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  4. Grant Programs to Support Development of Medical Products for Rare Diseases
  5. FDA Rare Neurodegenerative Disease Grants Program
  6. FDA Operational Definition of a Rare Neurodegenerative Disease
  1. FDA Rare Neurodegenerative Disease Grants Program

FDA Operational Definition of a Rare Neurodegenerative Disease

For organizations interested in applying for funding under the FDA Rare Neurodegenerative Disease Grants Program

On this page: Statutory definition of RND | Conditions that are not eligible | Contact us

The FDA Rare Neurodegenerative Disease Grants Program is administered by the FDA Office of Orphan Products Development (OOPD). This page provides information about eligibility for this program. 

Rare neurodegenerative disease (RNDD) definition

Neurodegenerative diseases occur when nerve cells in the brain or peripheral nervous system lose function over time and ultimately die. In general, they are incurable and debilitating conditions and are progressive. The term rare disease or condition is defined in 21 U.S.C. 360ee.

Primary progressive neuronal degeneration: To be eligible for the RND grants program, neuronal loss in the central or peripheral nervous system must occur and must be progressive. The applicant needs to provide enough information for FDA to determine that the proposed disease or condition meets this definition of a neurodegenerative disease. If a rare disease does not meet the criteria for a neurodegenerative disease, please see below for Orphan Products Grants Program funding mechanisms which are available to all rare diseases.

Conditions that are not eligible for the RNDD grants program

Primary muscle disorders are excluded: 

Duchenne and Becker Muscular Dystrophy (DMD/BMD) are degenerative muscle diseases (primary muscle disorder), but do not to fulfill the definition of “neurodegenerative” disease based on neuronal degeneration. For the same reason, Inclusion Body Myositis is not eligible as it is a progressive primary muscle disorder. 

Diseases with secondary neuronal loss are excluded: 

Brain tumors, such as glioma, are primarily oncologic diseases. Neuronal degeneration and loss in function is secondary to progression of the tumor.

Diseases with initial acute neuronal loss but without progression are excluded: 

Spinal cord injury causes acute neuronal injury and degeneration, but it is not progressive. Another example would be is vascular stroke (ischemic or hemorrhagic) in which there is acute neuronal loss but is not progressive.

Neurodevelopmental disorders:

The applicant needs to provide enough information for FDA to justify that there is a neurodegenerative component, not just solely a neurodevelopmental disease.   

  • Several neurodevelopmental diseases are static in nature, i.e., non-progressive, and therefore do not fulfil the definition of a neurodegenerative disease. Examples of this would be autism spectrum disorders which are neurodevelopmental and are non-progressive.
  • In some neurodevelopmental diseases, there may be evidence suggestive of progressive neuronal loss in a small subset of patients affected by the disease (less than 50%). Such neurodevelopmental conditions are not eligible for neurodegenerative grant applications.
  • In other neurodevelopmental diseases, where there may be evidence suggestive of progressive neuronal loss in the majority of patients affected by the disease (50% or more). Such neurodevelopmental conditions are eligible for neurodegenerative grant applications.

Questions on if you qualify for the Rare Neurodegenerative Disease Grants Program?

Contact OOPD if you have questions on whether a disease is a rare neurodegenerative disease. Such determination will be based on information provided by the applicant in the letter of intent/grant application or in response to request for additional information from OOPD. 

If there is inadequate information, OOPD will contact the applicant for additional information from current literature specific to assess whether the subject disease is neurodegenerative. Information received will need to be adequate for FDA to determine whether a given disease or condition is neurodegenerative.  For those diseases that do not qualify as a rare neurodegenerative disease at this time or do not have enough information to justify, OOPD will encourage them to consider the Orphan Products Grants Program funding mechanisms, which are available to all rare diseases. 

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