Ancillary Studies to Ongoing Clinical Projects (R21 Clinical Trial Not Allowed) | PAR 23 026

Opportunity Information: Apply for PAR 23 026

The Ancillary Studies to Ongoing Clinical Projects (R21 Clinical Trial Not Allowed) funding opportunity (PAR 23-026) is a discretionary NIH grant program designed to support smaller, targeted research projects that add value to clinical studies that are already underway. The emphasis is on "ancillary" work, meaning the proposed research should be clearly tied to an active, existing clinical project and should leverage the parent study's infrastructure, participants, specimens, data systems, or other established resources. This opportunity uses the NIH R21 mechanism, which is commonly used for exploratory or developmental research that can be completed with a limited budget and within a relatively focused scope, particularly when the goal is to answer a specific question or generate preliminary data that can inform larger future studies.

A key limitation is embedded directly in the title: clinical trials are not allowed under this announcement. In practical terms, the application should not propose a new clinical trial, nor should it introduce trial-like elements that would constitute a new interventional study. Instead, the work should be ancillary to an ongoing clinical effort, typically involving analyses of already-collected or prospectively collected samples or data within the boundaries of the existing clinical project, or methodological and mechanistic investigations that do not introduce a new interventional protocol. The project should stand on its own as a scientifically meaningful question while also being feasible because it piggybacks on the parent clinical study.

The sponsoring agency is the National Institutes of Health, and the funding activity area is health (CFDA 93.846). While the listing does not specify an award ceiling or the number of expected awards, the R21 format generally signals a limited, focused budget appropriate for a discrete set of aims rather than a large multi-year program. The opportunity was created on 2022-11-21, and the original closing date shown is 2025-12-05, which indicates applicants should plan around that submission window while also verifying any updated due dates or application cycles in the full NIH notice.

Eligibility is broad and includes many types of U.S.-based organizations and governmental entities. Eligible applicants include state, county, city or township governments; special district governments; independent school districts; public and state-controlled institutions of higher education; private institutions of higher education; and Native American tribal governments that are federally recognized. It also includes public housing authorities/Indian housing authorities, and tribal organizations that are not federally recognized tribal governments. On the nonprofit side, both 501(c)(3) nonprofits (other than institutions of higher education) and nonprofits without 501(c)(3) status (again, other than institutions of higher education) may apply. For-profit organizations other than small businesses are eligible, as are small businesses, and the notice also lists "others," which typically captures additional eligible organization types recognized in NIH policy.

The announcement also explicitly calls out additional eligible applicants, reflecting NIH's inclusion of a wide range of institutions and community-based entities. These include Alaska Native and Native Hawaiian Serving Institutions, Asian American Native American Pacific Islander Serving Institutions (AANAPISIs), Hispanic-serving Institutions, Historically Black Colleges and Universities (HBCUs), and Tribally Controlled Colleges and Universities (TCCUs). Faith-based or community-based organizations are also included, as are eligible agencies of the federal government, regional organizations, Indian/Native American tribal governments other than federally recognized ones, and U.S. territories or possessions. This breadth is important because it signals that ancillary studies can be proposed by many different organizational types, including those that may be closely connected to participant communities or that manage key clinical infrastructure.

Foreign eligibility is more restrictive. Non-domestic (non-U.S.) entities (foreign institutions) are not eligible to apply as applicant organizations, and non-domestic components of U.S. organizations are also not eligible to apply. However, the notice states that foreign components, as defined in the NIH Grants Policy Statement, are allowed. In NIH terms, that typically means a U.S. applicant organization can include certain well-justified foreign elements of the work (for example, specific analyses or collaborations conducted abroad) when they are necessary and appropriately structured, even though a non-U.S. institution cannot be the primary applicant.

Overall, this opportunity is best suited for investigators who have access to an ongoing clinical project and can articulate a strong scientific rationale for an add-on study that is efficient, feasible, and clearly dependent on the parent project. Competitive proposals will usually make the relationship to the ongoing clinical study unmistakable, explain what unique value the ancillary work adds, and show that the work can be completed without launching a new clinical trial or altering the parent study in a way that crosses into trial activity.

• The National Institutes of Health in the health sector is offering a public funding opportunity titled "Ancillary Studies to Ongoing Clinical Projects (R21 Clinical Trial Not Allowed)" and is now available to receive applicants.
• Interested and eligible applicants and submit their applications by referencing the CFDA number(s): 93.846.
• This funding opportunity was created on 2022-11-21.
• Applicants must submit their applications by 2025-12-05. (Agency may still review applications by suitable applicants for the remaining/unused allocated funding in 2026.)
• Eligible applicants include: State governments, County governments, City or township governments, Special district governments, Independent school districts, Public and State controlled institutions of higher education, Native American tribal governments (Federally recognized), Public housing authorities/Indian housing authorities, Native American tribal organizations (other than Federally recognized tribal governments), Nonprofits having a 501 (c) (3) status with the IRS, other than institutions of higher education, Nonprofits that do not have a 501 (c) (3) status with the IRS, other than institutions of higher education, Private institutions of higher education, For-profit organizations other than small businesses, Small businesses, Others.

Apply for PAR 23 026

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