Initial Registration Statement for Employee Benefit Plan (Form S-8)

As filed with the U.S. Securities and Exchange Commission on August 7, 2026

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ATYR PHARMA, INC.

(Exact name of registrant as specified in its charter)

10240 Sorrento Valley Road, Suite 300

San Diego, CA 92121

(Address of Principal Executive Offices) (Zip Code)

ATYR PHARMA, INC. 2015 STOCK OPTION AND INCENTIVE PLAN, AS AMENDED

(Full titles of the plans)

Sanjay S. Shukla, M.D., M.S.

President, Chief Executive Officer and Director

10240 Sorrento Valley Road, Suite 300

San Diego, CA 92121

(858) 731-8389

(Name and address of agent for service) (Telephone number, including area code, of agent for service)

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

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 7(a)(2)(B) of the Securities Act. 

EXPLANATORY NOTE

This Registration Statement on Form S-8 (the "Registration Statement") is being filed by aTyr Pharma, Inc. (the "Registrant") for the purpose of registering 4,000,000 additional shares of the Registrant's common stock, par value $0.001 per share ("Common Stock"), issuable pursuant to the Registrant's 2015 Stock Option and Incentive Plan, as amended (the "2015 Plan"), pursuant to an amendment to the 2015 Plan approved by the stockholders of the Registrant on May 11, 2026.

INCORPORATION OF DOCUMENTS BY REFERENCE

The Registrant previously registered shares of its Common Stock for issuance under the 2015 Plan under Registration Statements on Form S-8 filed with the Securities and Exchange Commission (the "Commission") on May 7, 2015 (File No. 333-203955), April 1, 2016 (File No. 333-210543), March 22, 2017 (File No. 333-216880), March 23, 2018 (File No. 333-223865), May 20, 2019 (File No. 333-231594), August 18, 2020 (File No. 333-248090), May 14, 2021 (File No. 333-256145), May 11, 2022 (File No. 333-264866), August 10, 2023 (File No. 333-273876), August 13, 2024 (File No. 333-281525) and August 7, 2025 (File No. 333-289364).

This Registration Statement is being filed for the purpose of registering additional securities of the same class as other securities for which Registration Statements of the Registrant on Form S-8 relating to the same employee benefit plans are effective.

Pursuant to General Instruction E to Form S-8, this Registration Statement hereby incorporates by reference the contents of the registration statements referenced above and the description of the Registrant's Common Stock which is contained in a Registration Statement on Form 8-A filed with the Commission on May 6, 2015 (File No. 001-37378) under Section 12(b) of the Securities Exchange Act of 1934, as amended, including any amendment or report filed for the purpose of updating such description, including Exhibit 4.6 to the Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2023, as filed with the Commission on March 14, 2024.

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Item 8. Exhibits.

The exhibits to this Registration Statement are listed below:

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Diego, State of California, this 7th day of August, 2026.

POWER OF ATTORNEY AND SIGNATURES

We, the undersigned officers and directors of aTyr Pharma, Inc., hereby severally constitute and appoint Sanjay S. Shukla, M.D., M.S. and Jill M. Broadfoot, and each of them singly (with full power to each of them to act alone), our true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution in each of them for their and in their name, place and stead, and in any and all capacities, to sign for us and in our names in the capacities indicated below any and all amendments (including post-effective amendments) to this registration statement on Form S-8, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises, as full to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the date indicated below.

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