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): March 26, 2018

AEGLEA BIOTHERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

(512) 942-2935

(Registrant’s telephone number, including area code)

(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:

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. ☒

On March 22, 2018, the Board of Directors (the “Board”) of Aeglea BioTherapeutics, Inc. (the “Company”) appointed Ivana Magovcevic-Liebisch as a Class II director and a member of the Audit Committee of the Board, effective as of the same date.

Dr. Magovcevic-Liebisch will receive an annual cash retainer of $37,500 per year in accordance with the Company’s existing compensation policy for non-employee directors. In addition, the Board granted to Dr. Magovcevic-Liebisch, effective March 22, 2018, a stock option to purchase 36,800 shares of common stock at an exercise price of $10.50 per share, which will vest monthly over three years, subject to Dr. Magovcevic-Liebisch’s continued service to the Company.

The Company has entered into its standard form of indemnification agreement with Dr. Magovcevic-Liebisch. A form of the indemnification agreement was previously filed by the Company as Exhibit 10.1 to the Company’s Registration Statement on Form S-1 filed with the Securities and Exchange Commission on September 14, 2015.

There is no arrangement or understanding with any person pursuant to which Dr. Magovcevic-Liebisch was appointed as a member of the Board, and Dr. Magovcevic-Liebisch does not have any direct or indirect material interest in any transaction required to be disclosed pursuant to Item 404(a) of Regulation S-K.

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SIGNATURE

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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