An Overview of Therapies for Duchenne Muscular Dystrophy

Duchenne Muscular Dystrophy has been extensively researched due to its severity and ability to cause an early death. Therefore, many researchers and companies, including Sarepta Therapeutics and others, have sought to develop therapies for the disorder.  This post offers a brief overview of the disorder itself and therapies for DMD.  A case study will then be performed, in a later post, on Sarepta Therapeutics' efforts to get a drug therapy for DMD to market.

DMD is characterized by the absence of functional dystrophin protein in muscle cells, resulting in severe weakening and degeneration of muscle tissue (“Overview Duchenne Muscular Dystrophy” 2015). The neuromuscular disorder is diagnosed in 1 out of 3500 males and people with DMD start experiencing muscle weakness as early as 3 years old (“Signs and Symptoms Duchenne Muscular Dystrophy” 2015). After reaching age 10, DMD causes the muscle layer within the heart and the diaphragm begin to weaken, which increases the risk of the patient dying due to cardiac or respiratory failure prior to age 30.

There are several different therapeutic approaches to treating DMD. In 2015, Santhera Pharmaceuticals were approved for the FDA’s Fast Track program in the treatment of Duchenne muscular dystrophy, DMD, using the drug Raxone®/Catena® (“Santhera receives FDA Fast Track” 2015). This Fast Track program serves to enhance the ability for drugs that treat serious medical conditions, like DMD, to come to the market. The novel therapeutic produced by Santhera provides an alternative to other pre-existing therapies for DMD, which include cell/gene therapies, corticosteroids, and regenerative medicine (Leung and Wagner 2013). Other pharmaceuticals are being developed such as the VBP15 made by ReveraGen BioPharma (“Lead Program: VBP15”). A drug or cell therapy must be used to supplement clinical management of symptoms and complications (Guglieri and Bushby 2010) arising from DMD. Clinical management of DMD tends to involve physical therapy and corrective exercises that aid the leg muscles. Deflazacort, a corticosteroid often prescribed for DMD, is one drug therapy for the disorder (Campbell and Jacob 2003). Genetic engineering can also be performed: correcting the genetic reading frame of the dystrophin gene with synthetic nucleases is capable of producing functional albeit shortened dystrophin protein (Ousterout et. al 2013).  Each potential therapy has its strengths and weaknesses though regenerative medicine and tissue engineering approaches require more work. 

Understanding the therapies available provides insight into how Sarepta Therapeutics' drug fits into the market. Therefore, this therapy can be seen as separate from the alternatives. A case study will be written on the efforts of this company to bring the drug to market with an emphasis on their collaboration with the FDA.

Works Consulted

Campbell, Craig and Pierre Jacob. “Deflazacort for the treatment of Duchenne Dystrophy: A systematic review.”  BMC Neurology 3.7 (2003). Print.
Guglieri, Michela and Kate Bushby. “Molecular Treatments in Duchenne muscular dystrophy.” Current Opinion in Pharmacology 10 (2010): 331-337. Print.

Leung, Doris G., and Kathryn R. Wagner. “Therapeutic Advances in Muscular Dystrophy.” Ann Neurol 74 (2013): 404-411. Print.

Ousterout, David G., Pablo Perez-Pinera, Pratiksha I. Thakore, Ami M. Kabadi, Matthew T. Brown, Xiaoxia Qin, Olivier Fedrigo, Vincent Mouly, Jacques P. Tremblay, and Charles A. Gersbach. “Reading Frame Correction by Targeted Genome Editing Restores Dystrophy Expression in Cells From Duchenne Muscular Dystrophy.” Molecular Therapy 21.9 (2013): 1718-1726. Print.

“Lead Program: VBP15.” ReveraGen BioPharma (2015). Web. 28 June 2015.

“Overview Duchenne Muscular Dystrophy.” Muscular Dystrophy Association (2015). Web. 14 Apr. 2015.

“Santhera receives FDA Fast Track Designation for Raxone®/Catena® (idebenone) for the Treatment of Duchenne Muscular Dystrophy (DMD)” Santhera Pharmaceuticals (2015). Web. 14 Apr. 2015.

“Signs and Symptoms Duchenne Muscular Dystrophy.” Muscular Dystrophy Association (2015). Web 14 Apr. 2015.

Blogging and Health Policy

Hello, everyone. I want to inaugurate this new blog, Becker's and Beyond - I intend to write about health policy covering a plethora of topics. The title means, on a superficial level, that the topics covered will range from Becker's Muscular Dystrophy to other topics such as FDA regulation of drugs per the Center for Drug Evaluation and Research (CDER). On a more philosophical level, the title refers to the fact that treatments for Duchenne Muscular Dystrophy, which is essentially a more severe version of Becker's, transform the mutation of DMD into the mutation of BMD. Therefore, treatments for BMD, especially those that use cell and gene therapies, are harder to develop. In a nutshell, the purpose of this blog is to discuss challenging areas in health policy and the development of biomedical technology. I intend to merge my knowledge of health policy and my knowledge of therapeutic strategies. My older sister will also be a contributor to this blog.

For the first post, I will describe the state of FDA regulation for drugs that aim to treat Duchenne. Because many such drugs are currently being manufactured, I will focus on Sarepta Therapeutics' drug therapy for DMD.