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.
About 100 research groups are pursuing vaccines
with nearly a dozen in early stages of human trials or poised to start. It’s a
crowded field, but researchers say that 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 U.S. government’s top
expert, put it: “You need more shots on goal for a chance at getting a safe and
effective vaccine.”
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 U.S. and Europe to look for hints that
different vaccine candidates really protect.
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 to
overcome both obstacles in an attempt to compress the years it usually takes to
develop a vaccine. Asked if a vaccine by January was possible, Dr. Deborah
Birx, the White House coronavirus task force coordinator, told Fox News Sunday
“on paper, it’s possible. It’s whether we can execute,” she said.
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 how you count, there are between
eight and 11 vaccine candidates in early stages of testing in China, the U.S.,
Britain and Germany — a collaboration between Pfizer Inc. and BioNTech last
week began a study in Germany that’s simultaneously testing four somewhat
different shots. More study sites are about to open in still 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,” said Anthony Campisi, 33, of Philadelphia, who received
his first test dose of Inovio Pharmaceuticals’ DNA-based vaccine at the
University of Pennsylvania last month. “I can be a guinea pig.”
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 20/20 hindsight, we should have worked
harder on coronavirus vaccines back then,” said Dr. Sten Vermund, dean of the
Yale School of Public Health. Now, “we’re obligated to try a variety of
strategies if we want fast results.”
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 it’s 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. Vaccines made by NIH and Moderna,
Inovio Pharmaceuticals, and that Pfizer-BioNtech collaboration use genetic code
approaches.
Still more methods are next in line: Vaccine
made of spike protein nanoparticles, and even a nasal spray alternative to
shots.
Most vaccine studies so far are tracking safety
and whether volunteers’ blood shows any immune reactions. Some have jumped to
larger numbers quickly, but there’s still concern about being able to prove
real-world protection.
If study participants are holed up at home or
live in areas where the virus has quit spreading rapidly, then too few may get
sick for scientists to tell if the vaccine or social distancing was what
protected them. The Oxford study, for example, will track about 1,000 people,
half given the real vaccine. But the team plans a later-stage study with
another 5,000 volunteers for a final answer and knows it might have to move to
other countries.
“When you’re chasing a pandemic, the place that
looks like the right one to go to today will be the wrong place two weeks from
now. And that makes it really difficult,” Pollard said.
In the U.S., some lawmakers have urged a
different and controversial experiment: Recruit young, healthy volunteers who
agree to be deliberately infected with the new coronavirus to prove if a
vaccine protects them. But some healthy adults do die from COVID-19 — and until
doctors better understand why, that so-called “challenge study” makes for a
risky proposition with serious ethical questions, Yale’s Vermund noted.
The World Health Organization last week called
for countries to offer to be test sites for an international project that will
speed the timeline by admitting on a rolling basis promising vaccine candidates
for further study in locations where COVID-19 remains widespread at the time.
In the U.S., the Trump administration is
planning its own project dubbed Operation Warp Speed that will overlap studies
of “different candidates that are made differently and act differently,” Birx
said.
If early evidence was strong enough and the
virus is still widespread, the Food and Drug Administration might even consider
emergency use of a vaccine before final test results were in, Dr. Peter Marks,
who directs the FDA office that oversees vaccines, recently told reporters.
Whenever the first useful vaccine is
identified, there won’t be enough for everyone. So a growing number of vaccine
makers say they’re already starting to brew tons of doses — wasting millions of
dollars if they bet on the wrong candidate but shaving a few months off mass
vaccinations if their choice pans out.
“We need to start building new manufacturing
sites now,” said Wellcome Trust vaccine chief Charlie Weller. “And we need to
accept that some of these sites will be created for vaccines that will ultimately
fail.”
It’s not just a gamble for shareholders. The
U.S. government already has deals with Moderna and Johnson & Johnson that
together total nearly $1 billion and include scaling up production.
“The critical thing at the beginning is just to
make as much stuff as we can,” said Dr. Richard Hatchett, CEO of the Coalition
for Epidemic Preparedness Innovations, which is funding several COVID-19
vaccine attempts around the world.
Even if one works, expect rationing early on as
policymakers determine who most needs the first doses — possibly health workers
or the elderly — until there’s enough for the world, rich and poor countries
alike.
“I am concerned about what I call vaccine
nationalism. That’s the tension between obligations elected leaders will feel
to protect the lives of their citizens” versus the imperative for equitable
global sharing, Hatchett said.
And with billions who’ll need a dose or maybe
several, just one winner in this race won’t cut it.
“It’s not likely that one manufacturer or one
candidate vaccine is going to be able to deal with the global need and supply
that need,” Pollard said. - AP
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