LXEO

8-K

0001907108false00019071082025-11-052025-11-05

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 05, 2025

Lexeo Therapeutics, Inc. (Exact name of Registrant as Specified in Its Charter)

Delaware

001-41855

85-4012572

(State or Other Jurisdiction of Incorporation)

(Commission File Number)

(IRS Employer Identification No.)

345 Park Avenue South, Floor 6

New York, New York

10010

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: 212 547-9879

N/A

(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:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, $0.0001 par value per share

LXEO

Nasdaq Global 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 2.02 Results of Operations and Financial Condition.

On November 5, 2025, Lexeo Therapeutics, Inc. (the “Company”) issued a press release announcing business highlights and its financial results for the three and nine months ended September 30, 2025. A copy of this press release is furnished herewith as Exhibit 99.1 to this Current Report and is incorporated herein by reference.

The information in this Item 2.02 and Exhibit 99.1 hereto shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any of the Company’s filings under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such a filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit Number

Description

99.1

Press Release

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.

Lexeo Therapeutics, Inc.

Date:

November 5, 2025

By:

/s/ R. Nolan Townsend

R. Nolan Townsend, Chief Executive Officer

8-K

false 0001907108 0001907108 2025-10-16 2025-10-16

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 16, 2025

Lexeo Therapeutics, Inc. (Exact name of registrant as specified in its charter)

Delaware

001-41855

85-4012572

(State or other jurisdiction of incorporation or organization)

(Commission File Number)

(I.R.S. Employer Identification Number)

345 Park Avenue South, Floor 6 New York, New York

10010

(Address of principal executive offices)

(Zip Code) (212) 547-9879 (Registrant’s telephone number, including area code) N/A (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:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, $0.0001 par value per share

LXEO

Nasdaq Global 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) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2). 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 1.01 Entry into a Material Definitive Agreement.

Underwriting Agreement On October 16, 2025, Lexeo Therapeutics, Inc. (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with Leerink Partners LLC, as representative (the “Representative”) of the several underwriters named therein (collectively, the “Underwriters”), relating to the issuance and sale in a public offering (the “Public Offering”) of 15,625,000 shares (the “Firm Shares”) of the Company’s common stock, par value $0.0001 per share (the “Common Stock”), at a price to the public of $8.00 per share. Under the terms of the Underwriting Agreement, the Underwriters have agreed to purchase the Firm Shares from the Company at a price of $7.52 per share. In addition, the Company has granted the Underwriters an option, exercisable for 30 days from the date of the Underwriting Agreement, to purchase up to an additional 2,343,750 shares of common stock (together with the Firm Shares, the “Shares”) at the public offering price, less underwriting discounts and commissions. All of the Shares in the Public Offering are being sold by the Company. The gross proceeds from the Public Offering are expected to be approximately $125 million before deducting underwriting discounts and commissions and other offering expenses payable by the Company and assuming no exercise of the Underwriters’ option to purchase additional shares. The Public Offering is expected to close on October 20, 2025, subject to the satisfaction of customary closing conditions. The Underwriting Agreement contains customary representations, warranties and agreements by the Company, customary conditions to closing, indemnification obligations of the Company and the Underwriters, including for liabilities under the Securities Act of 1933, as amended (the “Securities Act”), other obligations of the parties, and termination provisions. The representations, warranties and covenants contained in the Underwriting Agreement were made only for purposes of such agreement and as of specific dates, were solely for the benefit of the parties to such agreement, and may be subject to limitations agreed upon by such parties. The Public Offering is being made pursuant to the Company’s effective registration statement on Form S-3 (File No. 333-283781) (the “Registration Statement”) and a related prospectus and prospectus supplement, in each case filed with the Securities and Exchange Commission (the “SEC”). The foregoing description of the Underwriting Agreement does not purport to be complete and is qualified in its entirety by reference to the Underwriting Agreement, which is attached as Exhibit 1.1 to this Current Report on Form 8-K and is incorporated herein by reference. A copy of the opinion of Wilson Sonsini Goodrich & Rosati, P.C. relating to the validity of the Shares is filed as Exhibit 5.1 hereto and is incorporated by reference into the Registratio

8-K

0001907108false00019071082025-08-142025-08-14

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): August 14, 2025

Lexeo Therapeutics, Inc. (Exact name of Registrant as Specified in Its Charter)

Delaware

001-41855

85-4012572

(State or Other Jurisdiction of Incorporation)

(Commission File Number)

(IRS Employer Identification No.)

345 Park Avenue South, Floor 6

New York, New York

10010

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: 212 547-9879

N/A

(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:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, $0.0001 par value per share

LXEO

Nasdaq Global 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 2.02 Results of Operations and Financial Condition.

On August 14, 2025, Lexeo Therapeutics, Inc. (the “Company”) issued a press release announcing business highlights and its financial results for the three and six months ended June 30, 2025. A copy of this press release is furnished herewith as Exhibit 99.1 to this Current Report and is incorporated herein by reference.

The information in this Item 2.02 and Exhibit 99.1 hereto shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any of the Company’s filings under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such a filing.

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

CFO Transition

On August 14, 2025, Lexeo Therapeutics, Inc. (the “Company”) announced that the Board of Directors of the Company (the “Board”) appointed Louis Tamayo to serve as the Company’s Chief Financial Officer effective August 15, 2025 (the “Effective Date”). In connection with Mr. Tamayo’s appointment as Chief Financial Officer, Mr. Tamayo will also serve as the Company’s principal financial officer and principal accounting officer. Mr. Tamayo succeeds Dr. Kyle Rasbach, who resigned as Chief Financial Officer effective August 15, 2025. Dr. Rasbach will serve as an advisor to the Company through August 29, 2025 to assist in the transition of his duties. The Company is appreciative of the service of Dr. Rasbach and his resignation is not the result of any disagreement with the Company on any matter, including the Company’s operations, policies or practices.

Prior to joining the Company, Mr. Tamayo, age 49, served as the Senior Vice President – Operational Excellence at Siemens Healthineers AG from February 2023 to September 2024. He also served as Senior Vice President – Head of Product Franchise Finance at Siemens Healthineers AG from October 2020 to February 2023. From 2016 to October 2020, Mr. Tamayo served as the Vice President – Head of Research and Development Finance (Product Lifecycle Management) at Siemens Healthineers AG. From 2014 to 2016, Mr. Tamayo served as the Vice President – Business Unit Chief Financial Officer, Diabetes Care at Becton, Dickinson and Company. Mr. Tamayo previously held various senior leadership roles at Pfizer from 2000 to 2014, including Senior Director – Regional Head of Strategy and Analytics, Regional Finance Director – US Primary Care, and Director – Asia-Pacific Finance Program Office. Mr. Tamayo holds a B.B.A. in Finance and Marketing from Northeastern University.

In connection with his appointment as Chief Financial Off