An Observational Study in Subjects to Follow the Progression of Stargardt Disease Type 1 (STGD1) Caused by Bi-Allelic Autosomal Recessive Mutations in the ABCA4 Gene

Comprehensive knowledge of a disease is essential to the design and conduct of well-controlled, interventional clinical trials. Understanding of the disease state is important for identifying the patient population for a clinical trial, study duration, and selection of clinically meaningful endpoints. Observational studies play an important role in the understanding of rare diseases and facilitating effective development of potential therapies. To support clinical research, observational studies can help define the clinical features of a rare disease, rate of progression, pathophysiology, and other important factors. Further, following the course of a disease over time allows investigators to identify demographic variables, genotypic and phenotypic features, and other characteristics that may correlate with disease and outcomes in the absence of treatment. Thus, observational studies are useful in guiding the design of therapeutic studies, including selection of the patient population, trial duration, and the types of outcome measures to evaluate efficacy and safety. Results of a natural history study evaluating the progression of atrophy secondary to Stargardt Disease have been published using retrospective and prospective cohorts of patients (ProgStar, Strauss et al., 2016). In summary, the current study is a prospective observational study of patients with STGD1, the aim of which is to further enhance understanding of disease progression and structural and functional markers that can be used to evaluate the efficacy and safety of therapeutic interventions, especially in light of advancements in imaging technology.