Overview
On April 10, 2025, the US Food and Drug Administration (FDA) announced its intent to phase out the use of animal testing in the development of certain drugs and biologics. To help bring this “paradigm shift in drug evaluation” to fruition, FDA is offering pharmaceutical companies incentives such as faster approval times and reduced testing requirements if they leverage emerging technologies that FDA believes hold the promise of cheaper, safer, and more ethical drug development processes. Although FDA’s sights are currently set on obviating the need for animal testing specifically in monoclonal antibody trials, the agency emphasized in the announcement its desire to expand its efforts to all future applicable use cases.
Background
For several decades, animal testing has been a foundational part of drug and biologics research and development in the United States. To some industry stakeholders, this approach has proven overly costly and provided only mixed benefit. Critics argue that, beyond the skyrocketing prices to procure lab animals (sometimes tens of thousands of dollars per animal in the case of non-human primates), physiological, biochemical, and behavioral differences between humans and model organisms can generate both false hopes and red flags. Sometimes, serious under-the-radar adverse effects are not detected until human trials take place. Many advocacy groups raise moral and ethical concerns related to pain and other harms inflicted by arguably avoidable animal testing.
Until recently, sponsors were required under the Federal Food, Drug, and Cosmetic Act of 1938 to test all products on animals as a safety measure prior to testing them on humans. In September 2022, Congress passed the FDA Modernization Act 2.0, which removed the requirement that sponsors engage in animal testing to support an investigational new drug application (IND), instead allowing them to generate and provide supportive data through various other means. In February 2024, Congress introduced the FDA Modernization Act 3.0, which was meant to push FDA to implement the earlier statute. A bipartisan group in the Senate reintroduced Act 3.0 in January 2025 shortly after the change in administration. Many modern policymakers have welcomed innovative technologies discussed further below as offering better alternatives to animal research.
In Depth
In the April 10, 2025, announcement, FDA Commissioner Marty A. Makary, MD, laid out an ambitious three-year roadmap “to make animal studies the exception rather than the norm for pre-clinical safety [and] toxicity testing.”
At the center of FDA’s roadmap are certain “new approach methodologies” (NAMs) that would underpin such a transition. These NAMs include machine-learning and artificial intelligence (AI) predictive models, which can be used to analyze a drug or biologic’s active ingredients and structure and foresee potential adverse-event-causing toxicities. These may also be used to assess whether a compound could affect a part of the body that is not actively targeted. The roadmap also references “organs-on-chips,” where organoids produced from human cells are integrated with a bioengineered chip to create a controlled environment simulating that of the human body.
To facilitate the industry’s adoption of these NAMs, FDA plans to take a multifaceted policy approach that focuses on breaking down barriers to uptake and providing direct incentives for the industry. As one example of its barrier-breaking approach, FDA stated its intent to construct a large public database of toxicological data to allow machine-learning models to be more effectively trained. Such a database would be constructed in concert with other federal health agencies, such as the National Institutes of Health, and would leverage pre-existing international safety and toxicity data. To that end, FDA also announced its intent to waive the requirement that sponsors collect additional human data where the product has been approved in a foreign country with similar regulatory standards.
FDA’s roadmap also includes direct incentives, including faster approval times and reduced testing requirements, to encourage sponsors to use NAMs as part of their data-gathering methods. For example, the agency mentioned it hopes to encourage NAM adoption by fast-tracking regulator meetings and product reviews for INDs that use NAMs. FDA stated that it could reduce or altogether waive animal testing requirements in certain cases, such as where short-term animal testing raised no red flags and NAM trials are ongoing.
While the FDA roadmap primarily focuses on policy initiatives to encourage the industry’s move to NAMs, it also recognizes that key technical advancements and knowledge-building activities are required to ensure a smooth transition. In concert with its industry-focused initiatives, FDA intends to engage in measures such as gap analyses to determine where NAMs are best suited to replace or augment animal data. The agency also looks to invest in the development of NAMs by studying their costs and benefits in the preclinical context.
Through this synergistic approach, Commissioner Makary hopes to realize a “win-win for public health efforts” whereby the development of life-saving treatments is accelerated while animal testing is gradually phased out.
Next Steps
To implement the initiatives described in its roadmap, FDA plans to update existing guidance and issue new guidance clarifying its vision for the appropriate use of NAMs in drug and biologics development. FDA also plans to host a public workshop later this year to discuss the roadmap and aims to launch a pilot program allowing select monoclonal antibody developers to use a primarily non-animal-based testing strategy under close FDA consultation.
McDermott will continue to monitor any changes FDA makes to facilitate the adoption of NAMs in preclinical testing and analysis. If you have questions about how FDA’s roadmap could impact your business, please contact a member of McDermott’s Food, Drug & Medical Device Regulatory Group.
