(This essay is the latest in our continuing series about the relationship between animal-use industries, pathogens, and animal and human health.)
COVID-19 has infected 1.5 million people, with that number to swell before the virus’s person-to-person global hopscotching pauses. In response, scientists in laboratories are racing to develop a vaccine and therapies to arrest its progress and to palliate its worst effects.
But the race between the scientists and the virus is rigged. The virus had its usual head start, after jumping the species barrier at a “wet market” in Wuhan. But our regulatory system, and our scientific method, is so cumbersome that the virus has been sprinting farther ahead. It is, in practical terms, lapping us.
The reason is apparent: the U.S. and European government agencies that regulate drug development — led by our own Food and Drug Administration (FDA) — have an outdated “check-the-box” policy for testing the safety and efficacy of new drugs. That process is slow, too regimented, and predictably imprecise. Regulatory requirements dictate the use of animal testing in the initial round of inquiry even if the animals cannot show symptoms or experience the onset of disease.
The result is, the process typically takes drug makers ten years to bring a vaccine or treatment drug to market. Animal testing drags out the timeline as scientist are required to examine the drug’s effect on multiple generations of multiple species of animals.
The results are often hardly worth the wait. More than 90 percent of drugs that pass animal tests for safety and efficacy fail in human trials. Even after years of training and success in scrimmages, a quarterback would be benched in no time if he completed just 10 percent of his passes in the real game. The same in baseball, where a hitter is expected to connect and get on base at least two or three times out of 10. But in laboratory animal testing, we have normalized and excused this massive failure rate.
These delays and faulty results cause suffering patients to languish or die.
Here’s one reason why the results are so bad: Animals often are poor models for disease. Typical lab mice, for example, are not susceptible to COVID-19. But that doesn’t stop researchers from attempting to genetically modify mice with human molecules to increase their susceptibility. Researchers are even going into their freezers to thaw out SARS-infected mice embryos and sperm to engineer a mouse model (even as many institutions issue orders to “cull their colonies” because animal caretakers are not able to work).
Yet they might want to rethink their medical grave-digging. Researchers were completely unsuccessful in developing vaccines or therapies for two prior disease epidemics — SARS in 2003 and MERS in 2012. That’s right — no vaccine for either virus.
So, today, the world waits to see how fast a “Franken-mouse” can be bred, ifthe animal is susceptible to COVID-19, if the animal shows signs of disease, if the animal shows an immune system response, and if the animal data translates to human clinical trials.
FDA tells researchers it must use rodents and also non-rodents. And that’s why they are scrambling to find other species of animals for testing COVID-19 medications — doubling the risks and the body count for animals. That means hamsters, marmosets, macaques and African green monkeys are being infected in the faint hope something will work. Ferrets are being tranquilized so they don’t sneeze when COVID-19 is squirted into their nostrils.
Yet even if an animal is susceptible to the virus, they may not exhibit signs of disease. That was the case with chimpanzees in our rightly frenetic efforts to develop a vaccine against AIDS. Years later, researchers themselves said that chimpanzees were an ineffective model and a resource drain in their efforts to find a cure. Eventually, after millions of humans died after experimenting on chimps and not discovering treatment options, researchers found other pathways for developing the therapies that now afford people with AIDS a normal life expectancy.
Throwing a Hail Mary pass — in other words, trying a series of animal models when the odds of success are so remote — is not, at the very least, something that should be required in every circumstance. It is a scientific reflex, wasting finite resources and eating up the bandwidth of capable scientists.
There are non-animal, human-relevant test methods that provide us with better options. Last month, in recognition that an urgent crisis like this one requires flexibility, some researchers got the go-ahead, including at the labs of the drugmaker Moderna, to start clinical trials prior to completing animal tests. That’s no revolution, but it is progress.
One of the most promising replacements for animal testing is Organ-on-a-Chip technology. Imagine a marriage between a petri dish and microchip. These highly engineered microfluidic devices are lined with human cells and can simulate the mechanics of an entire organ. Harvard’s Wyss Institute has developed a COVID-19 disease model to use with the Lung-on-a-Chip, which prior work had shown could be infected by a virus. Wyss is employing this advanced technology to identify existing FDA-approved drugs and novel compounds that can be tested in the Organ Chip-based COVID-19 therapeutic repurposing pipeline. This technology may be used to identify therapeutics, or as prophylactic therapies for healthcare workers or patients who are particularly vulnerable to this disease.
The Johns Hopkins Center for Alternatives to Animal Testing has recently redirected part of its grant program to speed the discovery of medicines and vaccines for COVID-19. Its goal is to stimulate funding and centralize information for development of human-relevant models to accelerate response to the coronavirus crisis.
Human beings inadvertently gave a global launch to COVID-19 by mistreating animals in “wet markets” in China. We compound the injury to animals by requiring their use to combat a virus of our own making, especially when that pathway is very unlikely to yield a positive outcome. We can do better, but it means breaking free of outdated requirements and intellectual straitjackets, and pursuing the best, fastest, most innovative science we can muster.
Wayne Pacelle is president of Animal Wellness Action, and Tamara Drake is Director of Research and Regulatory Policy for the Center for Responsible Science