Sarepta Therapeutics, Inc. announced that screening is underway in Study SRP-9003-301. Also known as EMERGENE, Study 9003-301 is a Phase 3, multi-national, open-label study of SRP-9003 (bidridistrogene xeboparvovec) for the treatment of limb-girdle muscular dystrophy Type 2E (LGMD2E/R4), or beta sarcoglycanopathy. EMERGENE will enroll 15 participants (ambulatory and non-ambulatory), aged 4 and older, and uses commercially representative process SRP-9003 material.

SRP-9003 (bidridistrogene xeboparvovec) is an investigational gene therapy that uses the AAVrh74 vector, which is designed to be systemically and robustly delivered to skeletal, diaphragm and cardiac muscle, making it an ideal candidate to treat neuromuscular diseases. SRP-9003 is intended to deliver a full-length beta-sarcoglycan transgene and uses the MHCK7 promoter, chosen for its ability to robustly express in the heart, which is critically important for patients with limb-girdle muscular dystrophy Type 2E (LGMD2E), also known as beta-sarcoglycanopathy and LGMDR4, many of whom die from pulmonary or cardiac complications. EMERGENE, Study 9003-301 is a Phase 3, multinational, open-label study of SRP-9003 for the treatment of LGMD2E in 15 ambulatory and non-ambulatory participants, ages 4 and older.

The EMERGENE design incorporates a six-month natural history lead-in. The primary endpoint is expression of beta-sarcoglycan 60 days after dosing. Other endpoints include functional measures through month 60 and safety.

Limb-girdle muscular dystrophies are genetic diseases that cause progressive, debilitating weakness and wasting that begins in muscles around the hips and shoulders before progressing to muscles in the arms and legs. Sarepta?s six LGMD gene therapy programs in development include LGMD2E/R4, LGMD2D, LGMD2C, LGMD2B, LGMD2L and LGMD2A, which together represent more than 70% of known LGMD cases. Patients with LGMD2E (beta-sarcoglycanopathy) begin showing neuromuscular symptoms such as difficulty running, jumping and climbing stairs before age 10.

The disease, which is an autosomal recessive subtype of LGMD, progresses to loss of ambulation in the teen years and often leads to early mortality. There are currently no disease modifying treatments for LGMD2E.