...rame deletions. Modulation of pre-mRNA splicing by exon skipping is the most promising molecular intervention in DMD. 2 Phase Ib and 2 Phase IIa clinical trials (MDEX Consortium in collaboration with Sarepta Therapeutics; a Dutch Consortium) demonstrated that delivery of antisense oligonucleotides (AOs) to mediate exon skipping of exon 51 were able to return specific DMD mutations in-frame (~13% o ...