DMD and Duchenne muscular dystrophy: In DMD patients, two chemistries targeting dystrophin exon 51, drisapersen, a 2’-O-methyl-phosphorothioate (2OMePS), and eteplirsen, based on phosphoramidate morpholino (PMO), both elicited the expected exon 51 skipping and local dystrophin restoration following intramuscular injection [2, 3].