Scientists may need to "take the brakes off" in their quest to produce an Ebola vaccine, which is already being fast-tracked through the regular phases and processes, but may still be at least a year or more away from mass trials.
"I really hope we can do it faster and given the pace that I see things moving at now, it is possible that we will go even faster. It really depends on how hot the fire is turned in Africa," said Brian Ward, a microbiology associate professor at McGill University's Centre for the Study of Host Resistance.
"If that burner goes full on and we really do see some of these predictions of 10,000 cases a week, I think that many people, including me, would start to argue to hell with this... we may just need to take the brakes off and just take a chance."
Although Ward was one of the scientists who looked over the protocol development plan for the Ebola vaccine trials, he is not directly involved in them.
So far, more than 8,900 people have been infected and more than 4,400 have died, mostly in Guinea, Liberia and Sierra Leone.
Earlier this week, federal Health Minister Rona Ambrose announced that phase one clinical trials of the Ebola vaccine VSV-EBOV, which was developed at the Public Health of Canada's National Microbiology Laboratory, will begin on a small group of healthy people to assess its safety, determine the appropriate dosage and identify any side effects.
The outcomes of the Phase 1 trials, being conducted at the Walter Reed Army Institute of Research in Silver Spring, Md., are expected in December 2014. That's unusually fast.
'Leapfrogged' by at least a year
Typically, Phase 1 studies, in which the vaccine is injected into healthy human specimens, can take up to a year, Ward said.
"We've leapfrogged probably by at least a year because we've massively compressed the toxicity studies and we have massively compressed the regulatory review."
Even before scientists began Phase 1, they had to complete a protocol development plan, a process that can take a couple months, (and several more months to be approved by a regulator). That whole process was fast-tracked for the Ebola vaccine and completed in a matter of days, Ward said.
Health Minister Rona Ambrose announced that an experimental Canadian-made Ebola vaccine will begin clinical trials in what officials are calling a promising development in the fight against the deadly disease. (Sean Kilpatrick/Canadian Press)
In the Phase 2 stage, researchers study the effects of different dosages, expand the testing pool to several hundred people — a process that could take up to two years. That phase for the Ebola vaccine will likely be compressed to about six months, Ward said.
By Phase 3, scientists look for efficacy, to see if the vaccine actually works under field conditions and may involve upwards of 80,000 people. In normal vaccine trials, that study can also take several years, meaning by the time phase three is completed, it could be five or even 10 years before a vaccine is ready for mass production.
For the Ebola vaccine, phase three trials would also be compressed into about six months, Ward said. Still, even with all the condensed phases and trials, an Ebola vaccine ready for phase three or for mass population could still be more than a year away.
'Willing to take a pretty high risk'
"This is the question I answered for Public Health Agency of Canada ... How fast can you actually do this? And it really depends upon how much risk you're willing to take. And obviously in the case of the people living in the Ebola affected countries, you're willing to take a pretty high risk," says Ward.
But the compelling reason to move so quickly is that this is the only chance scientists have to shut this virus down, Ward said.
"We're rushing it…because the potential consequences for west African society are apocalyptic," he said.
"Right now, as you can see, the temperature is being ratcheted up every week, we are seeing near exponential growth in the number of cases," he said. "And how high can that temperature go before we just say 'to hell with this, we're going to manufacture a whole whackload of this stuff and just pray that it works."
But Ward cautioned that there is plenty of risk in rushing a vaccine into production, and that there is a potential for fatalities, particularly on a population where many are HIV-infected, immuno-compromised or malnourished.
"As a medical scientist, it scares me to death. I'm well aware of the damage that could be done, aside from the lives that could be lost. I'm aware of the damage that could be done to the whole vaccine enterprise."
But Jason Tetro, a microbiologist and author of The Germ Code, said he hopes the timeline for a vaccine will move along much faster and he hopes that by this time next year, scientists will have produced enough vaccine for all people who are potentially at risk.
"Then by 2016, the whole concept of the epidemic will be gone and by 2017, we'll have enough coverage so that this particular virus will never start an epidemic again," he said.
But Tetro said the current epidemic still needs to be stopped at the base with the current tools of containment, beds, bricks and mortar, health-care workers, and all available treatment options.
"The vaccine is not for this epidemic it's to prevent future ones," he said.
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