- [Daniela] In response to the coronavirus crisis,
researchers are working at a breakneck pace
to develop solutions that will allow economies
to reopen safely and permanently.
- Without an effective vaccine,
we won't be able to get this pandemic under control
and stop the devastation that it's currently causing
all around the globe.
- Vaccines can take an average
of 10 years to develop, according to a 2013 study,
but researchers and pharmaceutical companies
are hoping to bring their vaccine candidates
for the new coronavirus to market in 12 to 18 months.
Some are even talking about getting
Emergency Use Authorizations before the end of the year.
So what is making it possible
to expedite this process so dramatically?
There are several factors,
including prior knowledge of coronaviruses,
specifically SARS and MERS,
improvements in sequencing of viral genomes,
advancements in bioengineering technologies,
unprecedented government support and funding,
plus a shortened testing timeline.
Traditionally, after scientists develop a vaccine candidate,
they run it through a series of tests.
This starts in cells, and then transitions to animals,
usually beginning with mice
and eventually progressing to monkeys.
Testing only advances from one phase to the next
if it's proven to be safe and effective.
- At that stage, you would then likely perform
what we call a challenge study,
so that would be vaccinating an animal
then intentionally giving them the virus
and seeing the impact of your vaccine on that disease model
where, of course, you would hope to protect it.
- Then they'd use that data to get approval from regulators
like the FDA to begin human testing.
There are three stages of human trials,
each one testing more people than the last.
Approval is required for each stage.
Instead of this relay approach
where researchers wrap up each set of experiments
before embarking on the next round,
developers are now doing many tests in parallel.
- So we're not skipping steps, but we're doing things
at the same time, which of course costs a lot more
and is a lot more work than doing it one after the other,
and that's the key difference.
- The novel coronavirus was discovered and sequenced
less than six months ago.
Several candidates are already in phase one of human trials,
including those made by Inovio and Pfizer,
even as companies await results from animal studies.
Moderna recently started phase two.
Others are gearing up for phase two
before phase one wraps up.
- Our phase one trial will run for a year,
but we're not going to wait for that full year period
to have elapsed before we hopefully move on
to the next stage of efficacy testing.
- Because of the worry of COVID-19 being so devastating,
we are expediting those processes,
and this oughta concern, because we don't really know
all that much about immunity to this virus,
that we may be going too quickly,
but so that's the balance here.
- [Daniela] Vaccines work on a simple premise.
They trick the body into thinking a virus has infiltrated it
so the immune system kicks into action
and starts producing antibodies and other defenses
against parts of the virus.
In this case, scientists think their target
is the spike protein, which the coronavirus uses
to get into cells.
- It's been shown from SARS and MERS
that the spike protein is the major protein
on the outside of the virus of these coronaviruses
to which erase neutralizing antibodies,
and neutralizing antibodies is what you need
to fight the infection.
- So what would really end the pandemic
is when there's enough immunity in the population,
and either than immunity
comes from everybody getting infected
or it comes from a vaccine,
and it's a much gentler path for everybody to get a vaccine
than for everybody to get infected.
- [Daniela] This concept is known as herd immunity.
Dozens of companies and labs are trying various technologies
to develop vaccines that would get us there quickly.
Scientists say it's the largest,
most collaborative vaccine development effort
they've seen in their lifetimes.
They're testing four main strategies,
weakened viruses, proteins,
viral vectors, and genetic code vaccines.
Weakened or inactivated virus vaccines
are the most common.
That's your annual flu shot.
We have the most experience with these,
but they can also be costly
and time-consuming to mass-produce,
so in this case, they haven't been the preferred approach.
Protein-based vaccines
carry key parts of the virus into the body.
For coronavirus, that's the spike protein.
Sanofi and GlaxoSmithKline
are among dozens of developers taking this approach.
For viral vector vaccines,
scientists use an inactivated virus and stuff it
with the genetic code for the spike protein,
which our cells then use to turn out viral proteins.
The immune system then recognizes those as foreign.
Johnson & Johnson is developing this type of vaccine
for the coronavirus.
- [Gert] We use adenovirus vector,
and this adenovirus is a common cold virus
which normally doesn't cause any major disease,
just a common cold.
In the adenovirus, it becomes replication incompetent.
- [Daniela] In the fourth and final category
are genetic code vaccines.
These contain the instructions for the spike protein.
COVID vaccines being developed by Inovio,
Pfizer, and Moderna fall into this category.
These types of vaccines have never been approved
for humans before,
but they're generating a lot of excitement.
- The reason we're seeing them out in front is the speed.
- The speed in the manufacturing and the development?
- Yeah, really, both.
Proteins are more diverse.
They have all kinds of different shapes
and characteristics and so you have to play with a lot more
to actually get a protein-based vaccine made.
- [Daniela] Pfizer is running multiple candidates
through phase one trials in the U.S. and Germany
to cut down on development time.
- And even before we know whether the vaccine works or not,
we're starting to ramp up manufacturing capacity
so that we're ready to make it right away.
The key things you have to establish to develop a vaccine
are that it is safe, that it's effective,
and that every time you make it, it comes out the same,
so those key steps don't change whether you're going fast
or you're going slow.
- Changes in manufacturing can introduce unforeseen issues
that could make a vaccine dangerous.
That's what happened with the since-discontinued
polio vaccine decades ago.
Safety is a major concern,
because vaccines are given to healthy people,
so scientists have to ensure they don't affect things
like liver or heart function among other factors.
There are other issues as well.
Even if companies are able to come up with a vaccine
in less than two years, the vaccine research community
is concerned with how they'd be able
to produce and distribute it to everybody on the planet.
- So we are aiming to produce one billion dose
by the end of 2021, and some other companies
are committing to the same kind of scale,
either hundreds of millions or billions,
but still, it will not be enough for everyone.
- What is a big unknown is what the durability
of that protection is.
Is it going to be a year, two years,
or even maybe, unfortunately, six months or less,
because if it is measured in several months
instead of years, which is entirely conceivable
that that would be the case,
then we have a secondary problem.
How often do you need to boost somebody
to keep that level of immunity up?
- [Daniela] The final and perhaps most important hurdle
for coronavirus vaccine development will be human behavior.
- Are people gonna be accepting of this vaccine?
That's been such a huge problem in this country.
You know, if you have 50% of people
saying I'm not gonna take it under any condition,
then, of course, you've lost the whole battle.