Sarepta Therapeutics, Inc. recently announced a new study to confirm the dosages of their lead drug eteplirsen as a new therapeutic for treating Duchenne muscular dystrophy-affected patients with a baseline 6-minute walk test score.
Duchenne muscular dystrophy (DMD) is a form of muscular dystrophy that is caused by a mutation of the Dystrophin gene, located in the X chromosome. The Dystrophin protein is an essential component of muscle tissue. Its loss or deficiency leads to muscle degeneration, mainly in the muscle of legs and pelvis, but it progresses to other muscles, including the cardiac muscle. The disease mainly affects males who become symptomatic usually in the first six years of their lives.
The new study – 4658-301 (PROMOVI) – will determine eteplirsen’s safety and efficacy when administered for one year to 160 DMD patients enrolled in several centers across the United States. The group of patients is composed of males between 7-16 years old and divided into two groups, according to their genotype – a group where eteplirsen can skip exon 51 and a second control group not responsive to exon 51 skipping. The Eteplirsen therapeutic will be delivered as a single treatment by intravenous injection of 30 mg/kg, once a week. The authors will use both measurements of dystrophin and 6-minute walk test scores as a readout on the therapeutic’s efficacy when compared to the control group.
Eteplirsen was previously demonstrated as a safe and tolerable drug with positive results in restoring dystrophin protein levels in DMD patients. Its mode of action relies on Sarepta’s exon-skipping technology, where Eteplirsen by skiping exon 51 can restore a shorter but functional dystrophin protein.
Edward Kaye, M.D., Sarepta’s Chief Medical Officer commented, “This confirmatory study with eteplirsen in ambulatory patients is an important step in the process of confirming the promising clinical results we achieved in our previous studies 201/202. By evaluating a larger population of boys and examining both functional and biochemical endpoints, we expect to further support the evidence of eteplirsen’s potential benefit to patients.”
Susan Apkon, M.D., Principal Investigator at Seattle Children’s Hospital added, “The commencement of this study is a significant achievement for the DMD community. Eteplirsen shows great potential as an important therapeutic, and I am delighted to be a part of this larger confirmatory study to understand further the impact that eteplirsen may have on families dealing with this terrible disease.”