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MedDRA (Medical Dictionary for Regulatory Activities) 

What is the Medical Dictionary for Regulatory Activities (MedDRA)? 

The Medical Dictionary for Regulatory Activities (MedDRA) is a standardized medical terminology specifically designed for use in regulatory submissions related to human pharmaceuticals and medical devices. It is used for coding, analyzing, and reporting adverse event data from clinical trials, post-marketing surveillance, and other safety reporting activities. 

Developed by the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH), it ensures consistency in the terminology used across different regions and regulatory bodies. It is used by regulatory authorities in the United States (FDA), Europe (EMA), Japan (PMDA), and many other countries.

MedDRA uses a hierarchical structure, organizing terms into five key levels to facilitate precise coding and data analysis:

  • System organ classes (SOCs): The broadest categories (e.g., "Cardiac disorders")
  • High-level group terms (HLGTs): Intermediate groupings (e.g., "Cardiac arrhythmias")
  • High-level terms (HLTs): More specific groupings within HLGTs (e.g., "Atrial fibrillation and flutter")
  • Preferred terms (PTs): Standardized medical terms for individual concepts (e.g., "Atrial fibrillation")
  • Lowest level terms (LLTs): Synonyms, lexical variants, and subtypes of PTs (e.g., "A-fib" for "Atrial fibrillation")

The MedDRA Maintenance and Support Services Organization (MSSO) is responsible for maintaining and distributing MedDRA. The MSSO provides training and user support and ensures the ongoing development and refinement of the dictionary.

Why is MedDRA important for healthcare? 

Overall, MedDRA plays a vital role in streamlining the regulatory process for medical products by ensuring clear and consistent communication of safety data. It ensures consistency and accuracy of medical event reporting, which is crucial for reliable safety assessments. It also provides a common language for regulatory bodies and pharmaceutical companies across the globe and allows for easier comparison and aggregation of safety data from different studies and countries.