COVID-19 vaccine: Human trials start globally, but still no guarantee
Hundreds of people are rolling up their sleeves in countries across the world to be injected with experimental vaccines that might stop COVID-19, spurring hope maybe unrealistic that an end to the pandemic may arrive sooner than anticipated.
Hundreds of people are rolling up their sleeves in countries across the world to get injected with experimental vaccines that might provide a cure for COVID-19, spurring hope that an end to the pandemic may arrive sooner than anticipated.
About 100 research groups are pursuing vaccines with nearly a dozen in early stages of human trials. It’s a crowded field, but researchers say this only increases the odds that a few might overcome the many obstacles that remain.
“We’re not really in a competition against each other. We’re in a race against a pandemic virus, and we really need as many players in that race as possible,” Dr. Andrew Pollard, who is leading the University of Oxford’s vaccine study, told The Associated Press.
The hard truth: There’s no way to predict which, if any, vaccine will work safely, or even to name a front-runner.
As Dr. Anthony Fauci, the US government’s top expert, put it: “You need more shots on goal for a chance at getting a safe and effective vaccine.”
According to the Dr. David Nabarro, a professor of global health at the Imperial College, London, “There are some viruses that we still do not have vaccines against.”
While speaking to CNN, he said, “We can’t make an absolute assumption that a vaccine will appear at all, or if it does appear, whether it will pass all the tests of efficacy and safety.”
The first cautious tests of March, when small numbers of volunteers got injections to check for side effects, have turned into larger studies in China, the US and Europe to look for hints that different vaccine candidates really protect.
Next: Finding out for sure if any of the vaccines work in the real world by testing large groups of people in areas where the virus is circulating – a tricky prospect when study participants may be in places where the virus is fading or they are told to stay home – and finding a way to quickly distribute lots of doses of any successful candidates.
Policymakers are devising plans to try overcome both the obstacles in an attempt to compress the years it usually takes to develop a vaccine.
Vaccine by January 2021
Asked if a vaccine by January was possible, Dr. Deborah Birx, the White House coronavirus task force coordinator, told Fox News, “On paper, its possible. It’s whether we can execute.”
Fauci has cautioned that even if everything goes perfectly, 12 to 18 months to develop a vaccine would set a speed record and January will mark a year since the National Institutes of Health began creating its own COVID-19 vaccine, now in trials with Moderna Inc.
Depending on how you count, there are between eight and 11 vaccine candidates in early stages of testing in China, the US, Britain and Germany. A collaboration between Pfizer Inc. and BioNTech began a study, last week, in Germany that’s simultaneously testing four somewhat different shots.
Nabarro, who also serves as a special envoy to the World Health Organization (WHO) on COVID-19, said the process of developing a vaccine could be slow and painful. “You have high hopes, and then your hopes are dashed. We’re dealing with biological systems, we’re not dealing with mechanical systems. It really depends so much on how the body reacts,” he said.
Concurring with the idea, Dr Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston, told CNN, “We’ve never accelerated a vaccine in a year to 18 months. It doesn’t mean it’s impossible, but it will be quite a heroic achievement. We need plan A, and a plan B.”
More study sites are about to open in other countries, and between May and July another handful of different vaccines is set to begin first-in-human testing.
There’s no shortage of volunteers.
“This allows me to play a small role in fighting this thing. I can be a guinea pig,” said Anthony Campisi, 33, of Philadelphia, who received his first test dose of Inovio Pharmaceutical’s DNA-based vaccine at the University of Pennsylvania last month.
The initial vaccine candidates work in a variety of ways. That’s important because if one type fails, maybe another won’t. Different types of vaccines work better in some virus families than others. But for coronaviruses, there’s no blueprint.
Back in 2003, when scientists attempted vaccines against SARS, a cousin of the new virus, animal studies hinted at safety problems. But then SARS disappeared and vaccine funding dried up. Vaccines against another COVID-19 cousin named MERS have only reached first-step safety testing.
“In 2020 hindsight, we should have worked harder on coronavirus vaccines back then. Now, we’re obligated to try a variety of strategies if we want fast results,” said Dr. Sten Vermund, dean of the Yale School of Public Health.
China’s Sinovac and SinoPharm are testing “inactivated” vaccines, made by growing the new coronavirus and killing it. The companies have revealed little information about how the shots differ. But the technology is tried-and-true – polio shots and some types of flu vaccine are inactivated virus – although its hard to scale up to rapidly produce millions of doses.
Most other vaccines in the pipeline aim to train the immune system to recognize a piece of the new coronavirus mostly, the spiky protein that studs its outer surface.
One way: Use a harmless virus to carry the spike protein into the body. It’s easier to produce but determining which virus is the best carrier is a key question.
China’s CanSino Biologics brewed its vaccine using a common cold-causing adenovirus, engineered so it won’t spread in the body. And in case people’s immune systems fight off the cold virus before the vaccine can do its job, Pollard’s Oxford team, instead, chose an adenovirus that normally infects chimpanzees.
Another way: Inject a piece of the coronavirus genetic code that instructs the body itself to produce spike protein that in turn primes the immune system to attack. It’s a new and unproven technology but one that promises even faster production.
According to WHO, there are eight vaccines undergoing the human trail phase out of the total 102 candidates.
Following US President Donald Trump naming hydroxychloroquine as potential “game-changer” in the battle against COVID-19 pandemic, a number of other treatments are also being explored including the scientists testing to treat the infection using experimental anti-Ebola drug remdesivir and blood plasma treatments.
However, Nabarro has warned that the scientists might never be able to find a vaccine for coronavirus since this has happened before in the case of HIV.
“It’s absolutely essential that all societies everywhere get themselves into a position where they are able to defend against the coronavirus as a constant threat, and to be able to go about social life and economic activity with the virus in our midst,” he told CNN.
What if coronavirus never gets a vaccine
In 1984, US Secretary of Health and Human Services Margaret Heckler had predicted that a preventative vaccine for HIV would be ready for testing in two years. However, nearly four decades and 32 million deaths later, the world is still waiting for an HIV vaccine.
Even as coronavirus is not considered to be as extreme as HIV, that enters the body and gets itself attached to a person’s DNA so as to mutate in a single contact, the influenza-treating medications could only offer a trial and error method rather than a cure.
If plan A of developing a vaccine, which according to Trump should be ready by the end of 2020, fails, what is plan B?
The use of anti-HIV drugs such as Lopinavir-Ritonavir have been recommended to treat the COVID-19 infection in patients aged above 60 years, considering its function of preventing the virus from mutating and multiplying.
While anti-HIV drug combinations fail to act as cure, the patients can live a normal life with HIV or AIDS by taking these drugs and so could the coronavirus-infected patients.
Paul Offit, a pediatrician and infectious disease specialist who co-invented the rotavirus vaccine said, “In HIV, we’ve been able to make that a chronic disease with antivirals. We’ve done what we’ve always hoped to do with cancer. It’s not the death sentence it was in the 1980s.”
On the contrary, Keith Neal, Emeritus Professor in the Epidemiology of Infectious Diseases at the University of Nottingham, told CNN that the drugs chosen till now for clinical trials are the best and could help.
Vaccines made by NIH and Moderna, Inovio Pharmaceuticals, and that Pfizer-BioNtech collaboration use genetic code approaches.
Other methods too are in line: Vaccine made of spike protein nanoparticles, and even a nasal spray alternative to shots.
Most vaccine studies done, so far, track safety and find whether volunteers’ blood shows any immune reactions. Some have jumped to larger numbers quickly, but there’s still concern about being able to provide real-world protection.
(With inputs from agencies)