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February 7, 2010)
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From http://www.guardian.co.uk
Feb 5,
2010
Unhappy fact about Aids in
But in December a big
trial in four African countries of a promising microbicide collapsed. The
wonderful Professor Gita Ramjee, who has run five different big microbicide
trials at her centre in
So I was quite surprised
to hear that the Wellcome Trust has just given £2.7 million to the Mintaka
Foundation for medical research, a philanthropic outfit in Geneva, to enable a
couple of British professors to get a novel microbicide product they have
dreamed up "onto the doorstep of clinical trials" as one of them,
Oliver Hartley, told me on the phone.
What makes them think they
can do it when every attempt so far has gone pear-shaped? Hartley says they are
better prepared.
"The substances
tested before were put into the clinic rather quickly because the situation is
so desperate, without having been fully scientifically validated," he said.
"Unlike those other
substances our material is very, very potent indeed and can fully protect female
macaque monkeys. We're in much, much better shape than anything before."
Their microbicide is a
protein. Most proteins are fragile and have to be refrigerated. Theirs can be
boiled. They can make it using brewer's yeast, so it's low tech and cheap for
African countries, they say.
There are some more big
microbicide trials underway, using an Aids drug called tenofovir. Scientists are
hopeful - but using an antiretroviral even in gel form on a regular basis could
cause side-effects and may lead to resistance. Maybe Mintaka is on to something.
The Wellcome Trust seems to think it's worth a shot.
Meanwhile the Lancet today
has a go at obstetricians who promote caesarean sections. A quarter of
caesareans in
Published Sun, Feb 07,
2010
The mice in J. Victor
Garcia-Martinez's lab at UNC-Chapel Hill foretell a major new breakthrough in
the fight against AIDS.
Engineered to have human
immune systems, healthy rodents have repeatedly been exposed to the virus that
causes AIDS, but nearly all have warded off infection. Their immunity comes from
a daily, preventive dose of a common anti-retroviral drug.
What that means, if the
results bear out in human trials under way, is that a pill a day may keep
infection away.
"It looks to be one
of the most promising prevention [approaches], but like everything in HIV,
nothing is simple," said Dr. Timothy D. Mastro, vice president of health
and developmental sciences for Family Health International, a research group
that is testing the daily pill in human trials.
Hailed as a potentially
momentous development, a prevention pill could also carry significant public
health risks. (HIV infects an estimated 2.5million new people a year worldwide.)
Among the biggest fears is
that a daily prevention pill, used incorrectly, could fuel a resistant strain of
the virus, much like rampant antibiotic use has rendered many front-line weapons
powerless against common bacterial infections.
And taken daily like a
birth control pill, which guards against pregnancy but does nothing to protect
women from sexually transmitted diseases, an HIV pill could also spark epidemics
of syphilis, hepatitisC, herpes and other diseases, if people quit using condoms
during risky sexual encounters.
That's a likely if.
Only about 40 percent of
men and women in the
Yet such perils do not
dampen excitement about the prospect of a prevention pill, particularly as
vaccines and cures remain distant ambitions, despite billions of dollars spent
on research.
"It's a humongous
leap forward," said John Paul Womble, an AIDS activist and interim director
of the Alliance of AIDS Services -
'The approach is terrific'
Much depends on results
from the human trials. At least nine trials involving more than 20,000 people
are in various stages worldwide. A small
Mastro, at Family Health
International in
Such results could be
available within two years, Mastro said.
But tantalizing insights
have emerged from the mouse study, reported in January by Garcia's lab at UNC-CH.
Using humanized mice,
Garcia's team exposed them to HIV. For all routes of infection - both sexual and
intravenous - the daily prevention dose protected the animals from contracting
HIV. Even with intravenous exposure, which is the virus's most efficient path
into the body, infection was stymied in all but one mouse.
"That is
amazing," Garcia said. "You cannot give the virus a better opportunity
to infect than intravenous exposure. The fact that the drugs worked - the
approach is terrific."
The strategy is not
entirely new.
For years, doctors have
nearly eliminated HIV transmissions to infants by giving a regimen of
anti-retroviral drugs to infected mothers before childbirth, and then to the
babies immediately after. Nurses and other health workers have also been given a
short round of the drugs to thwart infections after accidentally pricking
themselves with HIV-contaminated needles.
But the key to the current
approach is offering daily pills to healthy people before any known exposures
have occurred - so-called pre-exposure prophylaxis.
Current PreEP trials are
testing the drug Truvada, an anti-retroviral therapy in the arsenal doctors use
to treat HIV-positive patients.
Among the biggest chal
lenges is making sure people take the pills every day. As any woman who uses
birth control pills can attest, there are inevitable slip-ups.
What worries researchers
is that on-again, off-again use enables the wily HIV to develop resistance to
drug therapies. And poor compliance could be a significant issue, especially in
the
"It is something that
definitely can't be ignored and must be addressed head-on," said Paul W.
Denton, a member of Garcia's research team. "Adherence is going to be the
key to preventing resistance. But you can have individuals who will not follow
instructions. We put seats belts in cars and not every one chooses to wear
them."
Still, the risk that HIV
could develop resistance is small, other researchers said, and does not outweigh
the potential benefits of a prevention pill. Dr. Myron Cohen, an infectious
disease specialist who leads UNC-CH's HIV research efforts as director of the
Institute for Global Health and Infectious Diseases, said the drug being used as
the prevention pill holds up well against the virus's mutations.
"Resistance is
something to be monitored and concerned about, it's not a reason to quit,"
Cohen said.
Keeping condoms
Acknowledging the risks,
health leaders are working to craft an approach that would assure the best
compliance should a prevention pill roll out.
Mastro said Family Health
International is involved in some of those efforts.
"If and when we prove
that pre-exposure is safe and effective, we will have a real challenge to make
sure the prevention message is communicated," Mastro said.
One approach is to stress
the continuing need to use condoms in addition to taking the pill. That's a
tough sell.
In the gay community,
where the message to use a condom has been a drumbeat for the more than 25 years
that HIV has been identified, the temptation to pop a pill and forgo other
protective measures could overwhelm better judgment.
"'Condoms are
important for everybody but me' - that's the mind-set, and it landed me where I
am today," said Womble, who is HIV positive and now works as a community
activist with the AIDS alliance.
Womble said instead of
using condoms, many gay men now choose to segregate themselves into HIV positive
or negative groups, essentially limiting their sexual encounters to people who
share their HIV status.
And that has its own
pitfalls - among them a resurgence of other sexually transmitted diseases.
In recent years,
Public health leaders fear
an HIV prevention pill could exacerbate that trend.
"It's good news,
certainly, and if the human trials look good, it's an immense cause to
celebrate," said Jacquelyn Clymore, head of the state's HIV/STD prevention
branch. "But HIV is just one of the things that you can transmit and catch.
A pill is not going to change the fact that everyone still needs to know their
HIV and STD status, and we have to make careful and responsible decisions about
who we're doing what with in order to protect our health."
Building a triumph
Despite the inherent
hazards, Clymore and others said a prevention pill could usher in an entirely
new era in the fight against HIV - and that would be a welcome victory.
Since HIV was identified
in the 1980s, the
Finding a vaccine,
especially, has been frustrating. Scientists five years ago regrouped after yet
another vaccine candidate failed, forming an international consortium centered
at
Those efforts are no less
important, even if the prevention pill proves safe and effective, said Cohen,
the UNC-CH researcher, who is also one of the leaders of the vaccine consortium.
"Every case where we
prevent infection is critical," he said. "But to have the entire
species take a pre-exposure prophylactic is unreasonable. We haven't worked out
the details of this intervention - who will be given the pill and to what
benefit. And you still have all the other STDs, unwanted pregnancies and other
things."
Costs are also a factor. A
regimen of Truvada runs upward from $850 a month when used as an HIV treatment,
and it's unclear whether the costs would come down for a daily prevention pill.
Cohen said additional studies may prove that daily use isn't necessary, or that
a topical gel could serve as an option.
Yet in the absence of a
vaccine or cure, a prevention pill is progress - if also an additional
challenge.
"The fact of the
matter is, anything that will help reduce the spread of any STD is to be
commended and embraced without exception," said Tom Intiso, an AIDS
activist with the alliance. "The problem is ... we have failed across the
board, as public health professionals, to do a good enough job in the community
to prevent HIV and STDs."
Tobacco may become an
unlikely ally in the fight against HIV in developing countries
Louise Tickle
The Guardian, Tuesday 2
February 2010
|
| Professor
Julian Ma with his GM tobacco plants at |
Fighting HIV with tobacco
doesn't sound like something a doctor would normally recommend. Condoms and/or
abstinence are the two standardly recommended methods of avoiding infection, but
both clearly have inherent drawbacks.
"Condoms work well,
but they also prevent fertility, so if you want to have children and you're part
of a community where there's high risk of HIV infection, you've got a
problem," points out Professor Julian Ma, of
With no cure or vaccine
for HIV yet available, Ma and his collaborator, Professor Rainer Fischer, are
co-ordinating a team of researchers across 39 European institutes who are now
focused on neutralising the virus before it can cause infection – and this is
where a soupy green sludge of pulverised tobacco leaves might provide an answer.
The idea of using plants
to create antibodies to disease was initially mooted in the late 1980s, says Ma.
"You had flights of
fancy where people were talking about growing fruit that would contain vaccines,
the idea being that you could give a banana to a child and they'd be immunised
against a particular disease," he explains.
"It's very attractive
at first glance, but people have pulled back from that because dose control is
very important, and also control of administration. The concept, however, of
growing plants containing useful substances – which you could process, extract
and freeze-dry, then have administered by a medical professional – still
remains."
As Ma points out, the
ravages of infectious diseases are borne most heavily by poor people in
developing countries who can't afford to buy medicines, and where safe and
reliable methods of distribution can be hard to ensure.
His aim, therefore, is to
come up with an HIV neutralising agent that can be made cheaply, on a large
scale, and where production can be easily carried out in developing countries
themselves.
The delivery method for
the antibody he's intending to use is a topical microbicide – put simply, a
gel, like a spermicide, that would be inserted vaginally or rectally, and so
would be under the complete control of women. It would neutralise the HIV virus,
but would have no effect on sperm, so fertility wouldn't be affected.
Interestingly, antibodies
that neutralise the HIV virus have already been identified and can be made to
order. The problem is that creating such highly virus-specific antibodies –
monoclonal antibodies – is expensive. The anti-cancer drug Herceptin, for
instance, uses monoclonal antibodies and its prohibitive cost has made it a
controversial drug for prescription even in some developed countries.
Ma, moreover, says that
because viruses mutate, any microbicide would ideally be a cocktail of two or
three antibodies. This makes the medicine twice or three times more expensive.
Enter the tobacco plant.
Plants can grow proteins – which is what antibodies are – and if they're
genetically modified, they can grow specific proteins that scientists know will
act on the HIV virus (though diseases such as rabies could also be targeted).
"Common sense tells
you plants are going to be cheaper," says Ma. "You could eventually
grow them in fields on a large scale, but there are environmental issues that
mean this is unlikely to be acceptable in the short term. Pollen from our
tobacco plants might get released, or you could get animals eating them."
The solution currently is
to grow the tobacco plants in glasshouses. This is being done in compost in
The most advanced part of
the project to date is the compost-grown tobacco. But soil as a growing medium
is hard to control in the way that pharmaceutical regulators need – in
different parts of the world it would be made up of different components, for
instance.
On the other hand, if
antibodies from soil-grown tobacco are proved to be safe and effective, it may
be that the issues of standardised soil composition can be overcome, enabling
developing countries to grow the raw materials for an effective HIV microbicide
easily and cheaply.
Once the plant is mature,
the leaves are harvested, ground up and purified to extract the antibody. This
is currently being done in the Fraunhofer Institute for Molecular Biology and
Applied Ecology in
Approval for the trial
production process has just been granted in
Getting the pharmaceutical
industry to take the research seriously has also proved tricky, says Ma. At this
stage in a drugs research project, it would be normal to expect some serious
industrial investment, but nobody's been willing to cough up. "There's been
some disbelief that plants would be viable," he explains. "Plus, it
would be a push to make pharmaceutical companies switch their production
methods, because they've invested so much in existing systems."
Ma also points out that
pharmaceutical companies' priorities are not to produce drugs for
developing-world problems, because, presumably, there isn't any money in it. The
final nail in his hopes of investment at this stage has been corporate wariness
around genetically modified products.
He's optimistic, however,
that "once through this trial, if we can demonstrate that plants are
acceptable as a clinical product and we show that it's a scaleable method, I do
think many will come in."
It's likely to take about
five or six years to reach that stage. In the long term, Ma would like to see
pharmaceutical production as an industry that could provide an alternative
income for farmers both in
"It couldn't be a
field of food and a field of pharma sitting side by side," he says.
"It would need to have a dedicated farmer with expertise."
The debate raging around
GM food hasn't yet been comprehensively won by either side: now that GM
pharmaceuticals are a real prospect, it will be interesting to see if the debate
is waged with equal vigour when the potential beneficiaries are poor people who
disproportionately bear the ravages of disease.
Kids infected at birth may
be outliving mothers, expert says
Lifestyle
TUESDAY, Feb. 2, 2010(HealthDay
News) -- In a study that highlights the growing crisis of birth-acquired HIV in
teens and young adults, new research has found that nearly 50 percent of youths
aged 10 to 18 who were admitted to two public hospitals in Zimbabwe were
infected with HIV, the virus that causes AIDS.
The HIV-positive
adolescents were more likely to have stunted growth, delayed puberty and to have
a mother who was infected with HIV or who had died of AIDS, the study found.
The researchers said that
69 percent of HIV-positive adolescents were admitted to the hospital because of
infections, such as tuberculosis or pneumonia, compared with 19 percent of
youths who did not have HIV. Also, 22 percent of the HIV-infected youths and 7
percent of the HIV-negative youths died while hospitalized.
The study is published
online in the February issue of PLoS Medicine.
Preventive efforts needed
to reduce transmission from mother to child, experts say
THURSDAY, Feb. 4, 2010 (HealthDay
News) -- Rates of HIV infection in infants are significantly higher among blacks
and Hispanics than whites, and preventive measures are needed to reduce the
disparity, a new government report says.
Although the number of
HIV-infected infants has declined overall, among black babies, the rate of
perinatal HIV infection -- meaning transmission at the time of birth -- is 23
times higher than for whites, and among Hispanics, the rate is four times
higher, according to findings published in the Feb. 5 issue of the Morbidity and
Mortality Weekly Report, from the U.S. Centers for Disease Control and
Prevention.
The average rate of
perinatal infection in the
Overall, while black and
Hispanic children under age 1 account for only 37 percent of the population,
they represent 85 percent of all perinatal HIV diagnoses, the authors noted.
The researchers, who
analyzed data from 34 states from 2004 to 2007, noted that transmission from an
HIV-infected mother to her child can be significantly reduced through preventive
measures.
And they noted some good
news: The annual rate of perinatal HIV diagnosis dropped between 2004 and 2007,
dipping from 14.8 to 10.2 per 100,000 among blacks and from 2.9 to 1.7 per
100,000 in Hispanics.
But further reductions are
necessary and achievable, the authors said, pointing to a transmission goal of
less than 1 percent for infants born to HIV-infected women and fewer than one
transmission per 100,000 live births.
Primary HIV prevention in
women is key, the authors noted, and efforts should be specifically directed
towards black and Hispanic women. All HIV-positive women who are pregnant should
have access to quality health care and take advantage of preventive measures,
including early treatment with antiretroviral medications, the report stated.
For the best outcomes, the
authors recommend the following:
HIV infection should be
diagnosed before or early in pregnancy
All moms-to-be should
receive prenatal care
HIV-positive women should
follow an antiretroviral medication regimen throughout pregnancy
A cesarean delivery should
be scheduled at 38 weeks' gestation if the virus has not been suppressed
Antiretroviral medication
should be taken during labor and delivery
Newborns exposed to HIV
should receive antiretroviral medication within the first hours after birth and
for the first six weeks of life.
Overall, "the total
number of annual perinatal HIV infections in the
FDA adds warning language
to Bristol-Myers HIV drug after dozens of reports of bleeding
The Associated Press,
February 1, 2010
Federal health officials
said Monday that patients taking a Bristol-Myers Squibb drug for HIV are at risk
of a rare, but potentially fatal, liver disorder.
The Food and Drug
Administration said it has received 42 reports of the disorder since Videx was
approved in 1991. Four patients died from bleeding or liver failure after
developing the problem, known as non-cirrhotic portal hypertension.
The problem involves
dangerously slow blood flow though the liver, which can cause veins in the
esophagus to swell. These veins are thin and can cause burst, causing
potentially deadly bleeding.
FDA says it is keeping the
drug on the market because its benefits to patients outweigh its risks. Videx
capsules prevent HIV from multiplying and are used in combination with other
virus-fighting drugs in adults and children.
The agency added warnings
to the drug's label about the signs and symptoms of the liver disorder.
According to the new labeling, patients "should be monitored for early
signs of portal hypertension during routine medical visits."
New York-based Bristol
Myers Squibb said the FDA is also requiring the company to design a medication
guide for patients that details Videx's risks.
"As with all our
medicines, we work closely with the FDA to monitor safety events," the
company said in a statement.
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The Associated Press,
February 2, 2010
Shares of Achillion
Pharmaceuticals Inc. advanced Tuesday after the company said it entered a
partnership to develop and sell its hepatitis B and HIV drug candidate
elvucitabine in
Late Monday, Achillion
announced a marketing partnership with GCA Therapeutics. Terms were not
disclosed, but the companies said GCA will have the right to develop and sell
elvucitabine in
The venture will handle
all development and regulatory activity and cover the costs associated with that
work. Achillion could receive milestone payments as the drug passes through
testing and review, and royalty payments of more than 10 percent on sales in
those areas.
Achillion has completed
midstage tests of elvucitabine in both hepatitis B and HIV.
Shares of the
In a note to clients,
Wedbush Morgan analyst Y. Katherine Xu said she expects the stock to rise
further if Achillion can find a partner to help develop its hepatitis C drug
candidate ACH-1625. She believes that partnership would be more important than
the elvucitabine agreement for now.
"Although
Xu upgraded Achillion
shares to "Outperform" from "Neutral." She expects the stock
to rise to $5 per share. The shares have traded between $1.10 and $3.89 over the
last year, and last reached $5 in March 2008.
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Associated Press. All rights reserved. This material may not be published,
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