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 As some companies close in on unveiling their initial findings -
with Canadian and European regulators already reviewing early data
on some vaccines - the following is what we know about the race to
deliver vaccines to help end the coronavirus pandemic that has
claimed over a million lives:
Who is furthest along?
U.S. drugmaker Pfizer Inc <PFE.N> with German partner BioNTech SE
<22UAy.F>, U.S. biotech Moderna Inc <MRNA.O> and Britain-based
AstraZeneca Plc <AZN.L> in conjunction with University of Oxford
researchers could provide early analyses of data from their various
large trials over the next two months. Johnson & Johnson <JNJ.N> is
not far behind.
What happens in these trials?
The companies are testing their vaccines against a placebo -
typically saline solution - in healthy volunteers to see if the rate
of COVID-19 infection among those who got the vaccine is
significantly lower than in those who received the dummy shot.
Neither trial participants nor researchers know who has received the
vaccine or placebo until the data is ready for review, or unblinded.
The studies rely on subjects becoming naturally infected with
COVID-19, so how long it takes to generate results largely depends
on how pervasive the virus is where the trials are being conducted.
In areas with large outbreaks and community spread, infections will
pile up faster.
How will we know if the vaccine works?
The United States, the European Union, the United Kingdom and the
World Health Organization have all set similar minimum standards for
effectiveness. Vaccines must demonstrate at least 50% efficacy -
meaning at least twice as many infections among volunteers who got a
placebo than in the vaccine group. Independent panels oversee the
trials to monitor for safety and effectiveness since the data is
hidden from companies and researchers. These data safety monitoring
boards take a peek at the interim results at pre-determined
milestones, such as after a certain number of people have become
infected. It the vaccine is looking significantly better than the
placebo, the companies can apply for emergency use, and the study
may be halted or continue to its intended conclusion. A trial also
can be halted if the panel determines the vaccine to be unsafe.
Will regulators ensure a vaccine is safe before making it available
to the public?
The U.S. Food and Drug Administration has said it will not approve a
vaccine unless it is both effective and safe. On Tuesday, it added
more stringent safety guidelines for U.S. vaccines. The FDA wants
developers to follow trial subjects for at least two months after
they receive their final vaccine dose to check for any side effects
that may crop up. The agency will consider an emergency use
authorization (EUA) once that data is collected from at least half
of the trial's participants. The UK Medicines and Healthcare
products Regulatory Agency will review the vaccines for the U.K. and
the European Medicines Agency will review vaccines for European
Union use.
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When will regulators decide?
Regulators will review the vaccines after the companies have enough data to
submit applications seeking an EUA or formal approval. Pfizer/BioNtech will
likely know how well its vaccine works as soon as this month, while Moderna’s
first look at data is more likely to come next month. AstraZeneca could provide
a look at late-stage data in the next two months. Regulators for Europe and
Canada are considering data on a rolling basis, as it becomes available. The
U.K. and the U.S. both expect speedy reviews of initial data for possible
emergency use before more traditional lengthy reviews for formal commercial
approvals.
Could these be the first approved coronavirus vaccines?
Yes, although China and Russia are on a similar timeline. China launched an
emergency use program in July aimed at essential workers and others at high risk
of infection that has vaccinated hundreds of thousands of people. At least four
vaccines are far along including from China National Biotec Group (CNBG),
CanSino Biologics and Sinovac. Sinovac and CNBG have said to expect early trial
data as soon as November. Russia’s Gamaleya Institute has begun a 40,000-person
late-stage trial and is expected to have early data at the end of October or
early November. Russia has also given the vaccine to at least hundreds of
“high-risk” members of the general population.
Is U.S. authorization up to President Trump?
The FDA must make sure that the benefits of a vaccine outweigh the risks before
authorization since they are intended to be given to hundreds of millions of
healthy people. However, the U.S. Department of Health and Human Services (HHS)
has the authority to override the FDA's recommendation. U.S. President Donald
Trump has complained about the new safety guidelines that would likely delay any
vaccine availability until after the Nov. 3 presidential election. The Trump
administration can hire and fire HHS officials, opening the possibility of
political pressure to approve a vaccine.
(Reporting by Carl O'Donnell in New York; Additional reporting by Julie
Steenhuysen in Chicago, Michael Erman in New York, Ludwig Burger in Frankfurt,
Alistair Smout in London and Polina Ivanovo in Moscow; Editing by Caroline Humer
and Bill Berkrot)
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