The US Food and Drug Administration (FDA) has announced plans to begin replacing animal testing in drug development with “more effective, human-relevant methods”, including AI models and lab-based systems like organ-on-a-chip.
The shift is grounded by the 2022 FDA Modernization Act, which for the first time authorised the use of non-animal alternatives in preclinical testing.
The FDA said the new framework, initially targeting monoclonal antibodies (mAbs), aims to enhance drug safety, as well as reduce R&D costs and drug prices. mAbs form the backbone of many cancer, autoimmune, and infectious disease therapies.
Under the plan, developers of investigational new drugs (INDs) are encouraged to submit data from new approach methodologies, which include computational models, organ-on-a-chip systems, and other advanced in vitro platforms.
The agency will also begin accepting real-world safety data from countries with comparable regulatory standards, allowing it to assess previously studied drugs without repeating animal trials. While the timeline for full implementation remains unclear, the FDA said immediate changes would apply to IND submissions. A pilot programme will launch in the coming year, offering selected mAb developers the opportunity to use a primarily non-animal-based testing strategy under FDA oversight.
FDA Commissioner Martin Makay called the move “a paradigm shift in drug evaluation” that could accelerate access to treatments while improving animal welfare.
William Blair analysts described the announcement as “a statement of intent” rather than a binding regulatory overhaul. They noted that while the 2022 legislation allowed for non-animal testing, it did not commit to reducing or eliminating animal use.
“We expect these changes to be rolled out gradually over time and believe drug developers will still want to do at least some animal testing,” the analysts wrote.
They flagged Charles River Laboratories – which derives around 20% of its revenue from non-human primate testing – as vulnerable. The company’s shares dropped 28% following the news. In contrast, William Blair views the development as a long-term tailwind for Certara and Simulations Plus, which offer AI-driven and in silico preclinical models.
Outside of regulatory circles, the announcement has drawn attention across the scientific community. Medical sciences professional Paniz Farshadyeganeh on LinkedIn said: “Animal testing has long been a necessary—but often cruel and poorly regulated—part of research. With advances in patient-derived iPSCs and organ-on-a-chip technologies, we now have the potential to build better, more human-relevant models.”
Organ-on-chip technologies have gained traction as new tools for studying human disease, with newer developments such as tumour-on-chip models enabling cancer drug screening. Last month, researchers from Heinrich Heine University Düsseldorf and biotech firm Dynamic42 created a pancreatic cancer chip model, which showed promising results in testing MSD’s FDA-approved therapy Zolinza (vorinostat).
In parallel, simulation cell technologies are gaining momentum. AstraZeneca, in partnership with biological simulation company Turbine, has been using AI-driven models of cancer cells to predict drug resistance mechanisms and identify viable combination therapies in blood cancers.
