Washington, D.C. 20549



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

Date of Report (Date of earliest event reported): September 10, 2023



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Item 8.01 Other Events.

On September 10, 2023, aTyr Pharma, Inc. presented the results of a post-hoc analysis of data from its Phase 1b/2a study of efzofitimod in patients with pulmonary sarcoidosis in a poster at the European Respiratory Society International Congress 2023.

The poster presents findings from a pooled, post-hoc analysis of data from a Phase 1b/2a randomized, double-blind, placebo-controlled, multiple ascending dose (1.0, 3.0 and 5.0 mg/kg) 24-week study of efzofitimod in patients with pulmonary sarcoidosis receiving oral corticosteroid (OCS) dose ≥ 10.0 mg/day. Patients were randomized 1:2 (placebo:efzofitimod) and underwent a forced steroid taper in the first 8 weeks of the study. Dose dependent improvements in steroid burden, forced vital capacity (FVC) and patient reported outcomes (PRO) were noted, though the study was not powered for efficacy.

In this pooled analysis, the 3.0 mg/kg (N=8) and 5.0 mg/kg (N=9) efzofitimod arms were considered therapeutic, and pooled. The placebo (N=12) and 1.0 mg/kg (N=8) efzofitimod arm, which was considered subtherapeutic, were pooled. Time to relapse for steroid use (defined as dose of OCS increased after OCS taper to 5.0 mg or less of prednisone or equivalent for at least five consecutive days), rate of change for FVC and proportion of patients with changes that are multiples of the minimally clinically important difference (MCID) in PRO (Kings Sarcoidosis Questionnaire-Lung, or KSQ-L) were compared. Additionally, a responder endpoint was proposed (defined as reduction in OCS from baseline without worsening in FVC or PRO) and an analysis was performed. Key findings include:

7.7% of patients in the therapeutic group relapsed for steroid use compared to 54.4% of patients in the placebo/subtherapeutic group (p=0.017);
The rate of change for FVC was significantly improved for the therapeutic group compared to the placebo/subtherapeutic group (p =0.035);
52.9% of patients in the therapeutic group showed an increase ≥12 for KSQ-L (3 times MCID) compared with 15.0% in the placebo/subtherapeutic group (p=0.032); and
64.7% of patients in the therapeutic group achieved response compared to 20.0% in the placebo/subtherapeutic group (p=0.008).








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.



/s/ Jill M. Broadfoot

Jill M. Broadfoot

Chief Financial Officer


Date: September 11, 2023