A key tool in the fight against the COVID-19 pandemic that is currently holding the world hostage is a vaccine that would impart immunity against an infection caused by the SARS-CoV-2 virus, and the widespread distribution of such an agent may be necessary before the world can start getting back to a state of “normality.” But how far off is such a vital vaccine—and what might be the consequences of cutting corners in the mad rush to inoculate humanity in this unprecedented circumstance?
“Normality, as it was before, will not come back full-on until we get a vaccine for this… That will be a very long way off,” Canadian Prime Minister Justin Trudeau said in an address on April 9.
According to the World Health Organization, there are more than 70 vaccines for COVID-19 currently in development, with three of these candidates already having moved to human trials. The organizations racing to produce the vital treatment span a broad range, from small biotech companies to big pharmaceutical corporations, academic institutions and nonprofit entities.
Chinese biotech company CanSino has already moved their vaccine candidate to Phase 2 clinical trials; in the US, biotech startups Inovio Pharmaceuticals and Moderna have begun Phase 1 human testing, and large corporations, including Johnson & Johnson and Sanofi, are also racing to develop their own vaccines.
Typically, all five phases of a clinical trial are part of a lengthy development process that typically takes years to properly unfold; the virulence and relative lethality of the coronavirus that is causing the current pandemic, however, has necessitated that the organizations involved put an unprecedented amount of haste into their efforts. But even with development of a new vaccine kicked into high gear, it could still take some time for a safe and effective vaccine to be ready for distribution.
Health experts are concerned that in the rush to get the vaccine out the door, vital corners might be cut in the process: typically, new drugs are first tested “in vitro” (lab-tested outside of a living organism), then in animals before they’re applied to human test subjects; skipping any of these steps, as biotech company Moderna is reportedly doing, could cause the vaccine to backfire and cause an effect known as “immune enhancement,” a situation in which a vaccine winds up weakening the patient’s response to the virus.
“The way you reduce that risk is first you show it does not occur in laboratory animals,” according to Dr. Peter Hotez, the dean of the National School of Tropical Medicine at Baylor College of Medicine. “I understand the importance of accelerating timelines for vaccines in general, but from everything I know, this is not the vaccine to be doing it with.”