Animal testing isn’t our only option — NIH needs to invest in alternatives

As the COVID-19 pandemic pushes 25 million cases worldwide and 6 million cases in the United States, researchers, clinicians, and public health experts continue to race to uncover clues about this deadly disease. We know what’s at stake. We know we need to take swift and bold action to bring the virus under control and protect ourselves and loved ones from this horrific and deadly illness.

COVID-19 is in some ways bringing the world together in a collective spirit, helping us realize that individual action such as mask-wearing has a protective ripple effect throughout our communities. But it is also tearing us apart. Stay-at-home orders, while necessary to “flatten the curve,” at best still result in feelings of loneliness and isolation, and at worst draw racial and socioeconomic lines that protect some and deem others “essential.” Black and Latino Americans are experiencing the disease at higher rates than white Americans. And the response to COVID-19 demonstrates a stark partisan divide. 

Taming COVID-19 is an urgent imperative, and future pandemics are bound to occur. We have a great deal to learn, and the National Institutes of Health (NIH) is heeding this charge. But there is lost opportunity when we travel down one path instead of another when we fund one sort of research over another when we opt for the familiar but insufficient instead of the relatively new but promising when we prioritize animal research over research methods that put the human immune system, the human respiratory system, and human physiology in focus. 

Clearly, we have a long way to go. There are still no vaccines approved for full use, although 125 are currently being tested in clinical trials and preclinical stages. COVID-19 is a deeply varied disease in terms of an immune response, clinical presentation, and socio-demographic factors associated with prevalence, making it difficult to study, understand, and treat. There is no silver bullet. We need to tackle this challenge from multiple angles. 

Biomedical research creates a foundation for every strategy to curb the virus, from the development of vaccines and treatments to medical protocols and public health measures. Accordingly, Congress has so-far allocated nearly $3.6 billion of emergency supplemental funding for COVID-19 research to the NIH, including over $1.5 billion to the National Institute of Allergy and Infectious Disease (NIAID), the NIH institute leading the agency’s charge for basic research investigating the disease’s causes and pathogenesis. And on Thursday, the NIH announced the establishment of Centers for Research in Emerging Infectious Diseases (CREID), a network of institutions and investigators from all over the world that will focus on how and where viruses and other pathogens emerge and cause disease in people. However small, with just $17 million provided for the first year, this network is a step in the right direction for infectious disease research and pandemic preparedness.

In its announcement, the NIH states that CREID investigators will “study human immune responses to new or emerging infectious agents.” So why, then, is the Washington University in St. Louis Center planning to develop mouse models of infection and ferret models of transmission? This is a part of a larger pattern of the NIH prioritizing the use of animals to model diseases instead of investing in the development and use of human-relevant approaches like tissue chips and organoids. These technologies replicate the structure and function of human organs and tissues and are powerful approaches for studying human infectious disease pathology and transmission and can be used to develop and test new drugs and vaccines.

In April, NIAID released a Strategic Plan for COVID-19 Research, which details the institute’s strategic research priorities, including improving fundamental knowledge of COVID-19 and the virus that causes it, SARS-CoV-2. It’s aiming to do this by pursuing the development of small and large animal models that attempt to replicate SARS-CoV-2 pathogenesis in humans, despite its own admission that, “Previous experience with related coronavirus diseases such as MERS and SARS suggests that replicating human disease, particularly its more severe manifestations, in an animal model may be challenging.”

Vaccines for SARS and MERS never came to fruition. The challenge of using animals to model coronavirus infection in humans contributed to this failure. As with these previous coronavirus diseases, most animals used to study COVID-19 are either not susceptible, present with no illness, milder symptoms, or differing symptoms from humans, have differing immune responses, or cannot capture the complex web of disease risk tangled up with racial and economic factors and underlying conditions.

Animal research is not our only option. Robust, innovative nonanimal basic research strategies are currently being employed to some extent at the NIH: The National Center for Advancing Translational Sciences is aiming to speed COVID-19 translation by investing in human-relevant tools like 3D bioprinting, tissue chips, and high throughput screening assays for drug discovery. 

The NIH must expand these efforts, not just for COVID-19 but also in its larger infectious disease research portfolio and its newly-formed CREID network. We cannot afford more of the same ineffective strategies. We cannot afford more needless suffering. The NIH must act now. 

Catharine E. Krebs, Ph.D., is a medical research specialist with the Physicians Committee for Responsible Medicine