The current leadership of the US National Institutes of Health (NIH) has a stated goal of de-emphasizing the use of animal models in health-related research with the rationale questioning “the effectiveness of translating findings from animal models to human diseases, such as Alzheimer’s disease and cancer,” arguing that “these translational challenges faced by humans may be due to differences in anatomy, physiology, human lifespan, and disease characteristics” (National Institutes of Health press releaseApril 2025). This formal statement was followed several months later by an announcement clarifying that the NIH “will no longer develop new funding opportunities focused exclusively on animal models of human disease” (National Institutes of Health press releaseJuly 2025).
It is true that therapeutic translation from laboratory mice – the backbone of mammalian biomedical research – to humans for the treatment of many age-related diseases has been poor. For example, more than 300 interventions have shown some success in ameliorating disease or improving behavioral symptoms in mouse models of Alzheimer’s disease, but few have demonstrated safety and efficacy in humans.1. Likewise, although the majority of the more than 1,000 acute stroke treatments evaluated in laboratory rodents have had significant therapeutic benefits, almost all have failed in human trials.2. In cancer research, only about 8% of successful animal experiments make it to the clinic3. This high failure rate, and the associated cost in terms of time and money, makes it understandable that the benefits of animal research are subject to scrutiny.
