The U.S. Food and Drug Administration (FDA) announced it intends to begin phasing out animal studies for preclinical data packages of monoclonal antibody (mAbs) drug candidates. Regulators are confident that modern and emerging solutions – including biosimulation, predictive analytics, and organ-on-a-chip tools – can replace data typically collected from dosing mAbs in mice and other rodents, dogs, and non-human primates (NHPs).

Although phase-out guidance wasn't given for other types of therapeutics, kicking off the modernization effort with mAbs makes sense. As of the end of 2024, the FDA had approved 180 mAbs across therapeutic areas ranging from immunology to oncology. There are over 2,000 active clinical trials, which promise to lift the therapeutic modality's commercial potential beyond the $250 billion in global revenue generated in 2024.

In other words, scientists have reams of data to be reasonably sure we can quantitatively predict pharmacodynamic, pharmacokinetic, and other important metrics for mAbs without animal studies. Just to be sure, the FDA will require participating companies to submit investigational new drug (IND) applications that include both modern solutions and animal studies. If the comparisons hold up, then regulators will fully phase out animal studies for preclinical work in mAb drug candidates.

It won't be possible to eliminate all animal studies, especially for new therapeutic modalities that cannot be accurately modeled with biosimulation tools. But the modernization effort could spare millions of research animals each year.

For example, Novo Nordisk has purchased an average of 61,147 animals per year for the last decade. The overwhelming majority (>96%) are mice, rats, and other rodents. But the world's second-largest drug developer for cardiometabolic diseases still purchases thousands of pigs, rabbits, dogs, and NHPs each year.

Unfortunately for Norway's lab animal residents, Novo Nordisk only has four mAb drug candidates in development.