Animal Models for Hepatitis B and C (R01 Clinical Trial Not Allowed) | RFA AI 23 022

Frequently Asked Questions (FAQs)

What is the funding opportunity called and what is its FOA number?

The National Institutes of Health (NIH) Funding Opportunity Announcement (FOA) is RFA-AI-23-022, titled "Animal Models for Hepatitis B and C (R01 Clinical Trial Not Allowed)."

What is the main purpose of this FOA?

The FOA is intended to push hepatitis research toward better, more practical experimental models for hepatitis B virus (HBV) and hepatitis C virus (HCV). The core objective is to develop convenient small animal models (or closely related alternative systems) that can support viral infection and replication and that can reproduce clinically relevant outcomes.

What specific outcomes does NIH want these models to reproduce?

NIH emphasizes two key, real-world outcomes observed in people: viral clearance versus long-term persistence (chronic infection). The FOA highlights strong interest in models that can be used to study why some hosts eliminate infection while others develop chronic disease.

Does the FOA want models that only allow viral entry or short-lived replication?

No. The FOA signals that it is looking for systems that go beyond merely permitting viral entry or transient replication. Applicants are expected to develop models that can help investigate mechanisms that drive clearance versus persistence.

Are only traditional small animal models allowed, or are alternative approaches acceptable?

Alternative approaches are acceptable if they achieve the same scientific goals. The FOA welcomes closely related surrogate virus-host systems and xenotransplantation strategies, alongside straightforward small animal model development.

What does the FOA say about humanized or xenograft-based models?

The FOA explicitly includes robust humanized or xenograft-based models, particularly approaches designed to be dually engrafted with human liver cells and a human immune system.

Why is dual engraftment (human liver cells plus human immune system) emphasized?

Because HBV and HCV outcomes are strongly shaped by interactions between infected hepatocytes and immune responses. Models that incorporate both compartments can better capture immune control, immune failure, immunopathology, and pathways to persistence.

What kinds of scientific questions are these models expected to enable?

Based on the FOA description, the intent is to expand tools for studying viral life cycles, host responses, determinants of chronic infection, and host-pathogen dynamics. The emphasis is on systems that are accessible enough to be widely used and that more closely mirror clinically relevant biology.

What grant mechanism is used for this opportunity?

This opportunity uses the NIH R01 grant mechanism.

Are clinical trials allowed under this FOA?

No. The FOA is labeled "Clinical Trial Not Allowed," meaning it is aimed at preclinical and mechanistic model development rather than testing interventions in human participants.

What activity area and assistance listing (CFDA) is associated with this FOA?

It is described as a discretionary grant in the health activity area, associated with CFDA 93.855.

When was this FOA created and what was the original closing date listed?

The announcement was created on March 28, 2023, and the original closing date listed was August 25, 2023.

Is there an award ceiling (maximum funding amount) provided in the information here?

No. An award ceiling is not specified in the provided source information.

Is the expected number of awards provided in the information here?

No. The expected number of awards is not listed in the provided source information.

Where should applicants look for budget guidance or project period expectations?

Because the award ceiling, number of awards, and other budget-related details are not provided in the source information here, applicants would need to consult the full FOA for budget guidance, project period expectations, and any institute- or program-specific limits.

Who is eligible to apply?

Eligibility is broad and includes many types of applicants. Domestic eligibility includes: state, county, city or township 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 other than federally recognized tribal governments; public housing authorities/Indian housing authorities; nonprofits with or without 501(c)(3) status (other than higher education institutions); for-profit organizations (other than small businesses); and small businesses.

Are mission-focused or special-designation institutions specifically highlighted as eligible?

Yes. The FOA highlights additional eligible applicants such as Alaska Native and Native Hawaiian Serving Institutions; Asian American Native American Pacific Islander Serving Institutions (AANAPISIs); Hispanic-serving Institutions; Historically Black Colleges and Universities (HBCUs); Tribally Controlled Colleges and Universities (TCCUs); and faith-based or community-based organizations.

Are federal entities and U.S. territories mentioned as eligible?

Yes. The FOA mentions eligible agencies of the federal government, U.S. territories or possessions, and regional organizations as eligible applicants.

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

Yes. The FOA includes non-domestic (non-U.S.) entities (foreign organizations) in its eligibility language.

What is the overall intent of NIH in issuing this FOA?

The overall intent is to catalyze the next generation of HBV and HCV experimental systems that are easier to use, biologically faithful, and capable of modeling the critical divergence between resolving infection and developing chronic disease. NIH is aiming to enable downstream advances across hepatitis research by improving models for studying viral replication, immune control, persistence, and long-term host-pathogen dynamics.