robert Bitterman, CEO and Chairman of the Board.

About Phio Pharmaceuticals Corporation

Phio Pharmaceuticals Corp. (Nasdaq: PHIO) is a clinical-stage biopharmaceutical company advancing its proprietary INTASYL® 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.

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. These statements, which include statements, among other things, regarding the anticipated benefits of our INTASYL™ RNAi platform, the results from our ongoing clinical trials, our expectations regarding timing of FDA submissions intended to propose and seek guidance for next steps in clinical study design for PH-762, our expectations that such FDA submissions and any related FDA meetings will clarify next steps in advancing the PH-762 development program, 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.

Contact:

Phio Pharmaceuticals Corp.

Jennifer Phillips: jphillips@phiopharma.com

Corporate Affairs

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