This study aims to characterize swallowing function in AO NPC1, addressing the gap in understanding and clinical management.<h4>Methods</h4>Fourteen AO NPC1 individuals in a prospective natural history study (NCT00344331) underwent comprehensive assessments, including history and physical examinations utilizing the NPC1 severity rating scale, videofluoroscopic swallowing studies with summary interpretive analysis, and cerebrospinal fluid (CSF) collection for biomarker evaluation at baseline visit. The gene discussed is NPC1; the disease is Niemann-Pick disease, type C1.