Rett syndrome: The Natural History Study journey

Area of Science:

• Neurology
• Rare Diseases
• Clinical Research

Background:

• The Rett syndrome Natural History Study (NHS) was established to understand clinical features and disease progression.
• Legislative acts, including the Orphan Drug Act (1983) and Rare Diseases Act (2002), facilitated rare disease research and funding.
• Funding in 2003 enabled a network of investigators to study Rett syndrome (RTT) and related disorders, such as CDKL5 deficiency disorder, FOXG1 disorder, and MECP2 duplication syndrome.

Purpose of the Study:

• To enhance understanding of Rett syndrome (RTT) clinical features and disease progression.
• To establish clinical trial readiness for RTT and related rare neurological disorders.
• To identify potential biomarkers and clinical outcome measures for rare diseases.

Main Methods:

• Longitudinal data collection from over 1800 participants, with more than 1600 diagnosed with RTT.
• Establishment of a broad network of clinical investigators across the United States.
• Retrospective analysis of natural history study conduct for rare disorders.

Main Results:

• Detailed descriptions of clinical features and natural progression for RTT and related disorders.
• Identification of putative biomarkers and clinical outcome measures.
• Facilitation of the evaluation of the first FDA-approved medication for RTT in 2023.

Conclusions:

• The RTT NHS significantly contributed to clinical trial readiness and therapeutic development for rare neurological disorders.
• The study provides valuable guidance for conducting future natural history studies in rare diseases.
• Collaborative efforts in rare disease research are crucial for improving the lives of affected individuals and families.