FDA Grants Orphan Drug Designation to Efzofitimod for Systemic Sclerosis

The US Food and Drug Administration (FDA) has granted orphan drug designation for aTyr Pharma’s immunomodulator efzofitimod for treatment of systemic sclerosis (SSc).

Proof-of-concept comes from a Phase 1b/2a study of efzofitimod for the treatment of patients with pulmonary sarcoidosis, the lead indication for this drug. Many patients with SSc develop associated interstitial lung disease (ILD), whose pathology is driven by the same immune cells central to sarcoidosis pathology. This study demonstrated safety and consistent dose response. Trends of that study also indicate that efzofitimod had better outcomes than placebo on the key endpoints of steroid reduction, lung function, clinical symptoms, and inflammatory biomarkers.

Efzofitimod was also found to reduce lung and skin fibrosis in animal models of SSc and idiopathic pulmonary fibrosis. In that study, efzofitimod outperformed existing antifibrotic agents such as nintedanib and pirfenidone.

SSc affects approximately 100,000 people in the US, with 55%-65% going on to develop associated ILD (also called SSc-ILD). If SSc-ILD is left untreated, it can cause scarring, leading to permanent loss of lung function. Currently, ILD is the primary cause of death for patients with SSc.

—Allison Casey

Reference:
aTyr Pharma announces FDA orphan drug designation for efzofitimod (ATYR1923) for treatment of systemic sclerosis. News Release. aTyr Pharma, Inc. April 13, 2002.