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HIV HERALD
Publication from the National Treatments Project --
Australian Federation of AIDS Organisations
PO Box H274, Australia Square,
Sydney NSW,  2000
Australia

Tel : [phone]
Fax : [phone]


August 1994
Volume 4 No 8

<Yokohama 1994 Report from the International Conference on AIDS
     New Antivirals
     Markers of Viral Burden Nearing Clinical Use
     Long Term Non Progressors
     Influence of Viral Variation on Disease Progression
     Gene Therapy
<Robert Gallo's Look Toward Future Research
<Bits of News From Yokohama
     AZT is not Recommended in People with CD4 Counts above 500
     Five Year Follow Up Study of ddI Patients with Advanced HIV Infection
     ddI is More Effective in Combination with AZT
     d4T (Stavudine) Results from a Large Clinic in the USA
     Concerns about Flu-vaccinations in HIV Positive People
     Results from an Australian Pilot Study of Ateviridine (U-87201E)
          for Treating AIDS Dementia Complex
     Results from Studies of Long Term Non Progressors
     Results from RGP160 European Trial
<NEWS
     Vaccines - Where are we Now?
     Viral Load Measurements becoming an Important Surrogate Marker
     Aspirin may be a Treatment for HIV
     Rifabutin Approved for Treatment & Prophylaxis Against MAC
<CLINICAL TRIAL NEWS
     Protease, AZT and ddC Combination Trial Results
     Human Growth Hormone Trialled Against HIV Wasting
<NUTRITION
     Zinc Supplementation may Decrease the Number of Opportunistic Illnesses



YOKOHAMA 1994 Report from the
International Conference on AIDS
By Tony Maynard

The Tenth International Conference on AIDS which was held in Yokohama in early
August was not expected to reveal any ground breaking treatments for HIV, but I was
agreeably surprised with the possibilities which were opened up, not only for newly
infected people but also for people who have been considered late stage.

New Antivirals
Firstly, after a decade of these International Conferences, it seems that the era of
expecting AIDS breakthroughs is over and the world will have to be patient with the
gradual advances in treatments for HIV. Of particular note were the better than
expected findings on a new class of drugs called the protease inhibitors.

Although they developed resistance when used by themselves, when used in
combination with nucleoside analogues such as AZT, ddI and ddC, they produced
sustained rises in CD4 and significant reductions in viral load. Unlike the earlier drugs
which interfere with the reverse transcriptase enzyme of the virus, the protease
inhibitors target a different part of the virus' life cycle wherein the "protein cutter"
enzyme called protease which chops large chunks of protein into smaller pieces, (ready
for assembly into a new virus) is suppressed by the protease inhibitors. So far protease
inhibitors have shown almost no clinically significant side effects including those to the
heart, liver and kidney.

Currently, some 20 different protease inhibitors are at various stages of development.
The first of this class of drugs, Roche's  saquinavir, reported excellent results in
combination with AZT and ddC. This triple combination was associated with increased
CD4 counts and decreased viral load, superior to dual therapy with either AZT + ddC
or AZT + saquinavir. Tolerance to all three regimens was similar. Now trials are needed
to test clinical endpoints which will include patients who are antiretroviral naive.

Adding AZT to 3TC monotherapy results in decreased viral burden and increased CD4
counts, according to a presentation from the Academic Medical Centre in Amsterdam.
In vitro (in the test tube), AZT and 3TC exhibit synergy against HIV, but 3TC
monotherapy exhibits high level resistance due to a mutation at codon 184 of reverse
transcriptase. This mutation counteracts the effects of AZT resistance in vitro, so at
least in theory, resistance to this dual combination is unlikely and to date has not been
seen in vivo (in humans).

Markers of viral burden nearing clinical use.
With the increasing number of new antiretroviral agents about to enter clinical trials and
an increasing focus on combination therapies using up to four different drugs, it will
become practically impossible to run and complete large clinical studies with in excess
of 1000 participants which rely on hard clinical endpoints such as the development a
new AIDS-defining illness or death. Therefore, the establishment of true surrogate
markers of therapeutic efficacy has become perhaps the highest priority in the AIDS
clinical trial arena.

The previous reliance on CD4 cell counts as a surrogate marker may soon be
superseded by direct measurement of the viral burden in peripheral blood using
quantitative PCR or branched-chain DNA (b-DNA) assays. This is not to say that CD4
counts will not be important predictors of progression, but by adding this new measure
of actual viral replication, it will be possible to determine the number of copies of virus
being produced. Until now, many investigators believed that plasma viral burden would
be an effective surrogate, but data supporting this belief was lacking.

In several of the sessions at this meeting, researchers have begun to show, for the first
time, that changes in viral burden in response to antiretroviral therapy are predictive of
clinical outcome in clinical trials.

In a session on Tuesday afternoon, Douglas Mayers of the RV43 study group, reported
on plasma RNA measurements as predictors of clinical outcome among people receiving
AZT monotherapy. 100 HIV positive people from the US military participated in the
study. Serum HIV from the cohort was tested for sensitivity to AZT, the codon 215
mutation (associated with resistance to HIV), syncytium inducing phenotype (SI) and
viral burden via plasma RNA was measured by RT-PCR.

Low haematocrit (less than 35%), low CD4 count (less than 200), viral resistance to
AZT on entry into the study and high viral burden were all correlated to increased
probability of dying. People with less than 1,000 copies of RNA per millilitre had little
risk of death, while those with greater than 10,000 copies per millilitre had a 40% risk
of death within one year.

Viral burden was also correlated with AZT resistance; less than 1,000 copies per
millilitre were associated with no evidence of resistance, and greater than 10,000
copies per millilitre were associated with the appearance of resistance at 38% per year.
Low haematocrit, low CD4 counts, and SI phenotypes were also correlated with an
increased likelihood of resistance to AZT. Mayers noted that as an independent
measure, the SI phenotype was NOT predictive of adverse events such as opportunistic
illnesses or death, but was associated with increased resistance to AZT.

In the discussion session led by Jay Levy from the University of California, San
Francisco, participants said that direct viral quantitisation appears to be a promising
method of following a patient's course of illness. It was noticed that the quantitative
competitive PCR assay (Roche, Genelabs) would probably prove to be more useful
among early stage patients, while the bDNA assay (Chiron) would be useful in late
stage patients. While viral load has been shown to drop in response to various types of
antiviral therapy, the absolute correlation between reduced viral load and improved
clinical outcome still remains to be firmly established. Nonetheless, the studies
presented have generated much hope for the use of these markers not only in clinical
trials but also as potential tools in the day to day management of patients in the clinical
setting.

Long Term Non Progressors
A recurring theme for discussion at this year's conference has been the subject of the
long term non-progressor. Up to 10% of people infected with HIV for over 13 years in
some cases remain healthy with CD4 counts and other immune function markers
remaining within normal limits. Attention has been focused on virologic and
immunologic features of these people in the hope of finding some viral or host factors
which would inspire effective new research strategies. The role of cell-mediated
immunity in controlling viral burden was the subject of one study on the immunologic
and virologic characterisations of healthy long term non-progressors by the San
Francisco AIDS Office. Compared with recent seroconverters, healthy long-term HIV
positive men from the San Francisco City Clinic (SFCC) cohort have higher CD4 counts,
CD8 counts and CD4 slopes, as well as vigorous and sustained cytotoxic lymphocyte
(CTL) responses.

In a presentation by Phillippa Eastbrook from the Chelsea and Westminster Hospital in
London, the nature of the initial CD4 responses appeared to distinguish a group of non-
progressors from those people with more rapid disease progression. Additionally, high
and sustained CD8 counts,  and specific CTL activity correlated with non progression.

Influence of viral variation on disease progression.
Contrary to previous reported data, non syncytium-inducing (NSI) isolates may lead to a
higher viral load and disease progression in the presence of neutralising antibodies
according to Jaap Goudsmit of the Academic Medical Centre in Amsterdam. These
researchers have also been working on defining correlates of disease progression,
including CD4 count, viral load, SI versus NSI phenotype, replicative capacity and viral
susceptibility to neutralising antibodies. This group also found that viral load may be the
most important factor in disease progression.

In their study, progressors with the highest viral load progressed most rapidly,
regardless of phenotype. The lowest viral load was found in the long term non-
progressors. According to Goudsmit, it was surprising that the NSI progressors have
the highest viral load of all the groups that were studied. In looking at this phenomenon
more closely, he found that some NSI isolates replicate more rapidly than SI isolates.
However, SI isolates eventually escape the antibody control, resulting in viral loads
similar to those seen with NSI progressors. The determinants of a switch from NSI to SI
phenotype occurs within the HIV envelope and the relative risk of progression with SI
virus is six times that of NSI isolates. Nevertheless, 50% of people who progress to
AIDS have NSI isolates.

Gene Therapy.
In a plenary session on Wednesday, Dr. Flossie Wong-Staal of the UCSD presented her
work on gene therapy for HIV infection. The basis for this derives from the fact that in
HIV infection, the virus makes use of the host cell genes to replicate itself. In gene
treatment, the hope is to create in the laboratory a gene that is defective for HIV
replication, but does not itself affect the host cell function.

Then the gene will be attached to viral DNA which does not replicate in humans, and
then be "infected" or transducted into the infected person's lymphocytes and
macrophages. These altered cells which are resistant to HIV are then re-infused  into
the person and would gradually replace infected cells, eventually leaving HIV without
any susceptible cells to infect.

The problem with this therapy however, is that it would need to be started at the time
when the immune system has not been irreparably damaged. Wong-Staal's group has
succeeded in creating a ribozyme gene which is able to chop up viral RNA when
inserted into the cells of infected mice. Before this technique can be said to be effective
in humans, it would need to be successfully inserted into stem cells (the parent cells of
all blood cells) which would eventually differentiate into mature macrophages and white
cells.

So where will gene therapy go from here? There are three directions being pursued
currently. First, is to continue to refine the gene constructs and delivery vectors.
Second will be to test these in vivo in animal models, and then finally to proceed to
phase 1 clinical trials in humans. Although still in its early stages, gene therapy is an
exciting development. However, it will be several years before it can be applied to HIV
treatment.

In summary, Dr. Wong Staal reminded us that 'so far gene therapy has not cured
anyone of anything.'


Robert Gallo's look toward future research
Adapted from plenary lecture by Dr. Robert Gallo
By Ian McKnight-Smith

Robert Gallo, a prominent researcher from the National Institutes of Health in the United
States, presented a state of the art plenary session at the recent Yokohama AIDS
Conference. This article will summarise the points that he made at this session.

The current pessimism of patients and the frustration of people with HIV is due in part
to the enormous progress over the early years of research. With this came the
expectation that HIV would be relatively easy to control and hopefully cure. However
this has not turned out to be the case and in recent years research reached a clear
plateau.

This has forced a review of the whole question of AIDS research and to determine
which ways research should go to from this point on. Ideally it would be great if we
had an endless resource of people and funding to research all areas of promise, but this
is not possible, and some priorities clearly need to be set. However this is not to say
that there should not be an increase overall in research dollars being invested in this
area, because it would not be just HIV that stands to benefit. There are many other
associated disciplines of medicine that will change as our understanding of how to
control this virus increases.

So at this point in time there are some critical questions to ask:

     Should we advance our research into vaccines?

     If we can block HIV replication will we stop progression to AIDS?

     Can we ever prevent or control escape mutation by HIV(ie treatment resistant
     strains)?


Vaccine research advancement.
"We badly need much more information on the human response of uninfected people to
candidate vaccines" said Dr. Gallo. "However, such trials were recently stopped
because the candidate vaccines employed purified HIV-1 envelope proteins alone
(gp160) and there are few results to indicate that this approach will work."

However, he went on to say that the position was different in the case of the
developments for a vaccine for HIV-2. Results of recent studies indicate that in animal
models the vaccine does provide good protection to a range of different strains of the
virus.

"Due to its limited ability to replicate, it is no doubt easier to protect against HIV-2
infected monkeys (and presumably also in humans) than it is to protect against HIV-1.
However, since HIV-2 can cause AIDS (even if less efficient than HIV-1), since it is
endemic in West Africa, since protection in monkeys occurred with an HIV -1 vaccinia
based vaccine, and since HIV-1 is now epidemic in West Africa I think it is reasonable
to argue for vaccine trials in West Africa now for 2 reasons:

     In the hope of reproducing the experimental primate results and achieving
     protection against HIV-2 (and so save lives).

     The possibility that in using HIV-1 reagents there may also be protection against
     HIV-1. (again saving lives)."

The contrast to this issue is the question of using these vaccines in populations where
HIV-1 is the predominant virus and has been shown to be far less effective in terms of
stimulating sufficient breadth of immune response to protect against the broad
spectrum of strains and variants of the virus (see article in this issue of HIV Herald).

Blocking HIV replication
It is necessary to ask if the blocking of HIV replication will be sufficient to halt the
progression to AIDS. It is not possible to give an absolute answer to this question at
this time. It is possible to say however that the continued presence of HIV as an
integrated part of the genetic structure of the CD4 cell etc., even if it is not expressing
the production of new HIV, will impair the function of the human immune system.

"However, the vast majority of clinical and laboratory studies indicate that HIV disease
progression correlates with HIV replication. Also, blocking HIV infection should reduce
the indirect disease causing effects of the virus or the chemicals (cytokines) that it
produces. Therefore it is reasonable to argue that one essential component of research
should include attempts to block HIV replication and do it as early as possible.

The biggest obstacles to effective therapies are toxicity and virus mutations with
resultant resistance to treatments. Most testing for new anti-HIV treatment today is
based on targeting enzymes of HIV (e.g. reverse transcriptase, protease, integrase etc.).
These programs now seem well established in the pharmaceutical industry and
ultimately I expect that an appropriate combination of some of them will make for
significant advances on the clinical effects of the virus."

Preventing HIV Mutation
Research efforts to try and overcome HIV mutations which escape from the effects of
treatment with our current range of antivirals include four main types of research.

1. Blocking HIV entry into cells
In theory one of the ways that this can be done is to use part of another virus which
binds to the same sites on the cell surface (i.e. the CD4) as HIV. Of course this virus
will need to be harmless.

Dr. Gallo went on to say, "We have recently reported that human herpesvirus 7 (HHV7)
utilises CD4 as its receptor for infection of CD4 cells. Consequently, it competes with
HIV for this receptor and in so doing inhibits infection of every strain of HIV we have
tested."

The objective therefore is to identify the structure and the effects of the HH7 envelope
structure that is responsible for this effect. If successful this may then provide a means
that a treatment and vaccine could be created that prevents infection from becoming
established in the human cells.

2. Targeting cellular factors
Because viruses require so called cellular factors for their replication, and since these
factors do not mutate easily as does the HIV, it seems reasonable to add cellular
factors  to the list of targets.

"The chief target of HIV infection is the 'resting' CD4 cell. But HIV is blocked after
entry into these cells in part due to insufficient amounts of deoxynucleotides in the cell
at that time (the building blocks of the DNA genetic chain)."

"As a result viral DNA synthesis and integration (into human DNA) is incomplete. These
pools of nucleotides are only increased when the T cell is activated or starts the
process of cell division. When this occurs it also allows the successful integration and
replication of HIV in that cell."

The increase in levels of nucleotides is in turn dependent on the activation of an
enzyme called ribonucleotide reductase. If this enzyme can be blocked the whole
process of viral DNA synthesis is inhibited, and in turn so is viral replication.

Hydroxyurea is a drug that is well understood (as it has been used in the clinic for over
30 years) and has few side effects. This agent is known to inhibit the enzyme
ribonucleotide reductase and so may have some potential in this area, particularly in
combination with current drugs  such as AZT or ddI .

Dr Gallo has suggested that  after appropriate pre-clinical evaluations, that a clinical trial
of combinations of these treatments should be initiated and easy to conduct.

3. Antisense
It has now been shown that a group of compounds called oligonucleotides are able to
inhibit the replication of HIV. The way this occurs is by a drug being designed
specifically to look like a small piece of the RNA of the virus, but in fact it carries an
opposite coding message.

This way the antisense drug attaches to the genetic code of the virus and so prevents
it from being read by the cell during the process of HIV replication. The end result is
that further HIV production is prevented. (for a full explanation see June 94 HIV Herald
p7).

The advantage of this approach is that it attaches to regions of the HIV genetic
structure which do not change because they are vital to the virus replication, and if
they mutate would render the virus inactive.

GEM 91 is the most advanced of these types of treatment and is now in phase I clinical
trials in the United States and in France. Results are not yet available.

The problems that Dr. Gallo foresees with this class of compounds are that they are
expensive, difficult to make, and there are problems in getting sufficient amounts into
the cell. "These problems do not appear insurmountable" he said.

4. Gene Therapy
The concept in gene therapy in AIDS is to place any gene that will inhibit HIV
replication into the genetic structure of the uninfected cell. Ideally this could be
achieved before cells are matured into CD4 type cells etc. This would probably mean
taking cells from the bone marrow, culturing them outside of that person and then
reinfusing them into the HIV positive person. In other words, the goal is to reconstitute
the immune system by protecting cells from infection.

Several approaches of this kind are now entering early phase clinical trials. They include
development of a gene that creates an antibody to the HIV-1 reverse transcriptase
enzyme. Another is the use of parts of the HIV-2 genetic structure that is known to
inhibit the HIV-1 replication cycle. Finally Dr. Wong-Staal is looking at a gene that will
create a "ribozyme" which if active will cut up the genetic material of the HIV.

Conclusion
Dr. Gallo then made the following overall conclusion" I have presented several new
areas where more crash* research programs are warranted. I am sure that many of you
are working with equivalently good or even better candidates for a crash program. We
need to develop mechanisms to assure that new and promising proposals obtain
support in a prompt and efficient manner in line with the urgency of the ongoing AIDS
crisis.

*Crash refers to rapid investigation into a concept or idea to see if it has an effect and
if it is worth developing into a larger research program.


BITS OF NEWS FROM YOKOHAMA

AZT  is not recommended in people
with CD4 counts above 500
Yet another report has stated that giving AZT (zidovudine) to people who have CD4
counts above 500 does not provide any survival benefit. It also does not prevent
progression of the illness with time when compared to people who start treatment with
the drug at levels below 500.

However, the drug does show an ability to slow the rate of loss of immune system cells
such as the CD4 (T Helper) cells, which are destroyed by the HIV, according to Dr.
Volberding from the University of California in San Francisco.

The report is from an extended analysis of the ACTG 019 trial. This is the longest trial
that has been following people with HIV who have used AZT either early or late in their
disease. It has enrolled 3200 people through 12 centres. Some 1637 people have been
followed since 1987, in terms of their illness progression when using AZT at a
particular point along the way. When enrolled the participant was randomised to one of
three groups:

     *Placebo
     *500 mg of AZT per day.
     *1500 mg of AZT per day

The question that the researchers wanted to answer was whether a person should
consider taking AZT above or below the magic 500 CD4 count. A previous report from
ACTG 019 showed that if treatment with AZT was started when the count fell below
500, there was a statistical benefit in terms of slowing the progress of the illness.

"We found in this new study the patients who took zidovudine (AZT) when their CD4
count was above 650 cells/mm3 there was a delay in the fall in CD4 count to  400 cells
by two and a half years when compared to those who took the treatment when their
CD4 counts had fallen below 500 cells/mm3" said Volberding. "But even with a slower
drop in CD4 count, there was no real difference in how long the patients lived, or how
fast their disease progressed from HIV infection to AIDS."

Again these results indicate that the effects of AZT are limited and they wear off. So
Volberding suggests that "The routine use of zidovudine in those who have CD4 counts
above 500 cells/mm3 is not indicated." AIDS Weekly August 15th 1994


Five year follow up study of ddI patients
with advanced HIV infection.
Patients with moderately advanced HIV infection had encouraging long-term survival
trends on ddI (didanosine) based therapy, a study by the US National Cancer Institute
(NCI) researchers has shown.

Patients who entered the trial with CD4 counts between 100 and 300 cells/mm3 had an
estimated four year survival of 80% according to Robert Yarochan, M.D. the study's
principal investigator.

"This was an uncontrolled study conducted in a referral hospital, and the observations
will have to be verified in larger randomised trials," Yarochan stressed. "However, the
results suggest that ddI can be tolerated over a long period of time, and that, even with
currently available therapies, fairly good survival rates are possible for people with
moderately advance immunosuppression."

The phase I (escalating dose and side effects) study of ddI began enrolment in July
1988 and ultimately included 72 patients. Yarochan reported on the course of these
patients through to July 1993 at the tenth International Conference on AIDS.

On entry, all patients had CD4 counts of less than 400 and the median count was only
50. 29 participants entered after an AIDS diagnosis. Beginning in April 1992, 16 of the
32 patients remaining in the study were switched from ddI alone to a combination of
ddI and AZT.

Median survival for the entire group of participants was 28 months. However, those
participants who entered with CD4 counts of 100-300 cells/mm3 had a calculated
survival of 80% after 4 years.

CD4 counts at entry was the most important prognostic indicator, with higher counts
associated with longer survival. CD4 counts above entry level at 3 and 12 months after
initiation of treatment were additional, independent indicators of prolonged survival. In
5 of 16 people who entered with CD4 counts between 100-300 cells/mm3 and who
remained in the trial, the counts were sustained above entry level for at least 3 years.

The major side effects seen in this trial, as in shorter term studies of ddI, were
pancreatic inflammation (pancreatitis) experienced in six people, and damage to nerves
of the feet (peripheral neuropathy) which affected 11 people and caused three to drop
out of the trial. The investigators did not see any previously unknown ddI toxicities,
despite the longer duration of the study.

"The patients reported here were participants in the first human trial with ddI, and this
represents the longest experience with the drug to date," Yarochan said. "The results
show that ddI can be tolerated over a period of time and can produce prolonged CD4
count rises in some people." AIDS Weekly August 15 1994

(Ed. Note: This is a very small study, and continuing uninterrupted treatment with  one
drug for periods of 3-4 years or more may need close monitoring and re evaluation if
there is any evidence to suggest that resistance is developing, or there is a general loss
of efficacy.)

ddI is more effective in combination with AZT.
The US National Cancer Institute (NCI) have shown results from a small trial that
indicates ddI is best used in simultaneous combination use with AZT to prevent
resistance developing to ddI.

In this trial only 1 in 26 patients developed resistant strains of HIV to ddI.  When ddI
was used alone, in monotherapy, 8 out of 9 patients developed resistant strains of HIV
to ddI in another NCI trial.

This particular trial compared the use of alternating azt/ddI therapy to simultaneous use
of AZT and ddI.  The results showed that both alternating and simultaneous use of AZT
and ddI reduced the development of resistant strains of HIV to ddI in the 26 patient
trial.  Patients in both groups of this trial had a significant reduction in viral load over a
2 year period.  However, there was a greater reduction of viral load in week 2 and
week 9 when AZT and ddI were used simultaneously as opposed to the alternating
group.

The presenter of this information has indicated that simultaneous combination use is
favoured at the beginning of antiviral therapy over alternating therapy and that more
work is required to clearly determine the duration of effectiveness of the two drugs
when used together.  Especially to find out what the clinical benefits may be.
AIDS Weekly, August 15, 1994


d4T (Stavudine) Results from a Large Clinic in the US.

Summary - in advanced HIV disease
     - increases CD4 counts in less than 1/3 of people
     - decreases in CD4 counts in greater than 2/3 of people
     - 50% of people had side effects from d4T

Dr Marcus Conant released some initial results in a retrospective look at 96 patients
using the parallel track program in the USA for access to d4T.  All patients had
advanced HIV disease and had previously used the other 3 antivirals (AZT, ddI and
ddC).  Of the 96 people using d4T, less than one third had CD4 cell count increases
while greater than two thirds had CD4 count deceases.  58.3% of people had some
type of side effect from the drug with 23 people withdrawing from the trial due to
these effects.  50% of people at some time experience peripheral neuropathy and
35.7% of people experienced insomnia, anxiety, and/or acute panic.

Even though these results may seem disappointing, it must be remembered that this
group of people had advanced HIV, and had already used 3 antivirals before using d4T.
To show benefit in 1/3 of this group of people having CD4 cell increases could be
considered to be expected, along with the side effects that have been shown.  We
already know that in advanced HIV, antivirals don't work as well as they could when
used in people with less advanced HIV, and that more side effects are experienced.
Source : Abstract, Xth International Conference 003B


Concerns about flu vaccination in HIV positive people
By Ian McKnight

At the recent international conference on HIV/AIDS held in Yokohama, a paper was
presented about the clinical effects of giving influenza vaccination to people who are
HIV positive.

The study had two groups, one being HIV positive and the other HIV negative. They
were then both given the same vaccination against the current strain of influenza. In
the weeks that followed, as the immune system reacted to the antigen, there were
corresponding and significant increase in the HIV activity in the positive group. This
was reflected in substantial increases (up to 250 times) in the viral load as measured by
PCR tests.

In addition it was noted that these viral load levels remained elevated for extended
periods of time. In some cases they had not returned to baseline levels at the six month
follow up point. The clinical ramifications of this effect are still unknown, however with
the growing consensus that the viral load is the key predictor of disease progression it
can be suggested that the use of flu vaccination could increase the risks of disease
progression, particularly if it is used at more advanced stages of HIV.

There are mixed concerns about these results, but one eminent Sydney research
clinician suggested that he would now think twice before suggesting such vaccination
be given to people at advanced stages of HIV.


RESULTS FROM AN AUSTRALIAN PILOT STUDY OF
ATEVIRIDINE (U-87201E) FOR TREATING
AIDS DEMENTIA COMPLEX
By Alan Strum

Summary -
     - ateviridine shows promise as a treatment
       for AIDS Dementia Complex

A pilot study of 10 people conducted by Dr Bruce Brew at the National Centre in HIV
Epidemiology and Clinical Research in Sydney has shown that 4 out of 5 people who
completed the study, treated with 600mg ateviridine 3 times a day, had improvements
in symptoms of their illness.

Ateviridine is a non nucleoside reverse transcriptase inhibitor.  It attaches to the reverse
transcriptase enzyme of HIV, and prevents HIV from changing into a form that can
infect cells that haven't yet been infected with HIV.

The study was made up of people who were showing early to moderate signs of AIDS
dementia or functions associated with thinking and moving around (stage 1 or stage 2).
By week 12, 2 people had improved from stage 2 to 0, and 2 from stage 1 to 0.5.  All
4 patients showed improvements by the 4th week of the 12 week study.  Only 1
person developed a rash during the study, which otherwise showed that the ateviridine
was well tolerated.

Dr Brew concluded that ateviridine was an effective treatment in this pilot study for
AIDS Dementia Complex (ADC) and called for further studies of ateviridine or similar
drugs to be considered for treating ADC.
Source : Abstract, X international Conference, 232B

Results from studies of long term non-progressors.
By Alan Strum

Non Progressors -
     - CD4 cells are not resistant to infection
     - have a very strong antibody defence against HIV
     - have a very strong CD8 response to HIV infected cells
     - appear to have a changed and less effective HIV strain
     - HIV is still generally infectious

David Ho presented information at the Xth International Conference on long term
survivors of HIV who had HIV for at least 12 years with no symptoms and normal
stable CD4 cell counts.  Out of 11 people studied it was not possible to find infectious
virus in the plasma (blood fluid).  Viral RNA, the amount of viral activity or replication,
was detectable at levels that were well below that found in patients with disease
progression.  One subject showed viral replication from immune cells.  Two subjects
showed replicating virus only after many attempts had been made to grow the virus,
and one subject showed replicating virus only after their CD8 (virus inhibiting/killing
cells) had been removed from the cell cultures.  Whole active virus was never recovered
from the other subjects.  From 2 of the subjects where HIV had been isolated, the HIV
itself replicated at a very low rate compared to normal virus.  This has suggested the
possibility that these HIV samples had somehow changed or mutated into a form that
may be a less dangerous or less virulent virus than HIV found in other people with
disease progression.

The patients that were tested showed a better neutralising antibody responses to HIV
than patients with disease progression.

When active virus was added to cell cultures containing immune cells from "normal"
donors and non progressors, the viral antigen (parts of the virus) levels in the normal
donor immune cells reached very high levels over a 2 week period, where as the
antigen levels in the non-progressor cell cultures had a small initial peak followed by a
decline of antigen levels.  To determine whether the CD4 immune cells had an inherent
resistance to infection it was discovered that viral antigen levels increased only when
the CD8 cells were removed.  The level of antigen production was again reduced by
adding the CD8 cells back to the cell culture, thus indicating that the protection was
under the control of the CD8 cells and not from the CD4 cell being resistant to
infection.

In a presentation by Fauci on long term non progressors, Fauci added the Lymph node
structure (where immune cells gather) remains well preserved and that the amount of
virus remains low but is generally still infectious and can replicate.
Source : David Ho, transcript from the Xth International Conference
AIDS Weekly, August 15,1994


Results from RGP160 European Trial
By Alan Strum

Immuno rpg160 is a purified protein of the outer coat of HIV-1 being used in people
with HIV in a 16 centre European trial.  This trial has been split into 2 groups of people
with counts above 500 CD4 cells and counts between 200 - 500 CD4 cells.  An
immune response was observed in half of the trial group with CD4 cells above 500, and
in one third of the trial group with CD4 cells between 200 - 500.  This vaccine
appeared to cause an immune system memory response as was shown by
lymphoproliferation responses (quick increases in immune cell numbers when exposed
to the vaccine again).  The findings from this trial will help to understand at what stage
of HIV disease should therapeutic vaccines be used.  The vaccinations themselves did
not show any significant side effects.  During the 12 month follow up period of these
groups of people, blood chemistry and cell counts have remained unchanged.  The
effect of this study on viral load is currently being investigated.  The volunteers are
being closely monitored for any changes in health and immune activity.
Source : AIDS Weekly, Aug 15, 1994


VACCINES - WHERE ARE WE NOW?
By Alan Strum

Summary -
     - current gp120 & 160 vaccines don't give protection against primary HIV
     isolates.
     - gp41 appears to have a common site among 4 HIV strains.

Over the past year we have begun to understand where we are at with the first
generation of candidate vaccines.  The seroconversion of 5 people in the USA who had
participated in the candidate trials has indicated to us that the vaccines that were
developed from laboratory strains of HIV do not show sufficient protection against HIV
found in humans.  This has been confirmed in both the gp120 and the gp160 vaccines
in laboratory tests where the antibodies were taken from volunteers, who had been
vaccinated, and were tested against laboratory strains of HIV and freshly isolated HIV
from people.  In both types of vaccine candidates, the antibodies were able to react
with (neutralise) the laboratory strains but were not capable of significant responses to
the HIV strains taken from people (primary isolates).

This has lead to a theory that perhaps the outer coat of HIV is not just a dull solid
chemical structure, but is a complex structure that reacts with itself and the receptors
and membranes of the cells that it attaches to.  Resulting in the chemical structures of
the outside coat of HIV bending over to expose different sites of the coat to which the
bodies immune system can recognise and produce more effective antibodies.  Perhaps
it is the recognition of these "flexible" exposed sites that give long term nonprogressors
such good neutralising antibodies against a broad range of HIV isolates.

It is also necessary to determine if vaccines developed against one strain of HIV would
work against other strains of HIV around the world.  To answer this, a recent study in
Thailand looked at the antibodies taken from 20 people with HIV-1 to see how their
antibodies would interact or neutralise 4 different HIV strains from the USA, Rwanda,
Thailand and Romania.  They found that the antibodies reacted strongly against the
Thai gp120, moderately against the Rwandan and Romanian gp120 and only weakly
against the US gp120.  However, antibodies reacted equally well against the gp41 from
all 4 HIV strains.  The researchers have found that this particular antibody attaches to a
specific area on the gp41 and is able to neutralise the HIV.

This has left the scientists questioning whether the vaccines in trials now will be
effective against HIV.  It appears that we are still only just at the beginning of
understanding how to combat HIV, but at least the scientists are slowly learning along
the way.  Perhaps next year will see further development of the next generation of
vaccines for both therapeutic and preventative treatment eg using non dangerous
viruses or bacteria to carry the HIV vaccines etc.
Source : D. Bolognesi transcript from the X International Conference
AIDS Weekly, August 22, 1994



NEWS

Viral load measurement becoming an
important surrogate marker.
By Ian McKnight-Smith

One of the positive messages that is now emerging from many of the scientific reports
including those that came out of the recent Yokohama conference on HIV and AIDS is
that the direct measurement of the levels of activity of the virus in the human body
may be a better indicator of the changes in health status, or progression to later stages
of the illness. This measure of the amount of virus in the body is called viral load or
viral burden. Studies have also shown that as the level of viral burden goes up then the
risks of disease progression or sickness appear to go up as well.

In addition to being seen as an important marker of disease progression, it is also being
considered as an important measure of how effective an antiretroviral treatment is
working. When the antiviral therapy is effective there should be a corresponding fall in
the levels of virus in the blood. This would be seen as a fall in the measurements of
viral load. Further more, if the viral load is then seen to increase after a period of time
on treatment this may  be a good indicator that the drug is no longer working, or there
is a development of resistance.

There are now a number of tests that are being used to measure the viral load. The
most accurate are measures of the levels of viral RNA or branched viral DNA (bDNA).
However we will not consider bDNA at this point as it is very expensive, currently being
in the order of thousands of dollars per test. Viral RNA tests, while still expensive, is
more feasible with estimates suggesting that the commercial version of this test will be
in the order of $100+ per test. Clearly as the demand and use of these tests increase
we can expect significant drops in the costs of these tests.

RNA stands for ribonucleic acid and is the substance that carries all of the genetic
information of the virus. Viral RNA can be measured by a specific test called a PCR.
These letters stand for Polymerase Chain Reaction, and this is a test to detect and
amplify the presence of fragments of the RNA from HIV that are in the blood stream. It
is highly sensitive and can detect very small changes in viral activity, even in the earlier
stages of HIV infection.

One of the early problems that has been associated with PCR tests is that it is too
sensitive. As a result, it has required very specialised operators and laboratories to
conduct these tests so that they could provide accurate and reproducible results. In
turn this has meant that the tests are expensive and have usually only been carried out
as part of a specialised clinical research study.

However, a number of companies including Roche and Genelabs are developing a PCR
test that they hope will overcome the current restrictions of specialised use. It is hoped
that in the near future it may be added to the battery of tests used when routinely
monitoring for changes in HIV activity. At this point in time we are still a little way off,
in terms of having a "test kit" that is easy, reliable and economical to use on a routine
basis.

Recent reports also suggest that certain tests may be more useful at different times in
the course of HIV infection. It is suggested that PCR testing may be more effective in
the earlier stages of HIV, while using branched chain DNA may be more effective in the
later stages. However more information is needed to clarify this further.

How may measurement of viral load be useful?
There are a number of points in time where tests of viral load could be useful as
predictor of changes in the course of HIV disease and also as a useful marker of
antiviral treatment. Some examples include:

-A person with no symptoms of HIV illness, may at some point show an increase in
viral RNA PCR levels. Such an increase would indicate that there is an increase in HIV
load in the blood stream. If this change in viral load is sustained or increases further
over a period of time, researchers now suggests that there is an increased risk of
disease progression. Logically therefore this may be a point in time where that person
may consider starting antiretroviral treatment.

Reports of studies that were presented in Yokohama support this approach. In analysis
of participants in trials such as ACTG 116a they were able show that there is a
correlation between the viral load and progression of HIV. Further it would appear that
viral load is far more accurate a predictor of health changes than the surrogate markers
like CD4 count or P24. ACTG 229 is a study that is looking at the use of two and three
antiviral treatment regimens (AZT, ddC and saquinavir which is a proteinase inhibitor) in
people with CD4 counts less than 300. In their measurements of viral load (by
PBMC..Peripheral blood mononuclear cell test) they were able to show that there were
significant falls in virus levels when treated with two or three drugs, and the three drug
combination produced significantly greater reductions than the two drug arms of the
study.

Douglas Mayers reported that RNA measurements are predictors of clinical outcome
among people receiving AZT treatment. The study looked at 100 HIV positive people
and serum HIV from the cohort was tested for sensitivity to AZT that is they tested for
the codon 215 mutation which is associated with high level resistant strains of HIV,
syncytium inducing phenotype (SI) and viral burden via plasma RNA was measured by
PCR.

CD4 counts of less than 200, high viral resistance to AZT on entry into the study, and
high viral burden were all directly related to an increased risk of dying. People with low
viral burden (less than 1,000 copies of RNA per millilitre) had little risk of death, while
those with the high viral load readings (greater than 10,000 copies per millilitre) had a
40% risk of death within one year.

-It may be an indicator of when an antiretoviral treatment is losing its ability to control
HIV replication (i.e. efficacy). A sustained increase in PCR test values would indicate an
increase in the amount of virus in the blood stream. This in turn would indicate that the
virus is replicating at an increased rate, and/or it is no longer being contained, e.g. in
the cells of lymphoid tissue. This in part may be due to the emergence of resistant virus
to the treatment(s) being taken.

In such circumstances decisions may need to be made about changing the treatments
program. Some of the options could then include, stopping the drug currently being
taken, swapping to another form of treatment, or the adding in of another antiretroviral
in an attempt to suppress the resistance.

-In a clinical trial setting, where new antiviral treatments are being tested, there is a
potential for measurements of the viral load to quickly show if the treatment is
effective. A substantial and sustained fall in the viral load would indicate that the
treatment is  effective in controlling the virus. The smaller the reduction in viral burden
the weaker the product. It is also true that a measure of the time that the viral load
remains at a lower level is a clear indicator of the treatments ability to prevent the
emergence of resistance.

As mentioned previously this will also have particular relevance when studies are
conducted with 2, 3 and 4 drug combinations to see if a greater viral load reduction can
be achieved. Certainly early studies like ACTG 229 would suggest it can.

In addition, as the research on multiple antiviral treatments become more widespread
due to the increasing number of new antiretroviral agents and an increasing focus on
combination therapies using up to four different drugs, it will become practically
impossible to  complete very large clinical studies that rely on hard clinical endpoints
such as the development of a new AIDS-defining illness or death. Further, the answers
would take a long time to be forthcoming since they would have to have a very long
recruitment and follow up time to reach statistical significance. Therefore, the
establishment of true surrogate markers of therapeutic efficacy has become perhaps the
highest priority in the AIDS clinical trial. Measurement of viral load decrease and the
time before this load begins to increase once more are important measures of antiviral
effect that could quickly provide answers to research questions .

-In recent months studies have found that there are real possibilities of reducing
transmission rates from mother to neonates particularly if there is a lower viral load at
the time of delivery. A recent study has reported that there was a 2/3rds reduction in
transmission from mother to baby if the mother is treated with 500mg of AZT after the
14th week of pregnancy.

It is logical to suggest that the lowered transmission may be due to a significantly
lowered viral burden. In other words significantly lower levels of virus in the blood
stream that could be transmitted to the foetus.

-Similarly a Swiss group have reported in a small study that a group of people who
received AZT during the time of seroconversion were reported to have a smaller fall in
CD4 counts during this period and were better off (CD4 counts) after one year of follow
up as compared to a group that received no treatment. Again this suggests that the use
of antiviral treatment has reduced viral burden during this phase and this in turn has
slowed the progress of the illness overall.

Such studies would suggest that there are particular times when intervention to reduce
the levels of virus may have a beneficial effect in terms of slowing progression of HIV.
This is closely allied with the notion that the introduction of antiretroviral treatment
would be initiated only at times when there is a rise or break through in the viral
replication as seen by changes in viral load measurements.

ASPIRIN MAY BE A TREATMENT FOR HIV
By Alan Strum

An article in a British news paper, the Telegraph Weekly, has reported findings from
Yale University that aspirin may be an effective treatment to slow down HIV
replication.  It has been suggested that aspirin may be capable of inhibiting a protein
that is responsible for reading the genetic code of HIV.  These results are currently only
at a very preliminary stage.  The National Treatments Project will investigate this further
as the information becomes available.
Source : Croll's Press clips


Rifabutin approved for treatment
and prophylaxis against MAC
By Ian McKnight-Smith

The Australian Drug Evaluation Committee has approved the licensing of rifabutin
(Mycobutin) for both the treatment of MAC (mycobacterium avium complex) and the
prevention of the onset of the illness in people who have a CD4 count below 200.

We have however, been advised that the negotiations on getting the product
reimbursed either through a section 100 or by a direct listing on the PBS have been
deferred pending an expert review. This means that for the moment unless the hospital
pharmacy is prepared to pick up the bill the person being prescribed this drug will have
to pay for it. Unfortunately this is not cheap with a price tag of $147.00 as the cost
price to pharmacy for a pack of 30, capsules. The dose of each capsule being 150 mg
of rifabutin.

The recommended dose for prophylaxis is 300 mg per day which means that 2
capsules will need to be taken daily. This therefore translates into a cost of $294.00
per month, plus the dispensing fee.

For treatment of MAC the dose is higher with a recommended dose of between 450
and 600 mg per day. Again this translates into a monthly cost of between $441.00 and
$588.00 per month plus the dispensing fee.

A number of studies have demonstrated this treatment's effectiveness in prevention of
MAC, but much of this work has been conducted in people who have higher CD4
counts (starting at CD4 count of 200). Since the risk of developing MAC are low until
reaching CD4 counts of around the 100 mark and below, the company (Pharmacia)
have indicated that this is a more realistic point where prophylaxis would be
considered. Where rifabutin has been used the effects have been dramatic, with a
significant fall in the incidence of MAC in the HIV positive population.

The main claim of benefit of using rifabutin is that it has a longer half life and is able to
better penetrate the cells where it needs to act. Thus making it more effective in
removing the mycobacterium and hence reducing the risk of MAC disease from
developing.

The side effects are few and in many cases they have been no more than the group
taking placebo. The kinds of things that need to be looked for include gastric
disturbances (vomiting, nausea, diarrhoea) and in these cases the effects may be
reduced by taking it with food. Other side effects are unspecified with some people
reporting "neurological disturbances". It is true to say however, that on balance it
appears to have a better side effect profile when compared to other treatments used for
MAC.

The main concern by some clinicians is the development of resistant strains of the
mycobacterium when using the drug as a prophylaxis. To date research has not shown
this to be a problem, but the treatment has still only been used in a relatively small
number of people.

The NTP is currently preparing a fact sheet on rifabutin and we will include this in a
future issue of the HIV Herald.

CLINICAL TRIAL NEWS

Protease, AZT and ddC combination trial results
By Ian McKnight-Smith

The three drug combination of AZT, ddC and Roche's protease saquinavir (Ro 31-8959)
may be more effective than two-drug combinations, according to a U.S. study.

302 people with CD4 counts between 300 and 50 were enrolled in the trial ACTG 229.
All of the participants had already taken AZT for at least 4 months prior to starting in
this study. They were then randomly assigned to one of three treatment arms as listed
below:

     *AZT + ddC + Saquinavir
     *AZT +ddC
     *AZT + Saquinavir

The clinical effectiveness of the two and three treatment combinations remains to be
determined in future studies. The trial was not designed to detect differences in disease
progression or to predict survival benefits.

In each group, participants' CD4 counts rose during the first 8 weeks, but then
gradually declined. However, people taking all three drugs has the greatest increases in
CD4 count, and after 6 months over two thirds of this group still had counts that were
higher than the baseline level when they entered the study.

By contrast, CD4 count increases in the other two groups were smaller and less long
lasting.

The researchers also measured the effects of the treatments on viral load - the amount
of HIV detectable in their blood. Again, the three-drug combination produces a
significantly greater reduction in viral load than the other two drug combinations.

Dr .Janet Derbyshire, head of the Medical Research Council's HIV Clinical Trials Centre
in England described the findings as "promising, but not as exciting as we might have
hoped for. But participants had taken quite a lot of AZT , and you might have seen a
greater difference in an AZT-naive population. We still need to look at whether these
surrogate marker changes translate into a clinical benefit."

Clearly more work needs to be done particularly in terms of the effects of these
treatments on clinical progression, but also in looking at the proteases in combination
with other antiviral treatments.

Further research is now being conducted that is testing a number of different protease
inhibitors. The grapevine would suggest that indeed the Roche product (saquinavir) may
not be the best product. The problems with this drug appear to be that it has very low
absorption into the blood stream. Further work is being planned using higher doses but
then the problem may be that it will be too expensive when compared to other
products. Some of the other proteases in trial in Australia appear to be giving better
responses and maybe this is due to more of the active agent getting to the sites where
it is needed.


Human Growth Hormone trialled
against HIV wasting
By Ian McKnight-Smith,
adapted from an article by John James at AIDS Treatment News.

A multicentre placebo controlled study in 187 people with HIV related wasting has
shown positive results. This could be the first time that there has been solid evidence
to suggest that something can be done to reverse wasting and hence avoid what is a
life threatening condition.

The report by Dr. Schambelan of San Francisco General Hospital stated that this was
the first time that there was a treatment that consistently restored lean body mass in
people with wasting syndrome.

Participants in this study had had at least a 10% reduction in their pre illness body
weight, or they were reported as being less than 90% of their ideal weight, and it
turned out that as a group they had an average of 14% loss in body weight.

A further entry requirement was that the person was able to eat, and that they could
consume at least 75% of their normal daily calorific requirement. Participants were also
encouraged to exercise if possible, however this was not a requirement to enter the
trial.

In the study 90 people received growth hormone at a dose of 0.1 mg per kilogram or at
an average dose of 6 mg per day. This was given as a daily injection under the skin. A
further 88 people received a placebo injection in the same way. The treatment was
continued for a period of 3 months. After that time all of the participants were given
open label drug for up to two years. During this time they are to be followed and data
about long term use and side effects is to be collected.

Results:
The group that were given the placebo initially showed an average increase of 0.45kg
(1 pound), but most lost this gain during the three months of treatment. Those who
were given the growth hormone gained an average of 1.33 kg , but what is more
important, this increase was sustained over the full three month period of therapy. In
some cases the increases were more dramatic, with increases of nearly 9 kg. which
was also sustained after the trial was completed. In others the increases in body weight
have continued to slowly increase as treatment has continued after the formal part of
the trial  was finished.

The trial was also able to show increases in lean body mass as well as absolute body
weight increases. The average increase in body mass was nearly 2 kg for the treated
group, so this means that the loss had included losses in fat, muscle mass and also in
bone density as well.

There were five deaths during the study, three were receiving the growth hormone and
two the placebo. In all cases they were due to infections in people with very low CD4
counts and were not thought to be related to the use of the growth hormone.


Side effects
The main side effect that has been reported with the use of human growth hormones is
the development of antibodies to the hormone itself. It is then a possible risk that there
may be an allergic or anaphylactic shock to the substance when it is injected on an
ongoing basis.

The experience in using it in growth deficient children is that the phenomenon of
antibody production only occurs in some people (2-15% after 6 months treatment) and
that this has not then resulted in immune system reactions.

One suggestion has been made that if the use of these substances does activate the
immune system, this in turn may activate HIV replication. Certainly further investigation
of any changes to viral burden are needed.

The only other side effects reported in HIV negative people usually occur at the higher
end of the doses used and include: headache, pain at the site of injection, loss of fat
tissue.

Availability
Human growth hormone products are available in Australia and these are listed in the
table below. As would be expected they are licensed for use in children who have
growth deficiencies and not for HIV wasting syndrome.

So to access this drug you would need to have a doctor write a private script and this
would be a reasonably expensive exercise. However with this report there is a stronger
case for use in some people with HIV and AIDS, and therefore access for
compassionate use, or a commencement of a broad based clinical trial should be
considered, particularly as further trials are being conducted in the US in an effort to
obtain FDA approval for HIV wasting.

Growth Hormones available in Australia

     Generic name: Somatropin
Brand Name               Manufacturer

Genotropin               Pharmacia
Saizen              Serono
Norditropin              Novo Nordisk
Humatrope           Eli Lilly

     Generic name: Somatrem
Somatonorm               Pharmacia

Although administration is by daily subcutaneous injection, this can be easily achieved
with the equipment that has been developed by each of the manufacturers. Since this
material has to be self administered for the most part by children, the injecting devices
are simple to use, provide a measured dose each time, with minimum of trauma to the
person involved. This of course makes it a real possibility for people with HIV.



NUTRITION

ZINC SUPPLEMENTATION MAY DECREASE
THE NUMBER OF OPPORTUNISTIC ILLNESSES
By Alan Strum

Zinc deficiency is often associated with immune abnormalities and an increased
vulnerability for infectious diseases.  In approximately 30% of people with HIV,
zinc deficiency can become apparent at stage III (symptoms without an AIDS
defining illness) and even more so at stage IV (AIDS).

A research group in Italy gave 200mg/day of zinc for 30 days to 18 people
taking AZT with stage III HIV and 12 people with stage IV illness.  Results were
compared to a control group not taking zinc supplementation, 19 at stage III and
11 at stage IV.  They found that people taking zinc had increases in CD4 cell
counts.  After 24 months following entry into the study, the number of
opportunistic illnesses occurring in the group that had zinc supplementation was
reduced - stage IV had 9 infections vs 26 infections in the control group, and
stage III had 1 infection vs 13 in the control group.  The opportunistic illnesses
that were reduced in the zinc group were PCP (pneumocystis carinii pneumonia),
cryptococcosis, salmonella, and tuberculosis.  The number of times both groups
had cytomegalovirus (CMV) and oesophageal candidiasis remained unchanged.
Source  : AIDS Weekly, August 15, 1994

[Editors note] This information may look impressive, but closer examination of
the information leaves a lot of questions to be asked such as ; - what were the
actual numbers of people who experienced opportunistic illnesses?  Were the
illnesses only in a few people, or were they evenly distributed among the people
in this study?  It is also important to remember that zinc supplementation is
considered by some to be controversial.  An example of this is the Beach study
that showed a connection between increased zinc intake and a direct increase in
progression of HIV disease.