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INTERVIEW - David Ho |
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| "We have realized that care and support
have an impact on prevention efforts" |
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| Do you think the government
in China is now committed in its response to the HIV/AIDS epidemic? |
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| I think, at the top level, that is, at the State Council with
the Vice Premier and at the level of the Ministry of Health
and its leadership, the commitment most definitely is intense.
We've also been doing our advocacy work and it's probably a
combination of many events, including SARS that has improved
the political will to do something about HIV/AIDS in China.
Certainly, we saw the symbolic gesture that the Chinese Premier
made on World AIDS Day by visiting people living with HIV/AIDS. |
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| But even more important than that, Vice Premier Wu Yi spent
several days visiting villages with severe AIDS problems in
the central province of Henan and this was done quietly, under
the radar screen. |
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| It is clear that the government is restructuring its AIDS
effort so that it reports to the State Council, elevating the
status of this office. So I see a lot of changes but, of course,
China is a huge country and a lot of the high-level commitment
will take some time to trickle through the system. |
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| Do you think there's a change of attitude
towards AIDS in China within the general populace, that it's
not seen just as a problem in marginalized communities? |
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| There has been some improvement, although there's a lot more
that has to be done. I think the leadership is aware of the
situation and will be making the right decisions. But unfortunately,
if you speak about the Chinese population in general, I think
most do not know anything about HIV/AIDS; most do not care.
Most consider it a "foreign disease" or an epidemic
that affects "strange" populations. So there's now
a disconnect between what the leadership knows and would like
to do, and the general population. And I think that will require
tremendous educational and outreach efforts. |
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| You mentioned your advocacy work, were
you referring to your own Chinese AIDS Initiative? |
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| Yes, we've been organizing a consortium to help China address
its HIV/AIDS problem because we wanted to approach the problem
in a very comprehensive manner, with prevention at the center,
including testing. Of course, this is prevention outside the
vaccine research agenda. But we have also realized that there
are other multiple components that will have an impact on this
primary agenda of prevention; that is, we have to deliver care
and services and, importantly, Anti-Retroviral (ARV) therapy
to help bring people into the prevention effort. We have been
implementing the ARV component with the Clinton Foundation. |
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As for advocacy, it's actually broader than that-it's advocacy,
outreach and education and also involves issues related to
legal reform and policy changes. We've been working with the
schools of journalism, law and public policy at Tsinghua University
in Beijing, the leading educational institution in China.
We have a series of things in mind including training of the
Chinese political leadership and media with courses done at
Tsinghua. We're going to make documentaries and public service
announcements.
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| At the end of last year, November 10th, we organized a high-profile
conference that involved former President Bill Clinton. It was
a very successful event that immediately preceded all these
positive changes with the Chinese leadership. AIDS was prominent
on the agenda for the Chinese for weeks, so I suspect it all
had a pretty positive influence. |
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| How are AIDS vaccine trials viewed in China,
and are they something that your initiative and other Chinese
groups are gearing up towards? |
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| The Chinese government has always emphasized science and technology,
so they welcome taking vaccines to China for testing. There
are internal efforts underway by various Chinese investigators,
particularly in collaboration with European scientists. |
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| We've been speaking to the Ministry of Health and the State
Drug Administration for some time now. They know that our two
vaccine candidates are derived from a strain from southwest
China, the Yunnan province, and that we have taken them through
laboratory testing, some animal testing and now one is approved
[for investigational use] by the FDA and another one will be
submitted soon. |
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| Which vaccine candidates are those? |
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| Our first vaccine consists of two DNA vaccines mixed together,
which will express five HIV proteins; Gag, Pol, Env, Nef and
Tat [called ADVAX]. We've done the in vitro evaluation, the
immunogenicity studies in animals, and this was taken to the
FDA last year and approved [for study in humans]. We launched
the clinical trial here in New York late last June, and we've
just finished enrolling two dose schedule arms, and we have
a third dose coming up, probably in May. |
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| So that vaccine is well on the way. In terms of the regulatory
aspect, we've been speaking to the Chinese State Drug Administration
and working with a vaccine production facility in China to think
about the next steps in production there. We need to finish
the Phase I here, then we will take this initial product to
China. |
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| The second product is a modified vaccinia Ankara (MVA), which
contains the same five genes from the same subtype C strain
of HIV from southwestern China. For this one, we've done the
laboratory evaluation and animal testing, and we have a GMP-grade
product that's now in preclinical testing. We're also doing
some QA/QC (Quality Assurance/Quality Control) studies and we
plan to submit it soon to the FDA. We believe this is one of
the best vaccinia vaccines out there-it's stable, it expresses
well, it's easy to grow, easy to produce to high titers. So,
fortunately, we haven't had the technical problems that have
plagued others in MVA development. It's gone well and we're
anxious to get it into the clinic. And once again, we'll be
testing in New York. |
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| The work on both of these vaccines was made possible by support
from International AIDS Vaccine Initiative (IAVI), which has
been absolutely vital to our vaccine efforts. We had some internal
funds that got the project off to a good start but IAVI stepped
in fairly early and has supported us for the past three years,
and that's been great, to be able to take it from the bench
to the clinic in that short period of time. But it isn't just
financial support. Especially in the past year, IAVI also provided
clinical research expertise that complemented our basic scientists
here, particularly with respect to development issues and regulatory
concerns. If it weren't for that, we'd be struggling. So it's
been a very successful partnership and we certainly appreciate
that. |
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| What's your opinion of the current state
of Chinese research in HIV? Is there a new funding commitment
from the government? |
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| Although there is a deeper commitment on the part of the government,
I don't think it has trickled through the system to be translated
towards research efforts. So there isn't a lot of basic HIV
research in China, in fact there's almost none. But people are
beginning to be more interested in more practical issues in
treatment, vaccine development, prevention work and the clinical
and epidemiological front. |
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| What is the current state and the potential
future use of manufacturing facilities for ARVs in China? Is
making their own generic ARVs an important pursuit of the government
and public health bodies? |
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| Yes, there are some pharmaceutical companies involved that
are government- owned or government-backed. The Northeast Pharmaceutical
Group, for example, has made several generic drugs. And now
the private sector is trying to do more. There is a company
in Shanghai called Desano [Bio-pharmaceutical Co.] that has
made four generic drugs- AZT, ddI, D4T and nevirapine. These
are now approved in China and they're fairly cheap. I think
some studies remain to be done to demonstrate bioequivalence
to the western drugs, but at least part of the therapeutic arsenal
is being synthesized in China. |
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| We also have to keep in mind that China has for some years
now had an active, not pharmaceutical, but a chemistry effort
to make the basic components that are the precursors for ARV
drugs. We hear so much about Cipla in India or the Brazilian
effort, but we have to keep in mind that these places get their
basic components from China; they have played a role through
that particular function. Now they are trying to expand the
process and go on to make the actual drugs. I think it will
happen. I'm hearing more and more about other, mostly private
companies trying to join the effort. |
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| However, to date China has been respectful of World Trade
Organization regulations with respect to intellectual property.
So Desano and the Northeast Group have just made generics or
drugs that are off patents or not covered by patents, they have
not gone on to make 3TC, for example, which is patent-protected
in China. |
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| What do you think are the most important
goals for China in terms of its AIDS epidemic in the next five
years? |
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| The most important goal is to make sure the projected numbers
of people infected with HIV do not come true. By 2010, the World
Health Organization and UNAIDS have suggested that China will
have 10-20 million infected, going from approximately one million
today. That's a frightening prediction. So the most important
goal is to make sure that it doesn't happen. And for our own
Chinese AIDS Initiative, we want to reduce it by several-fold. |
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| But to achieve that goal, I think the most important thing
is to get the information out to the public. You know, here,
really, more than anywhere else, knowledge is power and we have
to educate the populace about HIV/AIDS and about prevention. |
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| What do you consider are currently the
most pressing scientific challenges for HIV research? |
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| I would say development of a protective vaccine is the highest
priority in AIDS research. That's mine, and I think many would
agree with me. |
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| Aside from a vaccine, I think that developing better drugs
is still an important priority. It's clear that combination
therapy has been great for American and European patients, but
the drugs still need to be improved; there's development of
resistance in some patients, and these people need other options.
We need drugs that have fewer side effects and are easier to
take. So there should be continued incremental development in
the therapy side. |
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| The greatest challenge on the therapy side is whether a cure
could be obtained or not. There's always a lot of debate on
that. I think we all know that it will be exceedingly difficult,
given the fact that the virus is now known to be hiding in a
subset of CD4+ T cells. How to purge the virus from that subset
will be extremely difficult, but probably not impossible, and
so [research] groups have to continue to try. But right now,
I can tell you, we can't think of too many things to do along
that front. If we could think of something that was reasonable,
we would be jumping on it and pursuing it. |
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| Also, there's still a lot of molecular biology that needs
to be defined. Recently, we've learned quite a bit about innate
cellular factors that restrict HIV replication, and these things
are wonderful, such as the APOBEC3G story or the TRIM5a story
that came out only a few weeks ago. These things are wonderfully
revealing about the basic biology of the virus and about how
the host fights various pathogens. |
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| But that said, the most important thing is to make sure we
develop a vaccine to curtail the further spread of this epidemic.
The vaccines that are fairly advanced in development have failed,
and now we're looking at vaccines mostly at early stages of
development. We could optimistically think that these might
offer partial protection, as we're seeing in monkeys with some
of the vaccine candidates. Will they be the home run that everyone
is looking for? I wouldn't be overly optimistic about that.
So I think the next three to five years will be most interesting
to see this whole series of DNA or viral vector vaccines advance
to efficacy trials. |
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| This article was reprinted from the (8(1),February-April
2004, published online before print 7 May 2004) issue of IAVI
Report, published by the International AIDS Vaccine Initiative
(www.iavi.org). |
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| About
David Ho |
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