Abstract
<jats:p>Duchenne muscular dystrophy is a lethal neuromuscular disorder caused by the absence of dystrophin, for which no curative treatment is available. RNA based approaches have shown promising results; however, their evaluation is hindered by the lack of robust and rapid delivery methods for differentiated human muscle cells, which represent the most physiologically relevant in vitro models for assessing therapeutic strategies. Here, we establish a versatile lipid nanoparticle platform enabling efficient delivery of diverse RNA therapeutics across a range of human muscle models, including myotubes, induced pluripotent stem cell-derived myotubes, myoblasts, cardiomyocytes, and 3D engineered skeletal muscle tissues. Remarkably, a single commercially available lipid nanoparticle formulation supports delivery of cargos spanning more than 300-fold in size, from short antisense oligonucleotides (~20 nt) to complex CRISPR-based editors (up to ~6.7 kb), including Cas9 nucleases, adenine base editors, and CRISPRa systems. This enables efficient gene correction and transcriptional modulation, resulting in dystrophin restoration or compensatory utrophin upregulation in relevant Duchenne muscular dystrophy models. Together, our results establish a single lipid nanoparticle formulation as a versatile platform for RNA delivery in human muscle systems and provide a practical framework for the rapid preclinical assessment of emerging therapies for Duchenne muscular dystrophy and other neuromuscular disorders.</jats:p>