DMPK and myotonic dystrophy type 1: Similarly, studies in myotonic dystrophy type 1 (DM1) have shown some efficacy for gapmer AONs to induce the degradation of mutant DMPK transcripts [66,67], however after only small insignificant changes were observed in a phase I/IIa clinical trial by Ionis Pharmaceuticals on ISIS-DMPKRx, this work was halted in favour of exploring further improved next-generation AON chemistries for DM1 treatment.