This study is evaluating the safety and tolerability of a low and high dose exon skipping intravenous intervention in patients with Duchenne muscular dystrophy (DMD). The exon skipping intervention, NS-065/NCNP-01, is targeted for the skipping of exon 53. The study is seeking DMD boys aged 4 to less than 10 years old with a mutation amenable to exon 53 skipping. Approximately 16 patients will be enrolled in sites in the United States. To learn more about the study eligibility and participating sites please visit: https://clinicaltrials.gov/ct2/show/NCT02740972 or contact us at firstname.lastname@example.org.