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): June 3, 2025

VoyagerTherapeutics, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code:

(857

) 259-5340

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; Electionof Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

At the annual meeting of stockholders of Voyager Therapeutics, Inc. (“Voyager”) held on June 3, 2025 (the “2025 Annual Meeting”), Voyager’s stockholders approved the 2025 Stock Incentive Plan (the “2025 Stock Incentive Plan”) and the Amended and Restated 2015 Employee Stock Purchase Plan (the “Amended and Restated 2015 Employee Stock Purchase Plan”), each of which had previously been adopted by Voyager’s Board of Directors subject to stockholder approval.

Descriptions of the 2025 Stock Incentive Plan contained on pages 12 to 26 and the Amended and Restated 2015 Employee Stock Purchase Plan contained on pages 27 to 31 of Voyager’s Proxy Statement for the 2025 Annual Meeting, filed with the Securities and Exchange Commission on April 23, 2025, are incorporated herein by reference. Complete copies of the 2025 Stock Incentive Plan and the Amended and Restated 2015 Employee Stock Purchase Plan are attached hereto as Exhibits 99.1 and 99.2, respectively, and are incorporated herein by reference.

Item 5.07. Submission of Matters to a Vote of Security Holders.

The following is a summary of the matters voted on at the 2025 Annual Meeting.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

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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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