8-K

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): October 15, 2025

Prelude Therapeutics Incorporated

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (302)

467-1280

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

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:

☐ 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:

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.

On October 15 , 2025, Mardi Dier, a Class III member of the Board of Directors (the “Board”) of Prelude Therapeutics Incorporated (the “Company”), provided notice of her intention to resign from the Board, effective October 17, 2025 (the “Effective Date”). Ms. Dier's decision to resign was not the result of any disagreement with the Company on any matter relating to its operations, policies or practices.

On October 17, 2025, upon the recommendation of the Nominating and Corporate Governance Committee (the “NGC Committee”) of the Board, the Board appointed Katina Dorton, J.D., MBA, as a Class III director effective as of the Effective Date. Ms. Dorton also was appointed as a member of the Audit Committee of the Board, and will serve as Chair of the Audit Committee. Ms. Dorton will serve until the 2026 Annual Meeting of Stockholders and until her successor is duly elected and qualified or until her earlier resignation or removal.

Ms. Dorton most recently served as chief financial officer of NodThera, a private biotechnology company, from 2020 to 2022. Earlier in her career, she was a healthcare investment banker at Morgan Stanley and Needham & Company, and she practiced M&A and securities law at Sullivan and Cromwell. In addition, Ms. Dorton currently serves on the boards of directors of Fulcrum Therapeutics Inc. (Nasdaq: FULC) and TScan Therapeutics Inc. (Nasdaq: TCRX) positions she has held since 2019 and 2021, respectively. Ms. Dorton holds a Bachelor of Arts degree from Duke University, a Master of Business Administration degree from George Washington University and a Juris Doctor degree from the University of Virginia. Ms. Dorton’s qualifications to serve on our Board include her more than 30 years of finance and healthcare experience in leadership positions in areas of fundraising, mergers and acquisitions, and business development. There is no arrangement or understanding between Ms. Dorton and any other person pursuant to which Ms. Dorton was selected as a director. The Company is not aware of any related party transactions or relationships between Ms. Dorton and the Company that would require disclosure under Item 404(a) of Regulation S-K.

In connection with her appointment to the Board, and in accordance with the Company’s current director compensation policy, Ms. Dorton will receive compensation for her service as a director in accordance with the Company’s compensation policy for non-employee directors, and the Board granted Ms. Dorton non-incentive stock options (the “Options”) to purchase up to 76,000 shares of the Company’s common stock under the terms of the Company’s 2020 Equity Incentive Plan, with such Options vesting over a three year period equally one-thirty-sixth per month, subject to Ms. Dorton's continued service to the Company on each vesting date.

The Company will enter into an indemnity agreement with Ms. Dorton in the form that it has entered into with its other directors and that is filed as Exhibit 10.1 to the Company’s registration statement on Form S-1 (File No. 333-248628).

Item 7.01 Regulation FD Disclosure.

On October 17, 2025, the Company issued a press release announcing the appointment of Ms. Dorton to the Board. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

The information in this Current Report on Form 8-K and in Exhibit 99.1 attached hereto is being furnished, but shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (“Exchange Act”), and is not incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, regardless of any general incorporation language in such filing.

SIGNATURE

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

EX-99.1

Prelude Therapeutics Announces Appointment of Katina Dorton, J.D., MBA to its Board of Directors

WILMINGTON, Del., Oct. 17, 2025 (GLOBE NEWSWIRE) – Prelude Therapeutics Incorporated (Nasdaq: PRLD), a clinical-stage precision oncology company, today announced the appointment of Katina Dorton to its Board of Directors, effective today. Ms. Dorton has more than 30 years of industry expertise and leadership in healthcare and life sciences including service on several boards of public life science companies, executive financial leadership and investment banking.

“Katina brings to Prelude an abundance of experience as a strategic and financial advisor to our leadership team,” stated Kris Vaddi, Ph.D., Chief Executive Officer of Prelude. “We welcome her to our board and we look forward to her immediate contributions as we aim to advance our precision oncology drug candidates.”

Ms. Dorton was most recently Chief Financial Officer at NodThera. Prior to NodThera, she most recently built and led the finance organization for Repare Therapeutics, where she prepared the company for an IPO and raised more than $82 million in crossover funding. Ms. Dorton also served in senior finance roles at AVROBIO, Inc. and Immatics N.V. Prior to joining industry, Ms. Dorton spent 15 years as an investment banker with Morgan Stanley and Neeham & Co. Ms. Dorton currently serves on the board of directors at Mallinckrodt Pharmaceuticals plc, Fulcrum Therapeutics, TScan Therapeutics and Sonoma Biotherapeutics. Ms. Dorton received a B.A. from Duke University an M.B.A from George Washington University and a J.D. from University of Virgina School of Law.

“Prelude has an exciting pipeline of novel precision oncology drug candidates, a strong, experienced leadership team and the opportunity to create significant shareholder value,” stated Ms. Dorton. “I am excited for the opportunity to work closely with this team along with my fellow board members to help guide the company towards meeting its strategic goals.”

Ms. Dorton will succeed Mardi C. Dier, who will be resigning from the Prelude board effective October 17, 2025. Ms. Dorton will also succeed Ms. Dier as Audit Committee Chair at that time. Ms. Dier has served on Prelude’s board since August 2020.

“I want to take this moment to thank Mardi for her devoted service and invaluable contributions during her time on Prelude’s board,” continued Vaddi. “She has been an important resource to me professionally and others on our executive leadership team since becoming a public company in 2020. On behalf of the entire company, we wish Mardi continued success in her endeavors.”

About Prelude Therapeutics

Prelude Therapeutics is a leading precision oncology company developing innovative medicines in areas of high unmet need for cancer patients. Our pipeline is comprised of several novel drug candidates including first-in-class, highly selective SMARCA2 and KAT6A degraders, and ongoing research into other precision oncology targets. We are also leveraging our expertise in targeted protein degradation to discover, develop and commercialize next generation degrader antibody conjugates (Precision ADCs) with partners. We are on a mission to extend the promise of precision medicine to every cancer patient in need. Our corporate presentation can be found at Events & Presentations - Prelude Therapeutics. For more information, visit preludetx.com.

Cautionary Note Regarding Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to, anticipated discovery, preclinical and clinical development activities for Prelude’s product candidates, the potential safety, efficacy, benefits and addressable market for Prelude’s product candidates, the expected timeline for clinical trial results for Prelude’s product candidates, and the sufficiency of Prelude’s cash runway into the second quarter of 2026. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. The words “believes,” “anticipates,” “estimates,” “plans,” “expects,” “intends,” “may,” “could,” “should,” “potential,” “likely,” “projects,” “continue,” “will,” “schedule,” and “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements are predictions based on the Company’s current expectations and projections about future events and various assumptions. Although Prelude believes that the expectations reflected in such forward-looking statements are reasonable, Prelude cannot guarantee future events, results, actions, levels of activity, performance or achievements, and the timing and results of biotechnology development and potential regulatory approval is inherently uncertain. Forward-looking statements are subject to risks and uncertainties that may cause Prelude's actual activities or results to differ significantly from those expressed in any forward-looking statement, including risks and uncertainties related to Prelude's ability to advance its product candidates, the receipt and timing of potential regulatory designations, approvals and commercialization of product candidates, clinical trial sites and our ability to enroll eligible patients, supply chain and manufacturing facilities, Prelude’s ability to maintain and recognize the benefits of certain designations received by product candidates, the timing and results of preclinical and clinical trials, Prelude's ability to fund development activities and achieve development goals, Prelude's ability to protect intellectual property, and other risks and uncertainties described under the heading "Risk Factors" in Prelude’s Annual Report on Form 10-K for the year ended December 31, 2024, its Quarterly Reports on Form 10-Q and other documents that Prelude files from time to time with the Securities and Exchange Commission. These forward-looking statements speak only as of the date of this press release, and Prelude undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof, except as may be required by law.

Investor Contact: Robert A. Doody, Jr. Senior Vice President, Investor Relations

Prelude Therapeutics Incorporated

484.639.7235

rdoody@preludetx.com