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 11, 2025

Korro Bio, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (617)

468-1999

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:

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

The following is a summary of the matters voted on at the 2025 annual meeting of stockholders of Korro Bio, Inc., or Korro, held on June 11, 2025, or the Annual Meeting.

• Korro’s stockholders elected each of Ram Aiyar, Jean-François Formela and Katharine Knobil as Class III directors, each for a three-year term ending at the annual meeting of stockholders to be held in 2028 and each until his or her respective successor has been duly elected and qualified or until his or her earlier death, resignation or removal. The results of the stockholders’ vote with respect to the election of the three Class III directors are as follows:

• Korro’s stockholders approved, in a non-binding, advisory vote, the compensation of Korro’s named executive officers. The results of the stockholders’ advisory vote with respect to the compensation of Korro’s named executive officers are as follows:

• Korro’s stockholders approved, in a non-binding, advisory vote, the “1 Year” option for the frequency of future advisory votes on the compensation of Korro’s named executive officers. The results of the stockholders’ advisory vote with respect to the frequency of future advisory votes on the compensation of Korro’s named executive officers are as follows:

• Korro’s stockholders ratified the selection of Ernst & Young LLP as its independent registered public accounting firm for the fiscal year ending December 31, 2025. The results of the stockholders’ vote with respect to such ratification are as follows:

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.