Awareness Initiatives and Innovative Therapeutic Approaches Bring Hope to People Living with Becker Muscular Dystrophy

The following content is sponsored by Edgewise Therapeutics and does not reflect the views of Muscular Dystrophy News or Bionews, Inc.

Becker muscular dystrophy (Becker) is a serious genetic disease that imposes significant physical, emotional, financial, and social challenges on affected individuals and their families. Symptoms of Becker, including muscle wasting and cardiopulmonary deficits, can appear at any time of life, and functional decline continues once it begins.^1,2 Currently there are no approved therapeutic interventions specifically for Becker.

Recent efforts aimed at building an active and united Becker community have brought new energy and new hope to those living with the disorder, as well as their caregivers and care providers. Additionally, several clinical trials are underway, including an innovative muscle-targeted intervention by Edgewise Therapeutics that was recently granted Fast Track Designation by the US Food and Drug Administration.³ Learn more about the Grand Canyon Study and other news from Edgewise here.

In Becker, Muscle Contraction Causes Injury

Muscles are made up of bundles of muscle fibers that contain two key proteins, myosin and actin, which work together to make muscles contract and produce movement. Muscle fibers also contain protective components, such as the protein dystrophin, which helps link muscle fibers together and provides stability and support during contraction. In individuals with Becker, dystrophin function is compromised due to mutations in the dystrophin gene.⁴ Without the full support provided by dystrophin, muscle fibers are still able to contract but the chance of injury is much greater, and the muscle’s ability to repair itself is diminished. Over time, damaged muscle is replaced by fat and fibrotic scar tissue, leading to loss of function.⁵

Certain muscle fibers, called fast type 2 fibers, are more susceptible to contraction-induced damage⁶. Evidence of this can be found in changes to two muscle-injury-specific indicators, or biomarkers, found in blood. One of the biomarkers, called creatine kinase, leaks out of muscle and into the blood with any kind of muscle injury. The other biomarker, called fast skeletal muscle troponin I (TNNI2), is specifically associated with fast type 2 muscle fibers. High blood levels of TNNI2 in individuals with Becker show that fast muscle fibers are incurring significant injury. Edgewise believes that modulating how fast fibers contract will prevent damage.⁷

What’s Next for Becker

For too long, the global Becker community has been challenged by limited awareness, a scarcity of disease-specific resources, few in-person and online networking opportunities, and misperceptions about disease severity. But recent new initiatives are helping to change things, including a highly successful Becker Educational and Engagement Day (BEED) held in the U.S. late last year. A Becker “masterclass” was also held in Barcelona, Spain, in December of 2023, and sessions provided the most up-to-date information on diagnosis, standards of care, and emerging therapies to health care practitioners.

Additionally, Edgewise Therapeutics, the industry leader in providing support and resources for those living with Becker, worked in collaboration with the Becker community to develop a new disease-specific education website. Please visit www.beckermusculardystrophy.com and also check out the educational videos from the recent Becker Education and Engagement Day.

Beckermusculardystrophy.com was created to provide relevant information and resources to people living with or affected by Becker. EDG-5506 is an investigational therapy that is currently not approved in any territory.

References:

1. Darras, B. T., Program, N., Miller, D. T. & Urion, D. K. Dystrophinopathies – GeneReviews – NCBI Bookshelf. GeneReviews, Seattle (2022).
2. Aartsma-Rus A, Van Deutekom JC, Fokkema IF, Van Ommen GJ, Den Dunnen JT. Entries in the Leiden Duchenne muscular dystrophy mutation database: an overview of mutation types and paradoxical cases that confirm the reading-frame rule. Muscle Nerve. 2006 Aug;34(2):135-44. doi: 10.1002/mus.20586. PMID: 16770791.
3. Edgewise Therapeutics. Edgewise Receives U.S. FDA Fast Track Designation for EDG-5506 for the Treatment of Individuals with Becker Muscular Dystrophy (BMD). Published August 16, 2021. https://investors.edgewisetx.com/news/news-details/2021/Edgewise-Receives-U.S.-FDA-Fast-Track-Designation-for-EDG-5506-for-the-Treatment-of-Individuals-with-Becker-Muscular-Dystrophy-BMD-2021-8-16/default.aspx
4. Muscular Dystrophy Association. Becker Muscular Dystrophy (BMD). https://www.mda.org/disease/becker-muscular-dystrophy. Accessed April 1, 2024.
5. Kinali M, et al. Muscle histology vs. MRI in Duchenne muscular dystrophy. Neurology. 2011;76(4):346-53.
6. Moens P, et al. Increased susceptibility of EDGL muscles from mdx mice to damage induced by contractions with stretch. J Muscle Res. Cell Motil. 1993;14(4):446-451.
7. Russell AJ, et al. Modulating fast skeletal muscle contraction protects skeletal muscle in animal models of Duchenne muscular dystrophy. J Clin Invest. 2023;133(10):e153837.