Pilot Studies of Biological, Behavioral and Social Mechanisms Contributing to HIV Pathogenesis Within the Mission of NIDDK (R21 Clinical Trial Not Allowed)

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health (NIH), has issued a funding opportunity announcement titled "Pilot Studies of Biological, Behavioral and Social Mechanisms Contributing to HIV Pathogenesis Within the Mission of NIDDK." This opportunity, under the R21 exploratory/developmental grant mechanism, is designed to support innovative pilot research projects that explore the mechanisms by which HIV and its treatment affect systems and diseases relevant to NIDDK’s mission. This reissued opportunity (PAR-25-068) aligns with the NIH Office of AIDS Research priorities as articulated in NOT-OD-20-018 and reflects updated NIH policies including those affecting genomic data sharing and application reviews. The purpose of this Notice of Funding Opportunity (NOFO) is to support basic and translational HIV research addressing comorbidities, coinfections, and complications (CCCs) within the scope of NIDDK. These may include, for example, enteropathy, liver diseases, kidney disease, and metabolic disorders. It also targets research into viral reservoirs within relevant tissues like the gastrointestinal tract, male genital tract, kidney, and adipose tissue. The impact of social determinants of health (SDoH) on HIV outcomes—such as housing instability, food insecurity, and stigma—is also a focus. This funding is intended for exploratory studies, enabling investigators to generate preliminary data that may lead to larger-scale projects (e.g., R01-level applications). Funding may be used to support research involving human subjects, animal models, or analysis of non-identifiable data or biospecimens. The scope is inclusive of epidemiological and observational studies into environmental, behavioral, and psychosocial contributors to HIV pathogenesis. The program does not support clinical trials, and applicants with clinical trial proposals are directed to a different funding mechanism (PAS-25-102). Applications must adhere to NIH’s updated policies, including those regarding data sharing and study rigor. Eligible applicants include U.S.-based institutions of higher education, nonprofits, state and local governments, tribal organizations, and for-profit organizations including small businesses. Foreign institutions may not apply, although foreign components may be included in U.S.-based projects. Applicants must complete all required registrations including SAM.gov, eRA Commons, and Grants.gov. The total direct cost for a two-year project must not exceed $275,000, and no more than $200,000 may be requested in a single year. Applications are accepted on NIH’s AIDS standard due dates, with the earliest submission date being April 7, 2025. Upcoming deadlines include May 7, 2025, September 7, 2025, and January 7, 2026, with corresponding peer review and award cycles. Applications must be submitted electronically using the NIH ASSIST system, Grants.gov Workspace, or institutional system-to-system platforms. Conformance to all instructions in the Application Guide and this NOFO is required; applications that do not meet these standards may be withdrawn without review. Program-specific contacts include Dr. Khoa Dinhdang Nguyen for digestive and nutritional research, Dr. Deepak Nihalani for kidney and urologic diseases, and Dr. Saul Malozowski for metabolic and endocrine research. Grants management questions should be directed to Sunshine Wilson. The earliest start dates for successful applications will range from December 2025 to July 2028, depending on the review cycle. This NOFO will expire on May 8, 2026, per Notice NOT-OD-26-029.

Applicants are strongly encouraged to contact NIDDK staff early to ensure alignment with institute priorities; non-aligned proposals are administratively withdrawn.