The development of COVID-19 vaccine explained

Finding a vaccine for the coronavirus disease 2019 (COVID-19) is the toughest challenge the scientific world is facing amid the pandemic. How long does it really take for a vaccine to be developed?

According to a report on GMA News Digital, it took scientists four years to develop a vaccine for the mumps virus, which is actually the fastest vaccine to have been developed in history.

In 1967, Maurice Hilleman developed the approved  mumps vaccine after four years of development from getting samples, approval, and finally to its licensing.

"Being optimistic, I think we will probably have some vaccine in 18 months from start, so probably sometime mid-next year. So 14 months from that, that would be a very optimistic view," said Dr. Lynda Stuart, tth director of vaccine research at the Bill and Melinda Gates Foundation.

Bill and Melinda Gates Foundation is the biggest charity helping scientists find a vaccine for COVID-19.

The development of a vaccine

In developing a vaccine, Stuart said there are two things to consider: speed and volume.

“So I think there are two problems that we face with vaccines for COVID-19. The first is clearly we would all like a vaccine very quickly. And so there is a question of speed. But the second question is a question of volume.” 

Stuart said speed of vaccine development and the volume of mass production must be balanced, since one without the other will not give the world the right solution.

"If we get a vaccine that's very fast, but we only can give it to 10 people that's not going to help us," Stuart explained.

"And if we get a vaccine that we can give to millions of people, but it takes us 10 years, that's also not the right solution," she added.

Stuart said for the planet to return to normalcy, a COVID-19 vaccine has to be developed.

“How long it will take us to get the first vaccine is very different from how long will it take us to get a vaccine that we can deploy to 7 billion people on the planet," Stuart said.

Although vaccine development has been a difficult challenge for science experts, a new technology and the unprecedented global collaboration within the scientific community can help speed up the process.

"The global scientific community has been quite remarkably collaborative... There are probably about 80 or so or between 80 and 100 labs that are beginning to work on this.”

“[To] get to this point would take us a couple of years. So the fact that we're here in a couple of months is, I think the important thing to know," she added.

It also helped that the genetic sequence of SARS-COV-2 or the virus that causes COVID-19 has also been released early.

According to the report, knowing the genetic sequence is important for experts to learn the characteristics of the virus including its behavior and weaknesses. This will help them produce vaccines and cure.

How does the vaccine work?

Professor Marilen Parungao who teaches microbiology at the University of the Philippines-Manila and who is also studying vaccinology explained how the vaccines work with an interesting metaphor: A by-invitation-only party, where the virus the gate crashers.

“Imagine there’s a by-invite only party. Those who don’t have an invitation will be stopped by the bouncer from entering. That’s how vaccines work in our body. They stop the gate crashers," she said.

“If a foreign body enters your system, your immune system will detect it and say, ‘You don’t belong here.’ Then, it will find a way to protect your body, in case the intruder does something harmful," she added.

"Have I seen him before? Have I met him before? What did I do when I met him? That’s how our immune system works.” 

The phases of vaccine development

Parungao said developing a vaccine is no easy and fast work since the experts need to allot time to study it thoroughly.

“It’s not like you can just develop vaccines in a snap. Like, when you wake up, there’s a vaccine already," Parungao said.

According to Parungao, development of vaccines goes through different phases before it gets approved and distributed to the public.

The first is the exploratory phase where experts study the virus to be able to devise the correct strategy to defeat it.

“It’s like what they are doing with COVID-19. They are studying its genome to know the characteristics of the virus," she said.

The second one is the pre-clinical phase, where laboratories check the effectiveness of the candidate vaccine.

“They will mimic the inner workings of the body and then try to determine the reaction of the cell," Parungao explained.

"For example, will this candidate vaccine create a molecule that will say, ‘hey, did you create antibodies or not?’ If that didn’t happen, that means the candidate vaccine is not effective. Next!” she added.

If the candidate vaccine passes the clinical phase, it will then be tested via clinical trial in humans where it will try to determine three things: immunogenicity, efficacy, and most importantly, safety.

“Are you familiar with allergies? When you inhale dust, for instance, and then you sneeze or get itchy, that means your body identifies the dust as a foreign intruder," Parungao explained. "That is an immunogenic candidate. That’s good because your body recognizes it as something foreign.”

Effectiveness is the next thing to be determined or whether or not the candidate vaccine will produce anti-bodies to help beat a virus.

"You just don’t produce anti-bodies, it must help you clear the virus and cure you. That’s what we call efficacy.”

The most important element of vaccine development is safety.

Parungao said even if a candidate is effective but if it is proven unsafe, people can't use it and scientists have to go back to square one.

"This is what slows down the clinical trials. They would be in Phase 1 already of the trial and the candidate vaccine is not safe to use… They have to go back to square one," Parungao explained.

After experts declare a candidate vaccine's safety and efficacy, it will still be subjected to regulatory approval from the Food and Drug Administration or FDA.

Stuart said the experts are looking for ways to fast track it and have already started safety trials.

“The first safety trials I think started in March or April. So that's two or three months, rather than a year. So we're starting them really fast.”

Stuart said they are also starting to build the manufacturing capacity early to avoid a long period of waiting before it can be deliverable.

"And then we are also looking to do what we call at risk manufacturing scale-up. We know that once a vaccine works, we normally then have to build the factory that makes the vaccine," Stuart said.

"And so what we are doing is we're really trying to identify the ones that we think have promise and start building the manufacturing capacity early. So that if they work, we're not waiting a long period of time before the vaccine is actually deliverable in the billions of millions of doses.”

How much will it cost to make a vaccine?

According to the American Journal of Public Health, vaccine development costs US$200 million to US$500 million.

This is the reason why big pharmaceutical companies are mostly the ones capable of producing vaccines while independent scientists depend on monetary support from private institutions and the government.

Parungao said the best way to go about it is to fund the research and not offer a reward after producing one.

“Instead of telling people that they will get a reward for finding a vaccine, give them the money to actually start and fund the development process," she said."That would be a better quotation, instead of giving the reward at the end. What is that anyway? A reimbursement?”

“Science is not like that. Science is funded from the basic to the applied," she continued.

Should the day come when the world finally has the COVID-19 vaccine, Parungao said there should be a discussion on who gets access to it and reassurance that the poor will also receive them as well.

“For example, if the Philippines get an allotment, will it be shouldered, say, by the Philhealth, because not everyone can afford a vaccine?” — Jannielyn Ann Bigtas/LA, GMA News