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): February 6, 2023

ATYR PHARMA, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (858) 731-8389

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 obligations 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 or Rule 12b-2 of the Securities Exchange Act of 1934.

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 8.01 Other Events.

On February 6, 2023, aTyr Pharma, Inc. (the “Company”) announced that its partner Kyorin Pharmaceutical Co., Ltd, a wholly owned subsidiary of Kyorin Holdings, Inc. (“Kyorin”), has dosed the first patient in Japan in EFZO-FIT™, a global pivotal Phase 3 study to evaluate the efficacy and safety of the Company’s lead therapeutic candidate, efzofitimod, in patients with pulmonary sarcoidosis, a major form of interstitial lung disease (“ILD”). This achievement has triggered a $10.0 million milestone payment by Kyorin to the Company pursuant to a collaboration and license agreement between the Company and Kyorin (the “Kyorin Agreement”). Kyorin is the Company’s partner for the development and commercialization of efzofitimod for ILD in Japan. Under the Kyorin Agreement, the Company has generated $20.0 million in upfront and milestone payments to date and is eligible to receive up to an additional $155.0 million in the aggregate upon the achievement of certain development, regulatory and sales milestones, as well as tiered royalties on any net sales in Japan. Kyorin has the exclusive rights to develop and commercialize efzofitimod in Japan for all forms of ILD.

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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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