# EDGAR Filing Document

**Accession Number:** 0001339970
**File Stem:** 0001193125-25-202865
**Filing Date:** 2025-9
**Character Count:** 20925
**Document Hash:** c4d62cdea113c58278477084b5b120d5
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-202865.hdr.sgml**: 20250915

**ACCESSION NUMBER**: 0001193125-25-202865

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 22

**CONFORMED PERIOD OF REPORT**: 20250915

**ITEM INFORMATION**: Other Events

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20250915

**DATE AS OF CHANGE**: 20250915

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** aTYR PHARMA INC
- **CENTRAL INDEX KEY:** 0001339970
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 203435077
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-37378
- **FILM NUMBER:** 251313265

**BUSINESS ADDRESS:**
- **STREET 1:** 10240 SORRENTO VALLEY ROAD
- **STREET 2:** SUITE 300
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121
- **BUSINESS PHONE:** 8587318389

**MAIL ADDRESS:**
- **STREET 1:** 10240 SORRENTO VALLEY ROAD
- **STREET 2:** SUITE 300
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121

?xml version='1.0' encoding='ASCII'? 8-K

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**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

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**FORM** 8-K

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**CURRENT REPORT** 

**Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934** 

**Date of Report (Date of earliest event reported):** **September 15, 2025**

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ATYR PHARMA, INC.

**(Exact name of registrant as specified in its charter)** 

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| | | |
|:---|:---|:---|
| Delaware | 001-37378 | 20-3435077 |
| **(State or other jurisdiction**<br>**of incorporation)** | **(Commission File Number)** | **(IRS Employer**<br>**Identification No.)**<br>|
| 10240 Sorrento Valley Road**,** Suite 300<br>San Diego**,** CA |  | 92121 |
| **(Address of principal executive offices)** |  | **(Zip Code)** |

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

**Not Applicable**

**(Former name or former address, if changed since last report)** 

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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:

☐ 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:**

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| | | |
|:---|:---|:---|
| &nbsp;&nbsp;**Title of each class** | &nbsp;&nbsp;**Trading Symbol(s)** | &nbsp;&nbsp;**Name of each exchange on which registered** |
| &nbsp;&nbsp;Common Stock, par value $0.001 per share | &nbsp;&nbsp;ATYR | &nbsp;&nbsp;The Nasdaq Capital Market |

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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. ☐

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**Item 8.01 Other Events.**

On September 15, 2025, aTyr Pharma, Inc. (the "Company") announced topline results from its Phase 3 EFZO-FIT™ study of efzofitimod in 268 patients with pulmonary sarcoidosis, a major form of interstitial lung disease. The study did not meet its primary endpoint of change from baseline in mean daily oral corticosteroid ("OCS") dose at week 48. The change from baseline in mean daily OCS dose reduced to an average of 2.79 mg for 5.0 mg/kg efzofitimod vs 3.52 mg for placebo (p=0.3313). The study's statistical analysis plan was designed on a hierarchical assessment basis, as such since the primary endpoint was not met, all subsequent statistical testing is reported as nominal findings. The study demonstrated a clinical improvement in the King's Sarcoidosis Questionnaire ("KSQ")-Lung score at week 48 for 5.0 mg/kg efzofitimod compared to placebo (p=0.0479), with a responder analysis of patients who achieved complete steroid withdrawal at week 48 with an improved KSQ-Lung score also showing improvement in patients treated with 5.0 mg/kg efzofitimod compared to placebo (p=0.0199). Lung function as measured by forced vital capacity ("FVC") at week 48 was maintained.

Based on these findings, which the Company believes indicate drug activity for efzofitimod as evidenced by improvements across multiple clinically relevant efficacy endpoints, the Company plans to engage with the U.S. Food and Drug Administration (FDA) to review the results and determine the path forward for efzofitimod in pulmonary sarcoidosis.

EFZO-FIT*™* was a global Phase 3 interventional study in 268 patients with pulmonary sarcoidosis that compared the efficacy and safety of efzofitimod at 3.0 mg/kg and 5.0 mg/kg doses versus placebo after 48 weeks of treatment, which included a protocol guided steroid taper in the first 12 weeks of the study, followed by continued taper or rescue until week 48.

Presented below are the families of endpoints analyzed in the study. As the primary endpoint did not achieve statistical significance, p-values for other endpoints are reported and should be interpreted as nominal p-values.

**Study Outcome Measures at Week 48**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;•**Steroid Reduction**

oPrimary Endpoint: Change from baseline in mean daily OCS dose to an average of 2.79 mg for 5.0 mg/kg efzofitimod vs 3.52 mg for placebo (p=0.3313)

oComplete steroid withdrawal achieved for 52.6% of patients treated with 5.0 mg/kg efzofitimod vs 40.2% on placebo (p=0.0919)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;•**KSQ-Lung Score**

oChange from baseline in KSQ-Lung score of 10.36 for 5.0 mg/kg efzofitimod vs 6.19 for placebo (p=0.0479)

oProportion of patients who achieved complete steroid withdrawal with stable KSQ-Lung score was 46.9% of patients on 5.0 mg/kg of efzofitimod vs 35.7% on placebo (p=0.1241)

oProportion of patients who achieved complete steroid withdrawal with KSQ-Lung improvement was 29.5% of patients on 5.0 mg/kg efzofitimod vs 14.4% in placebo (p=0.0199)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;•**FVC**

oChange from baseline in absolute percent predicted FVC of -1.81 for patients in the 5.0 mg/kg efzofitimod vs -2.11 in placebo (p=0.7875)

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;•**Safety and Tolerability**

oGenerally well-tolerated at both the 3.0 mg/kg and 5.0 mg/kg doses, consistent with previously observed safety profile in all trials conducted to date

On September 15, 2025, the Company will host a conference call and webcast to discuss the results. A corporate presentation regarding the results is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

**Forward-Looking Statements**

Certain statements contained in this report are forward-looking statements that involve a number of risks and uncertainties. Such forward-looking statements include, without limitation, statements regarding the potential therapeutic benefits and applications of efzofitimod; potential drug activity for efzofitimod; and plans to engage the FDA to determine a path forward for efzofitimod in pulmonary sarcoidosis as well as the Company's expectations with respect to the outcome of that meeting and next steps for the development of efzofitimod in pulmonary sarcoidosis. Words such as "believes," "plans," "will" and similar expressions are intended to identify forward-looking statements, though not all forward-looking statements necessarily contain these identifying words. The inclusion of forward-looking statements should not be regarded as a representation by the Company that any of these results will be achieved. Actual results may differ materially from those set forth in this report due to the risks and uncertainties associated with research and development of pharmaceutical product candidates, as well as risks and uncertainties inherent in the Company's business. Additional factors that could cause actual results to differ materially from those stated in or implied by the Company's forward-looking statements are disclosed in its other filings with the U.S. Securities and Exchange Commission, including in the section captioned "Risk Factors" in the Company's most recent Annual Report on Form 10-K and subsequently filed Quarterly Reports on Form 10-Q. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and the Company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof, except as required by law. All forward-looking statements are qualified in their entirety by this cautionary statement. This caution is made under the safe harbor provisions of Section 21E of the Private Securities Litigation Reform Act of 1995.

**Item 9.01 Financial Statements and Exhibits.** 

(d) Exhibits

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| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| 99.1 | [<u>aTyr Pharma, Inc. Corporate Presentation dated September 15, 2025</u>](atyr-ex99_1.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document) |

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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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| | | |
|:---|:---|:---|
|  | **ATYR PHARMA, INC.** | **ATYR PHARMA, INC.** |
|  | By: | /s/ Jill M. Broadfoot |
|  |  | Jill M. Broadfoot |
|  |  | Chief Financial Officer |
| Date: September 15, 2025<br>|  |  |

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## Exhibit 99.1

![Slide 1](atyr-ex99_1s1.jpg)

A New Approach to Interstitial Lung Disease Topline Results for Phase 3 EFZO-FIT™ Study of Efzofitimod in Pulmonary Sarcoidosis September 15, 2025 Exhibit 99.1

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![Slide 2](atyr-ex99_1s2.jpg)

Forward Looking Statements The following slides and any accompanying oral presentation contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and other federal securities laws. The use of words such as "may," "might," "will," "should," "expect," "plan," "anticipate," "believe," "estimate," "project," "intend," "future," "potential," "opportunity," or "continue," and other similar expressions are intended to identify forward-looking statements. For example, all statements regarding: the potential therapeutic benefits of proteins derived from tRNA synthetase genes and our product candidates and development programs; the ability to successfully advance our product candidates and undertake certain development activities (such as the initiation of clinical trials, clinical trial enrollment, the conduct of clinical trials and announcement of clinical results) and accomplish certain development goals, and the timing of such events; the potential market opportunity for our product candidates; our ability to receive regulatory approvals for, and commercialize, our product candidates; our ability to identify and discover additional product candidates; potential activities and payments under collaboration agreements; and the ability of our intellectual property portfolio to provide protection are forward-looking statements. All forward-looking statements are based on estimates and assumptions by our management that, although we believe to be reasonable, are inherently uncertain. All forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially from those that we expected. These risks, uncertainties and other factors are more fully described in our filings with the U.S. Securities and Exchange Commission, including our Annual Report on Form 10-K, our subsequently filed Quarterly Reports on Form 10-Q, and in our other filings. The forward-looking statements in this presentation speak only as of the date of this presentation and neither we nor any other person assume responsibility for the accuracy and completeness of any forward-looking statement. We undertake no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law. We own various U.S. federal trademark applications and unregistered trademarks, including our company name. All other trademarks or trade names referred to in this presentation are the property of their respective owners. Solely for convenience, the trademarks and trade names in this presentation are referred to without the symbols® and™, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. This presentation discusses product candidates that are under clinical study and which have not yet been approved for marketing by the U.S. Food and Drug Administration. No representation is made as to the safety or effectiveness of these product candidates for the uses for which they are being studied. This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties and us.

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![Slide 3](atyr-ex99_1s3.jpg)

Summary of Key Findings Study did not meet primary endpoint in change from baseline in mean daily OCS dose at week 48 52.6% of patients treated with 5.0 mg/kg efzofitimod achieved complete steroid withdrawal at week 48 vs 40.2% on placebo (p=0.0919) Clinical improvement in KSQ-Lung score at week 48 observed in the 5.0 mg/kg efzofitimod treatment group vs placebo (p=0.0479). Greater proportion of patients achieved complete steroid withdrawal at week 48 with a KSQ-Lung score improvement in the 5.0 mg/kg efzofitimod treatment group (29.5%) vs placebo (14.4%) (p=0.0199) Lung function as measured by forced vital capacity (FVC) at week 48 was maintained Efzofitimod was generally well-tolerated at both the 3.0 mg/kg and 5.0 mg/kg doses, consistent with a previously observed safety profile in all trials conducted to date OCS = oral corticosteroids; KSQ = King's Sarcoidosis Questionnaire; FDA = Food and Drug Administration As the primary endpoint did not achieve statistical significance, p-values for other endpoints should be interpreted as nominal p-values. Findings demonstrate drug activity for efzofitimod across multiple clinically relevant efficacy endpoints Company plans to engage with the U.S. FDA to determine the path forward for efzofitimod in pulmonary sarcoidosis

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![Slide 4](atyr-ex99_1s4.jpg)

Global Phase 3 Trial in Pulmonary Sarcoidosis Population: moderate to severe pulmonary sarcoidosis Diagnosis of pulmonary sarcoidosis for ≥ 6 months Stable treatment with ≥ 7.5 and ≤ 25 mg/day OCS Extent of fibrosis < 20% Symptomatic with KSQ-Lung score ≤ 70 Steroid Taper Protocol Guidelines Based on Patients Global Assessment (PGA) and Investigator Assessment (IA) conducted every two weeks If both PGA and IA are stable or improved, patient OCS will need to be tapered; If either PGA or IA has worsened, patient will be rescued with OCS 0 4 8 12 16 20 24 28 Efzofitimod 5 mg/kg (n=88) once monthly IV dosing Efzofitimod 3 mg/kg (n=88) once monthly IV dosing Placebo (n=88) once monthly IV dosing Week Dosing 1:1:1 Randomization Treatment Follow-up Primary objective: Assess the efficacy of efzofitimod in patients with pulmonary sarcoidosis 32 36 40 44 48 52 Begin OCS taper End OCS taper Primary Endpoint N = 268 patients in U.S., Europe, Japan and Brazil Individual Patient Expanded Access Program (EAP) is intended to allow access for patients who complete EFZO-FIT™ and wish to receive treatment with efzofitimod outside of the clinical trial

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![Slide 5](atyr-ex99_1s5.jpg)

Steroid Reduction 1Missing patients considered non-responders; 2Adjusted percentage; Tables 14.2.1.2.1, 14.2.2.2.1; rounded to closest first decimal Week 48 Placebo N=90 Efzofitimod 3 mg/kg N=86 Efzofitimod 5 mg/kg N=88 N 81 77 83 LS mean dose at week 48 (mg) 3.5 3.5 2.8 LS mean change from baseline (mg) Difference in LS mean (95% CI) Nominal p-value -7.1 - - -7.1 0.0 (-1.5, 1.5) 0.9804 -7.9 -0.7 (-2.2, 0.8) 0.3313 Steroid free1; n (%2) Odds ratio (95% CI) Nominal p-value 36 (40.2) - - 45 (51.8) 1.6 (0.9, 3.0) 0.1172 46 (52.6) 1.7 (0.9, 3.1) 0.0919 The percent change from baseline was -63.3% for placebo, -67.8% for efzofitimod 3 mg/kg and -73.6% for efzofitimod 5 mg/kg

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![Slide 6](atyr-ex99_1s6.jpg)

King's Sarcoidosis Questionnaire (KSQ)-Lung and Composites 1stable = >-3; 2missing patients treated as non-responders; 3adjusted percentage; 4improved = ≥8; 5raw percentage; Source: Tables 14.2.6.3, 14.2.3.1, Draft output for steroid free and improved; rounded to closest first decimal Week 48 Placebo N=90 Efzofitimod 3 mg/kg N=86 Efzofitimod 5 mg/kg N=88 N 81 77 83 LS mean week 48 score 57.7 58.8 61.8 LS mean change from baseline Difference; LS mean (95% CI) Nominal p-value 6.2 - - 7.3 1.1 (-3.1, 5.4) 0.5932 10.4 4.2 (0.0, 8.3) 0.0479 Steroid free and stable1 KSQ-L2; n (%3) Odds ratio (95% CI) Nominal p-value 32 (35.7) - - 42 (48.3) 1.7 (0.9, 3.2) 0.0848 41 (46.9) 1.6 (0.9, 3.0) 0.1241 Steroid free and improved4 KSQ-L2; n (%5) Odds ratio (95% CI) Nominal p-value 13 (14.4) - - 24 (27.9) 2.2 (1.0, 4.7) 0.0402 26 (29.5) 2.4 (1.2, 5.1) 0.0199

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![Slide 7](atyr-ex99_1s7.jpg)

Forced Vital Capacity (FVC) 1GLI global; Tables 14.2.4.2.1, Draft output for FVC % predicted; rounded to closest first decimal Week 48 Placebo N=90 Efzofitimod 3 mg/kg N=86 Efzofitimod 5 mg/kg N=88 N 74 67 74 FVC (mL), LS mean 3380.4 3369.7 3395.4 LS mean change from baseline (mL) Difference in LS means (mL) (95% CI) Nominal p-value -84.5 - - -95.1 -10.6 (-104.7, 83.5) 0.8244 -69.4 15.1 (-77.4, 107.6) 0.7485 FVC % predicted1; LS mean 86.7 86.1 87.0 LS mean change from baseline (% predicted) Difference in LS means (mL) (95% CI) Nominal p-value -2.1 - - -2.7 -0.6 (-2.8, 1.6) 0.5855 -1.8 0.3 (-1.9, 2.5) 0.7875

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![Slide 8](atyr-ex99_1s8.jpg)

Safety and Tolerability Efzofitimod was generally well-tolerated at both the 3.0 mg/kg and 5.0 mg/kg doses, consistent with a previously observed safety profile in all trials conducted to date Adverse events (AEs) were mostly mild or moderate in severity and generally assessed as unrelated to the study drug Serious adverse events (SAEs) were limited and balanced between treatment groups Proportion of patients with treatment-related SAEs and events leading to discontinuation was small and balanced between treatment groups. Proportion of patients who developed antidrug antibodies was small and balanced between treatment groups

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![Slide 9](atyr-ex99_1s9.jpg)

Key Takeaways and Next Steps Evidence of drug activity observed for 5.0 mg/kg efzofitimod across multiple clinically relevant efficacy endpoints Clinical improvement in quality of life as measured by the KSQ-Lung for 5.0 mg/kg efzofitimod vs placebo Preservation of lung function with efzofitimod 5.0 mg/kg Generally well-tolerated at both the 3.0 mg/kg and 5.0 mg/kg doses, consistent with a previously observed safety profile in all trials conducted to date Planned Next Steps Present EFZO-FIT™ topline results at the European Respiratory Society Congress on September 30, 2025, at 8:44am CEST in Amsterdam, Netherlands Engage with the U.S. FDA to determine the path forward for efzofitimod in pulmonary sarcoidosis

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![Slide 10](atyr-ex99_1s10.jpg)

KOL Commentary Robert P. Baughman, M.D. Emeritus Professor of Medicine, University of Cincinnati Editor, Sarcoidosis, Vasculitis, and Diffuse Lung Disease Editor, Current Opinion in Pulmonary Medicine Past President, World Association of Sarcoidosis and Other Granulomatous Disorders (WASOG) Member, Trial Steering Committee for the EFZO-FIT™ study

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![Slide 11](atyr-ex99_1s11.jpg)

Q&A