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

Frequently Asked Questions (FAQs)

What is the purpose of the NIH funding opportunity "Mechanistic Ancillary Studies to Ongoing Interventional Clinical Trials (R21)"?

This funding opportunity is designed to support short, time-sensitive mechanistic studies that can be added onto an interventional clinical trial that is already underway. The goal is to leverage an existing trial's participants, operational infrastructure, ongoing clinical data collection, and access to biological samples to answer mechanistic questions the parent trial was not originally designed to address.

What is the Funding Opportunity Number (FOA) for this grant?

The Funding Opportunity Number is RFA-AR-18-003.

What is the CFDA number associated with this opportunity?

The CFDA number listed is 93.846.

What type of grant mechanism is used for this opportunity?

This opportunity uses the NIH R21 mechanism, which generally supports exploratory and developmental research and is suited for focused projects intended to generate high-value insights without the scale of a full R01.

What is the maximum award amount for this FOA?

The listed award ceiling for this FOA is $250,000.

Does this FOA fund brand-new clinical trials?

No. The intent is not to fund a new clinical trial. Instead, the FOA supports ancillary mechanistic studies that add onto an existing interventional clinical trial that is already in progress.

What qualifies as the required "parent" project for an ancillary study application?

The parent project must be an ongoing interventional clinical trial (either privately or publicly funded). It must be positioned to support the ancillary mechanistic study by providing access to well-characterized participants, trial infrastructure, usable data streams, and biological specimens.

What does "ancillary" mean in the context of this FOA?

"Ancillary" refers to an add-on study that is attached to an existing interventional clinical trial. The ancillary project is intended to use the parent trial's established cohort and operations to efficiently address additional scientific questions.

What does "mechanistic" mean for the purposes of this opportunity?

A mechanistic ancillary study is expected to examine how and why an intervention works (or does not work). This can include investigating biological pathways affected by treatment, reasons for variable responses among participants, or identifying measurable biomarkers that track with clinical outcomes.

Why does the FOA emphasize that the ancillary studies must be time-sensitive?

The FOA emphasizes time-sensitivity because the parent trial creates unique windows for sample collection and clinical milestones that cannot be recreated later. The ancillary work needs to begin while the parent trial is still underway and able to support required data and specimen collection.

Is there anything about the review or award process that reflects the time-sensitive nature of these studies?

Yes. The FOA indicates that applications were set up for an accelerated review and award process to help ensure the ancillary study can be initiated while the parent trial is still positioned to support it.

Which NIH mission area does this FOA align with?

This opportunity aligns with the mission of NIAMS. The proposed science should be relevant to diseases and organ systems within NIAMS portfolios, such as arthritis and musculoskeletal conditions, skin diseases, and related immune-mediated disorders.

What is NIH trying to achieve by funding ancillary mechanistic studies instead of starting new trials?

The programmatic goal is efficiency and increased scientific value. NIH aims to leverage the substantial investment already made in running the parent interventional trial by funding targeted mechanistic questions the parent trial was not originally resourced to answer. Successful projects are intended to increase the overall scientific yield and interpretability of the parent trial and deepen understanding of relevant disease biology.

What kinds of resources from the parent trial are considered important for the ancillary study?

The FOA highlights several key resources: a defined and well-characterized participant cohort, established operational infrastructure, ongoing collection of clinical data, and access to biological samples/specimens.

How should the ancillary study impact the parent clinical trial?

The ancillary study is intended to meaningfully enhance the scientific yield of the parent trial. Rather than being purely incremental, it should improve interpretability and downstream impact by providing mechanistic insights, such as clarifying biological pathways, understanding response variability, or identifying biomarkers linked to outcomes.

What funding instrument type and activity category are indicated?

The opportunity uses the grant funding instrument type and falls within the health funding activity category. It is described as discretionary.

When was this FOA created and when did it close?

The FOA was created on 2017-05-01, and the original closing date shown is 2018-04-02. This places it as a time-limited solicitation rather than an always-open program.

Who is eligible to apply?

Eligibility is broad and includes many types of U.S.-based organizations and government 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.

Are any specific institution types explicitly called out as eligible?

Yes. The FOA explicitly mentions eligibility for 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.

Are non-U.S. (foreign) organizations eligible to apply?

No. Non-domestic (non-U.S.) entities, including foreign organizations and foreign institutions, are not eligible to apply under this FOA.

Can a U.S. organization apply if the project includes a non-U.S. component?

Non-domestic components of U.S. organizations are not eligible to apply. However, "foreign components" (as defined in the NIH Grants Policy Statement) are allowed when scientifically justified and consistent with NIH policy, even though the applicant institution itself must be domestic.

What is the basic idea behind allowing foreign components but not allowing foreign applicants?

Based on the FOA language, the applicant organization must be U.S.-based, but the project may include certain foreign elements as a "foreign component" when appropriate and compliant with NIH policy. This allows scientifically justified international elements without making foreign institutions eligible as the primary applicant.

What is the best overall way to think about this funding opportunity?

It is a fast-moving, add-on funding pathway intended to capitalize on the unique scientific window created by an ongoing interventional clinical trial. It supports mechanistic research that uses trial participants, systems, data, and specimens to answer biology and treatment-response questions that would be difficult, expensive, or impossible to study after the trial ends.