Pilot Studies of Biological, Behavioral and Social Mechanisms Contributing to HIV Pathogenesis Within the Mission of NIDDK (R21 Clinical Trial Not Allowed)
🏛 National Institutes of Health (HHS-NIH11)
✓ Free, no account · Source: Grants.gov · Last verified Oct 20, 2026
Can you apply?
This grant is for researchers investigating biological, behavioral, and social factors in HIV pathogenesis. Eligible applicants include universities, research hospitals, and nonprofit research institutions with federal 501(c)(3) status. Researchers must have doctoral degrees (PhD, MD, DO, DVM, or equivalent) or relevant research training. Projects must align with NIDDK's mission in HIV/kidney/metabolic disease research. Clinical trials are not permitted under this R21 mechanism.
Not the right fit? Find grants for your organization in 5 questions →
Program description
This Notice of Funding Opportunity (NOFO) invites applications for innovative basic and translational pilot research projects within the mission of the NIDDK that are aligned with NIH HIV/AIDS research priorities. These priorities were most recently outlined by the NIH Office of AIDS Research (OAR) in NOT-20-018, UPDATE: NIH HIV/AIDS Research Priorities and Guidelines for Determining HIV/AIDS Funding, scientific priorities. Potential topics could address multiple overarching priorities. These include elucidation of unique pathophysiological mechanisms contributing to HIV comorbidities, coinfections, and complications (CCCs) affecting organs, tissues, and processes within the mission of the NIDDK. Likewise, interrogations into biological mechanisms underlying HIV reservoirs in NIDDK-relevant tissues are important for developing strategies for long-term viral suppression or eradication. Finally, health-impeding social determinants of health may affect CCCs or viral reservoirs within NIDDK’s mission through multiple pathways.
Who can apply
Eligible applicants
- 501(c)(3) Public Charity
- City / Municipal Government
- County Government
- Nonprofits
- Private University
- Public Authority
- Public K-12 School
- Public University
- Small Business (SBA-defined)
- Special District
- State Government
- Tribal Nation
- Tribal Organization
Demographic focus
How to apply
Application links
Required documents
- SF-424 (R&R) form
- Project Narrative (Research Strategy section)
- Preliminary Studies/Progress Report
- Budget and Budget Justification
- Biosketches of Key Personnel
- Letters of Support (if applicable)
- Facilities and Resources documentation
Program contact
- 👤 National Institutes of Health
- 📧 grantsinfo@nih.gov
- 📞 301-402-2541
Funding track record
Recent awards under CFDA 93.847 from the last 3 years — real organizations that won funding through this same program.
Top 10 Largest Recent Awards
-
$444,814,918
-
$200,221,259
-
$181,279,494
-
$112,529,392
-
$82,457,560
-
$79,214,478
-
$48,585,892
-
$45,186,589
-
$37,997,540
-
$34,242,949
Top States by Funding
- WA 4 awards $520.0M
- NC 4 awards $293.3M
- FL 3 awards $291.6M
- NY 5 awards $184.3M
- PA 6 awards $176.9M
Source: USAspending.gov — federal spending transparency. Data covers last 3 years.
Funding history
Annual funding for this program — Federal obligations (CFDA 93.847). How funding has trended year over year.
| 2024 | $1,971,472,000 | |
| 2025 | $2,043,166,000 | |
| 2026 est. | $111,289,000 |
FAQ
Who can apply for this R21 grant?
Researchers at research institutions, universities, and hospitals with 501(c)(3) status can apply. Applicants must hold a doctoral degree in relevant fields. You need a research mentor or institutional affiliation to submit.
What types of projects are funded?
Pilot studies exploring HIV pathogenesis mechanisms are eligible. Clinical trials are not allowed. Projects should test novel hypotheses with preliminary data.
What is the application deadline?
The deadline is November 16, 2027. Applications open January 8, 2025. Check NIH's grants.gov for exact submission windows.
How competitive is this grant?
R21 grants are moderately competitive. Strong preliminary data and innovative hypotheses improve chances. Clear feasibility within the 2-year project period is essential.
How much funding is available?
R21 awards typically range from $150,000 to $275,000 total costs over two years. Indirect costs are included in this cap. Budget constraints require efficient project design.
💡 Tips for applicants
- Emphasize preliminary data supporting your hypothesis. Reviewers want evidence your pilot is doable in 2 years.
- Align your study directly with NIDDK's mission in HIV, kidney, or metabolic disease interactions.
- Clearly explain how your pilot findings will lead to a larger R01 grant. NIH funds R21s to generate future funding.
- Keep the project scope manageable. Reviewers reject overly ambitious proposals for pilot mechanisms.
- Use simple, clear figures and tables. NIH reviewers read hundreds of applications; make yours easy to follow.
⚠️ Common mistakes
Proposals lack adequate preliminary data supporting feasibility. Scope is too large for a 2-year pilot mechanism. Projects propose clinical trials, which violate R21 restrictions.
Similar grants
- OPEN Priority HIV/AIDS Research within the Mission of NIDDK (R01 Clinical Trial Optional) — National Institutes of Health
- OPEN Development and Testing of Novel Interventions to Improve HIV Prevention, Treatment, and Program Implementation for People Who Use Substances (R34 Clinical Trial Required) — National Institutes of Health
- OPEN Pilot and Feasibility Studies in Preparation for Substance Use and HIV Prevention Intervention and Services Research Trials (R34 Clinical Trial Optional) — National Institutes of Health
- OPEN Development of Models, New Approach Methodologies, and Biological Materials for Studying Human Health and Diseases (R21 Clinical Trial Not Allowed) — National Institutes of Health
- OPEN NIAID Investigator Initiated Program Project Applications (P01 Clinical Trial Not Allowed) — National Institutes of Health