SOUTH SAN FRANCISCO, Calif. — Epicrispr Biotechnologies has dosed the first patient in its global first-in-human clinical trial of EPI-321, the first investigational therapy designed to silence DUX4 expression through epigenetic modulation for facioscapulohumeral muscular dystrophy (FSHD).
FSHD is a rare genetic disorder affecting about 1 in 8,000 people worldwide, causing progressive skeletal muscle degeneration and severe loss of function. There are currently no approved disease-modifying treatments for the condition.
“For too long, individuals with FSHD have endured this progressive disease with no treatment options,” said Amber Salzman, Ph.D., Epicrispr’s CEO. “EPI-321 represents the start of a new chapter where we’re finally evaluating a therapy that targets the underlying cause.”
Mark Stone, CEO of the FSHD Society, called the milestone “a turning point” for patients and families, praising Epicrispr for advancing a therapy that could address the disease at its root.
EPI-321 is delivered intravenously via an adeno-associated virus (AAV) vector and aims to silence aberrant DUX4 gene activity in skeletal muscle. Preclinical studies have shown strong suppression of DUX4 expression and protection of muscle tissue. The therapy has received U.S. FDA Fast Track, Rare Pediatric Disease, and Orphan Drug designations.
The trial will assess the therapy’s safety, tolerability, and pharmacodynamics in adults with genetically confirmed FSHD. Initial results are expected in early 2026.
