The use of CPPs to improve PMO delivery is one such approach and was first demonstrated with arginine-rich B-peptide (B-PMO) that demonstrated approximately 50% wild-type dystrophin levels following a single 25 mg/kg dose [9] concurrent with partial restoration in cardiac function measures following dobutamine-mediated stress induction, and improved muscle function [10] following intravenous systemic administration into the mdx mouse model of DMD. Here, DMD is linked to Duchenne muscular dystrophy.