Earlier this year, the FDA granted Accelerated Approval to ELEVIDYS (delandistrogene moxeparvovec-rokl) for the treatmnt of Duchenne muscular dystrophy (DMD) in boys aged 4-5. While this is a stunning advance and can provide support to numerous families, more work is still needed to identify therapeutic options for those outside of that range, as well as a potential cure. One therapy being explored is SAT-3153. Developed by biotechnology company Satellos Bioscience Inc. (“Satellos”), SAT-3153 is a first-in-class small molecule therapy that inhibits a certain kinase protein. The treatment is orally administered. Satellos chose to inhibit this protein because the company feels that it controls Notch polarity in muscle stem cells. Polarity refers to how the muscle repair and regenerate themselves. Issues in polarity could cause muscle issues; in fact, some researchers believe that DMD could result from problems with muscle polarity that fail to allow tissues to repair themselves.
In a recent news release, Satellos announced that the FDA granted both Orphan Drug and Rare Pediatric Disease designations to SAT-3153. Orphan Drug designation is granted to therapies intended to treat rare conditions, or conditions affecting fewer than 200,000 Americans. This designation comes with incentives such as fee waivers, tax credits, increased regulatory assistance, and 7 years of market exclusivity upon the drug’s approval. Orphan Drug designation began after the Orphan Drug Act to encourage drug development within the rare sphere. Rare Pediatric Disease designation centers specifically on therapies for serious or life-threatening diseases affecting people under 18 years old. It comes with a Priority Review voucher which provides eligibility for priority review in a later marketing application.
What is Duchenne Muscular Dystrophy (DMD)?
Altogether there are nine different types of muscular dystrophy; Duchenne muscular dystrophy (DMD) is one of these forms. This progressive muscle-wasting disease occurs due to a genetic mutation that prevents the creation of dystrophin in muscles. Dystrophin stabilizes and protects muscle fibers. When the body cannot create enough dystrophin in muscles, the muscles weaken. This can lead to life-threatening cardiac and respiratory issues.
DMD is most common in young males; it occurs in 1 in every 3,500 male births and 1 in every 50,000,000 female births. Symptoms often manifest before six years old and may include:
- Frequent tripping or falling
- Muscle weakness that begins in the thighs, legs, and pelvis before progressing elsewhere
- Large calf muscles
- Difficulty standing from a sitting position
- Problems running, walking, or jumping
- Muscle pain and stiffness
- Learning disabilities
Many people with DMD often use mobility assistance, like wheelchairs, by age 12 or early teens. Unfortunately, DMD may also be fatal by the 20s. This is why continued research into potential therapies or cures is needed.