An HIV vaccine is what the world needs now

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i’m a laboratory-based scientist

and for the last 25 years of my career

i’ve been trying to make a vaccine to

hiv

and now we have three vaccines for

covert

in less than a year how did this happen

well the covet vaccines benefited a lot

from the the years of investment

in hiv vaccines and what i want to tell

you about today

is how we can use that momentum to speed

up the development

of an hiv vaccine but first let’s look

at these two viruses

they certainly have some similarities as

you can see they are small microscopic

viruses and you need very powerful

microscopes to see them

but there’s also some significant

differences so

sar’s curvy ii which is the virus that

causes covet 19

is spread via the respiratory root so

that’s simply breathing

and it means that everybody is

susceptible this virus causes an acute

infection

that means it’s very short-lived and the

body is able to clear the virus

and as we know most that happens in most

people

and that’s because our bodies make an

immune response to the virus

particularly neutralizing antibodies

which develop in almost

everybody another important feature is

that this virus

is very stable so the 60 million people

around the world that have been

infected with this virus are infected

with a very related virus

there are some differences but it is

very similar

now hiv in contrast causes a chronic

infection

and that means it it’s it’s a lifelong

infection

and that’s because this virus integrates

into

our genetic material into our dna

the other major factor is that the

neutralizing antibody response here is

very slow and ineffective and then

another major

hurdle for hiv vaccine development is

the virus mutates and it really is a

moving target

now vaccines have been one of our most

successful ways of dealing with

infectious diseases

and most vaccines work by in inducing

neutralizing antibodies these are part

of our immune response

and neutralizing antibodies work because

they

specifically bind to parts of the virus

in this case it’s the spike protein

which surrounds the

um the sars cov2 particle

so it’s actually a physical interaction

the the antibody

binds to the spike and stops the virus

from infecting cells and that’s what it

means by

uh by neutralizing so let’s have a

closer look at this

sars covi2 protein so this is what

causes the spikes or the corona around

the virus

and scientists have been able to

look at this at what’s called a very

high resolution and in fact

again it’s hiv scientists who turned

their attention

to looking at the sars curvy ii

protein partly that’s because of the

urgency but also because a lot of

funding was made available

for people to study covert 19. but

what we what we’ve learned from from the

structure

of the spike protein is that the the

part that’s targeted by the antibodies

is a very focused part that’s the part

that’s colored in

in red and so that is the major target

that we’re looking

because that is the part of the protein

that binds

to the cells now

a number of different vaccines have been

made against covet 19

and again it’s really benefited from the

vaccine development that’s been taking

place for for decades

with hiv and so this just shows you some

of the different approaches that have

been taken

and many of you will know i think then

our household names some of these uh

these vaccine manufacturers so the

genetic vaccines which are

composed of the rna or the dna

of the virus of the spike protein are

used to stimulate an immune response

these same genes are also put into what

is called a viral vector

so it’s a harmless virus to actually

carry these genes into the body

almost like a trojan horse so in these

kinds of vaccines

the body is in fact making the spike

protein

we’re actually making our own vaccine in

a way

the third kind of vaccine is called a

protein vaccine

and this is where we make the protein in

the laboratory and then

you know use that to immunize people and

this is a much more traditional

approach to vaccine development and it

it’s it’s it takes a lot longer and is

actually much more expensive

so there’s certainly and it’s been

widely reported in the media

about you know this incredible effort to

develop

a covert vaccine and now we know we

already have three

that have shown that they work that they

have a high level of efficacy

the two rna vaccines were shown to have

over 90

efficacy and the vectored vaccine

was also had very good efficacy but as

you can see from what’s called this

pipeline

there are another 10 that are still

undergoing testing and certainly are um

you know we we suspect that they’re also

going to work

and you can see that in the earlier

phases of of testing there are a large

number of vaccines so we have a very

very robust pipeline

for covert vaccine development and

although none have been licensed as yet

that is also very very imminent

in contrast in the 20 years

of doing hiv vaccine trials we’ve only

ever done

six efficacy trials um in the in in 20

years so

just to give you a sense of uh you know

the difference uh

and how we’re tackling these two viruses

but i don’t want to make it sound as if

hiv vaccine development is easy because

it isn’t it’s actually one of the

biggest challenges of our time

and that’s really because this virus

does change

so we the laboratory that

that i run at the at the at the nicd

has been looking at how to develop these

broadly neutralizing antibodies in

infected people

and we discovered during this process

that the virus

is changing to create the kinds of

stimuli that you need to to get the

right kinds of antibodies

and so this this evolutionary process

is now being incorporated into vaccine

design

and so the the the paradigm is is that

we’ll need to have different

different vaccines in order to shepherd

the antibody response along so it can

become

a neutralizing antibody response and

that’s just shown graphically here

um so the um this is the

the the equivalent of the spike protein

in hiv is called the envelope protein

and so each of those different colors

shows that it’s a slightly different

envelope protein

in order to to basically as i say coax

the immune response along the right

pathway to make neutralizing antibodies

so certainly in terms of vaccine

development you know hiv presents

you know some significant challenges so

i

am participated in a covert vaccine

trial

the novovax trial that’s been run by

this university

and i did that because i really believe

in vaccines i believe in the power of

vaccines

and also because i am vulnerable just

like everybody else to

you know to being infected by sales

curvy 2.

and so i had two vaccinations

and you know i sort of imagined this uh

protein circulating in my body and my

b cells trying to you know hunt it down

so it could

produce the right kinds of antibodies in

order to you know to protect me

um and uh you know during this time one

kept one keeps a vaccine diary

you keep track of your um you know your

temperatures where there’s any swelling

or redness

and there really was very minor uh

pretty similar to an insect bite

that really resolved within a few days

um

of course i don’t know yet if i’m on the

placebo or the active arm of the

of the vaccine that will only be be

found out later

and that’s really a critical thing for

um

you know for determining how a vaccine

works is to measure the immune responses

in people who’ve been vaccinated

and to determine what’s called the

correlate of protection so we need to

know what levels of antibodies

the vaccine needs to stimulate in order

to protect people from infection and

that’s what these trials are going to

show

so a very critical thing and in fact

once we have the correlate of protection

actually the vaccine development process

is going to speed up even further

but i also you know like you know we’ve

been learning as we go

with this epidemic that we still have

many unknowns

so we don’t know how long immunity is

going to last we don’t know if these

vaccines are going to work for everybody

um though there’s certainly good signs

that they do work in older people who of

course are a major target group

um we’re not sure if we’re measuring

exactly the right immune responses

um because there may be other things

that we

you know are still to discover and i

think a very critical thing is um

you know will the virus change in the

same way that it changes with hiv

and represent a problem you know once

the a number of people

um have immunity to sars it’s going to

put pressure on the virus and so that is

one of the things that we certainly need

to keep

track of so now i want to look at the

global devastation caused by these two

epidemics so the top

graph shows the number of deaths caused

by sars kovi ii per week

since the start of the outbreak and what

you can see is in the purple is the

first wave that occurred in europe and

you can see the resurgence now that’s

happening

and then you can see the high level

and ongoing uh level of deaths in the

americas

and what is most um disturbing about

this graph

is that these the resurgence levels are

higher than the initial levels

and really speaks to our the urgent need

to start deploying these

um active these efficacious vaccines

because if we don’t um these waves will

keep happening

this virus will become endemic and it

will keep spreading amongst susceptible

people so so far

in 11 months 1.4 million people have

died of covet 19

and we certainly don’t want to be

getting to the levels that we see with

hiv

of 35 million people so

the reason why there’s 35 million people

who have died from hiv is because hiv

has been with us for a very long time

and as you know we don’t have a vaccine

but what we do have is we do have good

antiretroviral therapies

and you can see the effect of those on

on the graph below

so at the peak of the aids epidemic

approximately 1.6 million people were

dying per year

and that decline was when antiretroviral

therapy started being widely used

but we it’s not going to get us to zero

because antiretroviral therapy treats

infected people what we need

is we need to prevent people from

getting infected and that’s why we need

a vaccine

so we need that vaccine to get that

curve right down

just last year 2019 over 700 000 people

died of hiv so the other important thing

about this graph

is the colors so you can see that

that it’s mostly red and that’s because

hiv

is mostly affects the african continent

but it also we also know historically

that

vaccine development or africa has been

very neglected in terms of developing

vaccines for diseases

that affect the african continent

so what can we learn from covet 19 that

will help us to develop

an hiv vaccine more rapidly so

what we need to be doing is testing

developing and testing multiple

candidates

we need a robust pipeline the same way

that we’re doing with covert we need to

be testing lots of different concepts

um testing them all at the same time we

certainly need to be testing the mrna

vaccines

um which were originally developed for

hiv but you know now are being tested

for covert we need to go back

and we need to be doing that we also

need to run parallel processes so while

we’re testing we need to be

manufacturing and we need to be seeking

approvals

it’s high risk but it’s

it’s it’s it fast tracks the process and

we certainly need more money

so covert 19 the amount of money spent

on covert 19 is 8 to 10 times higher

than the funding for hiv vaccines in any

given year

and we know that money drives innovation

it attracts

the best scientists and the best

industries into the

um you know into this area um

it helps us run more trials vaccine

development is expensive and it is

higher risk

we also need more industry involvement

we’ve certainly seen that in covet

many industries including industries

have never been involved in vaccine

development

are now getting involved but we do need

to incentivize them

and and one of the ways to incentivize

them is of course to give them advance

commitments

um so our governments need to do that

they need to say that we will buy the

vaccine

uh if it’s shown to be safe and

efficacious

there’s no doubt um that the covert

vaccine is going to have a major impact

it’s going to turn this epidemic around

it’ll save lives and it’ll save

livelihoods

what we need now is to also develop a

vaccine against hiv

so that we can do the same we need to

attract the best

people into this area we need to use

what we’ve learned

in developing covert vaccines we need to

apply that to hiv

so that we can have an aids-free world

thank

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you