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Human Subjects Research

NIDDK funds human subjects research—including clinical studies and trials—through various funding mechanisms. Before you apply to a funding opportunity announcement (FOA), take the following steps.

If you are applying for or have already received a clinical research grant you must follow both NIH and NIDDK policies for clinical research. You can also review the wide range of NIDDK Research Resources to help clinical researchers work more efficiently, lower costs, and improve effectiveness.

Funding Mechanisms for Human Subjects Research

Pilot/Feasibility Clinical Studies (R21)

The R21 mechanism provides support for exploratory, short-term clinical studies that investigate new ideas and novel approaches with less stringent requirements for preliminary data. Short-term studies should focus on research questions that are likely to have high clinical impact.

Funding is provided through a series of disease-specific FOAs. NIDDK uses the R21 mechanism selectively and many pilot and feasibility projects may not be appropriate for particular NIDDK FOAs, so it is important to read each FOA carefully. View open R21 FOAs from NIDDK.

Clinical Research (R01): One or Two Research Centers

For clinical studies that involve up to two research centers, R01s may be used. A single clinical research center may encompass one or more physical locations where the clinical trial is being conducted—i.e., where study participants are recruited, intervened upon, or have outcomes assessed under a single protocol—as long as all locations are under the overall direction of a single investigator.

Clinical trials within the mission of NIDDK that involve one or two centers may use PA-18-330 or other appropriate FOAs from NIDDK.

Observational studies or other types of human subjects research that is not a clinical trial that involve one or two centers may use the parent NIH R01 FOA or specific FOAs from NIDDK.

Multi-center Clinical Studies (U34/U01): Three or More Research Centers

For clinical studies that involve three or more research centers, NIDDK uses a two-part process that usually requires use of a U34 planning grant followed by a separate application for the clinical trial or study (U01). A single clinical research center may encompass one or more physical locations where the clinical trial is being conducted—i.e., where study participants are recruited, intervened upon, or have outcomes assessed under a single protocol—as long as all locations are under the overall direction of a single investigator.

For more information on the U34, view NIDDK’s U34 page, PAR-18-423, and NOT-DK-14-025.

For more information on the U01, view NIDDK’s U01 page, PAR-18-414PA-18-415, and NOT-DK-14-025.

Investigator-initiated Ancillary Studies to Major Ongoing Clinical Studies

NIDDK encourages ancillary studies to its large multi-center clinical trials and clinical studies. These major studies offer unique opportunities to conduct additional investigations that are not part of the parent protocol. These new studies must be within the mission of NIDDK. Applications for ancillary studies must have the approval of the parent study and may be submitted to PA-19-056 or other appropriate FOAs.

Biosamples for Use in Research (X01)

Many of the large clinical studies funded by the NIDDK collect non-renewable biosamples, such as plasma and urine, and associated data for analysis and future study. Biosamples are stored in the NIDDK Central Repository. The X01 mechanism provides access for researchers who are interested in using these biosample resources in their clinical studies. View PAR-17-270.

Additionally, investigators are encouraged to utilize repository biosamples for the development of assays targeting
NIDDK-relevant diseases through PAR-17-123.

Related Links

NIH Resources