How close are we to a coronavirus vaccine?

Millions of dollars and hundreds of hours of researchers’ time have been invested in the hunt for a vaccine for the novel coronavirus.

It’s paying off – experts say we could see the first vaccines approved by the end of 2020, but there’s still a lot of questions that need to be answered before you roll up your sleeve. These include how well it works, which shot we use, and who gets first crack at the new vaccine.

Where research stands

In late July, some manufacturers announced promising early results. A vaccine candidate developed by researchers at Oxford University in the U.K. appeared to cause an immune response with minimal side effects. A joint Canadian and Chinese project also announced that they were moving forward with further testing, after seeing some success.

According to the World Health Organization, there are currently 165 vaccine candidates being studied worldwide. Five of those are in Stage 3 clinical trials – typically the last stage, after which the vaccine could be approved if it shows positive results.

One of those, by the company Moderna, is now being tested in thousands of people across the U.S., in a trial that started Monday.

“I think it’s pretty exciting that a number of vaccines have moved on to this phase,” said Dr. Manish Sadarangani, an assistant professor at the University of British Columbia and director of the Vaccine Evaluation Centre at B.C. Children’s Hospital.

“I think it’s actually incredible to think that, given that normally vaccine development takes 10 to 15 years at least, that we’ve done several years’ worth of development in the space of a few months.”

Manufacturers were able to move so quickly in part because they’re building upon other vaccines, he said. “It’s not quite plug-and-play,” he said, but manufacturers were able to take existing vaccines and swap out a few pieces to try to match them to the SARS-CoV-2 virus rather than starting from scratch.

Dr. Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, told Congress Friday that he’s hoping for one or two successful vaccines by late fall or early winter.

2:30 Coronavirus: Dr. Fauci says multiple COVID-19 vaccine candidates are moving at ‘very rapid pace’

While some experts have said it will take longer, others like Craig Jenne, an associate professor in microbiology, immunology and infectious diseases at the University of Calgary, believe it’s possible.

“I do believe that we will see one and maybe even two vaccines approved both by the FDA and by the European Regulatory Agency before the end of the calendar year,” he said.

“That doesn’t mean that January 1st we can get vaccinated.”

Safe and effective

Health Canada will want to review safety data itself and approve a vaccine on its own judgment, rather than just applying “a rubber stamp” to whatever the U.S. approves, Jenne said. This will take some time.

Sadarangani doesn’t believe there is any reason to be concerned about the speed of the research. “I think, to be honest, the follow up of participants in the trials has been very rigorous. These are people who are followed up very closely to look for side effects,” he said.

7:09 How close are we to developing a coronavirus vaccine?

COVID-19 vaccines will still have to provide safety and efficacy data the same way as any other vaccine in order to be approved, he said. This includes monitoring for side effects even after it hits the market, as there might be very specific groups of people who experience side effects from the shot, which weren’t identified in trials.

The vaccine won’t necessarily be 100 per cent effective in preventing COVID-19 either.

“The WHO has set the bar at 50 per cent,” said Dr. Brian Ward, an infectious diseases professor at Montreal’s McGill University and medical director of Medicago, a Canadian vaccine manufacturer that is working on its own vaccine candidate.

“A vaccine that is 50 per cent effective will be considered a good enough vaccine to move forward.”

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The measles vaccine, considered an extremely effective vaccine, is about 97 per cent effective with two doses, the CDC says. The flu shot varies between 40 to 60 per cent.

Even a partially effective vaccine would allow us to get back to something closer to pre-pandemic life, Ward said. There’s another advantage too: it’s likely that even if the shot doesn’t fully protect someone, it will still drastically cut down the chance of severe illness if they do catch the virus.

This happens with the flu shot, he said, where your symptoms are likely reduced, even if it doesn’t always keep you from catching the flu. “If we can reduce SARS coronavirus to being like the other human coronaviruses where it’s like a cold, that would also be certainly good enough.”

Getting the shot

Even after a shot is approved, it could still take a while before it’s generally available, experts say.

First of all, there are likely to be several vaccine formulations that get approved, said Jenne, who also holds a Canada Research Chair.

“As an immunologist, I very much hope that we get more than one answer,” he said.

Having several different vaccines would be a good thing, he said, as some might be more suited to give to vulnerable populations like people with pre-existing conditions or the elderly. It’s also possible that an individual might be able to get even better immunity by taking several shots.

The other reason we need many different vaccines approved worldwide, or at least made worldwide, comes down to manufacturing capacity, Ward said.

“Almost all of the vaccines that are in clinical trials are testing two doses, and most of them are likely to need two doses based on animal data to date. So that means that if we’re going to vaccinate the world at 7.8 billion people, we’re going to need 15.6 billion doses of vaccine.”

Even the pharmaceutical giants are only talking about producing 500 million doses per year, meaning it would take years to vaccinate everyone unless there are many different vaccines being made, he said.

4:37 Why hasn’t Canada pre-ordered a COVID-19 vaccine?

Some countries, such as the U.S., have already made deals with pharmaceutical companies to secure supplies of an eventual vaccine, leaving smaller countries like Canada further down the list.

“If you’re talking about trying to vaccinate huge numbers of people across the globe, then I think the timeline is going to be a bit longer,” Sadarangani said.

“I don’t think it’s going to be a one-off: suddenly there’s a vaccine and everyone’s going go and get it the next week.

“I think it’s going to be a sequential thing where there’s decisions that need to be made about how to prioritize the use of the vaccines, and who should get the vaccine first, who’s at the highest risk of getting severe disease. And then who gets it in subsequent production batches.”