Mechanistic Ancillary Studies to Ongoing Interventional Clinical Trials (R21) | RFA AR 18 003

Opportunity Information: Apply for RFA AR 18 003

The NIH funding opportunity titled "Mechanistic Ancillary Studies to Ongoing Interventional Clinical Trials (R21)" (Funding Opportunity Number RFA-AR-18-003; CFDA 93.846) was designed to support short, time-sensitive mechanistic studies that can be added onto an interventional clinical trial that is already underway. It is administered within the NIH and aligns with the mission of NIAMS, meaning the science should be relevant to diseases and organ systems in NIAMS portfolios (for example, arthritis and musculoskeletal conditions, skin diseases, and related immune-mediated disorders). Rather than funding a brand-new clinical trial, the intent is to take advantage of an existing trial that already has a defined patient cohort, established operational infrastructure, and ongoing collection of clinical data and, importantly, access to biological samples.

A central requirement is that the "parent" project must be an ongoing interventional clinical trial (privately or publicly funded) that can provide what the ancillary project needs to succeed: well-characterized participants, trial infrastructure, usable data streams, and biological specimens. The ancillary study is expected to be mechanistic, meaning it should dig into how a treatment works, why a response happens (or does not), what biological pathways are affected, or what measurable biomarkers track with outcomes. The FOA emphasizes that these add-on studies should be time-sensitive, which typically reflects the reality that sample collection windows and trial milestones cannot be recreated later. Because of that urgency, applications under this announcement were set up to go through an accelerated review and award process so that the ancillary work can be initiated while the parent trial is still positioned to support it.

Programmatically, the goal is efficiency and added scientific value. NIH is essentially saying: a lot of money and effort has already been invested in launching and running the parent interventional trial, so an R21 mechanism can be used to leverage that investment by funding targeted mechanistic questions that the parent trial was not originally designed or resourced to answer. If successful, these ancillary studies should increase the overall scientific yield of the parent trial, deepen understanding of the underlying disease biology or organ system function within the NIAMS mission space, and potentially point toward new targets for diagnosis, treatment, or prevention. In other words, the outcome is not just an incremental add-on; it is meant to meaningfully enhance the interpretability and downstream impact of the existing clinical trial.

The funding mechanism is an NIH R21, which generally supports exploratory and developmental research and is often used for focused projects that can produce high-value insights without requiring the scale of a full R01. For this specific FOA, the listed award ceiling is $250,000. The opportunity is categorized as discretionary and uses the grant funding instrument type, within the health funding activity category. The original closing date shown is 2018-04-02, and the FOA was created on 2017-05-01, which helps place it historically as a time-limited solicitation rather than an always-open program.

Eligibility is broad and includes many types of U.S.-based organizations and governmental entities. Examples listed include state, county, and local governments; special district governments; independent school districts; public and state-controlled institutions of higher education; private institutions of higher education; federally recognized Native American tribal governments; tribal organizations that are not federally recognized; public housing authorities/Indian housing authorities; nonprofits with and without 501(c)(3) status (outside of higher education); for-profit organizations (other than small businesses); small businesses; and other eligible applicants. The FOA also explicitly calls out additional eligible applicant categories such as Alaska Native and Native Hawaiian Serving Institutions, AANAPISIs, Hispanic-serving Institutions, Historically Black Colleges and Universities (HBCUs), Tribally Controlled Colleges and Universities (TCCUs), faith-based or community-based organizations, regional organizations, eligible federal agencies, tribal governments other than federally recognized, and U.S. territories or possessions.

At the same time, there are clear limits around non-U.S. involvement. Non-domestic (non-U.S.) entities (foreign organizations and foreign institutions) are not eligible to apply, and non-domestic components of U.S. organizations are also not eligible to apply. However, "foreign components" as defined in the NIH Grants Policy Statement are allowed, which typically means a U.S. applicant organization can include certain foreign elements in the project when scientifically justified and compliant with NIH policy, even though the applicant institution itself must be domestic.

Overall, the opportunity is best understood as a fast-moving, add-on funding pathway intended to capitalize on the unique scientific window created by an ongoing interventional trial. It supports mechanistic work that can use the trial's participants, systems, and specimens to answer questions about biology and response that would otherwise be difficult, expensive, or impossible to study after the trial ends.

• The National Institutes of Health in the health sector is offering a public funding opportunity titled "Mechanistic Ancillary Studies to Ongoing Interventional Clinical Trials (R21)" 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 2017-05-01.
• Applicants must submit their applications by 2018-04-02. (Agency may still review applications by suitable applicants for the remaining/unused allocated funding in 2026.)
• Each selected applicant is eligible to receive up to $250,000.00 in funding.
• 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 RFA AR 18 003

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