Scientists and clinicians are racing against the clock for the development and clinical testing of coronavirus vaccines.
(Image by Angelo Esslinger from Pixabay)
As the number of confirmed COVID-19 cases is continuously on the rise, scientists across the world are toiling to develop a vaccine, which will help prevent the virus from infecting new people and eventually stop the pandemic.
However, SARS-CoV-2, the newly identified virus responsible for COVID-19, has already evolved into two genetically distinct strains. The initial “S-type” virus appears to be less infectious and causes milder symptoms, whereas the most recent “L-type” strain is far more infectious, accounting for approximately 70% of COVID-19 cases [1].
Two of the genetic changes between the “S” and “L” strains are found in a viral protein that is involved in the infection process. These infection proteins are usually targeted by vaccines, thus rendering the development of a coronavirus vaccine even more challenging.
The release of the genetic sequence of the SARS-CoV-2 genome shortly after the outbreak that started in December has been critical in accelerating the efforts for the development of vaccines and treatments alike. Several laboratories in research institutes and pharmaceutical companies around the world claim to have developed vaccines against coronavirus, which are currently being tested in animals.
The safety and efficacy of some of the potential vaccines will start being tested in human trials as early as next month. If successful, a coronavirus vaccine could be available early next year.
Moderna Therapeutics, CureVac, GlaxoSmithKline, Inovio Pharmaceuticals, Johnson & Johnson, and Sanofi, are among the companies currently racing to test their novel coronavirus vaccines at a preclinical or clinical stage.
“We have the kind of technology to be able to generate a vaccine with a speed that's never been realized before,” said Professor Robin Shattock from the Department of Infectious Disease at Imperial College London, who leads a team that has developed a candidate coronavirus vaccine. “Most vaccines are five years in the discovery phase, and at least one or two years to manufacture and get into trials,” he added [2].
Coalition for Epidemic Preparedness Innovations (CEPI), an international organization that provides financial aid to researchers trying to develop vaccines against epidemic viruses, announced that a vaccine for SARS-CoV-2 would be ready for human testing within the next two months.
However, the journey between a vaccine entering preclinical or clinical studies and the acquisition of regulatory approval for human use might be long and bumpy. Considering the severity and urgency of the situation, however, it is likely that this process might be accelerated.
In the light of the emergency of the situation, a clinical trial has already started recruiting participants in Seattle for the preliminary safety testing of an experimental coronavirus vaccine developed by Moderna Therapeutics, despite the fact that the vaccine has not been tested in animals first, as is typically required.
"I'm cautiously optimistic that we will get a vaccine," said Dr. Anthony Fauci, the National Institutes of Health's director for infectious diseases. "The thing that's sobering is that it's not a vaccine we're going to have next month, so we're going to have to tough it out through this evolution." [3]
Although it remains unclear what will come first –a coronavirus vaccine or the natural end of the outbreak, the new COVID-19 pandemic has fostered the advancement of technologies for diagnosis and vaccine development, which will allow for a robust response in future viral outbreaks.