aTyr Pharma Inc.

On September 15, 2025, aTyr announced that the Phase 3 study of its intravenous Efzofitimod pulmonary sarcoidosis treatment, EFZO-FIT, did not meet its primary endpoint in change from baseline in mean daily OSC dose at week 48.

On this news, aTyr’s stock price fell $5.01, or 83.2%, to close at $1.02 per share on September 15, 2025, thereby injuring investors.

The complaint filed in this class action alleges that throughout the Class Period, Defendants made materially false and/or misleading statements, as well as failed to disclose material adverse facts about the Company’s business, operations, and prospects. Specifically, Defendants failed to disclose to investors that: (1) Defendants created adverse facts concerning aTyr’s study design for EFZO-FIT, giving the false impression that Efzofitimod would meet its primary endpoint; (2) Defendants crafted a narrative that the Phase 3 EFZO-FIT study would provide a way for patients to fully remove steroids from their treatment plans; (3) there may be other factors that permit patients to completely remove steroids from their treatment plans; (4) thus, their Phase 3 EFZOFIT study failed to meet the primary endpoint in change from baseline in mean daily OCS dose at week 48; and (5)as a result, Defendants’ positive statements about the Company’s business, operations, and prospects were materially misleading and/or lacked a reasonable basis at all relevant times.