DMD and Duchenne muscular dystrophy: NCT04240314, officially titled “Phase I/IIa Systemic Gene Delivery Clinical Trial of scAAV9.U7.ACCA for Exon 2 Duplication-Associated Duchenne Muscular Dystrophy”, is an open-label study primarily designed to assess the safety of scAAV9.U7.ACCA in DMD patients with a confirmed DMD exon-2 duplication.