Major Investor Concerns Arise After aTyr Pharma's Share Price Plummets Due to Study Failure

aTyr Pharma's EFZO-FITÔ Study Failure: Investor Reactions and Investigations

On September 15, 2025, aTyr Pharma, Inc. (NASDAQ: ATYR) experienced a catastrophic drop in share prices, with values plummeting more than 80% following disappointing results from its late-stage study of efzofitimod. This medication was intended to treat pulmonary sarcoidosis, a serious interstitial lung disease (ILD). The market's reaction was swift and severe, leading to increased scrutiny from investors and legal firms alike.

The fallout began when aTyr announced during their EFZO-FITÔ topline results call that the primary endpoint of their trial — which aimed for a reduction in steroid use after a year of tapering — was not achieved. The company revealed that the results showed lower statistical significance, with the placebo group performing unexpectedly well, even surpassing the company's more optimistic model predictions. This disclosure was a harsh reality check for investors who were counting on positive outcomes based on aTyr's previous claims of successful Phase 2 data.

Hagens Berman, a national law firm representing shareholders, quickly stepped in, starting an investigation to determine whether aTyr misled investors regarding its trial design and data integrity. The firm expressed concerns over statements made by aTyr, including claims that their Phase 2 data represented