Comparison of NIH Small R-Series Research Grants (R03 vs. R21)

By Bouvier Grant Group

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In preparation for discussing the fate of small research grant awards at NIH, I decided first to give a brief overview of the R03 and R21 programs, including a list of which ICs participate in these programs, both under the parent FOA and outside the parent FOA:

Small Research Grant Program (R03)

Maximum two-year award, $50K per year in directs (Six-page application.)

Eleven of the 27 NIH ICs currently participate in the parent award: NHGRI, NIDA, NIA, NIAAA, NIAID, NIBIB, NICHD, NIEHS, NIMH, NINDS, and NINR. (Some of the ICs that are not listed may have R03 programs that fall outside these guidelines that are announced in specific RFAs or PAs issued by the IC.  In other words, they are not investigator-initiated, but rather are tied to specific priority areas for the IC.)

 Purpose: The R03 grant mechanism supports different types of projects including:

  • Pilot or feasibility studies
  • Secondary analysis of existing data
  • Small, self-contained research projects
  • Development of research methodology
  • Development of new research technology

Because the research plan is restricted to six pages, an R03 grant application will not have the same level of detail or extensive discussion found in an R01 application. Accordingly, reviewers should evaluate the conceptual framework and general approach to the problem, placing less emphasis on methodological details and certain indicators traditionally used in evaluating the scientific merit of R01 applications including supportive preliminary data. Appropriate justification for the proposed work can be provided through literature citations, data from other sources, or from investigator-generated data. Preliminary data are not required, particularly in applications proposing pilot or feasibility studies. (But lets face it, you really have to include preliminary data if you want the reviewers to take the application seriously.)

NIH Exploratory Developmental Research Grant Program (R21)

Maximum two-year award, $275K in directs total (no more than $200K in any one year) (Six-page app)

Out of 27 ICs, 19 (soon to be 18) currently participate, and that number is expected to drop: NEI, NHLBI, NHGRI, NLM, NIA, NIAAA, NIAID, NIAMS, NIBIB, NICHD, NIDCD, NIDA, NIDCR, NIDDK (leaving soon), NIEHS, NIMH, NINDS, NINR, NCCAM.

ICs that do not participate in the parent FOA but accept R21 applications in response to their specific FOAs: FIC, NCI, NCMHD, NCRR, NIGMS. For example: NCI reports that they currently have 59 R21 FOAs, 34 of which they initiated. They awarded 229 new R21s in 2010 (as compared to 850 new R01s). They fund a total of 592 R21s (compared to 3998 R01s).

 Purpose of Parent FOA: The Exploratory/Developmental Grant (R21) mechanism is intended to encourage exploratory and developmental research projects by providing support for the early and conceptual stages of these projects. These studies may involve considerable risk but may lead to a breakthrough in a particular area, or to the development of novel techniques, agents, methodologies, models, or applications that could have a major impact on a field of biomedical, behavioral, or clinical research. Such projects could assess the feasibility of a novel area of investigation or a new experimental system that has the potential to enhance health-related research.  Another example could include the unique and innovative use of an existing methodology to explore a new scientific area.

Applications for R21 awards should describe projects distinct from those supported through the traditional R01 mechanism. For example, long-term projects, or projects designed to increase knowledge in a well-established area, will not be considered for R21 awards. Applications submitted under this mechanism should be exploratory and novel. These studies should break new ground or extend previous discoveries toward new directions or applications. Projects of limited cost or scope that use widely accepted approaches and methods within well established fields are better suited for the R03 small grant mechanism. (may submit without preliminary data. NOT.)

(Data and most of the text have been taken from the NIH website. Italics for emphasis, as well as any/all sarcasm, are strictly the author’s.)

Dr. Meg Bouvier

Margaret Bouvier received her PhD in 1995 in Biomedical Sciences from the Mount Sinai School of Medicine. After an NINDS post-doctoral fellowship, she worked as a staff writer for long-standing NIH Director Dr. Francis Collins in the Office of Press, Policy, and Communications for the Human Genome Project and NHGRI. Since 2007, Meg has specialized in editing and advising on NIH submissions, and began offering virtual courses in 2015. She's recently worked with more than 40% of the nation's highest-performing hospitals*, four of the top 10 cancer hospitals, three of the top five medical schools for research, and 14 NCI-designated cancer centers. Her experience at NIH as both a bench scientist and staff writer greatly informs her approach to NIH grantwriting. She has helped clients land over half a billion in federal funding. Bouvier Grant Group is a woman-owned small business.

*Our clients include 9 of the top 22 hospitals as recognized by the 2023/24 US News & World Report honor roll

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