The present invention relates to the delivery of oligomers for treating patients with a 5′ mutation in their DMD gene other than a DMD exon 2 duplication. The invention provides methods and materials for activating an internal ribosome entry site in exon 5 of the DMD gene resulting in translation of a functional truncated isoform of dystrophin. The methods and materials can be used for the treatment of muscular dystrophies arising from 5′ mutations in the DMD gene such as Duchenne Muscular Dystrophy or Becker Muscular Dystrophy.