INTRODUCTION: Duchenne muscular dystrophy (DMD) causes progressive muscle loss due to dystrophin gene mutations. Exon-skipping therapies correct deletion mutations by restoring the open-reading frame to produce a shortened dystrophin protein containing essential functional domains. Viltolarsen, an FDA-approved therapy for the treatment of DMD in patients with mutations amenable to exon 53 skipping, has been evaluated in several Phase II clinical trials. However, study criteria did not include participants aged <4 years at time of first infusion. Given the absence of age restrictions for viltolarsen, characterizing its real-world use in younger patients may provide critical insights into the clinical and therapeutic implications of earlier intervention. This analysis uses US claims data to evaluate treatment patterns and clinical considerations in children receiving viltolarsen before age 4 years. METHODS: This retrospective cohort study will identify male patients <4 years old at date of first viltolarsen infusion with confirmed DMD diagnosis and anonymized open viltolarsen claims between January 1, 2017, and October 14, 2025, from Veeva Compass Patient (longitudinal anonymous patient-level data). Analysis will include patient demographics, age, port placement rates, corticosteroid usage, and concomitant DMD therapy use. RESULTS: Findings are expected to characterize real-world viltolarsen treatment patterns in children <4 years of age. CONCLUSION: This analysis will provide valuable insights into early initiation of viltolarsen in children <4 years old with DMD. Understanding treatment trends and clinical considerations will help inform future strategies to optimize early treatment of patients with DMD with mutations amenable to exon 53 skipping.