At the end of September, Sarepta Therapeutics (“Sarepta”) announced positive data from a study exploring SRP-9003, a gene therapy candidate, as a potential treatment for patients with limb-girdle muscular dystrophy type 2E (LGMD2E). As there are no current approved treatments for LGMD2E, SRP-9003 presents a very promising option. Researchers followed patients from three clinical trials over an 18-month (1.5 year) period. During this time, they noted positive and sustained responses.

SRP-9003

Developed by Sarepta, SRP-9003 is a gene therapy delivered to the skeletal and cardiac muscles via an AAVrh74 vector. As LGMD2E often causes cardiac or pulmonary issues, this method of delivery is more effective than other solutions. Within the study evaluating the efficacy of SRP-9003 in pediatric patients with LGMD2E, patients received one intravenously administered injection. Patients were split into two cohorts depending on their weight. Participants in the study were between the ages of 4 and 15.

Following SRP-9003 treatments, patients saw low creatine kinase levels, higher beta-sarcoglycan protein levels, and increased movement and motor function.

Limb-Girdle Muscular Dystrophy Type 2E (LGMD2E)

Limb-girdle muscular dystrophy, as a whole, falls under the greater umbrella of muscular dystrophy. An estimated 1 in 14,500-123,000 people have limb-girdle muscular dystrophy. However, there are multiple forms of the condition dependent on specific genetic mutations: LGMD2A, LGMD2B, LGMD2C, etc. In the case of LGMD2E, SGCB genes are responsible for inheriting the condition.

Generally, LGMD is characterized by progressive muscle weakness and muscle atrophy, particularly in the thighs, pelvis, arms, and shoulders. In LGMD2E, patients experience symptoms such as:

• Progressive muscle weakness
• Difficulty running, walking, jumping, or climbing stairs
• Abnormal gait
• Scoliosis
• Calf muscle contractures
• Pulmonary or cardiac weakness
• Intellectual and developmental delays

In many cases, patients with LGMD2E lose the ability to walk by the time they are teenagers. Additionally, this condition is often fatal early-on.

Learn more about LGMD here.