Low prevalence, lack of knowledge about the disease course, and phenotype heterogeneity hamper the development of drugs for rare diseases. Rare disease registries can be helpful by playing a role in understanding the course of the disease, and providing information necessary for clinical trial design, if designed and maintained properly. We describe the potential applications of a rare disease and what type of information should be incorporated to support the design of clinical trials in the process of drug development supported a broad inventory of written record expertise. We evaluated two existing Rare disease in more detail to check the completeness of these Rare disease for trial design. Before and during the application for regulatory approval rare diseases can improve the efficiency and quality in clinical trial design by informing the sample size calculation and expected disease course. In exceptional circumstances information from rare diseases has been used as historical controls for a one-armed clinical trial, and high quality rare diseases may be used for registry-based randomized controlled trials. In the post marketing phase of (conditional) drug approval disease-specific rare diseases is likely to provide more relevant information than a product-specific registry.A rare disease registries can be very helpful to improve the efficiency and quality of clinical trial design in several ways. To alter the pertinence and optimum use of rare un-wellness longitudinal information assortment is indispensable, and specific data collection, prepared for repeated measurement, is needed. The developed listing will facilitate to outline the suitable variables to incorporate. Attention should be paid to the inclusion of patient-relevant outcome measures in the rare diseases from the start. More research and experience is needed on the possibilities and limitations of combining rare diseases information with clinical trial data to maximize the availability of relevant evidence for regulatory decisions in rare diseases.
Keywords: Development, Impact, new drug treatments, rare disease
