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Excerpts from a talk by Sir John Vane
(Nobel Laureate, Physiology / Medicine – 1982)
Academic, basic, or "blue-sky" research, holds great promise for
the community and for the health of mankind. But today's urgency to show
a return on investment is leading pharmaceutical companies to demand that
research be project- and market-oriented, so much so that "blue-sky" research
is threatened. This industry threat is very real and is spreading to governmental
funding of academia because of the same short-sighted philosophy.
I will give some examples from my own experience that illustrate the way
in which "blue-sky" research can lead to totally unexpected
benefits for the health of mankind. The first is aspirin.
Just under 100 years ago in the German drug company Bayer, a chemist named
Felix Hoffmann was asked by his father, who was taking salicylate for
his rheumatism, whether anything could be done to improve its bitter taste.
Felix Hoffmann then invented aspirin by adding a simple side-arm to the
salicylate molecule. This was the beginning of Bayer aspirin and nowadays
hundreds of thousands of tons of aspirin are used around the world for
the treatment of headaches, rheumatism, fevers and so on. But nobody knew
how it worked until some 25 years ago.
My laboratory was working on a group of chemical messengers formed in many
parts of the body called prostaglandins. At the time, it was becoming
clear that certain prostaglandins were involved in causing inflammation
and fever. I was writing a review over the weekend at home when suddenly
it occurred to me that maybe aspirin and similar drugs were working by
preventing the body from making these prostaglandins. In the laboratory
on Monday morning, I said to my colleagues, "I think I know how aspirin
works!" I am not a biochemist and so I had never made enzyme preparations
before. I went to the literature and found out something about the enzyme
that makes prostaglandins in the body. I prepared it in a test-tube and
then added different doses of aspirin and other similar substances, including
morphine, as control. I found that aspirin, or an aspirin-like drug, reduced
the production of prostaglandins by this enzyme according to dose.
After repeating the experiment in many different ways in different tissues,
I published the results in the prestigious journal Nature in 1971 and
suggested that the mechanism of action of aspirin and similar compounds
was through the prevention of the formation of those substances known
as prostaglandins. The idea was that prostaglandins were released in pathological
excess in inflammation and if these could be removed, then you would suppress
the fever, pain, and swelling of inflammation. At the same time, we knew
that all aspirin-like drugs tended to irritate the stomach and possibly
lead to kidney problems; therefore, I suggested that these side-effects
were due to the removal of prostaglandins that were essential for the
proper functioning of the stomach and the kidneys.
The theory was generally accepted and has stood the test of time. More importantly,
it was the discovery of the basic mechanism of action that has led to
the use of aspirin in cardiovascular disease.
We have known for some time that heart attacks and strokes are caused by
the inappropriate clumping together of platelets within the circulation.
Platelets are the smallest particles in the bloodstream and their only
function is to stop us from bleeding to death. Normally, when we cut ourselves,
armies of platelets clump together and stick to the walls of the cut,
building up a dam to stem the flow of blood. The same sort of process
may happen inappropriately in a coronary artery or in an artery going
to the brain and cause a blockage, leading to a heart attack or stroke.
After our discovery of how aspirin works, it became clear that the platelet
clumping was due to the formation of a prostaglandin-like substance in
the platelets. Thus, knowing the mechanism of the action, people started
to test whether aspirin may prevent the inappropriate clumping of platelets
which leads to heart attack and strokes.
First of all they started out with large doses, the sort of dose(6 tablets
a day) that was used in rheumatoid arthritis. However, over the years,
clinical trails in the thousands and thousands of people have shown that
only a small dose is needed and that even baby aspirin (75 mg or 1/4 of
a normal tablet) taken once a day is sufficient to prevent the platelets
from sticking together. This is such a small dose that in lectures I jokingly
say that we should keep an aspirin tablet in the bathroom cupboard and
lick it every morning! Indeed, clinical trials worldwide have shown that
taking an aspirin every day reduces the risks of heart-attack or stroke
by up to 50%. So there are many thousands or even millions of people alive
today because they take a daily aspirin for the prevention of heart-attacks
and strokes. These poeple would not otherwise have been with us had I
not done that crucial experiment on a Monday morning. That is directly
a result of our "blue-sky" research.
My second example comes from the same family of prostaglandins. Anatomists
over the generations have known that blood stays fluid in healthy arteries
but clots in dead ones. This was never understood but we also knew that
the very same platelets that I have been talking about do not normally
stick to the inner healthy walls of arteries. In 1976, we found that this
was because the inner walls of the arteries make a prostaglandin, which
prevents the platelets from sticking to them. We called it prostacyclin
and this work opened up an enormous field of research. We now think that
platelets stick to arteries when compounds such as prostacyclin failed
to be formed. However, the therapeutic importance of this finding is that
prostacyclin-like substances are now being marketed for use in obstructive
vascular diseases such as those that normally lead to foot or leg amputations.
My third example shows how a new important kind of drug can come through
serendipity, international collaboration, and of course, "blue-sky" research.
In the mid-1960s when I was working at the Royal College of Surgeons in
England, I had an application for a post-doc position from a Brazilian
scientist named Sergio Ferreira. For his PhD, he had worked on the venom
of a particularly nasty Brazilian snake called Bothrops Jararaca. He had
shown that extracts of this venom contained small peptides that potentiated
the action of a pain-producing substance in the venom called bradykinin,
probably by enzyme inhibition.
He came to my laboratory carrying some of his venom extracts in his pocket.
I suggested to Sergio that we should study his snake venom extract on
the renin-angiotensin system, so called because an enzyme known as renin
is released from the kidney into the bloodstream and thus leading to the
formation of a very strong pressor substance called angiotensin. However,
he had other plans. He wanted to continue his work on bradykinin, and
being a forceful personality, he convinced me to let him do that.We worked
together on bradykinin for two years, and only at the end of that period
did I persuade another colleague, Mick Bakhle, to test the snake venom
on the renin-angiotensin system. It turned out to be a potent inhibitor
of a key enzyme- angiotensin converting enzyme (ACE) in that system.
At the time I was consulting with Squibb in New Jersey. Nobody knew whether
angiotensin was important in high blood-pressure even though it was suspected.
I suggested to Squibb that this inhibition of ACE by the snake venom peptide
would test the concept as to whether angiotensin was involved in high
blood-pressure or not. Scientists at Squibb were enthusiastic and started
a programme to isolate the active venom peptide. The marketing people
were unenthusiastic because they could not see a market for an anti-hypertensive
compound that had to be injected, as a peptide would.
I visited Squibb three times a year and each time found that I had to re-infuse
enthusiasm into the programme. It was almost dropped because of marketing
pressure. Eventually, they made a kilogram of the peptide from the snake
venom, which was shown in New York by John Laragh to reduce a high blood
pressure. Thus, the concept had been proven. Now if only a similar compound
absorbed by mouth could be found, there would be great therapeutic potential.
Having introduced the programme to Squibb and kept it alive for several
years, I then joined Burroughs Wellcome, a competing pharmaceutical company,
as the R & D Director, thus allowing me to no longer consult with
Squibb. Nevertheless, a few years later their own scientists had discovered
an orally-active ACE inhibitor, which they took to the market calling
it Captopril or Capoten. Merck also found an ACE inhibitor around two
or three years later, which they called Enalopril or Innovace. I have
a paternal pride in the fact that these two compounds alone now have $20
billion worth of sales per annum around the world. That would not have
happened without the "blue-sky" research on the snake venom
which started in Brazil and then went on in my laboratories in London.
There were so many extraordinary coincidences that were needed in order
for that process to fructify, including Ferreira's choice to visit my
laboratory rather than Oxford.
With these examples, I hope that I have begun to convince you that breakthroughs
in medical science must come from "blue-sky" research. Without
it, and without public support for it, society would be poorer as would
our health. And taken in perspective, "blue-sky" research is
not all that costly compared with the development process following it.
Of course, the whole process of drug discovery takes many years and the
work of many hundreds of people - a whole sort of inverted pyramid of
costs balancing on the much less costly, but inescapable, "blue-sky" research.
Without this fundamental research, important drugs such as antibiotics,
the betablockers, the H2 antagonists, and the calcium channel blockers
would not now exist.
An especially fertile area for basic or "blue-sky" research is,
of course, the brain. This has been left last by scientists because of
the enormous technical difficulties of studying the brain. The kind of
exploration of how nerves work and how brain cells communicate with each
other is being studied by Dr. Bazan's Neuroscience Center and is vital
for our future understanding of how the brain works. Without it ,we shall
not find effective cures for strokes and neurological diseases, such as
Alzheimer's, as well as problems, such as schizophrenia, epilepsy, and
depression that are so empirically treated by present-day drugs.
Over the last 40 years or so, I have visited many laboratories around the
world. Here in New Orleans, you have excellent universities and the LSU
Neuroscience Center, which is led by the enthusiasm and energy of Nicolas
Bazan. It is a real centre of excellence and is recognized as such around
the world.
About Sir John Vane, FFS:
- Nobel Prize in Physiology / Medicine (1982).
- Director of Research
and Development at the Wellcome Foundation.
- Founder,
Chairman and Director General, The William Harvey Research
Foundation (London).
- Fellow of the Royal Society.
- Knighted in 1984
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