As the novel coronavirus (Covid-19) cases rise all over the world, scientists are racing to develop a vaccine to contain its spread. However, there are varying reports about when a vaccine could be ready.
Normally, developing a vaccine against a disease takes several years due to lengthy clinical trials and strict regulatory approvals.
That said, according to Dr Erich Tauber, CEO of the Vienna based Themis Bioscience which specialises in vaccine development, given the rapid spread of Sars-Cov-2 and the damage it has inflicted all over the world, a vaccine against Covid-19 could get rapid approval as an emergency measure very soon.
There is a caveat, though. In vaccine research and development, rapidly means in a year’s time and not soon enough for this outbreak.
Themis Bioscience, in collaboration with the Pasteur Institute recently initiated the development of a vaccine candidate against Covid19. This is a joint project and there is number of research teams around the world that are already part of this project.
Development of vaccines is slow. Another Themis Bioscience vaccine, this one against Chikungunya, has reached a much advanced stage of Phase III trials. Dr Tauber says their Chikungunya vaccine, which has been under development for the past seven years, will be ready by 2023.
Typically, the Phase III trials involve testing the vaccine on several tens of thousands of people. But to reach this stage, the vaccine makers have to clear many hurdles.
How to develop a vaccine?
According to Dr Maxime Schwartz, former director of the Pasteur Institute, the first couple of steps of vaccine creation may be fairly quick.
“Once you have identified a new virus, you grow it on cells. Then you can kill the virus or find a molecule from the virus and inoculate animals with either of the two to see if it induces immunity. Once you have a positive result from the animal testing, you go to the next stage which can take a very long time,” she said.
This is when the vaccine gets tested in humans in three phases. Schwartz explains that the first step involves needing a few human volunteers to check the kind of immunity it induces and to check for any adverse effects.
“What is much more difficult is to see whether it really protects people. In order to make sure, you have to test it on a large population in places where there is a great risk of contracting the disease. In such places, you have to vaccinate some of the people and not vaccinate others to see what the difference is,” she added.
He adds that the other difficult part is to ensure its complete efficacy.
“In order to make sure there are no adverse effects, you must test it on a very large number of people, perhaps several tens of thousands of people, because if you have a vaccine that, let’s say, protects 1000 people but kills one then it’s a big problem. This can take several months or years. However, in cases of emergency, this step may be somewhat shortened,” he says.
For his part, Tauber reckons the development of the Covid-19 vaccine could be accelerated due to the emergency situation we are currently facing.
“Because of the devastating impact of Covid-19, all the stakeholders, from companies to regulatory agencies, will act faster and a vaccine could be on the market next year. A precedent was set in the case of the H1N1 flu when these timelines were accelerated,” he says.
He also says that compared to diseases like dengue or ebola, it will be r easier to develop a vaccine against the novel coronavirus.
“People know exactly what antigens will be required. Since this virus is very closely related to the Sars and Mers viruses, people have a very good understanding on how to make this vaccine.”
However, Tauber has a word of caution.
“This fast-track approach needs to be done with care because when you vaccinate people it’s exactly the opposite of treating someone. That’s because a perfectly healthy person gets vaccinated,” he said.
So one needs to make sure that the risk in getting vaccinated is substantially smaller than the risk of the disease. In short, there should be no side effects or it should be avoided as much as possible,” he says.
One way or the other, whatever happens a new vaccine will not be ready in the coming weeks.