Danon Disease Natural History Study

This is an international observational study with both retrospective and prospective data collection. The study is designed to describe the natural history of Danon disease, a rare X-linked genetic disorder, and one of the most severe and penetrant forms of inherited cardiomyopathy. This study will collect data about the clinical course of Danon disease, including signs and symptoms, key clinical events, and the impact of the disease on quality of life as managed with the current standard of care. A hybrid (retrospective and prospective data collection) approach is being used to generate robust and longitudinal data. A subset of patients will be used as an External Control Arm for comparison to RP-A501 Trial participants.