Ractigen Therapeutics, a clinical-stage pharmaceutical company dedicated to developing innovative therapies, announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) to RAG-21, its novel siRNA therapy targeting the FUS gene, for the treatment of amyotrophic lateral sclerosis (ALS).

RAG-21 is an siRNA therapy specifically designed to target FUS-ALS, one of the most aggressive subtype of ALS. By leveraging RNA interference (RNAi), RAG-21 safely and effectively reduces FUS protein levels, addressing the root cause of motor neuron degeneration in FUS-ALS. Preclinical studies have demonstrated its potent efficacy and safety, mitigating FUS cytoplasmic mis-localization and aggregation. As a novel RNA-based therapy, RAG-21 offers renewed hope for improving outcomes in patients suffering from this challenging form of ALS, which currently lacks effective treatment options. This designation marks our second FDA ODD for treating ALS, following RAG-17 for SOD1-ALS, reflecting our commitment to conquering ALS.

Orphan drug designation is granted by the FDA to a drug intended to treat a rare disease or condition, which generally affects fewer than 200,000 individuals in the United States. The designation provides companies with incentives including a 25% tax credit on qualified clinical trials, a seven-year marketing exclusivity and a waiver of the New Drug Application fee.

"The FDA's Orphan Drug Designation for RAG-21 underscores the critical need for innovative therapies targeting ALS, particularly for patients with FUS mutations," said Dr. Long-Cheng Li, Founder and CEO of Ractigen Therapeutics. "FUS-ALS represents one of the most severe and rapidly progressing subtypes of ALS, with no curative treatments currently available. We are committed to developing innovative therapies like RAG-21 to provide meaningful treatment options for patients with ALS and other life-threatening rare diseases."