The National Institutes of Health (NIH) through the National Institute of Neurological Disorders and Stroke (NINDS) and the NIH Office of the Director is offering funding to support exploratory and developmental research on Guillain-Barré Syndrome (GBS) and Chronic Inflammatory Demyelinating Polyneuropathy (CIDP). This initiative, titled "Exploratory/Developmental Research on Guillain-Barre Syndrome and Chronic Inflammatory Demyelinating Polyneuropathy (R21)," seeks projects that will advance understanding, prevention, and treatment of these rare autoimmune neuropathies. The Funding Opportunity Announcement (FOA) encourages innovative studies focusing on disease mechanisms, susceptibility factors, biomarkers, and model systems. Applications involving clinical trials are not allowed under this FOA.

Research objectives include investigating immune responses in peripheral nerve damage, identifying genetic risk factors, exploring therapeutic targets, and developing novel treatment strategies. Additional focus areas include the mechanisms of existing treatments like intravenous immunoglobulin (IVIg) and plasmapheresis and identifying predictive biomarkers to optimize these therapies. Studies involving animal models, cellular models, or biospecimens from GBS or CIDP patients are required for responsiveness to the FOA. Research proposals must not focus exclusively on infectious agents related to GBS without a corresponding immunological study component.

The award provides an estimated $3 million for approximately seven grants, each limited to $275,000 in direct costs for a two-year project period. Applications may request up to $200,000 in direct costs for a single year. This FOA supports new and resubmitted R21 applications but excludes renewals. Projects that align with the Office of Autoimmune Disease Research (OADR) interests may also be eligible for additional co-funding. Relevant research should support the goals of the NIH-Wide Strategic Plan for the Health of Women, as OADR is housed within the NIH Office of Research on Women’s Health (ORWH).

Eligible applicants include higher education institutions, for-profit and nonprofit organizations, government entities, tribal governments, and faith-based or community-based organizations. Both domestic and foreign entities are eligible to apply. Registrations with SAM, NCAGE (for foreign entities), eRA Commons, and Grants.gov are required before submission, which may take six weeks or longer to complete. NIH encourages early submission to allow time for correction of errors identified during the application process.

Applications must adhere to NIH’s Research (R) Instructions and include required components such as a Data Management and Sharing Plan. Letters of intent are not mandatory but are encouraged to assist NIH in planning the review process. Specific requirements include comprehensive descriptions in areas such as Resource Sharing Plans and recruitment and retention plans for diverse study populations. Applications that fail to meet these requirements or are non-responsive (such as lacking required model systems or patient data) will be administratively withdrawn without review.

The NIH peer review process will evaluate applications based on scientific merit, innovation, feasibility, and investigator expertise. Key evaluation criteria include the significance of the research, the rigor of the approach, and the appropriateness of the research environment. Applications will undergo a two-tier review, with funding decisions based on scientific merit, funding availability, and program alignment.

Submission deadlines are March 3, 2025, and October 3, 2025. Queries regarding scientific or research-related details should be directed to designated NIH contacts. This FOA is authorized under Sections 301 and 405 of the Public Health Service Act, with awards governed by the NIH Grants Policy Statement and federal regulations.