Microbial-based Cancer Imaging and Therapy - Bugs as Drugs (R21 Clinical Trial Not Allowed) | PAR 25 108

Opportunity Information: Apply for PAR 25 108

The National Cancer Institute (NCI) is offering an exploratory R21 grant opportunity called "Microbial-based Cancer Imaging and Therapy - Bugs as Drugs (R21 Clinical Trial Not Allowed)" (PAR-25-108). The program is aimed at early-stage, higher-risk research that tests bold ideas using microorganisms and their natural products to better understand, and potentially harness, the relationship between microbes, tumors, and the immune system. The overall goal is to generate new mechanistic insights and preclinical proof-of-concept data that could open up new directions for cancer imaging, diagnostics, and therapy based on microbial systems.

The scientific focus centers on using bacteria, archaebacteria, bacteriophages, and other non-oncolytic viruses (as well as products derived from these organisms) as tools or agents in cancer-related applications. Projects can investigate microorganisms as direct anti-tumor agents, as stimulators or modulators of anti-tumor immune responses, or as delivery vehicles that carry therapeutic, diagnostic, or imaging payloads to tumors. Applications can also propose approaches that complement or synergize with existing cancer technologies and treatment strategies rather than replacing them, which leaves room for combination concepts at the preclinical level.

This NOFO emphasizes understanding the underlying mechanisms that govern complex microbe-tumor-immune interactions. Applicants are encouraged to address both sides of the biology: the microbial traits that enable tumor targeting, persistence, immune activation, or payload delivery, and the tumor and host factors that shape microbial localization, function, safety, and therapeutic effect. The opportunity explicitly includes relevance to microbial-based cancer therapy for oral cancer as well as broader applications in tumor imaging, tumor detection, and diagnostic development.

The work supported under this R21 is limited to basic mechanistic and preclinical studies, meaning experiments should be conducted in cell culture systems and animal models rather than in human participants. As stated in the title, clinical trials are not allowed under this funding opportunity. The R21 mechanism is meant for projects that are still in the feasibility or early development phase (from inception through preliminary development), where the main deliverable is evidence that the core concept can work and that the approach has a credible path forward. NCI signals that considerable risk is acceptable, and that the research should be positioned to produce potential breakthroughs in microbial-based cancer therapy, imaging, or diagnosis.

In terms of eligibility, the opportunity is broadly open across many organization types. Eligible applicants include various levels of government (state, county, city/township, special districts), independent school districts, public and private institutions of higher education, federally recognized Native American tribal governments and other tribal organizations, public housing authorities/Indian housing authorities, nonprofits with or without 501(c)(3) status, for-profit organizations (other than small businesses), and small businesses. The announcement also highlights additional eligible applicant categories such as Alaska Native and Native Hawaiian Serving Institutions, AANAPISISs, Hispanic-serving Institutions, Historically Black Colleges and Universities (HBCUs), Tribally Controlled Colleges and Universities (TCCUs), faith-based or community-based organizations, eligible federal agencies, U.S. territories or possessions, regional organizations, and foreign (non-U.S.) entities.

Administratively, this is a discretionary grant opportunity from the National Institutes of Health (NIH) under NCI, associated with CFDA numbers 93.121, 93.395, and 93.396. The funding opportunity was created on 2024-11-12, and the listed original closing date is 2025-05-07. The posted summary does not provide an award ceiling or expected number of awards, so applicants would need to consult the full NOFO for budget limits, project period expectations, and any institute-specific review considerations.

• The National Institutes of Health in the education, health sector is offering a public funding opportunity titled "Microbial-based Cancer Imaging and Therapy - Bugs as Drugs (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): 93.121, 93.395, 93.396.
• This funding opportunity was created on 2024-11-12.
• Applicants must submit their applications by 2025-05-07. (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 25 108

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