Topics Potential Impact of IRUD Reconfirmed by National-Scale Field Survey


The Japan Agency for Medical Research and Development (AMED) announces that over 37,000 undiagnosed patients could benefit from one of its flagship programs, called the Initiative on Rare and Undiagnosed Diseases (IRUD). The numbers were estimated by a nationwide field survey in collaboration with family clinics, general hospitals, and national and private university hospitals.

The IRUD, launched by AMED in 2015, continues to help patients with unidentified conditions. It is a national initiative involving multidisciplinary diagnosis committees and phenotype-driven genetic analyses utilizing next-generation sequencing. Over the course of its progress arose a growing need for more information for evidence-based implementation and policy-making, such as the actual number of undiagnosed patients. However, due to difficulties navigating disintegrated data, no systematic studies had been carried out to quantitate such numbers.

To address these difficulties, AMED carried out a nationwide cross-sectional study to ascertain the number of patients with undiagnosed diseases in collaboration with the Japan Medical Association, the Standing Committee of the National University Hospital Council of Japan and the Japanese Association of Private Medical Schools. The survey results suggested that a potential of more than 37,000 undiagnosed patients could exist, despite the very low prevalence of rare diseases.

The numbers solidify the demand and value of the IRUD initiative. As AMED pursues its mission to fast-track medical research and development in all areas including rare and intractable diseases, it is hoped that initiative continues to expand while also serving as a valuable reference for other countries and regions who also share a vision for implementing data in healthcare to better the lives of patients.

Further information can be found in an article published in Orphanet Journal of Rare Diseases:



Division Name Division of Rare/Intractable Disease Research, Department of Research Promotion, AMED
E-Mail irud "at"
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Last updated 12/10/18