00:00:00,080 --> 00:00:04,720
I read that if just a single
parasite makes it to the liver,
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it can cause an infection. Is that true?
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00:00:06,640 --> 00:00:10,240
Yeah, that's right. And I think that's
the really tough challenge with Malaria.
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The reality of this problem is the
hardness of it is set by nature,
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00:00:14,880 --> 00:00:17,440
and nature is a vicious test setter.
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00:00:17,440 --> 00:00:21,840
Adrian asked if I wanted to stay on, this
was the PhD project that he pitched to me.
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00:00:21,840 --> 00:00:27,200
I thought it sounded quite interesting to make
a new vaccine. There was a lot of iteration.
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00:00:27,200 --> 00:00:31,040
The first time I saw the particles under
electron microscope that was really exciting.
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Would you participate in the challenge trial?
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I would love to, but I really
hate needles. I have to lie down.
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Otherwise I might faint. It's kind
of ironic for a vaccine developer.
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00:00:41,520 --> 00:00:44,880
There are people like Katharine
Collins who invent entirely new
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vaccines that are now gonna be used
by millions of children. You may know
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one of these people. You may become
one of these people in the future.
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00:00:58,320 --> 00:01:02,800
Malaria kills around 600,000 people a
year. Most of them are young children
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in Sub-Saharan Africa. It's caused by
a parasite, not a bacterium or virus,
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and it's spread by a mosquito. Until recently,
the only control measures were insecticides and a
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handful of anti-malarial drugs. But in the last
few years, we finally got effective vaccines.
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Two malaria vaccines have now received WHO
recommendations and are being rolled out
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across Africa. And for the first time ever,
a human-infecting parasite has a vaccine.
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Getting here took longer than it
should have. The first malaria
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vaccine was developed and tested in the nineties,
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but it's spent 23 years in clinical trials and
pilot tests before it was licensed and rolled out.
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So in this episode, we're going to cover
the science of why malaria is so hard to
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vaccinate against, how the vaccines
actually work, why it took so long,
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what we can do to speed up the rollout
now, and what even better vaccines
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are being tested now for fewer doses
and longer durability in the future.
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Today's episode is special because
we're joined by Katharine Collins,
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who co-invented the second malaria vaccine during
her PhD, and she can tell us what it was actually
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like from the inside. Welcome to Hard Drugs,
hosted by me, Saloni Dattani, and Jacob Trefethen.
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Okay, so we have some news
today, right? Because Jacob,
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you have started a new job. Could you
tell us about what you're doing now?
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I'm gainfully employed. I'm working at a new
foundation making grants to science still,
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00:02:34,480 --> 00:02:42,000
but from a different vantage point. It's the
OpenAI Foundation and we have been getting
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started in science, so it's kind of exciting,
a little bit different than my previous job
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which was at Coefficient Giving. And the
previous job was quite fun. But you'll have
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to ask around what my reputation was there, for
example, Katharine, what was I like back then?
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Jacob, you were the best manager I've ever had.
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00:03:03,600 --> 00:03:15,440
No no, we can't include that! No, no.
Expulsion! No, my biggest difficulty
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of changing jobs is that I don't get to
work with some of the wonderful people
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00:03:18,880 --> 00:03:27,520
I worked back at Coefficient Giving with, like
Chris Somerville, Ray Kennedy, Heather Youngs,
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00:03:27,520 --> 00:03:33,760
Rafael Dib, Douglas Chukwu. Oh gosh. So
many people, Aisling Leow. And guess who?
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00:03:33,760 --> 00:03:40,640
Katharine Collins. Now the good news is
that Katharine at least is here today.
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So Katharine is joining us from
Coefficient Giving as well, and is a
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very special guest on today's episode because
she co-invented the second malaria vaccine.
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00:03:56,800 --> 00:04:03,280
Now we are lucky at Hard Drugs to have listeners
around the world, and that means I'm going to
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start here with some insight into the British
psyche. For those listening from other places,
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we have a guest on today who is an inventor and
she's also British. That means that she's very
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reticent to take credit for things, even things
she invented, so it took a lot of cajoling to get
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her onto this episode, though we knew if we could
pull it off that our listeners would love it.
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So I am very grateful for the willingness of our
guests to be cajoled, but I should say upfront,
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as part of our ability to pull it off,
that there are many other people involved
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in the story of malaria vaccines and of R21 in
particular, who we won't get to have on today,
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who took forward the vaccine into clinical
trials, who did all the work to make sure
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it could get approved and used by kids
around the world. So that's my proviso,
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that's the trade we had to make with our world
famous inventor. With that in mind, enjoy.
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So I have a question for both of you,
which is, do you have a favorite parasite?
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What I didn't realize until recently
was that fungi and plants can also
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be parasites. And so a parasite
could be a single celled organism.
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It could be an animal like a mosquito,
vampire bats, hookworms. Or it could
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be fungi like the ringworm fungi. Or it could
even be a plant, like mistletoe is a parasite.
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What?!
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Yeah, mistletoe is a parasite.
It attaches to other trees and
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extracts water and nutrients from them.
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Gosh. And here I was. Okay. I think I have two
answers. You brought up hookworm. Hookworm's
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one of my answers, tape worm's another one of
my answers. I mean, tape tapeworms disgusting,
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obviously, but you just have to
be impressed. They get so large.
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How large do they get?
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Like, I don't know, probably miles long. Joking.
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Wow.
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They get feet long for sure. And maybe meters. I
mean, I just think that's crazy. It's obviously
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gross, but luckily hookworms aren't gross
at all. All they do is hook onto the side
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of your gut and suck your blood. They come
up, they sort of get up through your foot,
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sneak - their whole life cycle's insane
- they eventually get down into your gut
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and hook onto it and start sucking your
blood. I mean, that's pretty impressive.
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Is that why they're called hookworms?
Because they hook onto your gut?
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You know, I've never thought of that. And
the answer is probably yes, but I don't know.
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And then are tape worms called
that because they look like tape?
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No, it's actually 'cause on
the underside, they are sticky.
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Oh, wow.
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That's a joke. Sorry. That's
a joke. That's a joke.
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Oh, you tricked me!
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First trick of the episode!
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Okay. My favorite parasite also, well, I'm
not impressed by this, I'm just so horrified
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by it that I have decided it's also my favorite.
And it's Guinea worm, which is so horrible. And
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people ingest the worm larvae when they drink
contaminated water. And the larvae get into
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your stomach, they get through your gut, and
then they grow into worms that can reach up to
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a meter long. And they kind of crawl through your
connective tissue and your joints, and then slowly
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erupt out of your legs - usually out of the skin,
near your legs. And the emergence is also very
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slow. And the way that you remove the worm is
by slowly winding the worm around a small stick,
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and if you go too fast, the worm snaps and dies,
and that causes severe inflammation in your body.
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That sounds like it was invented
by Jigsaw from the series Saw as
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a patient to someone who was impatient or
something. Okay, well thank you for that.
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Wait, wait, wait. The good news is
though, we've almost eradicated it.
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Isn't that great? So it used to cause like a
million or more cases per year in the 1980s,
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and it turns out just cleaning up
the water, filtering drinking water,
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or telling people not to drink from
stagnant water can help prevent infections.
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Do you know how near eradication we are?
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I think there were 10 cases
reported in total last year.
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Wow!
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Wow. That's incredible.
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Yeah, so from millions per year
to 10. What about you Katharine?
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Yeah, mine's really boring. Mine's the malaria
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parasite. I can't say anything else
after studying it for two decades.
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Yeah, it would be really surprising
if you said something else.
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Yeah, it would kind of be
like adultery or something.
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In this episode we're going to talk a lot about
the two malaria vaccines that have been rolled
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out. The first one is called RTS,S and it was
developed in the 1990s. The second was R21,
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it was invented by Katharine Collins, who's
here with us today, and it was based on the
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first one. So those are two names that we're
gonna refer to throughout the episode. RTS,S,
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the first malaria vaccine and
R21, the second malaria vaccine.
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I guess it's easy to remember because
the second one has two in it, R21,
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but just in case that is confusing; those are
the two names that you've gotta remember. RTS,S,
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the first malaria vaccine and R21, the second.
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Maybe let's start with how you got into
malaria research in the first place.
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What drew you into the field? Or how
did you get into vaccine research?
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I had done my undergraduate and my master's
degree in basic research and not in global
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health. I did various projects in different
disease areas, but it was really about trying
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to understand the fundamentals and different
signaling pathways and things like that. So I
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think one of my projects identified a protein
interacted with another protein in a pathway.
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And while that was cool, and I loved science
and it's definitely where I'm supposed to be,
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but it I didn't see how that was gonna have
any direct impact on health in the near term.
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I actually started looking for jobs, or how
I could have an impact in global health,
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or how I could transition from science into global
health work, and it wasn't really clear. And then
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this job was advertised at Oxford University to
work on malaria vaccine trials. And I thought,
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wow, that's global health. I should just take
that job, and or apply for that job, and that
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may open doors. And so I did. And I really loved
working on malaria. It was instantly something I
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was really passionate about, really motivated
to work on. It's just a fascinating parasite.
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So the job was a research assistant
on malaria vaccine trials. So the
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Jenner institute at Oxford, where
Adrian Hill's group that I joined,
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they were testing a number of different
candidates in malaria trials. And my job
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was to help coordinate those trials and to
do all the immunology in the background.
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And then how did that turn
into inventing a new vaccine?
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Yes. Well, after being there for about a
year, Adrian asked if I wanted to stay on,
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and do a PhD. The project idea was that
Adrian had developed a vaccine that targeted
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the malaria parasites, whilst they were in
the liver. It'd been shown to protect some
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people against infection, but it was quite
a low level, I think it was 20% efficacy. So
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the idea was to combine this liver stage
vaccine for the vaccine that could also
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prevent the malaria parasites before they get
to the liver. So stop them invading the liver.
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And the leading vaccine at that time targeted
the parasites before they invaded the liver,
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and this was a circumsporozoite based vaccine
called RTS,S, and it was developed by GSK.
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So he wanted me to work on making a newer
version, an updated version of that vaccine.
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That's so cool. I feel like compared to - so
my PhD was very boring in comparison to this,
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and it makes me think that there's actually -
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Wait, Saloni, did you not
invent a vaccine in your PhD?
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I know, I feel like people should know upfront
that some PhDs are better than others. You know,
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some fields are better than others. So
who else was involved in this? Did you
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have mentors, collaborators, rivals, or enemies?
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I worked fairly alone in the lab. I did have
a few people that were supporting the work as
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well. So my PhD supervisors were Adrian Hill
and Sarah Gilbert. There were also a couple
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of postdocs and technicians and PhD students that
helped me with various parts of the project over
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the years. For example, someone actually
helped me vaccinate all the mice that we
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used for the preclinical experiments.
And then I did the immunology myself.
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And Sarah Gilbert is the inventor of
the AstraZeneca vaccine, is that right?
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That's right. Yeah.
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For COVID. Got it.
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Yeah.
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And rivals?
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Rivals, well, oh, you're asking the good
questions. I guess in the field at the time,
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there were lots of people trying to
develop a malaria vaccine. I guess
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there was competition between the different
groups to see who would get there first.
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And whilst I was working on it,
RTS,S hadn't crossed the finish line,
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but it was obviously way, way, way further
ahead in development. So the expectation
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was that that vaccine would move forward and
get approved first, and then R21 may follow.
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Right. And by that point, had
the RTS,S patent already expired?
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Yes, actually that's right.
So if I remember correctly,
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it was due to come off patent. And
interestingly, that was essentially
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the starting place for learning how to
make R21. So I reviewed that patent,
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I looked at how they've made RTS,S, and then
I made a plan for how to go about making R21.
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Did that have enough information
for like? What was that like?
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So RTS,S is actually made with a lot of a
protein on the surface of the Hep B virus.
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This is the Hep B surface antigen and that was
needed to make it form the virus like particle,
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but it had quite an excess of Hep B
surface antigen. So it's actually a
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really good Hep B vaccine, and not a terribly
good malaria vaccine. So my project was to see
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if we could remove some of that Hep B and
actually make it a better malaria vaccine.
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And we had established a plan for how we're
going to get there. So initially we wanted
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to just replicate the RTS,S process in the lab and
then try a few different things to see if we could
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get the particle to form without this excess Hep
B surface antigen. One approach was actually to
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just try and chop out some of the malaria protein
out of the vaccine and remove some of the T-cell
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epitopes, which were in there, and a few other
bits as well, and see if the smaller protein would
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be more able to form particles on its own. The
other way was just to try and reduce the amount
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of extra Hep B that we were adding and see if it
could form particles on its own that way, by using
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some of these newer yeast expression technologies
to grow the protein and new methods to purify.
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I think RTS,S had something like a 12 step
purification process at least in the patent, and
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that might not be what they used anymore. But I
wasn't really interested in trying to set up this
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12 step new process in an academic lab. You know,
I'm not a biochemist. So I essentially looked at
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their process to understand what they had done
and why, and then developed a purification
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process using a combination of some of those
old methods and some of the newer technologies.
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I feel like my immediate question is why
didn't the developers of the RTS,S vaccine
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do that? Like if there were various
steps that didn't need to be included.
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Yeah, I mean, they probably did. I mean, when
they first patented what they were doing,
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it probably had this multi-step process.
Maybe they had different process they were
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using lots of different methods, so
they patented the whole process and
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I'm sure they probably optimized that as they
scaled up and improved their manufacturing.
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I wanna just get a more of a sense of what it
feels like to be in the lab alone, toying with
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different steps of purification, and how long were
you - did you feel sort of lost versus actually,
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it worked pretty quickly and you got, once you
saw in the electron microscope, you're like,
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oh God, it's actually gonna work. Was that
pretty quick or you were there for months,
199
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years? You're tinkering. What did
the invention process feel like?
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Actually, I think I was interviewed
by someone a while ago and I,
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my recollection is that it was very quick
that I kind of give it a go and it worked.
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Wow.
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And then I thought, now I thought, is this true?
And I went back to my lab notebooks and I had a
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look through like the electronic notebooks and I
had a look through and it wasn't that quick. There
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was a lot of iteration, a lot of optimization
that happened with every single stage.
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So we were using yeast to express
the protein and grow the protein,
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and there were four different strains we were
testing, and then for each different strain, we
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picked multiple different colonies, and I screened
all of these different colonies first to find the
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best expressing colonies, and then I started to
try and purify it, to purify them. And I probably
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used multiple different techniques until I got
something that looked substantial. So it wasn't
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that quick. So I think it was a long time ago
now, so my memory's a bit optimistic maybe?
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So am I imagining right that it's like, you
have the instructions-ish from the patent
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and then you're trying out different options,
like different versions of the yeast, different
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versions of the purification process, and at
each step trying to optimize which is the best
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one to go forward with or something like that?
Or is that not the right way to think about it?
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Yeah, that's just about right. There are a lot
of newer technologies available for purifying
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proteins and particles, so it's kind of a
process of looking at which steps could be
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replaced by newer technologies and going for
something that was more modern and simpler,
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where that was possible, and where
there wasn't a newer technology,
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we were sticking with that whole process as well.
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So you were at the Jenner
Institute, is that right?
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That's right.
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Do they have just people working on
many different diseases and like trying
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to develop vaccines against all of them, or
are there some areas that they focus on? Or,
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are lots of people doing this during their PhD?
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I think developing a vaccine was rare, fairly
novel at the time, or quite rare. So not a huge
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number of people were doing it. There were
three PhDs I can remember that developed
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a vaccine during their PhD and I was one of
them, but there may have been others as well.
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But in terms of the structure at the Jenner
Institute, there were different group leaders,
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or PIs, that have their focus area, and
the Jenner Institute was generally open
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to having new people join the institute. And
if there was space, they did actually join
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the physical lab space as well. So we had work
going on on multiple diseases at the same time.
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Okay. So you're, you're tinkering,
you're tinkering, you're tinkering,
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you look under the electron microscope
and then you test something in mice and it
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protects them from malaria. Did it feel like
a eureka moment at any points of that step,
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or was it just iteration? Iteration, feels
good, feels a bit better, feels a bit better?
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No, definitely a few eureka moments. I mean,
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the first time I saw the particles under the
electron microscope, that was really exciting,
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especially when I had used the process that we
didn't think that was possible. So by removing
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all the excess Hep B, that was really cool when
we could see those, and they looked very similar
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to the Hep B particles. So it was it was really
reassuring that we were doing something right.
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Then the next push was to move
that into a preclinical study,
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to inject mice and see if we get an immune
response, and then if we can protect the
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mice as well. And whilst I was optimizing the
process, the yield was really, really low of
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the particles. And I tried to concentrate it
and it wasn't easy to concentrate. So we ended
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up injecting an incredibly low dose into the
mice and it was like, well, we might as well,
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we have the product, let's just see what it
does. And then it protected all the mice.
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And so that was really exciting. We had
gone for this dose that was dramatically
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lower than any other dose we normally test
in the lab. And the vaccine I think 10 times
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lower than any other dose that had showed
for RTS,S being tested in mice and that it
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worked. So that was really exciting. That was
the one of the really exciting moments. Yeah.
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That's super cool because
if you have a lower dose,
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you can vaccinate more people
with the same amount, right?
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Yeah, exactly. And a tenfold lower dose, that's
huge. That's not half the doubling the number
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of people. That's a dramatic increase. But
actually at the time there wasn't a lot of
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information on how well dose in mice would
translate to humans and if it would actually
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result in a lower dose human vaccine. We did
later find out that it was easier to scale up.
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So, interesting how the practical constraints -
let's say it had been effective but you would've
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needed five times more product. Is it possible
you would've just dropped this lead and focused
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on something else 'cause you couldn't
make enough, or what would've happened?
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No, I was really early on in the purification
process, in optimizing that. So it was just that,
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it was just of luck. But we had
gone in with such a low dose to
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begin with. Maybe we would never have
got to the low dose, that lower dose,
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if we haven't had that constraint
on the concentration of the product.
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Okay. So all of this is happening in your
PhD, was that 2010 to 2014? Is that right?
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Yeah, well remembered!
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So we now know, with the benefit of
hindsight, that R21 works in kids,
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in humans, and it protects babies against
malaria. And that took time to prove out
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any clinical trials, and there was
- to give a spoiler to the audience,
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the R21 vaccine was actually approved
a couple years ago for wide use.
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Along that journey, you finished your
PhD and you started doing other malaria
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research elsewhere. Did you, when you finished
your PhD in 2014, did you have a feeling that,
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oh, I just invented a vaccine that's gonna
get used by millions of people? Or did it
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feel more like, okay, I've proven out that
this might work and I'm gonna pass it on,
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but it's, we'll see. Yeah. What did it feel like?
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I think most people in the field were quite
skeptical about R21 in the early days. They
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couldn't really see the point in making
a vaccine that was so similar to RTS,S.
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And the initial results, kind of backed
that up, that there was reasons for that
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skepticism. It didn't look very different in
the preclinical work, in the mice studies,
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there wasn't a really strong reason to
think that this was gonna save a lot
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of lives, when there was already
a vaccine that was very similar.
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But the dosing was very different, right?
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It was, and I think this is a lesson for
vaccine developers, right? At the time,
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everybody was quite negative about R21. But if you
think about things like being able to reduce dose,
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making it simpler and easier to manufacture,
even small increases in immunogenicity,
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if you add all of those benefits together,
you end up with a product that's easier to
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deploy, a lot cheaper, and maybe easier to
manufacture. So it can really have an impact,
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without just making a dramatically
better vaccine in terms of efficacy.
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It's sort of scary though, 'cause I think I, as
a outsider who has never developed a vaccine,
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if I had seen the results from preclinical
tests in animals and the results said, well,
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we can't distinguish that this is better from
RTS,S, I probably would've killed it. And yet
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now we know that it is much cheaper to produce
and it's more manufacturable and it's longer
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durability. I mean, so it's sort of terrifying.
What was in the system that allowed this one to
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actually go forward and now it's reaching people.
You know, is it as contingent as it sounds to me?
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Yeah. You know, I think this was - all the credit
goes to Adrian Hill for pushing it forward and
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really finding out what it could do in people,
right? I think so many people would've dropped
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the vaccine at this point. And another difference
that we haven't mentioned so far is that R21 also
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used a more scalable adjuvant, and I think that's
quite important for the supply argument as well.
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An adjuvant is another ingredient in the
vaccine that strengthens its immune response?
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Yeah. Yeah, absolutely.
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Alright, and so these were
different between the two vaccines,
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and the R21 adjuvant was cheaper
to produce and easier to scale up.
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Yes, absolutely. Yeah. The adjuvant used
with the, with RTS,S is a GSK adjuvant. It's
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also used in another product, and yeah, much more
difficult to scale, and much more limited supply.
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I remember reading that it comes
from - that adjuvant comes from the
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tree bark of a South American tree. Is that right?
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Yeah. And that comes from the bark of
a Chilean - I can never get the name,
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pronounce the name right, is a Quillaja
tree (Quillaja saponaria, soapbark).
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Does that mean that you have to get that tree to
get the adjuvant? Is that why it's difficult to
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scale up? And how come the second one is easier
to scale up if they're both from these trees?
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So the supply limitation is the availability
of the trees, the raw material, and also the
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purification process. So if you imagine you're
purifying all these products from the bark of
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the tree, or from the tree, and if you purify and
throw away a lot - a lot of it away, it's gonna
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be more expensive and harder to scale. They've
improved the ways they're producing the trees,
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so supply is increasing and it's gonna
be less of a limitation moving forward.
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And people are also working on
synthetic versions and special,
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not sure the right word, aquaculture style
(hydroponics) growing of these, of these trees
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and different methods of harvesting
from them to get the components.
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Is it like someone shaving parts of
a tree off and then doing some other,
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like, how does this all work?
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I've never seen anybody do it that, and that's
kind of how I imagined it, taking the bark off.
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But other thing I should mention is you have
to like harvest most of the tree or you have
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to kill the tree and that was the problem, and
so I think they've changed the way that they
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actually harvest from the tree so they can
keep growing as well in some instances. So
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you don't just have to - it takes 25 years
to get the tree and then you cut it down.
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So you're looking at your lab notes, Katharine?
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Yeah, it's fascinating. I'm glad I kept
really good notes. It's really interesting.
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Are they dated?
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Yeah.
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What date are you looking at?
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Um, troubleshooting the purification
process, 23rd of the third, 2011.
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Whoa.
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Wow. What were we doing in 2011?
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Yeah, 23rd of the third.
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I was in school.
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I was inventing vaccines, actually, Saloni.
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You didn't tell me that.
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Yeah, I try to keep it private.
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So what happened on that day?
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I tested a few different methods and then
the result: aggregation seen in sample.
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Okay. Bad.
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Second purification attempt: reduce aggregation.
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I love it.
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Do you have any, um... random comments in there?
Do people put in computerized doodles? Emoticons?
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No. Definitely not, emojis
didn't exist then, Saloni!
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No, but emoticons did.
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LOL.
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XD
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Aggregated again, LOL. Wait,
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so how many experiments are you doing? Is
this like every day you have new entries?
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Yeah, yeah, yeah.
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Wow.
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No, every couple of days. So I guess
I'm gonna test this and then it
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takes a few days to test and then...
results: aggregation seen in sample.
355
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ROFL. Are there images of the RTS,S or R21 under
the microscope? Should we- we should include one.
356
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Well if you are up for it - us including
some screenshots might be kind of fun for
357
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viewers. Oh my gosh, no. Sorry. We have
thank goodness. We have to include this.
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Wow.
359
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This is so cool. Whoa. Okay, great.
360
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Wow. They're so cute.
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Okay, listeners, so we are looking at
two images here. On the left it looks
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like spots on someone's skin, maybe measles.
So talk us through the left here. Katharine,
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what are we looking at?
Those beautiful circles. Wow.
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So those, that's a transmission electron
micrograph of negatively stained R21 particles.
365
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Oh my gosh, that's so clear. They're
so clean. They're so circular.
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They're so blobby.
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I mean, just to restate some of, and
correct me if this is wrong, Katharine,
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but part of the reason why having these circles
that look like viruses is so useful is that
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our immune system is really good at attacking
circular viruses. So is that a fair statement?
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Uh, yeah. So they're easier to
recognize by the immune response,
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definitely. That's part of the
theory behind virus type particles.
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What reading this has just really made me realize
how much I was reinventing the wheel. Like if this
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was anybody else making it, or company making
it, you'd have had an expert in purification
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diving into this that would've been able
to, I had to do all the research myself.
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Oh my gosh. Wow.
376
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Yeah. And figuring it out.
377
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That's so cool!
378
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Yeah, that's even cooler.
379
00:31:32,080 --> 00:31:36,560
You know I did have support. There were other
people in the lab that I'd go to for advice,
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and I talked to Sarah and Adrian, but
I was often figuring it out by myself,
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or at least that's how I remember it.
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It's astonishing because I tend to, sometimes
I feel myself getting skeptical about patents
383
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in particular, where the trade that
society is making with inventors is
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that if you publish in public how you
did something, then we will give you
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00:32:02,880 --> 00:32:06,720
exclusivity for 20 years to do whatever
what you want. Sometimes I'm like, well,
386
00:32:06,720 --> 00:32:11,040
hold on. How much are you actually gonna be able
to learn from reading that? They're probably
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00:32:11,040 --> 00:32:15,680
gonna hide whatever they can and to get away
with it. And what, how can you learn something
388
00:32:15,680 --> 00:32:19,680
from reading? You need to see someone do it, but
you're telling me you literally read the patents
389
00:32:19,680 --> 00:32:24,960
and then you just kept plugging away until
you've simplified and fixed all of the stuff.
390
00:32:24,960 --> 00:32:28,400
I mean, that's awesome. That's
a one person show. And I'm like,
391
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wow. So knowledge in public
is a extremely big deal.
392
00:32:32,400 --> 00:32:37,040
Yeah. I think I managed to get it to the
point that we could make it ensure that
393
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it works. And then there was a huge amount of
work that happened by others to turn it into a
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00:32:42,240 --> 00:32:52,320
GMP grade process. And even then that was a
simplified or a shortcut version to get to a
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GMP product that was done by the clinical
biomanufacturing facility in Oxford. They
396
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did an enormous amount of work to produce the
first batch and then Serum got involved and
397
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they used all of their knowledge and knowhow
to probably dramatically change the process.
398
00:33:08,080 --> 00:33:14,160
So I wanna pause on that actually, 'cause it's my
day job is I'm a funder and then now your day job
399
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is, you're a funder, Katharine. And one thing
that comes out from this story that's really
400
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interesting is that a lot of universities where a
lot of knowledge is generated and science is done,
401
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do not have facilities to produce the vaccines
that you could take into humans safely,
402
00:33:35,440 --> 00:33:38,960
whereas Oxford does. Is that a fair
statement? And do you think that
403
00:33:38,960 --> 00:33:44,480
that allows for a knowledge generation
loop, which is unusually productive?
404
00:33:44,480 --> 00:33:48,640
Yeah, absolutely. I think that's definitely one
of the big advantages of being in the Jenner
405
00:33:48,640 --> 00:33:53,200
Institute. Adrian had set up this clinical
biomanufacturing facility and that meant
406
00:33:53,200 --> 00:33:58,240
he could really quickly iterate, he could design
something in the lab with a student designing it,
407
00:33:58,240 --> 00:34:03,200
and then transfer it to the manufacturing
facility and quickly produce a small batch.
408
00:34:03,760 --> 00:34:08,720
Does that mean we should have more
Jenner Institutes doing other - can
409
00:34:08,720 --> 00:34:12,880
you scale that to work on more diseases
or is it just really hard to do that?
410
00:34:12,880 --> 00:34:15,360
No, no, I think that's the way
- people should be learning from
411
00:34:15,360 --> 00:34:18,800
that model. I think it's not cheap
to maintain a facility like that.
412
00:34:18,800 --> 00:34:24,960
I have another question, which
is, why is it called R21?
413
00:34:24,960 --> 00:34:27,600
Uh...
414
00:34:27,600 --> 00:34:31,280
Is that a very complicated story?
415
00:34:33,040 --> 00:34:37,120
Um.. I can't remember.
416
00:34:37,120 --> 00:34:38,720
What?!
417
00:34:38,720 --> 00:34:40,160
Wow!
418
00:34:40,160 --> 00:34:45,920
Adrian came up with a name and I think
I remember asking him, and I think he
419
00:34:45,920 --> 00:34:56,240
said it was a 21st century version of a repeat
region vaccine. The repeat region is the part
420
00:34:56,240 --> 00:35:02,160
of the CSP protein that's included in RTS,S and
R21, and that's what the R stands for in RTS,S.
421
00:35:02,160 --> 00:35:05,120
Well, maybe you should ask him.
422
00:35:05,120 --> 00:35:08,640
Yes, right now.
423
00:35:08,640 --> 00:35:15,520
Alexander, why is it called penicillin? God,
I just can't remember. I can't remember.
424
00:35:15,520 --> 00:35:17,480
I've got an answer.
425
00:35:17,480 --> 00:35:20,320
Oh, we have an answer.
426
00:35:20,320 --> 00:35:27,040
So Adrian said it's the 21st century
presentation of the CSP repeat vaccine.
427
00:35:27,040 --> 00:35:29,840
So your earlier answer was basically correct.
428
00:35:29,840 --> 00:35:30,480
Yeah.
429
00:35:30,480 --> 00:35:36,480
That's great. It's so funny to me that
you thought that you had made it up,
430
00:35:36,480 --> 00:35:39,120
but you actually remembered it correctly.
431
00:35:39,120 --> 00:35:46,000
I have a similar but very different story
where I thought that my earliest memory ever
432
00:35:46,000 --> 00:35:53,040
was made up for a while and then I found
video evidence of it being true. So my,
433
00:35:53,040 --> 00:36:00,480
so my earliest ever memory is of us, my
family, going to the Grand Canyon and at
434
00:36:00,480 --> 00:36:06,400
the Grand Canyon I had a pink balloon and the
only thing I remember is that I had this pink
435
00:36:06,400 --> 00:36:13,040
balloon and I dropped it down the Grand Canyon.
And I remember mentioning this to a bunch of
436
00:36:13,040 --> 00:36:18,160
people afterwards and then eventually I was
like, did that actually even happen at all?
437
00:36:18,160 --> 00:36:23,120
Like that just sounds like such a crazy
story. Like why would I drop a balloon,
438
00:36:23,120 --> 00:36:29,440
that doesn't sound like me? Like I was two, but it
still doesn't sound like me. I wouldn't do that.
439
00:36:29,440 --> 00:36:36,400
And then last year I found a video that my
dad took of this whole trip that we took to
440
00:36:36,400 --> 00:36:43,200
the US when I was two. And in the video there's
a segment where I'm holding the balloon, the pink
441
00:36:43,200 --> 00:36:54,000
balloon. And in the background, you can hear my
dad telling me to drop it down the Grand Canyon.
442
00:36:54,000 --> 00:36:56,160
That is pretty much a clincher.
443
00:37:01,920 --> 00:37:07,920
I was like, wow. I finally feel so
validated. But also it wasn't me. I didn't,
444
00:37:08,560 --> 00:37:11,360
I wouldn't, I was just listening to my dad.
445
00:37:12,240 --> 00:37:13,440
There's a lot to unpack there.
446
00:37:13,440 --> 00:37:18,880
I was like, why would I litter?
447
00:37:18,880 --> 00:37:22,480
Oh... Right?
448
00:37:23,120 --> 00:37:27,600
That's not like me at all!
449
00:37:27,600 --> 00:37:29,600
It's all adding up now.
450
00:37:29,600 --> 00:37:32,080
Before we move on to the science of malaria,
451
00:37:32,080 --> 00:37:40,160
what happened after you invented the R21 vaccine
and what happened after you finished your PhD?
452
00:37:40,880 --> 00:37:50,000
Yeah, so after the vaccine was made, we then
first tested it in a mouse model of malaria,
453
00:37:50,000 --> 00:37:53,840
and we showed that we could
protect the mice against malaria,
454
00:37:53,840 --> 00:38:02,160
and this worked best when you used the right
adjuvant. And I did a large number of studies
455
00:38:02,160 --> 00:38:07,600
in mice to really look at the dose that was
needed, and that's really where my PhD ended.
456
00:38:07,600 --> 00:38:12,640
So once I developed the vaccine and we had shown
that it worked in mice, Adrian was moving this
457
00:38:12,640 --> 00:38:17,120
forward into clinical trials. So I had the
opportunity to stay at Oxford and continue
458
00:38:17,120 --> 00:38:22,160
working on the vaccine as it moved into the
human clinical trials. But I'd finished my PhD,
459
00:38:22,160 --> 00:38:27,200
so I decided I wanted to move on and broaden
my experience and learn some new skills.
460
00:38:27,200 --> 00:38:32,560
I moved to work with James McCarthy in Brisbane
and he had set up a model where you could infect
461
00:38:32,560 --> 00:38:39,200
people with malaria - this was a challenge trial
- and evaluate the efficacy of drugs. And so
462
00:38:39,200 --> 00:38:46,880
I was working there on those studies and also
developed a new challenge model as well. I then
463
00:38:46,880 --> 00:38:53,200
moved on to work in - on projects in the field,
understanding malaria transmission more fully,
464
00:38:53,200 --> 00:38:56,560
and looking at interventions to
interrupt malaria transmission.
465
00:38:56,560 --> 00:39:02,800
That work was mainly based in Burkina Faso and
it was based out of a lab in the Netherlands.
466
00:39:03,440 --> 00:39:06,960
Hmm. And then how did you get
from there to Coefficient?
467
00:39:06,960 --> 00:39:08,800
Jacob hired me.
468
00:39:08,800 --> 00:39:10,960
Oh, wow!
469
00:39:10,960 --> 00:39:13,760
No, I mean, it's an interesting story.
I wasn't particularly looking to leave
470
00:39:13,760 --> 00:39:18,640
academia. I was loving the work I was doing,
but obviously Coefficient Giving, or Open
471
00:39:18,640 --> 00:39:25,840
Philanthropy at the time, is a really exciting
funding organization that's quite innovative.
472
00:39:25,840 --> 00:39:28,480
And what happened to the vaccine after that?
473
00:39:28,480 --> 00:39:32,960
So Adrian then took the vaccine forward into
clinical trials and there were lots of other
474
00:39:32,960 --> 00:39:37,040
people involved in the development of the
vaccine. All the investigators in Africa,
475
00:39:37,040 --> 00:39:42,320
the clinical investigators in Oxford, and
also the Serum Institute who licensed the
476
00:39:42,320 --> 00:39:48,560
vaccine from Adrian and from Oxford,
and worked with the team there to carry
477
00:39:48,560 --> 00:39:53,680
out the phase three trials and then
obviously develop the final product.
478
00:39:53,680 --> 00:39:59,760
I think it's sort of underappreciated just
how many people work on these, like actually
479
00:39:59,760 --> 00:40:05,520
getting the testing and scaling up to people.
It takes so many people and it makes me think
480
00:40:05,520 --> 00:40:11,760
also that it's not just about funding, it's also
the number of people working on things like this.
481
00:40:11,760 --> 00:40:15,280
Yeah, I mean, absolutely. I think this large
number of people it takes is really important
482
00:40:15,280 --> 00:40:19,600
for me. I just played a very small role at
the beginning and there's such an enormous
483
00:40:19,600 --> 00:40:25,440
number of people that made this vaccine get to the
finish line and have the impact it's gonna have.
484
00:40:25,440 --> 00:40:30,480
I think it's time to get into the science of
malaria. But before we move on, I'll just,
485
00:40:30,480 --> 00:40:37,120
my reflection on this segment, is there gonna
be a lot of people listening who - basically
486
00:40:37,120 --> 00:40:44,160
science nerds - who sometimes it may feel like
the big things left to do in science while they're
487
00:40:44,160 --> 00:40:49,040
all behind us. That's why Saloni and Jacob talk
about Gaston Ramon. You know, we've already had
488
00:40:49,040 --> 00:40:56,080
all these antibiotics invented. Oh, well and so,
wouldn't it have been cool to live back then and.
489
00:40:56,080 --> 00:41:00,400
I think that's entirely the wrong orientation.
You know, there are people like Katharine Collins,
490
00:41:00,400 --> 00:41:05,920
who in 2010 to 2014, invent entirely new
vaccines that are now gonna be used by millions
491
00:41:05,920 --> 00:41:14,400
of children. And yet, and she is right here. We
got to talk to her right now. And you can too!
492
00:41:14,400 --> 00:41:20,480
You can work on important problems and there
are many people who can benefit! And it's just,
493
00:41:20,480 --> 00:41:25,280
it's almost scary how sensitive to
particular scientists at particular
494
00:41:25,280 --> 00:41:28,880
times a lot of this stuff is,
and it's very inspiring too.
495
00:41:28,880 --> 00:41:32,560
So, Katharine, thank you so much for joining us.
496
00:41:32,560 --> 00:41:36,160
Great to be here.
497
00:41:39,120 --> 00:41:43,040
All right, so how come it took so
long to develop a malaria vaccine?
498
00:41:43,040 --> 00:41:49,760
And why are malaria vaccines so much harder to
develop than vaccines against other diseases?
499
00:41:49,760 --> 00:41:53,360
Malaria is caused by a parasite, which is
quite different to a bacteria or a virus,
500
00:41:53,360 --> 00:41:57,280
it's a lot more complex. And the malaria
parasite actually moves- it has a really
501
00:41:57,280 --> 00:42:00,560
complicated lifecycle, and it moves
through at least three different stages.
502
00:42:00,560 --> 00:42:05,440
So it's first injected into the body by the
mosquito, and then travels from your skin into the
503
00:42:05,440 --> 00:42:10,560
liver. It develops in the liver for about seven
days and then bursts out into your red blood cells
504
00:42:10,560 --> 00:42:17,120
in your bloodstream and it invades your red blood
cells. The symptoms are caused by the parasites
505
00:42:17,120 --> 00:42:22,800
invading your red blood cells and then destroying
them, and then it does this many times. Each cycle
506
00:42:22,800 --> 00:42:27,040
it produces many more parasites and so it invades
many more red blood cells and that's what causes
507
00:42:27,040 --> 00:42:34,880
the anemia. And then the parasites within the
red blood cell, those infected red blood cells,
508
00:42:34,880 --> 00:42:39,040
can adhere to different tissues and that can
cause problems for different organs as well.
509
00:42:39,040 --> 00:42:44,000
I read that if just a single
parasite makes it to the liver,
510
00:42:44,000 --> 00:42:46,240
it can cause an infection. Is that true?
511
00:42:46,240 --> 00:42:50,640
Yeah, that's right. And that, I think that's the
really tough challenge with malaria, but you know,
512
00:42:50,640 --> 00:42:57,280
you can get hundreds or thousands of sporozoites
from one bite. But I think you - we don't think
513
00:42:57,280 --> 00:43:02,560
it's many thousands, and you could have some
immunity that gets rid of a lot of those,
514
00:43:02,560 --> 00:43:07,520
but just one has to get through the defenses, and
that gets into the liver, and then in the liver
515
00:43:07,520 --> 00:43:13,440
they actually replicate so that it doesn't stay as
one parasite. It turns into many, many merozoites,
516
00:43:13,440 --> 00:43:17,440
and they then burst out of the liver cell and
start invading blood cells. By the time you
517
00:43:17,440 --> 00:43:23,600
get to the blood, you've got many parasites again,
and very quickly, they replicate and produce more.
518
00:43:23,600 --> 00:43:30,080
That makes me think, both of the
vaccines are - the efficacy is much
519
00:43:30,080 --> 00:43:33,840
lower than many other vaccines.
But if I think about it this way,
520
00:43:33,840 --> 00:43:39,440
that they're trying to prevent even just
one parasite from getting to the liver,
521
00:43:39,440 --> 00:43:45,120
then from that perspective, it sounds like they're
actually really effective at doing that, at least.
522
00:43:45,120 --> 00:43:48,320
Yeah. Yeah, it's a very high bar. Exactly. Yeah.
523
00:43:48,320 --> 00:43:57,440
Well, that's terrifying. Just one parasite.
So all of that makes it much harder than,
524
00:43:57,440 --> 00:44:01,680
let's say, measles or flu,
which are caused by viruses
525
00:44:01,680 --> 00:44:10,000
and where the vaccines are produced
by killing or attenuating the virus.
526
00:44:10,000 --> 00:44:16,080
So there are many reasons that it's difficult
to make a vaccine against malaria parasites.
527
00:44:16,080 --> 00:44:21,360
First is this really complex life cycle
and then also the malaria parasite has
528
00:44:21,360 --> 00:44:25,360
been around since Egyptian times. So it's
evolved to evolve with the human immune
529
00:44:25,360 --> 00:44:30,160
system for a really long time, it's learnt
how to evade our immune responses really
530
00:44:30,160 --> 00:44:34,400
well. So every time our immune system is
managed to attack the malaria parasite,
531
00:44:34,400 --> 00:44:40,080
or find a good way to get rid of it, it's then
evolved another mechanism to keep surviving.
532
00:44:40,080 --> 00:44:43,840
There are lots and lots of redundant
proteins in the parasites. So you think
533
00:44:43,840 --> 00:44:46,560
you can block something that's important
and then it just switches on a different
534
00:44:46,560 --> 00:44:51,680
protein instead and uses that. That's been
one of the reasons it's been quite tricky.
535
00:44:51,680 --> 00:44:56,960
So the malaria parasite has a very
complicated lifecycle. Does it,
536
00:44:56,960 --> 00:45:03,120
when it goes through these different stages,
does it also change shape? What actually happens?
537
00:45:03,120 --> 00:45:09,760
Yeah, it looks completely different at each stage.
It starts with what we call a sporozoite that
538
00:45:09,760 --> 00:45:13,920
looks like a little eyelash when you look
under the microscope, it's a curve shape.
539
00:45:13,920 --> 00:45:19,200
Then when it invades the red blood cell, it's
called a merozoite; it's like a round, almost
540
00:45:19,200 --> 00:45:25,520
cone shape. But not only does it look different,
but it has different proteins on the surface. So
541
00:45:25,520 --> 00:45:30,160
a vaccine that works against one stage isn't
necessarily gonna work against another stage.
542
00:45:30,160 --> 00:45:34,160
Right. And that's one thing that's
hard about developing a vaccine. Like,
543
00:45:34,160 --> 00:45:37,840
how do you pick which protein
to use in the vaccine?
544
00:45:37,840 --> 00:45:42,320
Yeah, absolutely. Yeah. You know, the approach
is normally to look for a protein that's really
545
00:45:42,320 --> 00:45:47,600
important. So you find out something that's
probably something that's involved for an invasion
546
00:45:47,600 --> 00:45:53,040
or adhesion. So people would look at knocking
out different proteins and seeing whether they're
547
00:45:53,040 --> 00:45:57,520
critical for development. If you find something
that's essential, then that's also gonna be a
548
00:45:57,520 --> 00:46:03,760
good target. And the other way is that people
look for what's most abundant on the parasite,
549
00:46:04,480 --> 00:46:10,400
or the pathogen in general, but that can often be
a decoy. That's an interesting one. Like sometimes
550
00:46:10,400 --> 00:46:15,360
the things that were abundant on the surface
are there to misdirect the immune response.
551
00:46:15,360 --> 00:46:19,680
Okay. So you're taking these samples
from mice and you're learning a lot,
552
00:46:19,680 --> 00:46:27,920
it sounds like, from mice. So firstly,
thank you to our mouse brethren. And Saloni,
553
00:46:27,920 --> 00:46:34,320
I know that you have written a lot about,
in one of my favorite pieces that I read
554
00:46:34,320 --> 00:46:39,680
two years ago was about the invention of the
malaria vaccine. And you wrote about how mice
555
00:46:39,680 --> 00:46:46,720
were originally domesticated in some sense, to
be models for malaria. So how did that work?
556
00:46:46,720 --> 00:46:56,640
It starts out before mice, I think there were
some animal models in the late 19th century,
557
00:46:56,640 --> 00:47:04,480
the first animal models for malaria were birds.
And the way that scientists proved that malaria
558
00:47:04,480 --> 00:47:12,720
was spread by mosquitoes, was by using sparrows
and infecting them with the blood of an infected
559
00:47:12,720 --> 00:47:19,680
human, and seeing whether it would transmit.
And I think it seemed like there were some,
560
00:47:19,680 --> 00:47:23,680
there were a bunch of different birds that
could get infected by malaria, but they just
561
00:47:23,680 --> 00:47:29,200
didn't translate that well to what would happen
in humans? So people tried developing drugs,
562
00:47:29,200 --> 00:47:36,000
like testing new drugs, in bird malaria, and they
seemed to work there, but in humans they didn't;
563
00:47:36,000 --> 00:47:40,880
they caused various side effects. And so
they were trying to find different models.
564
00:47:40,880 --> 00:47:47,120
There are also two other types of
models used in between. One was monkeys;
565
00:47:47,120 --> 00:47:53,600
monkeys are really expensive and difficult
to work with. And then the other was humans,
566
00:47:53,600 --> 00:48:02,800
right? Because in the 1920s, if I remember
right, humans were used as a model to study
567
00:48:02,800 --> 00:48:09,840
malaria because people with syphilis could
be treated by infecting them with malaria,
568
00:48:09,840 --> 00:48:16,720
because the bacteria doesn't survive after
the fevers that are caused by malaria.
569
00:48:16,720 --> 00:48:23,680
It's a bit like solving your aching thumb
by chopping it off to me, but, okay.
570
00:48:23,680 --> 00:48:26,640
Would you rather get syphilis or malaria?
571
00:48:26,640 --> 00:48:35,840
Ah, the eternal question. And my answer is
I'm glad that we're in the 21st century.
572
00:48:35,840 --> 00:48:39,840
Syphilis seems like it was
really scary before antibiotics.
573
00:48:39,840 --> 00:48:40,720
Yeah.
574
00:48:40,720 --> 00:48:43,280
Especially if you got neurosyphilis.
575
00:48:43,280 --> 00:48:48,560
Yeah. The bacteria would worm its way up into
your brain and stick around for years or decades.
576
00:48:48,560 --> 00:48:52,960
I've been to a medical museum in
London called the Hunterian Museum,
577
00:48:52,960 --> 00:48:59,440
and they have exhibits of people
who had syphilis at the time,
578
00:48:59,440 --> 00:49:05,760
and their skulls are filled with holes
from the infection. It's very scary.
579
00:49:05,760 --> 00:49:09,760
Well, that's a wonderful tangent,
but I was wondering about,
580
00:49:09,760 --> 00:49:12,240
I was wondering if we could talk more about mice.
581
00:49:12,240 --> 00:49:20,080
Right. Okay, so mice, so we have the bird models
that aren't great. You have the monkey models that
582
00:49:20,080 --> 00:49:28,080
are really expensive, and the human models, which
once you could treat syphilis with antibiotics,
583
00:49:28,080 --> 00:49:35,200
there was no longer an audience of people
who were interested in being infected with
584
00:49:35,200 --> 00:49:41,680
malaria deliberately. So the next
question was, let's try to find a
585
00:49:41,680 --> 00:49:47,200
different animal model. Let's try to find
a rodent that can be infected by malaria.
586
00:49:47,200 --> 00:49:54,800
And I think it took quite a while to find any
rodents that were infected by malaria. There
587
00:49:54,800 --> 00:50:02,000
were two researchers that finally figured it out.
I think they were two Belgian researchers who
588
00:50:02,000 --> 00:50:10,480
were in the Congo, and they were doing tests
to see which animals mosquitoes had bitten,
589
00:50:10,480 --> 00:50:18,160
and that ruled out various animals nearby and
it didn't rule out rodents. So they thought
590
00:50:18,160 --> 00:50:23,280
maybe there's something here, and they continued
trying to look for rodents that were infected by
591
00:50:23,280 --> 00:50:29,920
malaria. And eventually they found a thicket rat
(Grammomys dolichurus) that was infected with it.
592
00:50:29,920 --> 00:50:37,840
This thicket rat was infected by a different
strain of malaria called Plasmodium berghei,
593
00:50:37,840 --> 00:50:45,120
and that seems to be much more - like that's just
much easier to work with. I think at first, they
594
00:50:45,120 --> 00:50:53,520
also, they couldn't replicate the whole lifecycle
of the parasite in those thicket rats, because
595
00:50:53,520 --> 00:50:59,360
there were certain stages of the parasite's
lifecycle that needed a cooler temperature.
596
00:50:59,360 --> 00:51:06,000
So when I was reading about this, it seemed like
it took 16 years for them to work that out. It was
597
00:51:06,000 --> 00:51:15,120
several things. So the original research was just
post World War II and then in the 1950s, various
598
00:51:15,120 --> 00:51:23,040
countries did large-scale malaria elimination
programs and cut down on malaria research.
599
00:51:23,040 --> 00:51:28,080
And so all the people who were working on that
stopped working on, or many of them did, stopped
600
00:51:28,080 --> 00:51:35,920
working on it, and then only then got interested
again in it during the Vietnam War. So I think it
601
00:51:35,920 --> 00:51:46,400
was like partly that and partly just, historical
contingency of which parasite they discovered. And
602
00:51:46,400 --> 00:51:53,520
did they look at their own lab notes from 16 years
ago to see what the temperatures were in that
603
00:51:53,520 --> 00:52:01,840
forest where they found the first malaria infected
rats. Goes to show how important lab notes are.
604
00:52:01,840 --> 00:52:04,080
Sounds like mice can tell you something, and took
605
00:52:04,080 --> 00:52:09,760
a long time to get to a model that worked in
the lab. But they can't tell you everything,
606
00:52:09,760 --> 00:52:13,840
'cause mice aren't humans, and
they might mislead you sometimes.
607
00:52:13,840 --> 00:52:16,720
A mouse has never told me anything.
608
00:52:16,720 --> 00:52:22,320
Speak for yourself. Well, I mean,
that brings me onto a question I have,
609
00:52:22,320 --> 00:52:26,720
which is: are mice enough?
If not, what's the next step?
610
00:52:26,720 --> 00:52:32,880
Well, so you could use non-human primates, but
they aren't the perfect model for malaria. There's
611
00:52:32,880 --> 00:52:38,160
only one that gets infected, that could
be affected with human malaria parasites,
612
00:52:38,160 --> 00:52:42,480
and so none of the models are perfect. So people
don't often do a lot of non-human primate work,
613
00:52:42,480 --> 00:52:48,240
but they can be used to answer specific questions.
So then your next model is obviously humans.
614
00:52:48,240 --> 00:52:49,920
Mm-hmm.
615
00:52:49,920 --> 00:52:54,000
And that makes sense because if you
want to make a vaccine for humans,
616
00:52:54,000 --> 00:52:58,320
you probably wanna test it on humans.
617
00:52:58,320 --> 00:53:03,040
Okay. So we're segueing to humans. How did that
begin? What were the first experiments in humans?
618
00:53:03,040 --> 00:53:09,280
So the first ones were the ones that were
treatments for syphilis in the 1910s to
619
00:53:09,280 --> 00:53:16,400
forties. And then when penicillin was developed,
it wasn't necessary anymore. But then, after that,
620
00:53:16,400 --> 00:53:24,960
there were various experiments in prisoners in
different parts of the US, I think. And what was
621
00:53:24,960 --> 00:53:30,160
interesting to me when I was reading about this
was that - so the prisoners were volunteering for
622
00:53:30,160 --> 00:53:35,520
these experiments, but some of the prisoners were
not just subjects in the experiments. Some of them
623
00:53:35,520 --> 00:53:41,920
were actually technicians and researchers,
who helped in the experiments as well.
624
00:53:41,920 --> 00:53:49,600
And one of the most famous ones is Nathan
Leopold. Do you know, do you recognize that name?
625
00:53:49,600 --> 00:53:51,200
Not me.
626
00:53:51,200 --> 00:53:59,120
So he was a - I know this because of a film that
was inspired by his life. He was a murderer who
627
00:53:59,120 --> 00:54:07,120
murdered a friend, I think, a classmate of his.
So with a friend of his, they both kidnapped and
628
00:54:07,120 --> 00:54:11,280
murdered one of their classmates while they
were students at the University of Chicago.
629
00:54:11,920 --> 00:54:16,320
And while they were serving their sentences,
630
00:54:16,320 --> 00:54:23,760
Nathan Leopold, one of them, enrolled in one of
the malaria research studies. And after that,
631
00:54:23,760 --> 00:54:31,360
he then became a technician, he started doing -
like he was actually operating research as well.
632
00:54:31,360 --> 00:54:38,480
And the reason that I know this is because that
story inspired the Alfred Hitchcock film Rope,
633
00:54:38,480 --> 00:54:40,160
if you've seen that. Have you seen that?
634
00:54:40,160 --> 00:54:41,760
I have not seen that.
635
00:54:41,760 --> 00:54:48,800
It's a very good movie where, I mean, it's the
same-ish story. They've kind of changed what
636
00:54:48,800 --> 00:54:56,320
actually happened. But in the film, these two
students decide to kidnap and kill one of their
637
00:54:56,320 --> 00:55:05,680
classmates for fun, essentially. And then they
store him in a, what is it called? Like a box in
638
00:55:05,680 --> 00:55:14,560
their apartment. And they then host a party just
hours after this murder, to basically show the
639
00:55:14,560 --> 00:55:21,040
fact that they could get away with it. And the
whole film was taken in 10 shots, like 10 long
640
00:55:21,040 --> 00:55:27,200
segments that are just stitched together. And it's
an incredible film. Like very, very well made.
641
00:55:27,200 --> 00:55:30,400
Wow. Okay, so...
642
00:55:30,400 --> 00:55:38,480
So how does this relate to malaria?
Many prisoners would've been part
643
00:55:38,480 --> 00:55:46,000
of this malaria research in the mid
20th century, and they contributed
644
00:55:46,000 --> 00:55:51,840
to our understanding of various parts
of the transmission process, I think.
645
00:55:51,840 --> 00:55:57,360
And since then, we've continued studying malaria
in humans in a type of study called a challenge
646
00:55:57,360 --> 00:56:04,800
trial, where you deliberately infect volunteers
with mosquitoes with malaria. So I think in the
647
00:56:04,800 --> 00:56:12,560
past it was many mosquitoes per person and
now it's just five bites. Is that right?
648
00:56:12,560 --> 00:56:20,560
Yeah. I guess there was work to improve and
standardize the modern challenge trials.
649
00:56:20,560 --> 00:56:26,640
That's where they landed on five mosquito bites
that could reproducible infect the volunteers.
650
00:56:26,640 --> 00:56:32,240
So what happens in one of these experiments
do you sit with. Do you put your hand into
651
00:56:32,240 --> 00:56:36,960
a jar that's filled with mosquitoes
or what? What's the what's it like?
652
00:56:36,960 --> 00:56:42,480
No, the process is quite dull, actually. I guess
you normally have to travel to somewhere where
653
00:56:42,480 --> 00:56:47,600
there's a facility. And because these sort
of things do contain mosquitoes infected with
654
00:56:47,600 --> 00:56:52,560
malaria, they're usually under high containment,
so then the volunteers need to pass into a
655
00:56:52,560 --> 00:56:58,480
contained containment area, and then a cup is
often passed through a window into that room
656
00:56:58,480 --> 00:57:04,000
and they have a cup - it's like a coffee cup -
and it has gauze on the top and the mosquitoes
657
00:57:04,000 --> 00:57:09,840
will be inside. The lid will all be taped shut
so they can't escape, and then you place your arm
658
00:57:09,840 --> 00:57:15,920
on top of the cup and allow the five mosquitoes
to bite you and say, a few minutes for feeding.
659
00:57:15,920 --> 00:57:19,320
And then they'll have a look and see how
many of those mosquitoes have fed on you.
660
00:57:19,320 --> 00:57:20,191
So what they do is they take the cup
of mosquitoes, they then look at them,
661
00:57:20,191 --> 00:57:22,703
each mosquito individually under the microscope.
You can see whether it's blood fed, because it's
662
00:57:22,703 --> 00:57:23,105
got blood in its abdomen, in its belly. Then if
it's got blood in the belly, then look at the
663
00:57:23,105 --> 00:57:23,202
salivary glands and check that it had sporozoites
in the salivary glands. And so you're looking,
664
00:57:23,202 --> 00:57:23,893
five mosquitoes in that cup that fed. But so
they count up how many did feed, then they'll
665
00:57:27,413 --> 00:57:29,360
put more mosquitoes in a cup. So if you only
need one more infected bite, they'll put one more
666
00:57:29,360 --> 00:57:30,480
mosquito in, and then you can be bitten by that
mosquito. If that one doesn't bite you, then they
667
00:57:30,480 --> 00:57:31,680
take that one out, put another one in
until you've had five infected bites.
668
00:57:31,680 --> 00:57:39,360
Oh, I see. That's probably the most
disgusting coffee cup I've heard of.
669
00:57:39,360 --> 00:57:44,160
Not so tasty. These, these days, are the
people who are putting their arms out,
670
00:57:44,160 --> 00:57:47,840
are they mostly undergrads somewhere
or, yeah, what, who are the volunteers?
671
00:57:47,840 --> 00:57:52,720
I think it depends where you do the trials. I
think in Oxford it's typically lots of students,
672
00:57:52,720 --> 00:58:00,880
but other people as well. But you, the students
are often quite willing to get involved.
673
00:58:00,880 --> 00:58:02,880
Legends.
674
00:58:02,880 --> 00:58:09,920
I saw a picture where it wasn't a coffee
cup, but it was a cup noodle box container.
675
00:58:09,920 --> 00:58:14,480
Yeah or soup. And they're often called, used as
soup cups. They're like, or ice cream containers,
676
00:58:14,480 --> 00:58:18,480
they're that kind of large, larger size that
would be used. That's usually used to hold
677
00:58:18,480 --> 00:58:21,440
a lot more mosquitoes. It would've
been a different study, probably.
678
00:58:21,440 --> 00:58:22,480
Oh, I see.
679
00:58:23,040 --> 00:58:28,400
So you, in those challenge models, you
are giving some of the students or other
680
00:58:28,400 --> 00:58:33,760
volunteers injections of vaccine, some of
them placebo, and then they're getting bitten.
681
00:58:33,760 --> 00:58:35,440
Exactly. That's right. Yeah.
682
00:58:35,440 --> 00:58:38,240
Okay. And then what do you, how do you figure out
683
00:58:38,240 --> 00:58:41,440
the truth afterwards? You're just
seeing which one of them faint, or?
684
00:58:41,440 --> 00:58:49,600
Once you've been challenged, you start following
them up a couple of days later. So the parasites
685
00:58:49,600 --> 00:58:52,880
will be in the liver for seven days. You
don't have to monitor them too carefully
686
00:58:52,880 --> 00:58:58,000
in the beginning, but you still monitor them and
check the parasites haven't got into the liver,
687
00:58:58,000 --> 00:59:03,280
into the blood from the liver. And
then you are monitoring quite closely
688
00:59:03,280 --> 00:59:08,320
from liver emergence. So once the parasites are
entering the blood or you're expecting them to,
689
00:59:08,320 --> 00:59:11,840
you can see them once or twice a day,
up to twice a day, take their blood.
690
00:59:11,840 --> 00:59:14,400
You can look under the microscope for
the parasites, see if they've got the
691
00:59:15,120 --> 00:59:19,600
parasites in their blood, and you can
also do molecular diagnostics as well,
692
00:59:19,600 --> 00:59:24,240
like PCR to look - it's a much more
sensitive method. So you can detect
693
00:59:24,240 --> 00:59:28,560
the parasites in the blood before they will
make the people sick. And so you can treat
694
00:59:28,560 --> 00:59:34,640
them quite quickly and then you'll know which
volunteers have been protected and which haven't.
695
00:59:34,640 --> 00:59:41,520
That's very cool. And then now there are
methods that are beyond mosquito bites.
696
00:59:41,520 --> 00:59:47,760
People directly inject volunteers
with the parasite, is that right?
697
00:59:47,760 --> 00:59:52,080
Yeah, there's a couple of models. So
the other models you would inject either
698
00:59:52,080 --> 00:59:56,320
cryopreserved sporozoites, that's that
first stage that goes into the liver.
699
00:59:56,320 --> 01:00:00,880
You can inject those intravenously, you
can ship those anywhere in the world to
700
01:00:00,880 --> 01:00:05,600
do that type of study. The other model
is injecting blood stage parasites. So
701
01:00:05,600 --> 01:00:08,640
both of these are greats and they
can answer different questions.
702
01:00:08,640 --> 01:00:16,080
And these two vaccines, the RTS,S and
R21, are for the first stage. So you'd
703
01:00:16,080 --> 01:00:21,040
want to be able to test it against the
natural infection with the mosquito bite.
704
01:00:21,040 --> 01:00:22,000
Yeah, definitely.
705
01:00:22,000 --> 01:00:23,840
Saloni, I've got a question for you.
706
01:00:23,840 --> 01:00:26,000
Oh, what's the question?
707
01:00:26,000 --> 01:00:29,280
Would you have volunteered for one
of these human challenge trials?
708
01:00:29,280 --> 01:00:35,840
I was thinking about this back when you asked
who was volunteering in the studies because as
709
01:00:35,840 --> 01:00:42,400
I have described in the first episode we did,
I once volunteered for an HIV vaccine trial,
710
01:00:42,400 --> 01:00:48,480
phase one trial. And I enjoyed
it and I think I probably would.
711
01:00:48,480 --> 01:00:52,960
I think the difficulty is that back when
I did that, I was a student and I was very
712
01:00:52,960 --> 01:00:57,360
bored and I didn't have anything to do in my
free time anyway and I didn't have a social
713
01:00:57,360 --> 01:01:03,520
life. And now I have a lot of stuff going on
in my life, like I just have a lot of work.
714
01:01:03,520 --> 01:01:08,000
By the way... congratulations.
715
01:01:08,000 --> 01:01:08,880
Thank you.
716
01:01:09,440 --> 01:01:13,280
Me, I'm still alone, but I'll get there.
717
01:01:13,280 --> 01:01:19,200
But I was thinking like, there are lots
of different types of diseases that you
718
01:01:19,200 --> 01:01:23,040
might do a challenge trial for, right?
Like you could do one for rhinovirus or
719
01:01:23,040 --> 01:01:29,040
like flu or cholera or I don't know,
what else is there - Shigella maybe,
720
01:01:29,040 --> 01:01:34,080
or something like that. And all of these
sound very unappetizing to me. Like,
721
01:01:34,080 --> 01:01:39,200
I wouldn't wanna do a challenge trial for any
of those. Like the flu, the respiratory ones,
722
01:01:39,200 --> 01:01:45,808
I'm like, that's just boring and someone else
is gonna do them anyway. Probably the, that's -
723
01:01:45,808 --> 01:01:50,080
Amazing. I'm not gonna do that one.
It's boring. I want something harder!
724
01:01:50,080 --> 01:01:53,920
Right. And then the other,
like cholera and shigella,
725
01:01:53,920 --> 01:02:01,120
I mean, diarrhea... I don't want, that
sounds horrible. And also I feel like
726
01:02:01,120 --> 01:02:06,560
I'm quite small and if I lose too much
weight, there'll be none of me left,
727
01:02:06,560 --> 01:02:13,760
and so I can't do that one. So what I would
do is a more dangerous pathogen, I think.
728
01:02:13,760 --> 01:02:16,301
Okay, nice. Is malaria dangerous enough for you?
729
01:02:16,301 --> 01:02:18,240
That would make it worth it. I think so, yeah.
730
01:02:18,240 --> 01:02:19,600
Okay. Even though malaria -
731
01:02:19,600 --> 01:02:20,880
Even though it's treatable and stuff.
732
01:02:20,880 --> 01:02:26,480
It's treatable. Yeah. I mean, just in case
listeners are thinking about it themselves
733
01:02:26,480 --> 01:02:31,440
and concerned; in the diarrhea ones, they
do treat you. They don't just leave you,
734
01:02:31,440 --> 01:02:36,880
they give you antibiotics. But yeah,
those in order to get more of a signal,
735
01:02:36,880 --> 01:02:40,960
they don't treat you in, within an
hour, they'll probably you within 12
736
01:02:40,960 --> 01:02:46,000
hours or something. So it's a - it's not, you
gotta go through some pain to get the gain.
737
01:02:46,000 --> 01:02:52,720
Well, I read that with the cholera vaccine
challenge trials some people... actually,
738
01:02:52,720 --> 01:02:54,800
you know what? I'm not gonna finish that sentence.
739
01:02:54,800 --> 01:02:56,280
Oh -
740
01:02:58,400 --> 01:03:01,200
It was about how much diarrhea
they had. And you know what? I
741
01:03:01,200 --> 01:03:03,600
don't actually wanna give people that image.
742
01:03:03,600 --> 01:03:09,440
That's.. you know what, Saloni?
I think they've got it now.
743
01:03:09,440 --> 01:03:14,240
So my question for malaria, Katharine, how
sick do you get? Do you get sick at all or
744
01:03:14,240 --> 01:03:19,600
do you get treated as soon as there's any risk
of sickness or? What if you're in, what happens?
745
01:03:20,400 --> 01:03:25,280
I guess the idea is that they treat you before
you develop any real symptoms. So you probably
746
01:03:25,280 --> 01:03:30,880
start to feel a bit fluey. You may get a headache,
but because they're monitoring your parasitemia
747
01:03:30,880 --> 01:03:36,240
so closely, the plan is to treat you before
you get any really uncomfortable symptoms. By
748
01:03:36,240 --> 01:03:41,040
the time you get treatment, you could have
some symptoms. I think people do typically
749
01:03:41,040 --> 01:03:47,360
get symptoms. They feel rough for a day or
two, but that's hopefully the extent of it.
750
01:03:47,360 --> 01:03:50,240
I think that's kind of cool. Yeah, I
would do it. I mean, I haven't done it,
751
01:03:50,240 --> 01:03:54,560
so you always have to take with a grain of
salt, whatever I say now. The issue, yeah,
752
01:03:54,560 --> 01:04:00,880
I tried to volunteer for a trial recently and
ended up getting swamped in the logistics. So
753
01:04:00,880 --> 01:04:06,160
your point Saloni, that it's harder once you
have a job? I've had that experience too.
754
01:04:06,160 --> 01:04:13,360
It also depends where you live, whether there are
trials around you that are convenient that you can
755
01:04:13,360 --> 01:04:20,480
participate in. So it comes down to those aspects
as much as anything. But malaria sounds kind of
756
01:04:20,480 --> 01:04:24,320
fun. If you get, the drugs are great. You get,
if you get feel a little bit sick, that will make
757
01:04:24,320 --> 01:04:29,680
me feel like I've done something for humanity and
then I get treated, I'm up for that. Sounds good.
758
01:04:29,680 --> 01:04:34,800
And also you get to live in a cool
quarantine hotel for a bit. No?
759
01:04:34,800 --> 01:04:35,917
No, because -
760
01:04:35,917 --> 01:04:35,920
No?
761
01:04:35,920 --> 01:04:40,320
It's safe to walk outside. In England, right?
There's no, there's no mosquitoes that bite you.
762
01:04:41,760 --> 01:04:44,960
So you are infected and then they're just like,
763
01:04:44,960 --> 01:04:50,000
go on with your life. Yeah. And
you just feel sick at home instead?
764
01:04:50,000 --> 01:04:53,520
Yeah. They give you a little card to
put in your wallet, which tells people
765
01:04:53,520 --> 01:04:56,320
what you have and what you need to be
treated with in case something happens.
766
01:04:56,320 --> 01:04:56,960
Oh, really?
767
01:04:56,960 --> 01:05:01,440
Okay. I'm not volunteering for this thing.
768
01:05:01,440 --> 01:05:05,440
Emergencies, like if you ended up in hospital
from a car crash or something, they would know
769
01:05:05,440 --> 01:05:08,720
that they should probably give you
antimalarials now. The study's over.
770
01:05:08,720 --> 01:05:12,240
No, I thought, I thought you'd be in
a little quarantine hotel. I thought
771
01:05:12,240 --> 01:05:15,840
it was like a mini vacation but you're sick.
772
01:05:15,840 --> 01:05:20,720
No, I think maybe they do it differently
in different places. So it depends maybe
773
01:05:20,720 --> 01:05:26,720
what type of trial you are in. So for the drug
trials with malaria, because they actually let
774
01:05:26,720 --> 01:05:32,000
you develop parasitemia to a certain level,
then they treat you. And then they want to
775
01:05:32,000 --> 01:05:37,440
measure the clearance rate of the parasites.
So they want to sample you quite quickly and
776
01:05:37,440 --> 01:05:43,200
frequently after treatment. So for those, they
do often do inpatient for your convenience,
777
01:05:43,200 --> 01:05:48,000
then they let you go once you are treated,
so it could be just a couple of days.
778
01:05:48,000 --> 01:05:53,040
I think I'm thinking of the respiratory
virus challenge trials where, because
779
01:05:53,040 --> 01:05:56,560
you could transmit it to someone
else, they keep you in a facility.
780
01:05:56,560 --> 01:06:01,920
Diarrhea as well, for the shigella one they
keep you in. Yeah. I realized Katharine in
781
01:06:01,920 --> 01:06:06,640
that description though, one of the other
reasons why people might not want to do it,
782
01:06:06,640 --> 01:06:12,000
which is you're getting pinpricked constantly
'cause people are taking a lot of blood samples.
783
01:06:12,000 --> 01:06:19,680
So that's if you wanna get over needle
phobia via exposure therapy, go for it!
784
01:06:23,760 --> 01:06:29,920
I feel like the way to - Exposure
therapy is supposed to give you
785
01:06:29,920 --> 01:06:33,200
like a mild version where it's like,
oh, nothing actually happens when you
786
01:06:33,200 --> 01:06:39,040
get injections. This seems like
it would actually scare you more!
787
01:06:39,040 --> 01:06:47,120
Well, I did exposure therapy and nearly died.
788
01:06:47,120 --> 01:06:49,440
Would you participate in the challenge trial?
789
01:06:50,080 --> 01:06:54,000
I would love to, but I really hate needles.
790
01:06:54,000 --> 01:06:56,240
Oh, there we go! There we go!
791
01:06:56,240 --> 01:06:59,840
It's kind of ironic for a vaccine developer.
792
01:06:59,840 --> 01:07:02,000
That's so funny.
793
01:07:05,200 --> 01:07:08,320
I'm terrified of getting vaccines. When
I have, when I go to get a vaccine,
794
01:07:08,320 --> 01:07:12,720
I have to lie down to have a vaccine, I
have to lie down with the blood taken,
795
01:07:12,720 --> 01:07:16,720
as otherwise I might faint. I think I have
fainted in the past, that's the problem.
796
01:07:16,720 --> 01:07:17,280
Oh, wow.
797
01:07:18,000 --> 01:07:24,560
And so, as you mentioned we take blood in these
challenge trials, 10 to 15 times depending on
798
01:07:24,560 --> 01:07:30,960
when you get malaria. So I just couldn't,
I couldn't cope with that. Unfortunately.
799
01:07:30,960 --> 01:07:35,680
We must know our limits. Okay. So how come
that's not enough? Or is it enough? So
800
01:07:35,680 --> 01:07:40,160
let's say you've taken a malaria vaccine through
human challenge trials. You ready to license it,
801
01:07:40,160 --> 01:07:45,040
roll it out across different countries or
not? I know the answer, but I'm curious.
802
01:07:45,040 --> 01:07:50,000
Well, obviously no, I guess that's not the target
population. So you still need to find out if your
803
01:07:50,000 --> 01:07:55,280
vaccine's gonna work in the people that it's
intended for, which would be children in Africa.
804
01:07:55,280 --> 01:07:57,920
Well, we have some vaccines
that are approved just from
805
01:07:57,920 --> 01:08:01,040
challenge trials. Right? Like the typhoid vaccine.
806
01:08:01,040 --> 01:08:06,240
Yeah, that's right. Yeah, I think when the
trial isn't feasible to be done in the target
807
01:08:06,240 --> 01:08:11,680
population, there's good arguments to try and
get that efficacy signal from a challenge trial,
808
01:08:11,680 --> 01:08:15,520
and then they still need to get
your safety data from the target
809
01:08:15,520 --> 01:08:18,320
population that you're gonna
use the vaccine in as well.
810
01:08:18,320 --> 01:08:22,800
Okay. So we've talked about the second
malaria vaccine, and we are talking about
811
01:08:22,800 --> 01:08:28,880
the animal models and the human challenge
models for vaccines in general. Saloni,
812
01:08:28,880 --> 01:08:35,360
since you've written about the history of malaria,
I'd love to hear, if you're willing, what was
813
01:08:35,360 --> 01:08:41,200
the first malaria vaccine development timeline
like? What were the steps there? What happened?
814
01:08:41,200 --> 01:08:47,920
I love how we've gone through this backwards, like
we're doing the Star Wars prequels or something.
815
01:08:47,920 --> 01:08:50,160
But more entertaining.
816
01:08:52,160 --> 01:08:57,680
Well, I guess it's a long story. So I think I
probably wanna start with a quick summary of
817
01:08:57,680 --> 01:09:04,400
the whole development. I first got interested in
this topic when I was reading about the news of
818
01:09:04,400 --> 01:09:13,760
the malaria vaccine being rolled out in 2021,
and I wanted to write a blog post about it.
819
01:09:14,880 --> 01:09:20,320
So I was starting to write this blog post, and one
of the first things that I learned was that it was
820
01:09:20,320 --> 01:09:26,480
actually developed in the '90s. And it really
kind of shocked me and I was just thinking:
821
01:09:26,480 --> 01:09:32,480
what went wrong? Like, what happened? Why
was it, why it didn't only get released now,
822
01:09:32,480 --> 01:09:38,880
if it was developed so long ago? And
a lot of my interest just stemmed from
823
01:09:38,880 --> 01:09:46,160
that curiosity and frustration, with
how things could have taken so long.
824
01:09:46,160 --> 01:09:53,280
The short version is that I think a lot of it
is because of a lack of funding, infrastructure,
825
01:09:53,280 --> 01:10:02,640
and in some cases, also the regulatory changes
and standards that there were. But I think the
826
01:10:02,640 --> 01:10:12,240
broader version is really, you know, this malaria
vaccine essentially came out of research from the
827
01:10:12,240 --> 01:10:23,520
US Army. In the 1950s, almost every country
was affected by malaria, and they used, there
828
01:10:23,520 --> 01:10:30,400
were large scale malaria eradication programs in
the 1950s, mostly using insecticides like DDT.
829
01:10:31,840 --> 01:10:34,576
And those were very effective, like a lot of high
830
01:10:34,576 --> 01:10:42,320
income countries eliminated malaria in the
1950s with DDT and other control efforts.
831
01:10:42,320 --> 01:10:48,480
And funding also declined, so there was no more
reason for a lot of high income countries to do
832
01:10:48,480 --> 01:10:55,360
research on malaria, and a lot of the researchers
who were previously doing it became operators and
833
01:10:55,360 --> 01:11:03,440
managers of this eradication program. So funding
for research and development massively contracted,
834
01:11:03,440 --> 01:11:12,400
and that kind of stayed that way until really
the 1960s, when the Vietnam War was happening,
835
01:11:12,400 --> 01:11:18,400
and the US Army was then once again facing
malaria in Southeast Asia. But by then it was
836
01:11:18,400 --> 01:11:23,440
kind of drug resistant malaria. So there was
once again, this need for research trying to
837
01:11:23,440 --> 01:11:30,000
develop new drugs that were effective against drug
resistant malaria, but also potentially vaccines.
838
01:11:30,000 --> 01:11:36,960
And so some researchers started working on
this program to try to develop a malaria
839
01:11:36,960 --> 01:11:44,240
vaccine. And their names were Ruth Nussenzweig,
Jerome Vanderberg and some of their colleagues.
840
01:11:44,240 --> 01:11:49,040
And what they did was, they first tried to
build a proof of concept of the vaccine,
841
01:11:49,040 --> 01:11:57,600
so let's see if you can protect mice by
infecting them first with a killed version
842
01:11:57,600 --> 01:12:03,360
of the parasite. If you protect them with this
killed version of the parasite, will they then
843
01:12:03,360 --> 01:12:08,160
be protected from another infection? And what
they found was that yes, you could do that.
844
01:12:08,160 --> 01:12:14,560
And, this eventually much later led to a different
type of vaccine, which we might come back to later
845
01:12:14,560 --> 01:12:23,920
on, but it's not really scalable. So the other
option is let's try to develop a subunit vaccine.
846
01:12:24,640 --> 01:12:32,000
From our previous episode on a history of vaccines
and Hepatitis B, basically the idea here is that,
847
01:12:32,000 --> 01:12:38,080
instead of using the whole organism, the whole
parasite as a vaccine, let's try to find a few
848
01:12:38,080 --> 01:12:43,280
components, or maybe the one component, that
is enough to stimulate an immune response.
849
01:12:43,280 --> 01:12:50,160
And so that's what they tried to find and
they sort of looked at these mice that they
850
01:12:50,160 --> 01:12:56,800
were protecting with this killed parasite and saw:
what are they generating antibodies against? What
851
01:12:56,800 --> 01:13:03,040
is their immune response reacting against?
And they found that that clustered around a
852
01:13:03,040 --> 01:13:10,320
protein called the circumsporozoite protein.
That protein, it turned out, was gonna be a
853
01:13:10,320 --> 01:13:17,440
very good candidate for a vaccine. That was
gonna be the main component of the vaccine.
854
01:13:17,440 --> 01:13:25,040
So the initial attempts were to use that protein
as the vaccine. If you remember back from our
855
01:13:25,040 --> 01:13:32,320
protein subunit vaccines episode, the Hepatitis
B one, often just using a single protein in a
856
01:13:32,320 --> 01:13:38,560
vaccine is not very effective. And the reason for
that is that, often when you have a whole pathogen
857
01:13:38,560 --> 01:13:42,400
being a vaccine, or when you're exposed to a
whole pathogen, there are many things about that
858
01:13:42,400 --> 01:13:48,560
pathogen that can stimulate your immune response.
Whereas when it's just one protein from that,
859
01:13:48,560 --> 01:13:54,080
that's often not enough for your immune system
to recognize that this is something that we need
860
01:13:54,080 --> 01:14:00,000
to react to. There are obviously lots of nuances
there, but that's kind of the simplified version.
861
01:14:00,000 --> 01:14:06,320
So this initial vaccine, just using that
one circumsporozoite, or CSP, protein,
862
01:14:06,320 --> 01:14:13,200
was not very effective. They only managed to
protect one volunteer out of six in their first
863
01:14:13,200 --> 01:14:21,760
study. The way that you improve that, is often
by adding an adjuvant. So an adjuvant boosts the
864
01:14:21,760 --> 01:14:27,920
immune response in some way, and so that's kind of
what they tried. They tried different adjuvants,
865
01:14:27,920 --> 01:14:34,160
they tried different formulations, and
eventually they created this formulation.
866
01:14:34,160 --> 01:14:38,560
And I forget what each of the letters
stands for. And this, the formulation
867
01:14:38,560 --> 01:14:45,040
was the RTS,S vaccine. And so Katharine,
what does, what is this formulation made of?
868
01:14:45,040 --> 01:14:49,920
So the formulation is made of parts of the
malaria parasite and the Hep B virus. So
869
01:14:49,920 --> 01:14:55,360
the R stands for the repeat region, which is
from the CS protein in the malaria parasite.
870
01:14:55,360 --> 01:14:59,120
The T is for the T cell epitopes
that are from the same protein,
871
01:14:59,120 --> 01:15:05,600
and the S is from the Hep B surface antigen,
and this is fused to that malaria protein.
872
01:15:05,600 --> 01:15:10,560
Then there's the excess Hep B surface antigen
I mentioned before that was needed for this to
873
01:15:10,560 --> 01:15:15,120
form a virus-like particle, and that's
the extra S so that makes the RTS,S.
874
01:15:17,040 --> 01:15:24,000
Unfortunately, by the '90s, there was no
longer interest in funding it from Vietnam War
875
01:15:24,000 --> 01:15:31,840
era army research anymore, and they couldn't
scale up and continue that research. So they
876
01:15:31,840 --> 01:15:38,880
only found this adjuvant, that they ended
up using, in the nineties. So at that point,
877
01:15:38,880 --> 01:15:45,440
we have a possibly more effective vaccine
and they did another challenge trial to
878
01:15:45,440 --> 01:15:49,520
see how effective that would be.
This time it was more effective,
879
01:15:49,520 --> 01:15:56,320
it was six out of seven people in the challenge
trial that were protected from further infections.
880
01:15:56,320 --> 01:16:02,000
And again, this, a seven person study
sounds extremely small and it is,
881
01:16:02,000 --> 01:16:11,920
but that was one - this is a preliminary, pilot
type of study, so this isn't really the real deal,
882
01:16:11,920 --> 01:16:17,520
but it is still much better than
any other study had shown so far.
883
01:16:17,520 --> 01:16:22,160
So this was a much more promising
candidate for further research.
884
01:16:22,160 --> 01:16:29,120
So what they did next was to do a field trial with
many more participants. So they ran a field trial
885
01:16:29,120 --> 01:16:36,080
in The Gambia with 300 men, they vaccinated
them with this candidate and with a placebo,
886
01:16:36,080 --> 01:16:41,360
and they looked at their rates of malaria
infection afterwards. And in the group
887
01:16:41,360 --> 01:16:48,400
that received the vaccine, they had a 34%
lower rate of malaria infections over the
888
01:16:48,400 --> 01:16:55,360
next four months. So that was the first
field trial, and that was done in 1998.
889
01:16:55,360 --> 01:17:04,080
And okay, this field trial looks not amazingly
effective, but still effective in a way that
890
01:17:04,080 --> 01:17:09,680
no other vaccine candidate had been up to
that point. And so the next step was really,
891
01:17:09,680 --> 01:17:16,640
let's try to get this into real, clinical trials
in the population that needs these vaccine,
892
01:17:16,640 --> 01:17:23,040
which are children. So they started with trials
in older children, who were 6 to 11 years old,
893
01:17:23,040 --> 01:17:28,240
and then younger children, who were 1 to 4
years old, and then finally infants. This
894
01:17:28,240 --> 01:17:36,160
idea is called age deescalation. Basically you're
testing it first in children who are least likely
895
01:17:36,160 --> 01:17:42,640
to be affected by potential side effects, and
then the infant group who are more vulnerable.
896
01:17:42,640 --> 01:17:51,200
You sort of wanna make sure that it works first in
adults, and then in children, and then in infants.
897
01:17:51,200 --> 01:17:58,880
But this process took a long time and they
struggled to find funding at every stage
898
01:17:58,880 --> 01:18:07,680
of the process from what I read, and also needed
to themselves set up clinical trial sites across
899
01:18:07,680 --> 01:18:15,120
Africa. Often there were just not clinics
with the expertise to run clinical trials,
900
01:18:15,120 --> 01:18:21,120
or the equipment to do testing and things
like that, and the researchers themselves
901
01:18:21,120 --> 01:18:26,720
had to fund some of that work, so it was a
very long process. And then it eventually
902
01:18:26,720 --> 01:18:34,160
finished in 2015, the phase three trials
ended at that point. That is, I think,
903
01:18:34,160 --> 01:18:39,600
much longer than the research process
that we often have for vaccines today.
904
01:18:39,600 --> 01:18:44,080
Though, luckily, I'm sure that
meant it got approved in 2015.
905
01:18:44,080 --> 01:18:45,280
No!
906
01:18:45,280 --> 01:18:49,280
No. What happened then?
907
01:18:49,280 --> 01:18:57,440
What happened then? Well, in 2015, the phase
three results came in and the European Medicines
908
01:18:57,440 --> 01:19:05,680
Agency said, this looks safe and effective, but
the World Health Organization didn't recommend
909
01:19:05,680 --> 01:19:14,320
it for a large scale rollout. They asked for
more pilot studies before they would do that.
910
01:19:14,320 --> 01:19:20,880
And one of the reasons for that was that there
were some, in post hoc analyses of the data,
911
01:19:20,880 --> 01:19:26,720
they found higher rates of meningitis in
older children and higher rates of death
912
01:19:26,720 --> 01:19:35,760
in girls at two of the trial sites. And the World
Health Organization, if I understand correctly,
913
01:19:35,760 --> 01:19:40,320
didn't think that they were - those signs
were causally related to the vaccine,
914
01:19:40,320 --> 01:19:45,520
but they wanted it to be ruled out,
and so they asked for pilot studies.
915
01:19:45,520 --> 01:19:51,280
The pilot studies took around four years to
find funding for, and to get staffing for,
916
01:19:51,280 --> 01:19:58,160
and they finally launched in 2019. And then
another two years into the pilot studies,
917
01:19:58,160 --> 01:20:05,840
there was enough data for the Data Safety
Monitoring Board to look at the data, find no
918
01:20:05,840 --> 01:20:12,640
increased risk of these side effects, and then
finally clear the vaccine for the World Health
919
01:20:12,640 --> 01:20:22,640
Organization's endorsement in October, 2021. So
that is 23 years after the first field trials.
920
01:20:22,640 --> 01:20:25,680
The safety was one of the reasons,
but that wasn't the only reason,
921
01:20:25,680 --> 01:20:30,560
right? They, there was a lack of
confidence in how effective the
922
01:20:30,560 --> 01:20:37,680
vaccine was. So it wasn't the risk, it was
about the risk benefit analysis. You know,
923
01:20:37,680 --> 01:20:43,280
it was only 36% effective in those phase
three trials, and there was the safety signal.
924
01:20:43,280 --> 01:20:50,080
The RTS,S vaccine was going up for EMA and WHO
review in 2014, 2015. That was just about when
925
01:20:50,080 --> 01:20:56,240
you were finishing your PhD, working on the R21
vaccine. Katharine, so what was the feeling like
926
01:20:56,240 --> 01:21:02,400
in the malaria research community at that time?
Did people have conflicting and different views,
927
01:21:02,400 --> 01:21:08,000
and there was a lot of debate? Was there
consensus and surprise? What, what was it like?
928
01:21:08,000 --> 01:21:11,920
I think everybody was really hopeful that the
vaccine would get approved. I think there was
929
01:21:11,920 --> 01:21:16,720
definitely mixed opinions in the field
about whether a vaccine that showed such
930
01:21:16,720 --> 01:21:21,440
low efficacy in the phase three trial should
be rolled out and would actually be effective.
931
01:21:21,440 --> 01:21:26,320
So I think what was really important and really
key was the cost effectiveness modeling that was
932
01:21:26,320 --> 01:21:30,720
done with the data. And I think that was quite
pivotal. And in that it really showed that
933
01:21:30,720 --> 01:21:37,040
even a poorly effective vaccine or suboptimal
vaccine, most vaccines that have been used in
934
01:21:37,040 --> 01:21:42,480
children at the time had really high levels of
efficacy, like 80, 90%. So it was a completely
935
01:21:42,480 --> 01:21:47,200
uncharted territory. But the modeling showed that
even with this low level of efficacy, because
936
01:21:47,200 --> 01:21:51,680
there's so much malaria, it could have quite
dramatic impact and it would be cost effective.
937
01:21:51,680 --> 01:21:56,640
I think that was a bit of a surprise to everybody.
We've been aiming for this really high bar,
938
01:21:56,640 --> 01:22:00,560
and then all of a sudden there was this
realization actually a quite a suboptimal
939
01:22:00,560 --> 01:22:05,680
tool could make a big difference. I think
that was quite unfortunate and quite pivotal.
940
01:22:05,680 --> 01:22:12,080
So what did it feel like when the WHO verdict
came in that more studies were needed?
941
01:22:12,080 --> 01:22:17,440
I think it was really disappointing. I think
it's a difficult decision that they had to
942
01:22:17,440 --> 01:22:21,520
make. This is really uncharted territory; a
vaccine with really poor efficacy and this
943
01:22:21,520 --> 01:22:27,680
safety signal. So it's a tough call for
them to make, but I think people at the
944
01:22:27,680 --> 01:22:32,800
time and now still think there could have been
a better way to resolve the safety signal issue.
945
01:22:32,800 --> 01:22:40,400
And had they prepared better for understanding
the public health impact of a vaccine that has
946
01:22:40,400 --> 01:22:44,000
this level of efficacy, maybe that messaging
could have been different when they were
947
01:22:44,000 --> 01:22:48,720
trying to make the recommendations, if they
understood the potential value more fully,
948
01:22:49,840 --> 01:22:57,600
maybe that would've have shifted the approach
away from a pilot implementation program that
949
01:22:57,600 --> 01:23:04,560
took six years to conclude versus doing
a much more rapid safety assessment.
950
01:23:04,560 --> 01:23:10,800
I guess I also, I feel like it's a little
bit surprising just because even the first
951
01:23:10,800 --> 01:23:16,960
field trials in 1997 and 1998 also showed
fairly low efficacy, but they continued
952
01:23:16,960 --> 01:23:21,520
working on it and people probably should
have been prepared by that point that,
953
01:23:21,520 --> 01:23:26,960
hey, this even though this isn't a very highly
effective vaccine, it probably will save a lot
954
01:23:26,960 --> 01:23:38,000
of lives. And so it's surprising that that wasn't
enough to not require another study after that.
955
01:23:38,000 --> 01:23:42,160
Yeah, I think you're right, and what I've
said just now is my recollection of the
956
01:23:42,160 --> 01:23:47,120
events at the time. This is a while ago and
I wasn't deeply involved in the process,
957
01:23:47,120 --> 01:23:52,000
so perhaps there was more preparation than
that I was aware of, but it feels like that
958
01:23:52,000 --> 01:23:55,840
was the missing piece that people didn't
truly, at least the people I was talking to,
959
01:23:55,840 --> 01:24:02,640
didn't truly appreciate the potential impact,
global health impact, of this tool at the time.
960
01:24:02,640 --> 01:24:07,040
And there were other consequences as
well to delaying the rollout. So you'll
961
01:24:07,040 --> 01:24:11,760
see GSK would be hoping that at the end of
their phase three trial, they can scale up
962
01:24:11,760 --> 01:24:15,840
manufacture and start delivering the vaccine.
They probably had a factory that was making it,
963
01:24:15,840 --> 01:24:19,040
but now there was gonna be this huge delay.
What were they gonna do with the facilities
964
01:24:19,040 --> 01:24:22,960
that were producing the vaccine? And then what
was that gonna mean for vaccine supply later
965
01:24:22,960 --> 01:24:30,000
on? All these knock on effects as well that in
hindsight it's easy to think differently about
966
01:24:30,000 --> 01:24:34,080
what we could have done differently. But I'm not
sure it was so easy at the time, to be honest.
967
01:24:34,080 --> 01:24:40,880
It's also just like to state the
obvious, so strange and messed up
968
01:24:40,880 --> 01:24:48,640
that the way that things currently work is
that to get a scalable regulatory opinion,
969
01:24:48,640 --> 01:24:56,640
you end up relying on the EU and the WHO when,
you know, over time we have to get to a world
970
01:24:56,640 --> 01:25:03,840
where kids in Ghana rely on regulators in Ghana,
not these kind of more distant bodies. 'Cause
971
01:25:03,840 --> 01:25:10,240
you could totally imagine, as happened with
the next vaccine, R21, that some nations want
972
01:25:10,240 --> 01:25:16,320
to go ahead with vaccination campaigns,
even if the WHO doesn't agree and they
973
01:25:16,320 --> 01:25:21,840
absolutely should. So that's another part
of this story that's a bit heart wrenching.
974
01:25:21,840 --> 01:25:27,280
I feel like there's also a part of this
that's like what safety standards we're
975
01:25:27,280 --> 01:25:34,000
used to here might be different. Like the
cost benefit just might be very different
976
01:25:34,000 --> 01:25:39,760
and the willingness to take vaccine at
an earlier stage might be different.
977
01:25:39,760 --> 01:25:44,640
But I think there's also another thing that
kind of drew out the process, which was a
978
01:25:44,640 --> 01:25:51,440
lack of funding and a lack of infrastructure
for clinical trials at the time. So especially
979
01:25:51,440 --> 01:25:58,400
in the early 2000s, there were very few trial
sites in Africa where you could actually try to
980
01:25:58,400 --> 01:26:06,240
do research on the malaria vaccine at all. And
it was only in the 2000s when malaria funding
981
01:26:06,240 --> 01:26:13,520
actually grew from various organizations like
the President's Malaria Initiative in the US,
982
01:26:13,520 --> 01:26:21,680
and Unitaid and the PATH's Malaria Vaccine
Initiative that was funded by the Gates
983
01:26:21,680 --> 01:26:30,080
Foundation and the Global Fund. And all of
these appeared only in the mid-, early-2000s.
984
01:26:30,080 --> 01:26:35,600
Until then, it would've been really difficult,
I think, to get enough funding to set up these
985
01:26:35,600 --> 01:26:44,240
trial sites and to actually do the research. To
me, when I think about it seems like mostly a
986
01:26:44,240 --> 01:26:52,240
failure of infrastructure and funding. And
there are also these regulatory concerns,
987
01:26:52,240 --> 01:26:59,680
but if we'd had that sooner, we would've been
able to test many other vaccines as well.
988
01:26:59,680 --> 01:27:02,400
Yeah, I agree with that. I think that's
a really important point. I think,
989
01:27:02,400 --> 01:27:05,360
we take it for granted now that
actually these clinical trial
990
01:27:05,360 --> 01:27:11,280
facilities are so well established, and
the investigators there are so competent,
991
01:27:11,280 --> 01:27:15,520
that they can run their own trials, lead
their own work. That wasn't the case.
992
01:27:15,520 --> 01:27:20,480
I remember the stories of the people
leading the RTS,S work doing the draw
993
01:27:20,480 --> 01:27:24,720
of the sites that existed at the time,
and injecting cash into a lot of these
994
01:27:24,720 --> 01:27:29,360
sites to bring them up to the standards that
would be needed for their product development
995
01:27:30,080 --> 01:27:36,320
needs. So I think a lot of that work
done by GSK has really benefited the rest
996
01:27:36,320 --> 01:27:40,880
of the malaria community and other
development of other vaccines as well.
997
01:27:40,880 --> 01:27:44,640
Okay. So there's infrastructure, which is
key, and also funding, as you mentioned,
998
01:27:44,640 --> 01:27:49,440
Saloni. So let's say that there had been a
big burst of funding back then that was even
999
01:27:49,440 --> 01:27:55,200
bigger than we saw. How would that have
happened? Were there people proposing it?
1000
01:27:55,200 --> 01:27:58,880
There were people proposing it, but they
were proposing a different type of funding.
1001
01:27:59,520 --> 01:28:04,320
Much of the funding that we're talking
about is sort of directed at specific
1002
01:28:04,320 --> 01:28:09,760
groups to do the research, or to set up
the trial sites, and things like that.
1003
01:28:09,760 --> 01:28:17,120
But in 2004, some economists, Michael Kremer
and Rachel Glennerster proposed an Advanced
1004
01:28:17,120 --> 01:28:23,440
Market Commitment, which is a different type
of funding model to try to spur innovation
1005
01:28:23,440 --> 01:28:28,480
and change the commercial incentives for
vaccine development. So the general idea,
1006
01:28:28,480 --> 01:28:34,560
of why did we need philanthropy and like foreign
aid and all of these global health programs,
1007
01:28:34,560 --> 01:28:39,760
is that there isn't otherwise a commercial
incentive to develop vaccines where it's very
1008
01:28:39,760 --> 01:28:46,800
small. The reason for that is that the people who
are most affected by malaria are very poor and you
1009
01:28:46,800 --> 01:28:52,240
can't really sell vaccines at a high price
because they wouldn't be able to afford it.
1010
01:28:53,040 --> 01:28:59,360
So here the idea is, what if we could change those
commercial incentives? And the Advanced Market
1011
01:28:59,360 --> 01:29:06,240
Commitment is a way of doing that. So instead of
directing funding at specific research groups,
1012
01:29:06,240 --> 01:29:13,120
it's actually a pool of funding that is only
available to researchers or to manufacturers
1013
01:29:13,120 --> 01:29:18,640
if they develop a successful vaccine in
trials and they reach certain criteria.
1014
01:29:19,200 --> 01:29:23,200
So Rachel Glennerster and Michael
Kremer proposed this Advanced Market
1015
01:29:23,200 --> 01:29:31,040
Commitment where they said we should have a
commitment for around $3.2 billion in total,
1016
01:29:31,040 --> 01:29:37,360
where you would pay per person who was
vaccinated, for the first 200 million people,
1017
01:29:37,360 --> 01:29:45,760
and you would pay about $13 per person. What this
does is it actually incentivizes companies to
1018
01:29:45,760 --> 01:29:51,920
develop a vaccine and take it to the finish
line. Both invent-, both developing it and
1019
01:29:51,920 --> 01:29:57,120
then also scaling it up because they're only
gonna get that payout per person they immunize.
1020
01:29:57,120 --> 01:30:03,360
So I think that is a really cool model that
spurs commercial development and it's very
1021
01:30:03,360 --> 01:30:09,280
different from the type of funding that was
actually done. But the problem was that that
1022
01:30:09,280 --> 01:30:15,760
idea didn't actually get taken up. And there
were various reasons for that. One was that
1023
01:30:15,760 --> 01:30:22,400
at the time people thought the malaria vaccine
was just too technically difficult. It was too
1024
01:30:22,400 --> 01:30:28,480
far away to be reality. So they didn't want to
use this new funding model that was proposed,
1025
01:30:28,480 --> 01:30:33,680
for something that might not ever happen, and
they thought that you, we have to have a lot
1026
01:30:33,680 --> 01:30:40,960
more basic R&D before we'd have a product that
could reach that standard. That also just made it
1027
01:30:40,960 --> 01:30:46,960
more politically risky. People were like, well,
we want something that will definitely or has a
1028
01:30:46,960 --> 01:30:52,880
much higher chance of success. We want a proof
of concept that this funding model could work.
1029
01:30:52,880 --> 01:30:59,280
And the other problem is that it's hard, in
a commitment like that, which is essentially
1030
01:30:59,280 --> 01:31:04,720
this legal document that funders, in this
case they would be countries - governments,
1031
01:31:04,720 --> 01:31:10,080
or philanthropists agreeing to pay out a
vaccine that meets these standards. It's
1032
01:31:10,080 --> 01:31:16,880
hard to decide what those standards are and what
kinds of products would fit those criteria if you
1033
01:31:16,880 --> 01:31:21,840
don't have a malaria vaccine yet, and you don't
have like things that are late in the pipeline.
1034
01:31:21,840 --> 01:31:29,280
So instead of doing an Advanced Market Commitment
for malaria, there was a different Advanced Market
1035
01:31:29,280 --> 01:31:37,680
Commitment that was actually implemented, and that
was for the pneumococcal vaccine. And so in 2009,
1036
01:31:37,680 --> 01:31:43,760
various countries and the Gates Foundation came
together to fund an Advanced Market Commitment to
1037
01:31:43,760 --> 01:31:49,440
develop a new pneumococcal vaccine that would
target the strains that were common in Africa
1038
01:31:49,440 --> 01:31:55,920
and South Asia. Those strains were not included in
the previous pneumococcal vaccines, but there was
1039
01:31:55,920 --> 01:32:00,720
already a proof of concept that we have this, we
have these other pneumococcal vaccines, it should
1040
01:32:00,720 --> 01:32:08,640
be fairly easy to turn to make new ones against
these strains. And it worked. So there were three
1041
01:32:08,640 --> 01:32:15,120
companies, I think, that quickly developed these
pneumococcal vaccines, took them through phase
1042
01:32:15,120 --> 01:32:21,840
three trials and then manufactured them in
bulk to get that payout from the commitment.
1043
01:32:22,720 --> 01:32:30,320
I personally think it feels like
a very big missed opportunity to
1044
01:32:30,320 --> 01:32:35,760
use it for malaria as well. But many
people disagreed with that at the time.
1045
01:32:35,760 --> 01:32:39,200
Okay. Katharine, you were around. Do
you think it would've worked back then?
1046
01:32:39,200 --> 01:32:42,960
I'm not sure. I think the
limitations were scientific,
1047
01:32:42,960 --> 01:32:44,880
biological, we had the
problems with the adjuvants,
1048
01:32:44,880 --> 01:32:50,880
we had lack of trial infrastructure. I'm not
sure it would've made things go much faster.
1049
01:32:50,880 --> 01:32:56,960
Well, it's hard to say as well, because this
was proposed in 2004. And so at that point,
1050
01:32:56,960 --> 01:33:03,920
the RTS,S vaccine already existed and it already
had like an efficacy of 30 something percent. And
1051
01:33:03,920 --> 01:33:09,040
so if you were at the time, and you were trying
to put this commitment together and you said,
1052
01:33:09,040 --> 01:33:14,720
we'll fund a vaccine that reaches these
standards, probably you would, the standards
1053
01:33:14,720 --> 01:33:20,160
that you would ask a vaccine to be developed
for would be higher than the 30% I think.
1054
01:33:20,160 --> 01:33:25,920
So I think in that sense it would've been
hard. What's interesting though is that
1055
01:33:25,920 --> 01:33:31,440
there was another paper in 2005 where
they tried to model this explicitly,
1056
01:33:31,440 --> 01:33:37,120
so trying to model the cost-effectiveness under
different estimates of the efficacy. Like if
1057
01:33:37,120 --> 01:33:45,040
it was 30%, how would it be cost effective? If
it was 60%, et cetera? And this was a paper by
1058
01:33:45,040 --> 01:33:50,240
also Rachel Glennerster, Michael Kremer,
many other economists, Heidi Williams,
1059
01:33:50,240 --> 01:33:55,680
and they found basically that it was, it
would still be cost effective to fund an
1060
01:33:55,680 --> 01:34:01,520
Advanced Market Commitment for a malaria
vaccine, even if the efficacy was only 30%.
1061
01:34:01,520 --> 01:34:10,000
So I think to some degree there had been a bunch
of thinking on this, but at the same time, I don't
1062
01:34:10,000 --> 01:34:15,760
think we know what the counterfactual is because
I don't think that other, there are enough other
1063
01:34:15,760 --> 01:34:23,840
commercial companies that are developing malaria
vaccines now that we can compare this to. Like
1064
01:34:24,880 --> 01:34:30,800
the thing that is effective about the Advanced
Market Commitment is that it gets people to enter
1065
01:34:30,800 --> 01:34:37,120
the market that wouldn't otherwise. And so it's
hard to know how that could have gone, I think.
1066
01:34:37,120 --> 01:34:43,520
I think that's the bit that I agree with
that there weren't other people that
1067
01:34:43,520 --> 01:34:48,400
were that far advanced in their vaccine. The
only thing that has worked to date is a CSP
1068
01:34:48,400 --> 01:34:54,320
based vaccine. There were people working on other
types of vaccines at the time. But it's not sure,
1069
01:34:54,320 --> 01:35:00,640
because it's not clear any of those would've made
it either, or looked promising enough to advance.
1070
01:35:00,640 --> 01:35:06,080
So that's a pull funding mechanism incentive
to get to the finish line. Katharine,
1071
01:35:06,080 --> 01:35:12,640
did it feel like more grant money, and more
universities, and more companies wherever,
1072
01:35:12,640 --> 01:35:16,480
would have made the difference if there
was a hundred million more every year
1073
01:35:16,480 --> 01:35:20,480
going into malaria vaccines? Or
did it feel like the science and
1074
01:35:20,480 --> 01:35:26,720
the infrastructure - you can't rush that, and
you actually just have to do it step by step?
1075
01:35:26,720 --> 01:35:29,840
That's a very good question and,
actually I, maybe I'm gonna change
1076
01:35:29,840 --> 01:35:34,160
my opinion slightly and that there were
other, with more funding available,
1077
01:35:34,160 --> 01:35:39,280
there were other people doing great science at
the time. So Simon Draper at the University of
1078
01:35:39,280 --> 01:35:45,040
Oxford has developed a blood stage vaccine with
RH5, and that work was happening at the same
1079
01:35:45,040 --> 01:35:52,000
time on the lab bench next to me, when I was
doing R21. But that was seriously underfunded,
1080
01:35:52,000 --> 01:35:55,600
so there was - people had to prioritize what
they were gonna support with their funding,
1081
01:35:55,600 --> 01:36:03,040
there was limited funding. So the focus went on
to CSP based vaccines and that's what the Gates
1082
01:36:03,040 --> 01:36:10,640
Foundation funded the RTS,S vaccine through MVI
and the Gates Foundation didn't fund blood stage.
1083
01:36:10,640 --> 01:36:14,640
There was only one funder at the time that was
supporting that work, or one main funder, and that
1084
01:36:14,640 --> 01:36:18,480
was USAID (United States Agency for International
Development). Had there been more money, that work
1085
01:36:18,480 --> 01:36:24,320
could have been accelerated. And you know, that's
shown now in a phase two trial that it gives good
1086
01:36:24,320 --> 01:36:33,760
levels of efficacy, not as high as R21 and RTS,S,
but there's potential to combine that with R21.
1087
01:36:33,760 --> 01:36:37,680
So that work could have been accelerated a lot
quicker, had there been more funding around.
1088
01:36:37,680 --> 01:36:41,200
So just playing that out. So that,
that result you just referenced,
1089
01:36:41,200 --> 01:36:46,160
that was from about a year ago, was it? That
was pretty recent. Right? Yeah. And so if that
1090
01:36:46,160 --> 01:36:51,440
funding had happened a decade earlier, could
that result have come about a decade earlier,
1091
01:36:51,440 --> 01:36:55,200
do you think? Or is - that's
just a funding question really.
1092
01:36:55,200 --> 01:37:01,745
Yeah, I think the product was the one
they were working on in the beginning.
1093
01:37:01,745 --> 01:37:01,760
No!!
Depressing.
1094
01:37:01,760 --> 01:37:05,120
Wow. That is incredibly depressing.
1095
01:37:05,120 --> 01:37:12,080
I know, but I think credit has to go to Simon
Draper and the funders that supported him and
1096
01:37:12,080 --> 01:37:17,200
Lorraine Soisson at USAID, they kept that
work going with quite limited budgets,
1097
01:37:17,200 --> 01:37:20,400
and they've made it to the finish
line, well, not to the finish line,
1098
01:37:20,400 --> 01:37:24,390
but to the clinical trials
now, and the efficacy trials.
1099
01:37:24,390 --> 01:37:24,400
Wow, geez.
1100
01:37:24,400 --> 01:37:30,160
Thank you Simon. Thank you Lorraine, for
believing against consensus and keeping it going.
1101
01:37:30,160 --> 01:37:35,200
I have a question related to this because
both these are different stages of the
1102
01:37:35,200 --> 01:37:41,680
vaccine and so I'm wondering if you had a
vaccine that combines the vaccines against
1103
01:37:41,680 --> 01:37:45,920
both of these different stages, would you
expect that to have a higher efficacy,
1104
01:37:45,920 --> 01:37:50,000
and have people tried to do things like that?
1105
01:37:50,000 --> 01:37:55,200
Yeah, I think that was the original approach
from Adrian, when I was making R21. He also
1106
01:37:55,200 --> 01:38:00,268
had a liver stage vaccine. The other vaccine he
had developed was the ME-TRAP vaccine (Multiple
1107
01:38:00,268 --> 01:38:04,080
Epitope–Thrombospondin-Related Adhesion Protein),
and that targeted the infected hepatocytes.
1108
01:38:04,080 --> 01:38:08,160
His theory was that if you could reduce the
number of sporozoites that get to the liver,
1109
01:38:08,160 --> 01:38:13,680
then the liver stage vaccine would have an easier
time finding and clearing out those liver cells.
1110
01:38:13,680 --> 01:38:21,280
And that was valua - that was tested and it didn't
work, so that was a great theory that didn't work.
1111
01:38:21,280 --> 01:38:26,960
Now people are looking at combining the CSP based
vaccines with the blood stage vaccines that Simon
1112
01:38:26,960 --> 01:38:30,320
Draper's developed and others. There are lots of
other people working on blood stage vaccines now
1113
01:38:30,320 --> 01:38:36,880
as well. But the preclinical models are really
difficult to evaluate all stages of the parasites
1114
01:38:36,880 --> 01:38:42,240
in the same model and the combination of those
vaccines. So we really have to get into humans,
1115
01:38:42,240 --> 01:38:46,960
and that's the work that Simon and Angela
and his team are working on at the moment.
1116
01:38:46,960 --> 01:38:51,920
Wow. And so that was also - could that
have also been sped up by 10 years?
1117
01:38:51,920 --> 01:38:56,320
Yeah, that vaccine that they're now putting
into clinical trials with R21 was being
1118
01:38:56,320 --> 01:39:01,440
developed at the same time as I was developing
R21. So I know that could have gone quicker.
1119
01:39:01,440 --> 01:39:03,200
This is crazy.
1120
01:39:03,200 --> 01:39:11,920
It wasn't exactly hard to spot, it was right next
to you on the lab next to you. I'm gonna cry.
1121
01:39:11,920 --> 01:39:12,720
Geez.
1122
01:39:12,720 --> 01:39:19,040
I mean, so as someone who works in philanthropic
funding, I think the main lesson here is just
1123
01:39:19,920 --> 01:39:25,920
that funding in global health R&D is
so tight that you have to make these
1124
01:39:25,920 --> 01:39:34,800
prioritization decisions that are vicious and
impossible. So we just - I mean, a more sane
1125
01:39:34,800 --> 01:39:42,160
society would have more long-term government and
philanthropic funding that was less correlated,
1126
01:39:42,160 --> 01:39:47,200
more decision makers, more money total,
so that you could get more shots on goal.
1127
01:39:47,200 --> 01:39:54,320
So I think, for anyone listening who
is wondering what the solution is,
1128
01:39:54,320 --> 01:39:59,440
I think that's the most obvious general solution
staring us in the face, and so I don't wanna hide
1129
01:39:59,440 --> 01:40:03,360
it. There's obviously all these specifics
we can get into that are more technical,
1130
01:40:03,360 --> 01:40:11,200
but that one is just - is obvious. So
we just have to say it out loud. Sorry!
1131
01:40:11,200 --> 01:40:12,800
Geez.
1132
01:40:12,800 --> 01:40:16,640
No, I agree with that. I don't disagree with
the decisions that were made about what you
1133
01:40:16,640 --> 01:40:20,000
had to prioritize at the time. I think
they were tough decisions that people had
1134
01:40:20,000 --> 01:40:24,720
to make. That had there been more money,
we could have moved things a lot faster.
1135
01:40:25,280 --> 01:40:31,760
I feel like what's even more depressing
about this is that... Despite all of that,
1136
01:40:31,760 --> 01:40:37,280
malaria is still one of the more well-funded
diseases in global health world, and there
1137
01:40:37,280 --> 01:40:43,440
are various others that are large burdens
and get tiny fractions of the funding.
1138
01:40:43,440 --> 01:40:48,720
I am wondering if we could just talk about the
two vaccines already approved next to each other,
1139
01:40:48,720 --> 01:40:54,240
and then what's coming next after these two? What
needs to be done next in the invention pipeline?
1140
01:40:54,240 --> 01:41:03,840
So RTS,S versus R21. I will tee this off by saying
I don't know that there's - there are different
1141
01:41:03,840 --> 01:41:10,960
comparisons you could make, but one fact just to
state upfront is that neither has faced a rollout
1142
01:41:10,960 --> 01:41:16,080
where tens of millions of children have received
the vaccine, so perhaps the biggest problem is
1143
01:41:16,080 --> 01:41:23,680
simply that there is not enough reach of either
of them, let alone comparing between the two.
1144
01:41:23,680 --> 01:41:27,760
That said, what do we know
about the data that has come in,
1145
01:41:27,760 --> 01:41:31,760
about how they look? So there's
more data coming in every year,
1146
01:41:31,760 --> 01:41:39,440
but what do we know so far about efficacy,
about safety, and other factors? Katharine?
1147
01:41:39,440 --> 01:41:43,600
The headline efficacy figures from the phase
three trials look quite different for the two
1148
01:41:43,600 --> 01:41:51,040
vaccines. So RTS,S, we mentioned it was something
like 36% an efficacy overall. And actually for
1149
01:41:51,040 --> 01:41:57,360
the population that was used for the phase
three trials for R21, that was most similar,
1150
01:41:57,360 --> 01:42:05,040
the efficacy I think was 57% overall. And then for
R21, the phase three result was something around
1151
01:42:05,040 --> 01:42:13,120
75%. I can't remember the same, the exact numbers,
so this looks like R21 may be a lot better.
1152
01:42:13,120 --> 01:42:17,040
But there's some nuance and detail
about how these trials were conducted,
1153
01:42:17,040 --> 01:42:21,520
and where they were conducted, and when they were
conducted, that means we can't - we probably can't
1154
01:42:21,520 --> 01:42:27,440
directly compare these trial results. So I don't
think you can claim that R21 definitely has a
1155
01:42:27,440 --> 01:42:32,800
higher level of efficacy. There were different
things happening at the time; different other
1156
01:42:32,800 --> 01:42:38,400
malaria interventions that were being used,
like bed nets, or seasonal chemo-prevention
1157
01:42:38,400 --> 01:42:43,600
drugs that were given to children every year,
so those results aren't directly comparable.
1158
01:42:43,600 --> 01:42:49,120
So I think we have to try not to make that
comparison unless we run a head-to-head trial.
1159
01:42:49,120 --> 01:42:53,760
What I think is interesting about the R21 data
that's starting to emerge is that it does - it
1160
01:42:53,760 --> 01:43:02,800
may be more durable than RTS,S. So the decline of
protection seems to be slightly slower. So it may,
1161
01:43:02,800 --> 01:43:07,280
even if the efficacy isn't much different,
that peak protection they gets the,
1162
01:43:07,280 --> 01:43:10,880
it may last a little bit longer, so
that could make quite a big difference.
1163
01:43:10,880 --> 01:43:14,880
I see. So, but in both cases, your first shot,
1164
01:43:14,880 --> 01:43:19,280
you'll probably get it at five months old. Is
that about right? And then you might get another,
1165
01:43:19,280 --> 01:43:24,000
the ideal is you get one at five, one
at six, one at seven months. And you're
1166
01:43:24,000 --> 01:43:31,680
saying that the immune response from R21 is
lasting for longer after those first shots?
1167
01:43:31,680 --> 01:43:36,480
That's right. That's actually a fourth
dose that's given around 18 months.
1168
01:43:36,480 --> 01:43:43,760
I think my takeaway from the difference
between the two is mostly the manufacturing
1169
01:43:43,760 --> 01:43:49,920
and the cost. Is that also how you see
it? And are there any other differences?
1170
01:43:49,920 --> 01:43:55,520
Why is there such a huge difference
in the cost of both of these? And is
1171
01:43:55,520 --> 01:43:59,120
that because of the dosing that
we talked about at the start?
1172
01:43:59,120 --> 01:44:05,920
I guess, the other big difference is of
the scalability of the vaccines. R21,
1173
01:44:06,880 --> 01:44:12,240
it seems to be easier and cheaper to produce
and that may be in part due to the lower dose
1174
01:44:12,240 --> 01:44:18,320
and maybe also new technologies that have been
used to produce the vaccine itself - so newer
1175
01:44:18,320 --> 01:44:25,520
yeast expression systems and things like that. And
also, the adjuvant that's added to the vaccine.
1176
01:44:25,520 --> 01:44:30,800
As we mentioned earlier, that the adjuvant
was really important for the RTS,S vaccine.
1177
01:44:30,800 --> 01:44:37,680
We found the same with R21, only when we used
a certain adjuvant did we see protection. And
1178
01:44:37,680 --> 01:44:42,080
that the adjuvant that's been chosen for R21
was Matrix-M and that doesn't have the same
1179
01:44:42,080 --> 01:44:50,000
supply limitations as AS01, and it's slightly
cheaper as well. So that makes it more scalable.
1180
01:44:50,000 --> 01:44:54,960
Yeah, I mean it's funny, it's not the property
you'd think about first – scalability,
1181
01:44:54,960 --> 01:45:02,160
and how that might have implications for cost
and price. But last price that I saw for RTS,S
1182
01:45:02,160 --> 01:45:10,960
was about €9 a dose and there are four doses. And
then the last price I saw for R21 was the original
1183
01:45:10,960 --> 01:45:17,840
price was 3.90 and it maybe has come down to
$3? So we're, we're talking about a 3X, say,
1184
01:45:17,840 --> 01:45:24,960
difference, which may not sound like much, but
is decisive in a lot of these cost-effectiveness
1185
01:45:24,960 --> 01:45:30,000
calculations because global health funding,
there's just not so much of it going around.
1186
01:45:30,000 --> 01:45:36,160
So when you think of cost-effectiveness, it's
not just how effective are these vaccines,
1187
01:45:36,160 --> 01:45:40,240
it's how much it cost to actually deliver
them to the kids who need them. So anything
1188
01:45:40,240 --> 01:45:44,480
you can do to bring the numbers down
is, it could change the equation.
1189
01:45:44,480 --> 01:45:49,920
Yeah. And just going back to the delivery schedule
you mentioned earlier Jacob, which is giving doses
1190
01:45:49,920 --> 01:45:54,720
of the vaccine at five, six, and seven months.
And then there's this booster dose or final dose
1191
01:45:54,720 --> 01:45:58,720
that's given around a year later, and none of
these time points are actually aligned with
1192
01:45:58,720 --> 01:46:04,320
the schedule for other infant vaccines. So what
this means in reality is that children and their
1193
01:46:04,320 --> 01:46:10,960
parents and caregivers have to travel for each
of these visits at another time. And what we're
1194
01:46:10,960 --> 01:46:15,920
finding is that people are not showing up for all
of their doses of vaccine, and so if they're not
1195
01:46:15,920 --> 01:46:20,640
getting the full course, it's gonna reduce
the effectiveness of both of these vaccines.
1196
01:46:20,640 --> 01:46:26,320
Right. If you have to travel three months
in a row, but you are busy taking care of
1197
01:46:26,320 --> 01:46:29,920
your other kids or you're at work, or, I
mean, it's, you can see how you might miss
1198
01:46:29,920 --> 01:46:34,160
a dose. And then if that happens, then
whatever we saw in the clinical trial
1199
01:46:34,160 --> 01:46:40,640
may not reflect the reality of what kids are
getting protected, so more work to do there.
1200
01:46:40,640 --> 01:46:46,720
Okay. So those are two
vaccines and they're imperfect,
1201
01:46:46,720 --> 01:46:53,120
but they are helpful for kids. Do you
think they're good enough, Katharine?
1202
01:46:53,120 --> 01:46:58,480
If we did this again today,
could we make better vaccines?
1203
01:46:58,480 --> 01:47:03,600
Uh, yeah, I think well, oh gosh.
Wow. That's a tough one. I think...
1204
01:47:03,600 --> 01:47:09,600
I mean, scientifically, not in terms of the
funding or trials or anything like that.
1205
01:47:09,600 --> 01:47:16,240
Yeah, I think we have better techniques
and technologies for developing
1206
01:47:16,240 --> 01:47:22,160
vaccines. Structured-guided design, reverse
vaccinology, computational protein design,
1207
01:47:22,160 --> 01:47:27,040
things that you've talked about in your
previous podcast episodes, where we really
1208
01:47:27,040 --> 01:47:32,960
try and understand more specifically what type
of immune response you want to generate. So you
1209
01:47:32,960 --> 01:47:36,880
can take the whole protein that you think is
important, and show that to the immune system,
1210
01:47:36,880 --> 01:47:41,440
but it might generate a mixture of
helpful responses and unhelpful responses.
1211
01:47:41,440 --> 01:47:47,280
So using these more sophisticated techniques,
we can try and understand which parts are really
1212
01:47:47,280 --> 01:47:52,240
helpful, and design the proteins or the
antigens to really elicit those responses
1213
01:47:52,240 --> 01:47:57,680
more carefully and more specifically. So using
those techniques, people are already doing this.
1214
01:47:57,680 --> 01:48:02,080
They're working on trying to make better
CSP vaccines, better blood stage vaccines,
1215
01:48:02,080 --> 01:48:05,760
and also vaccines that target the
transmission blocking stage as well.
1216
01:48:05,760 --> 01:48:08,560
But why were you hesitant before?
1217
01:48:08,560 --> 01:48:13,680
It's not clear that any of those will actually
be any better. So I think there was a really
1218
01:48:13,680 --> 01:48:18,400
interesting paper published by the Protein Design
Institute by Neil King, someone that we support
1219
01:48:18,400 --> 01:48:24,960
and think is an incredible institute for using
computational design to really improve vaccine
1220
01:48:24,960 --> 01:48:31,520
antigens. And they tried to make better versions
of R21, and I can't remember what the paper showed
1221
01:48:31,520 --> 01:48:37,360
exactly now, but there were many candidates
they assessed and they used this incredible
1222
01:48:37,360 --> 01:48:41,600
methodology to try and improve the vaccines, but
none of them looked substantially better than R21.
1223
01:48:42,880 --> 01:48:48,320
What do you think of the whole sporozoite
vaccines where scientists were just
1224
01:48:48,320 --> 01:48:51,600
irradiating the whole parasite at the
early stage and injecting that as a
1225
01:48:51,600 --> 01:48:54,320
whole? I think they were doing that
in the '70s, and that seems like in
1226
01:48:54,320 --> 01:48:58,320
that research it was pretty effective and
some people are continuing to work on it.
1227
01:48:58,320 --> 01:49:02,640
Yeah, absolutely. I think those are some
of the first data that really stimulated
1228
01:49:02,640 --> 01:49:06,560
the vaccine development community. They
showed really early on, decades ago,
1229
01:49:06,560 --> 01:49:12,000
that you could protect people by using these
irradiated sporozoites, and that work continued.
1230
01:49:12,000 --> 01:49:18,720
So a company called Sanaria, with Steve Hoffman
and others, developed the PfSPZ vaccine,
1231
01:49:18,720 --> 01:49:23,840
and this worked really well with
three doses in people in the US,
1232
01:49:23,840 --> 01:49:27,760
so people who had no experience with
malaria infections before. But when they
1233
01:49:27,760 --> 01:49:32,480
ultimately got this into children in Africa
who had had malaria infections in the past,
1234
01:49:32,480 --> 01:49:37,600
the vaccines didn't work very well, so that
hasn't moved forward for that population.
1235
01:49:37,600 --> 01:49:40,480
There's actually been some really
interesting work more recently that
1236
01:49:40,480 --> 01:49:44,880
they've used genetically attenuated parasites.
So instead of irradiating the parasites and
1237
01:49:44,880 --> 01:49:50,400
then using them, they've made them so that
they can't survive beyond the liver stage,
1238
01:49:50,400 --> 01:49:55,280
but importantly, if these parasites
live to the end of the liver stage,
1239
01:49:55,280 --> 01:49:59,920
then they're really protective. And there
was a recent study where they showed that a
1240
01:49:59,920 --> 01:50:05,440
single dose of this vaccine provided really high
levels of protection in their challenge trial.
1241
01:50:05,440 --> 01:50:08,880
But again, this was in people that
haven't been exposed to malaria before,
1242
01:50:08,880 --> 01:50:11,360
so while this looks really exciting at the moment,
1243
01:50:11,360 --> 01:50:15,280
it still needs to be tested in the field,
in people who have been exposed to malaria,
1244
01:50:15,280 --> 01:50:19,360
and then ultimately in children as well. But
it's really exciting. It's pretty game changing
1245
01:50:19,360 --> 01:50:25,680
if you can get a single dose vaccine to protect
against malaria; we've never seen that before.
1246
01:50:25,680 --> 01:50:30,320
But the challenge with these parasites is that
they need to be stored in liquid nitrogen,
1247
01:50:30,320 --> 01:50:35,680
so you can't just kill them like we have done
in the past with other whole pathogen vaccines.
1248
01:50:35,680 --> 01:50:39,840
They need to be viable, they need to be able to
survive in the liver, and that's gonna be quite
1249
01:50:39,840 --> 01:50:44,080
challenging for delivery in Africa, because there
aren't liquid nitrogen facilities everywhere.
1250
01:50:44,080 --> 01:50:45,680
Why does it have to be so cold?
1251
01:50:46,240 --> 01:50:48,874
That's the way of putting them in stasis.
1252
01:50:48,874 --> 01:50:50,080
Is it just preserving them?
1253
01:50:50,080 --> 01:50:54,320
Preserving them, yeah. So that they
can be woken up. They've either got
1254
01:50:54,320 --> 01:50:59,920
to be kept alive until you inject them,
or you can try and cryo-preserve them in
1255
01:50:59,920 --> 01:51:03,600
a way that they could be thawed,
and then they'd still be viable.
1256
01:51:03,600 --> 01:51:07,920
What if someone found a different way
to preserve them for a long time? Are
1257
01:51:07,920 --> 01:51:13,760
there other options? Can you
like freeze frame a vaccine?
1258
01:51:13,760 --> 01:51:19,360
No. The - no?
1259
01:51:19,360 --> 01:51:25,600
I have no idea. I feel, well, I've
been watching a lot of Pokémon and
1260
01:51:25,600 --> 01:51:32,560
Team Rocket has all of these crazy
tools and equipment to do things.
1261
01:51:32,560 --> 01:51:34,080
We can learn from them.
1262
01:51:34,080 --> 01:51:40,160
I feel like they would have a laser beam
that could just freeze someone in place.
1263
01:51:40,160 --> 01:51:41,440
That would be cool, yeah.
1264
01:51:41,440 --> 01:51:48,880
Let's take a note. Let, let's look into that,
I think that could be pretty interesting.
1265
01:51:48,880 --> 01:51:53,200
I know a funder that's just started there.
1266
01:51:53,200 --> 01:51:56,960
Yeah. Yeah. Let me just, actually I've
already got too much in my laser beam column,
1267
01:51:56,960 --> 01:51:59,920
someone else is gonna have fund that one. But...
1268
01:51:59,920 --> 01:52:03,360
Also this laser beam thing
that could freeze - could be
1269
01:52:03,360 --> 01:52:06,560
used much more widely than just malaria research.
1270
01:52:06,560 --> 01:52:11,280
You could zap people miles away. It's interesting
1271
01:52:11,280 --> 01:52:15,920
I don't hear people talking about this
more given how important it could be.
1272
01:52:15,920 --> 01:52:16,400
Yeah!
1273
01:52:16,400 --> 01:52:22,880
Now on our current technologies, boring, so
it sounds like - my sort of takeaways from
1274
01:52:22,880 --> 01:52:27,760
this section are that when people talk about
vaccines, the thing you always hear about is
1275
01:52:27,760 --> 01:52:34,160
efficacy. COVID vaccine is 90% efficacious, blah,
blah, blah, blah, blah. But that is one number.
1276
01:52:34,160 --> 01:52:40,560
Firstly, that number does not bake
in to the public narrative, duration.
1277
01:52:40,560 --> 01:52:46,400
It does not matter if something is 90%
efficacious and lasts for three months,
1278
01:52:46,400 --> 01:52:52,960
if it then decays. Secondly, it doesn't bake in
cost. What's the manufacturability of this? How
1279
01:52:52,960 --> 01:52:58,720
widespread is it gonna be in a global health
context? But then in addition, it doesn't bake
1280
01:52:58,720 --> 01:53:07,520
in how many doses do you need? And, in a context
where people might not be - they're juggling a
1281
01:53:07,520 --> 01:53:12,640
lot, may not come back for a second, third, or
fourth dose; getting down from four to three,
1282
01:53:12,640 --> 01:53:16,960
three to two or two to one is just an
incredibly big deal, not for scientists,
1283
01:53:16,960 --> 01:53:20,400
but for people in the real world who're
actually gonna be taking these vaccines.
1284
01:53:20,400 --> 01:53:23,360
So Katharine, is that a fair summary?
1285
01:53:23,360 --> 01:53:25,120
Yeah, absolutely. Spot on.
1286
01:53:25,120 --> 01:53:31,520
It reminds me of, you know the HPV vaccine,
where it was originally a three dose vaccine,
1287
01:53:31,520 --> 01:53:37,200
and then it turned out that actually one
dose was really effective. But it took a
1288
01:53:37,200 --> 01:53:41,840
really long time for them to change the
recommendation on how many doses people
1289
01:53:41,840 --> 01:53:46,960
needed. And now that they have that new
recommendation that you only need one dose,
1290
01:53:46,960 --> 01:53:49,760
you can actually scale it up
much more widely than before.
1291
01:53:50,320 --> 01:53:55,520
So, Katharine, if you had to make a
guess, I'm gonna put you on the spot:
1292
01:53:55,520 --> 01:54:07,440
in 10 years will we have an approved vaccine
in use, which is, say, two doses for kids?
1293
01:54:07,440 --> 01:54:11,920
10 years, I think, two doses is too
high a bar. I think we can get to three.
1294
01:54:11,920 --> 01:54:12,960
Mm.
1295
01:54:12,960 --> 01:54:18,800
I think we can get to a more durable and a
more protective vaccine with three doses.
1296
01:54:20,160 --> 01:54:24,240
What's the - what are the
barriers to making it happen?
1297
01:54:24,240 --> 01:54:29,040
I don't know. Maybe I wanna change
my answer there. I think 10 years,
1298
01:54:29,040 --> 01:54:33,280
I would put it 60% chance we can get to two doses.
1299
01:54:33,280 --> 01:54:37,989
Okay. But it's all to play for, you're
saying it really could go either way.
1300
01:54:37,989 --> 01:54:41,440
Yeah, it's not a done deal. I think
60% chance we can get to two doses,
1301
01:54:41,440 --> 01:54:44,800
like 90% chance we're gonna have a better vaccine.
1302
01:54:44,800 --> 01:54:45,280
Okay.
1303
01:54:45,280 --> 01:54:51,040
Three doses, 90%. That's too high, 80%.
1304
01:54:51,040 --> 01:54:55,600
Okay. So you're saying we've
got to plug away and get to
1305
01:54:55,600 --> 01:54:59,280
a better vaccine than even the one you invented.
1306
01:54:59,280 --> 01:55:07,520
Definitely! R21 is suboptimal. It can have
impact like we've discussed, but it's not a
1307
01:55:07,520 --> 01:55:13,400
game changing vaccine. The delivery challenges,
the durability - that all needs to be solved.
1308
01:55:13,400 --> 01:55:14,480
Hmm.
1309
01:55:14,480 --> 01:55:19,840
Okay. So challenge number one then. So you're
saying there's a good chance if we really push
1310
01:55:19,840 --> 01:55:24,640
for it, we can get to a better vaccine. Maybe
it's three doses, maybe it's longer duration,
1311
01:55:24,640 --> 01:55:31,680
and then - but we have to also be aiming at the
same time for even further improvement for kids,
1312
01:55:31,680 --> 01:55:35,280
and that's hopefully getting to perhaps two doses,
1313
01:55:35,280 --> 01:55:39,600
perhaps, you know, transmission
blocking, that kind of thing.
1314
01:55:39,600 --> 01:55:40,960
Yeah, absolutely.
1315
01:55:40,960 --> 01:55:46,400
So it's all to play for. Okay. Saloni, how
are you feeling at the end of this section?
1316
01:55:46,400 --> 01:55:48,800
This makes me sad.
1317
01:55:50,000 --> 01:55:56,720
I feel like it's so sad that one, our technology
has improved so much, but it doesn't seem to have
1318
01:55:56,720 --> 01:56:02,000
made that much of a difference in terms of
the efficacy – except for this one vaccine,
1319
01:56:02,000 --> 01:56:09,280
which is really hard to scale up because you
need to cryo-preserve the sporozoite stage,
1320
01:56:09,280 --> 01:56:17,760
which means that it sort of rules it out being
used widely. And the third thing, is that there
1321
01:56:17,760 --> 01:56:23,920
were like various vaccines that are in late stages
of trials right now that could have been in late
1322
01:56:23,920 --> 01:56:31,520
stages 10 years ago. It's just the combination of
all of that is just incredibly depressing to me.
1323
01:56:31,520 --> 01:56:35,680
Yeah. Well, can I try and cheer you up?
1324
01:56:35,680 --> 01:56:36,720
Yes.
1325
01:56:38,400 --> 01:56:45,280
Just to reorient to how many lives a vaccine
can save. That is even imperfect. You know,
1326
01:56:45,280 --> 01:56:54,080
if R21 or RTS,S - I mean R21 seems more likely
now - could scale up to more children who need it,
1327
01:56:54,080 --> 01:56:59,280
tens of thousands of children's lives would be
saved already. And then Katharine is telling
1328
01:56:59,280 --> 01:57:04,400
us that within 10 years, we have a good shot
at an improved vaccine that's even better,
1329
01:57:04,400 --> 01:57:07,040
so that is gonna matter to a lot of children.
1330
01:57:07,040 --> 01:57:13,840
And science, the reality of this problem
is the hardness of it is set by nature,
1331
01:57:13,840 --> 01:57:21,120
and nature is a vicious, vicious, test setter
sometimes. The fact we've got this far, I mean,
1332
01:57:21,120 --> 01:57:26,640
that is pretty impressive and we have a ways to
go, but there's a line of sight to improvement,
1333
01:57:26,640 --> 01:57:32,480
even if not to the absolute a hundred
percent blocking one dose thing.
1334
01:57:32,480 --> 01:57:37,920
I mean, I'm happy for the children
who are getting these vaccines,
1335
01:57:37,920 --> 01:57:43,440
but it's just that counterfactual. It's
just very hard to get out of your head.
1336
01:57:43,440 --> 01:57:50,720
Yeah. Yeah. So, Katharine, as you look
to the next 10 years, how do you feel?
1337
01:57:50,720 --> 01:57:56,560
I'm optimistic. I think we can do better. I think
we've got great people doing incredible work,
1338
01:57:56,560 --> 01:58:02,960
great new tools and more people thinking
about the problem end to end. So more
1339
01:58:02,960 --> 01:58:07,840
people thinking more about more than just
efficacy, with all the other criteria you
1340
01:58:07,840 --> 01:58:11,760
raised that we should be considering.
More developers are now aware of all
1341
01:58:11,760 --> 01:58:20,080
of those things to consider in the development
pathway, and so I think there's a lot of hope.
1342
01:58:20,080 --> 01:58:26,080
There's also the current rollout,
right? That we could scale up.
1343
01:58:26,080 --> 01:58:29,360
Yeah, I think that's a tough one. I think
it's a really difficult funding environment,
1344
01:58:29,360 --> 01:58:33,920
so we don't have enough donor support to provide
1345
01:58:33,920 --> 01:58:37,680
R21 and RTS,S or the countries that
would like it, that would need it,
1346
01:58:37,680 --> 01:58:45,760
and are requesting from Gavi. So if we had more
support coming from the different donor countries.
1347
01:58:45,760 --> 01:58:49,520
The UK's cutting back, US cutting
back, Japan's cutting back.
1348
01:58:49,520 --> 01:58:56,720
Germany as well. What I read from a report,
talking about the situation at the time,
1349
01:58:56,720 --> 01:59:02,080
two years ago, was back then, both of
the vaccines had been pre-qualified
1350
01:59:02,080 --> 01:59:10,000
from by the World Health Organization
and they were being rolled out and they
1351
01:59:10,000 --> 01:59:17,760
estimated that it would take another
12 years after that for all children
1352
01:59:17,760 --> 01:59:23,200
under three in the countries with high
malaria prevalence to be vaccinated.
1353
01:59:23,200 --> 01:59:31,280
And another 2.5 million children were expected to
die being unvaccinated from malaria, and the main
1354
01:59:31,280 --> 01:59:38,720
constraints to increasing the number of children
who were vaccinated fast was a lack of funding.
1355
01:59:38,720 --> 01:59:44,240
And I remember reading this and finding
it surprising in one sense that this was
1356
01:59:44,240 --> 01:59:49,680
the only constraint. But also, I think,
after everything that we talked about,
1357
01:59:49,680 --> 01:59:56,880
thinking that it was actually not that surprising
and just very depressing. But the fact that if you
1358
01:59:56,880 --> 02:00:04,800
had a few more billion dollars of funding
for Gavi, which supports vaccination in
1359
02:00:04,800 --> 02:00:11,280
countries around the world, you could vaccinate
enough children to save another 300,000 lives.
1360
02:00:11,280 --> 02:00:16,240
The other thing that was interesting to
me about this was that one of the reasons
1361
02:00:16,240 --> 02:00:21,360
that there was this funding constraint
was that one of the countries with the
1362
02:00:21,360 --> 02:00:30,400
highest burdens of malaria was Nigeria. And
Nigeria had just increased its GDP enough
1363
02:00:30,400 --> 02:00:36,400
to be placed in a higher threshold, of a
higher income country, according to Gavi,
1364
02:00:36,400 --> 02:00:44,400
and that meant that they were no longer eligible
for financial support to purchase these vaccines,
1365
02:00:44,400 --> 02:00:48,880
and that meant that a lot of children would
go unvaccinated, and that the cost was just
1366
02:00:48,880 --> 02:01:02,640
so much higher after just passing this threshold.
It seemed very bad to me that that was the case.
1367
02:01:02,640 --> 02:01:07,200
But there is some good news, which is
that there was another deal where the
1368
02:01:07,200 --> 02:01:14,720
price of R21 was reduced from $4 to $3 per dose,
1369
02:01:14,720 --> 02:01:21,760
and that would save around $90 million and
help vaccinate another 7 million children.
1370
02:01:21,760 --> 02:01:27,200
So all in all, what do you each wish
that donors and funders and other
1371
02:01:27,200 --> 02:01:32,560
decision makers understood about vaccine
development that they're getting wrong?
1372
02:01:32,560 --> 02:01:40,320
I mean, I think it's one of these situations where
actually throwing money at the problem would make
1373
02:01:40,320 --> 02:01:48,640
a difference. And that is something that people
might find surprising in other fields, but here,
1374
02:01:48,640 --> 02:01:53,680
funding Gavi would actually go a pretty long
way. Or funding the other types of malaria
1375
02:01:53,680 --> 02:01:58,800
vaccine research would go a long way. I
think that's quite surprising to people.
1376
02:01:58,800 --> 02:02:06,320
I think we should really be learning from
our experience with RTS,S and R21. And the
1377
02:02:06,320 --> 02:02:12,080
biggest problem, with both those vaccines, is
getting all of the doses into the children,
1378
02:02:12,080 --> 02:02:17,600
that they need. So thinking more carefully about
how you develop a product that's deliverable,
1379
02:02:17,600 --> 02:02:24,240
earlier on in development, could have
such a dramatic impact on the impact the
1380
02:02:24,240 --> 02:02:31,920
vaccine can actually have. And I don't
think the researchers doing the work,
1381
02:02:31,920 --> 02:02:37,920
the ones running the very first trials in
humans, are thinking about that enough.
1382
02:02:37,920 --> 02:02:45,120
Right? It's less pizzaz-y, but actually
testing different delivery schedules in
1383
02:02:45,120 --> 02:02:48,240
the clinical trials can have these incredible
1384
02:02:48,240 --> 02:02:52,640
downstream effects of what gets
recommended for millions of kids.
1385
02:02:53,280 --> 02:02:57,120
And maybe it's not fair to put that all on
the researchers and the developers actually, I
1386
02:02:57,120 --> 02:03:02,080
think. They're asking for funding to do the work.
Funding's tight and limited, funders will give you
1387
02:03:02,080 --> 02:03:08,480
the bare minimum, to do the bare minimum. So you
can only test one schedule, and so you have to go
1388
02:03:08,480 --> 02:03:13,360
with what you have the data on already, or what
already looks promising instead of exploring what
1389
02:03:13,360 --> 02:03:21,200
the other options could be. To me, that's also
on the funders to really understand that as well.
1390
02:03:21,200 --> 02:03:27,200
I think another thing is - that people
may not know is just how important it is
1391
02:03:27,200 --> 02:03:33,680
to have clinical trial infrastructure, to have
better ways of running trials more efficiently,
1392
02:03:33,680 --> 02:03:39,840
but also just more sites, more people doing
these tests, being able to test multiple
1393
02:03:39,840 --> 02:03:44,000
vaccines and not having the situation
where people have to prioritize funding
1394
02:03:44,000 --> 02:03:49,040
for one vaccine over the other, at the
expense of testing the others as well.
1395
02:03:49,680 --> 02:03:54,320
But I think there's also another part to
the story as well in that, with malaria,
1396
02:03:54,320 --> 02:04:00,160
everybody knows about malaria. The burden's really
well known. So as soon as a malaria vaccine was
1397
02:04:00,160 --> 02:04:05,120
developed, countries were asking for it. They
knew they had a problem, they wanted the vaccine
1398
02:04:05,120 --> 02:04:09,920
and they're pushing to roll it out to protect
people, so those vaccines can have an impact.
1399
02:04:09,920 --> 02:04:13,040
But there are other vaccines that we've
tried to develop in the past where we
1400
02:04:13,040 --> 02:04:17,280
didn't have good data on the burden in all
the countries that possibly needed it. And so
1401
02:04:17,280 --> 02:04:21,760
I think the Hib vaccine was a good example.
It was developed, it was ready to be used,
1402
02:04:21,760 --> 02:04:26,080
but countries didn't know they had a problem.
So it was this huge delay in rollout. There's
1403
02:04:26,080 --> 02:04:29,280
so much more that needs to be done when
you're thinking about developing a vaccine,
1404
02:04:29,280 --> 02:04:33,840
beyond just developing the product,
thinking about how it's gonna reach people,
1405
02:04:33,840 --> 02:04:43,040
and how people are gonna understand whether
they need the vaccine, what the demand is.
1406
02:04:43,040 --> 02:04:49,280
That was quite an episode. That is our first
episode where we had a expert interviewee with
1407
02:04:49,280 --> 02:04:55,360
us the entire time. Thank you so much, Katharine.
And now it's time to conclude with what some
1408
02:04:55,360 --> 02:05:00,640
of the things, what are some of the things we
learned or that stuck out to us from this episode?
1409
02:05:00,640 --> 02:05:06,800
And I'm gonna start. Number one, how much
you can learn from patents. It turns out
1410
02:05:06,800 --> 02:05:10,560
that there are people who read them and then
they tweak them, and then they change them,
1411
02:05:10,560 --> 02:05:18,000
and then they make new inventions. I mean, that
really gave me hope for public knowledge again.
1412
02:05:18,000 --> 02:05:20,800
That was really cool to hear about.
1413
02:05:20,800 --> 02:05:23,600
Saloni, what did you, what stuck with you?
1414
02:05:23,600 --> 02:05:29,120
So I had a bunch of thoughts. The first
one, which I was thinking about before
1415
02:05:29,120 --> 02:05:34,480
we started recording was that, and
this is a very unpopular opinion,
1416
02:05:34,480 --> 02:05:40,400
but some PhDs are just better than others
and some fields are better than others too.
1417
02:05:41,440 --> 02:05:46,560
I know it's controversial, but I think more
students should go into infectious diseases,
1418
02:05:46,560 --> 02:05:52,960
and should go into vaccine development.
And I have many thoughts about which fields
1419
02:05:52,960 --> 02:06:02,640
should move into those, but I won't name them
- they'll probably, they'll know who they are.
1420
02:06:02,640 --> 02:06:07,760
The other was that I thought it was really
interesting to hear about the Jenner Institute,
1421
02:06:07,760 --> 02:06:14,160
and how it was set up in such a way that there
was a manufacturing facility that researchers
1422
02:06:14,160 --> 02:06:20,480
could work with, and they could learn from
that stage of the process in manufacturing.
1423
02:06:20,480 --> 02:06:26,640
And I thought maybe more institutes should
be set up like this, where you can see the
1424
02:06:26,640 --> 02:06:32,480
both the basic research and the translation and
the manufacturing happening in the same place,
1425
02:06:32,480 --> 02:06:38,960
and learn from these different stages. That I
thought was a really cool thing to learn about.
1426
02:06:38,960 --> 02:06:44,880
The other that stuck with me throughout this
episode was that malaria is very complicated,
1427
02:06:44,880 --> 02:06:49,360
especially compared to the other pathogens
that we've talked about in previous episodes.
1428
02:06:49,360 --> 02:06:54,400
It has many different stages of its
lifecycle, it changes shape. It's harder
1429
02:06:54,400 --> 02:07:00,800
to develop vaccines for malaria than for many
other diseases. And there were various parts
1430
02:07:00,800 --> 02:07:07,120
of that process that were just very tricky
to do scientifically. It was hard to find
1431
02:07:07,120 --> 02:07:12,560
good animal models that helped replicate
what the disease would be like in humans.
1432
02:07:12,560 --> 02:07:21,600
The next was that a lot of the research funding
for malaria was affected by priorities that
1433
02:07:21,600 --> 02:07:29,120
high income countries had. So in the 1950s
during the global Malaria eradication program,
1434
02:07:29,120 --> 02:07:35,520
the funding for research dried up and a lot of
researchers were made program operators in the
1435
02:07:35,520 --> 02:07:44,800
eradication program, and that stalled research
until the Vietnam War, where the US Army troops
1436
02:07:44,800 --> 02:07:52,720
were facing potentially drug resistant malaria,
and there was now a renewed need for research
1437
02:07:52,720 --> 02:07:59,520
into new malaria drugs, but also malaria
vaccines. And that is where the RTS,S vaccine
1438
02:07:59,520 --> 02:08:06,560
originally came from, was research from people
who were working on that during the Vietnam War.
1439
02:08:06,560 --> 02:08:12,640
So that stood out to me as well, that we sort
of think of research happening in the lab,
1440
02:08:12,640 --> 02:08:17,680
but it's really actually influenced by
all of these much broader considerations,
1441
02:08:17,680 --> 02:08:24,320
and the historical context, and things like that,
that I think people don't appreciate enough.
1442
02:08:24,320 --> 02:08:29,200
So the first one for me is
probably the cost, scalability,
1443
02:08:29,200 --> 02:08:33,440
and deliverability are actually really
important. People should think about them
1444
02:08:33,440 --> 02:08:38,880
earlier in the process. I think it's clear
from the R21 and RTS,S experiences that the
1445
02:08:38,880 --> 02:08:43,440
vaccines could have much greater impact
if those things were considered earlier.
1446
02:08:43,440 --> 02:08:50,240
I also thought that just within that
process, it's not just the broader concerns,
1447
02:08:50,240 --> 02:08:56,000
but at every stage of vaccine development, these
things are really important. Like how you develop
1448
02:08:56,000 --> 02:09:02,000
the adjuvants and how expensive those are, or
how that affects the efficacy of the vaccines,
1449
02:09:02,000 --> 02:09:08,560
and how accessible they might be later on as well.
And then things like, how does the dosing of the
1450
02:09:08,560 --> 02:09:17,520
vaccine that's being developed affect how easy
it is to scale it up, across countries, or across
1451
02:09:17,520 --> 02:09:24,640
millions of children, I think is something that
people underappreciate. And then similarly, the
1452
02:09:24,640 --> 02:09:30,800
vaccination schedules - the fact that the malaria
vaccine is taken at different ages than other
1453
02:09:30,800 --> 02:09:37,840
childhood vaccines, and how that affects uptake
of the vaccines, is something that was new to me.
1454
02:09:37,840 --> 02:09:45,840
And just this idea of making things more efficient
at all of these stages could be really important.
1455
02:09:45,840 --> 02:09:53,280
I've been reading the book The Origins of
Efficiency by Brian Potter, and one of the key
1456
02:09:53,280 --> 02:10:00,800
things that stood out to me from that book was
just how much progress we've made in medicine,
1457
02:10:00,800 --> 02:10:06,480
but also engineering, and all parts of life
were from improving the efficiency of things
1458
02:10:06,480 --> 02:10:12,720
that people have already discovered, and that
that stage can often make the difference between
1459
02:10:12,720 --> 02:10:17,600
something that is possible versus something
that's actually used by millions of people,
1460
02:10:17,600 --> 02:10:21,920
and I think that's actually
a huge part of the picture.
1461
02:10:21,920 --> 02:10:27,520
The other thing that I have always been
thinking about is just how different things
1462
02:10:27,520 --> 02:10:31,600
could have been. Like what others, what other
alternative universe we could have lived in,
1463
02:10:31,600 --> 02:10:37,520
if things were different. And the key
things that I think about here are:
1464
02:10:37,520 --> 02:10:41,920
one, how things would be different if
there was more funding. And second,
1465
02:10:41,920 --> 02:10:46,720
how different things would be if there was better
infrastructure for running clinical trials.
1466
02:10:46,720 --> 02:10:52,800
And we talked about a bunch of examples of how
that could have been different. So one, that
1467
02:10:52,800 --> 02:10:59,040
probably would've sped up the developments of the
RTS,S vaccine, the first malaria vaccine. Having
1468
02:10:59,040 --> 02:11:06,320
the clinical trials sites set up earlier, that
would've made a difference. Having more funding,
1469
02:11:06,320 --> 02:11:11,840
that would've made a difference. But then we also
talked about other vaccine candidates for malaria,
1470
02:11:11,840 --> 02:11:19,200
and how more funding for that research could
have changed the picture and sped up the trials
1471
02:11:19,200 --> 02:11:24,160
for those vaccines. And then finally, the
rollout of the malaria vaccines that have
1472
02:11:24,160 --> 02:11:30,000
already been approved could be sped up with more
funding. And that funding was the constraint,
1473
02:11:30,000 --> 02:11:34,960
and still is the constraint, to
getting that out to more children.
1474
02:11:34,960 --> 02:11:40,960
And I think that often people think of
this as purely a scientific problem,
1475
02:11:40,960 --> 02:11:46,240
but I think that's not the case, and
that in many situations when we're
1476
02:11:46,240 --> 02:11:51,840
talking about diseases that affect people and
poor countries, often commercial incentives,
1477
02:11:51,840 --> 02:11:59,200
and funding, and the historical context and all
of these things actually have a very big impact.
1478
02:11:59,200 --> 02:12:04,160
I think it's really easy to look back and think
about how things could have been done differently
1479
02:12:04,160 --> 02:12:09,040
with hindsight. But it's really important
to remember that these were really uncharted
1480
02:12:09,040 --> 02:12:13,840
times for this type of vaccine, and it's really
quite amazing what was achieved over the time.
1481
02:12:13,840 --> 02:12:19,840
Obviously, we all wish things could have been done
faster and can keep going faster in the future,
1482
02:12:19,840 --> 02:12:26,000
but it is quite remarkable what was achieved. But
I think it's important that we do look back. I
1483
02:12:26,000 --> 02:12:31,440
think we should all be looking at the experiences
of the past and learning from them so we can
1484
02:12:31,440 --> 02:12:35,760
improve what we're doing as we're developing
future vaccines; learn from those mistakes.
1485
02:12:36,720 --> 02:12:40,640
And you know, now as a funder, I'm trying
to take a lot of those lessons and those
1486
02:12:40,640 --> 02:12:45,665
experiences and apply them to the development of
next gen malaria vaccines and Strep A (Group A
1487
02:12:45,665 --> 02:12:50,560
Streptococcus) vaccines and any other products
we end up working on at Coefficient Giving.
1488
02:12:50,560 --> 02:12:57,360
What you just mentioned, made me realize that the
alternative universe that we could have lived in:
1489
02:12:57,360 --> 02:13:02,800
it could have been faster, but it also could have
been slower, and I hadn't thought about that.
1490
02:13:02,800 --> 02:13:10,000
I think my main takeaway from looking
backwards into the past today is about
1491
02:13:10,000 --> 02:13:14,800
the present and about the future.
And it's that we live at a time of
1492
02:13:14,800 --> 02:13:23,680
scientific wonder. We - people who invented
world-changing technology are among us today.
1493
02:13:23,680 --> 02:13:30,320
Invention is often a process of building on other
people's work, tinkering, tinkering in the lab,
1494
02:13:30,320 --> 02:13:36,400
and taking care of those lab notebooks, looking
in an electron microscope, trying an experiment,
1495
02:13:36,400 --> 02:13:41,760
changing what you started with, trying another
experiment. And these people are heroes.
1496
02:13:41,760 --> 02:13:46,880
They're real people. Sometimes you can
even get them to come on your podcast,
1497
02:13:46,880 --> 02:13:53,760
thank you very much, Katharine. And to anyone
listening, you may know one of these people,
1498
02:13:53,760 --> 02:13:59,680
and society may not recognize it yet, and they're
still inventing and they're still trying stuff.
1499
02:13:59,680 --> 02:14:05,760
You may become one of these people in the
future. And when it comes to science, we are
1500
02:14:05,760 --> 02:14:11,360
all in this together. We're trying to figure
out what is true and what we should do next.
1501
02:14:11,360 --> 02:14:15,760
So I just wanna end by saying,
Katharine, thank you very much.
1502
02:14:15,760 --> 02:14:22,800
This was very enjoyable and I'm very
excited about everything that comes next.
1503
02:14:22,800 --> 02:14:25,920
Thank you. It's been great
to be here. Great to chat.
1504
02:14:25,920 --> 02:14:31,920
If you enjoyed this episode, you should rate us
on Spotify or Apple or wherever you listen to this
1505
02:14:31,920 --> 02:14:39,520
and share it with everyone you know, including any
parasites that you are currently infected with.
1506
02:14:39,520 --> 02:14:44,160
Maybe they are heroes too, you never know,
they could contribute in their own way.
1507
02:14:44,720 --> 02:14:50,560
Please share this one in particular with
anyone who's considering starting a PhD.
1508
02:14:50,560 --> 02:14:53,520
Yes!
1509
02:14:53,520 --> 02:14:56,240
Great. See you next time everyone!
1510
02:14:56,240 --> 02:14:57,440
Bye!
1511
02:14:57,440 --> 02:14:58,400
Bye!
1512
02:14:58,400 --> 02:15:03,680
Bye!