Biomedical researchers with linkage to the NIH have weathered a lot of changes in recent years. In fact, you’re likely noticing some shifting expectations that may not always be clearly spelled out. The recent NIH announcement—Funding Alignments with the Initiative to Prioritize Human-Based Research—is one such signal. This announcement portends a new vision for how the NIH prioritizes approaches to discovery, and it understandably creates some questions for those seeking NIH funding. In fact, during a recent seminar on applying for NIH R01s, we received a question on how to navigate “the NIH ban on animal models”; we don’t fault the audience member who asked the question, because while there is no such ban, there is cause for confusion. We also recognize that this question represents the fact that investigators are worried about how to pursue and present their research. Whether you’re a postdoctoral fellow designing your first independent project, early-career faculty navigating tenure-track pressures, or a seasoned PI steering an established lab, NIH’s announcement could represent both a challenge and an opportunity. Let’s break down the policy and look at how to move forward with clarity.

Has the NIH Banned Animal Models?

No, as of the 2025 announcement, the NIH is not banning animal research. This is a crucial distinction that bears repeating in conversations with concerned trainees and collaborators. The initiative calls for funding announcements and grant application review to “align with” a prioritization toward human-relevant research. In other words:

• Funding announcements that the NIH releases will not center on animal models. For example, a funding opportunity released in 2023 called for “Animal Models of Hepatitis B and C.” In the future, such a notice would have to be broad enough to include other types of approaches (e.g., human tissue models, in silico models, real-world data) in addition to animal models.
• Grant application review will consider whether animal models are complemented by other approaches to shore up the translational relevance. Programmatic decisions may prioritize studies with human-based approaches to encourage more diverse approaches.

Through this lens (and in the NIH’s own words), the use of animal models is still allowed and remains acceptable.

That said, in practice, this policy shift means the scientific community is being asked to raise its standards of justification. Where animal models were once the default starting point for many investigations, they are now being positioned as one tool among many in a sophisticated toolkit. This is not a rejection of past science built on animal work, but an evolution toward a more deliberate and integrated approach to experimental design to ensure that findings have human relevance.

The practical implications fall across three key dimensions:

Scrutiny: Proposals relying heavily on animal models may face a higher bar. Ensure that your justification provides a scientifically rigorous narrative that convincingly argues why an animal model is necessary for your specific question. Also, be sure to include power calculations and other evidence to support your sample sizes, and emphasize when you’ve taken steps to minimize the number of animals used.

Human-Relevance Front and Center: The “why” behind your model choice needs to be explicit and woven throughout your proposal’s narrative. How will this animal work directly inform human biology, disease mechanisms, or therapeutic development? The direct line to human application must be clear, not as an afterthought, but as the central thesis of your investigation. Consider dovetailing your animal model studies with other approaches (human tissue samples, organoids, and human datasets) that will support the translational connection.

Exploring Alternatives First: NIH’s announcement indicated that they are investing in training and education on the many other non-animal model approaches and are guiding POs and grant reviewers to detect bias towards animal models. So, before defaulting to an animal system, consider the landscape of human-based alternatives—from established cell lines and patient-derived organoids to sophisticated organ-on-a-chip systems, human genomics databases, and advanced computational modeling approaches. If you’re not incorporating those approaches, or they take only a small role in your project, make it clear that the alternatives are insufficient for the specific question you’re addressing.

On a big-picture level, you’ll want to approach your experimental design by knowing what question(s) you want to answer and then working backwards to determine what combination of approaches will most directly answer the question. In this way, animal models become specialized tools within the larger toolkit.

Navigating the New Landscape: A Strategic Guide for Investigators

So, how do you adapt your grant-writing and research strategy to this evolving landscape? Here’s a practical, actionable approach that may help you adopt the perspective that this shift represents an opportunity to expand your scientific capabilities and the impact of your discoveries.

1. Rethink Your Proposal’s Narrative Arc
Consider framing your work as a problem with relevance to human health, whether you’re doing basic, clinical, or translational science. This human-centered foundation sets the stage for everything that follows. Then, position any proposed animal work as a precision tool that, when combined with other approaches, equips you to solve the problem. This narrative structure—from human question to animal models to human-based or human-relevant models/data—naturally aligns with the NIH’s strategic direction while maintaining scientific rigor.

2. Build a Rigorous “Model Justification” Section
Treat this as a critical part of your experimental design rather than administrative boilerplate. Dedicate thoughtful space to delineate:

• Which alternatives you considered and why they’re insufficient on their own (or at all).  Use citations where you can to justify why you’ve not chosen particular models or approaches.
• Why the chosen animal model is the best possible system to answer this question. What aspects of human biology does it faithfully model? Where does it diverge, and how will you account for those differences? Again, use evidence (citations, preliminary data, etc.) to back up your claims.
• How you are approaching your animal use with rigor. Show that you take animal welfare and usage seriously, and justify with power calculations and experimental practices how you are ensuring that you’ll produce rigorous and reproducible results while also minimizing animal numbers and distress.

3. Integrate, Don’t Isolate
The most competitive proposals will likely be hybrids that leverage the unique strengths of multiple systems. For example, a project might use patient-derived organoids to discover a novel mechanism in a human tissue, validate and further dissect the key finding in a relevant and tractable animal model, and then correlate back to human tissue samples or clinical data to confirm relevance. Such integration shows that your choice of animal models is part of an overall strategy to leverage the strengths of each system or approach to answer the scientific question.

4. Leverage the Right Funding Opportunities
Pay close attention to the specific language in Notice of Funding Opportunities (NOFOs), as nuance matters more than ever. Look for NOFOs from institutes strongly championing this initiative, announcements emphasizing “human subjects research,” “human-based models,” “translational,” or “clinical relevance,” and programs specifically supporting early-stage development of human-focused technologies. Your targeted grant search should now include filters for these terms, and your reading of NOFOs should extend beyond scientific scope to methodological expectations.

The Bottom Line: An Opportunity for Better Science

This transition may feel challenging, especially for labs with deep expertise in specific animal models. Yet it is fundamentally an opportunity to be more critical in experimental planning and more creative in methodological combinations, with the potential for biomedical impacts to be more directly relevant to human health. Taking an expansive rather than narrow view is also an invitation to cultivate more collaborative projects where investigators can bring their unique tools and expertise together.

Do you have questions or insights on adapting to these changes? Share your thoughts or reach out for a deeper discussion on strategic grant planning. CareerVolt specializes in helping researchers at all career stages navigate these evolving expectations while maintaining scientific excellence and funding competitiveness.