Here's what Reuter's had to say:
W A S H I N G T O N, Nov. 13 -
Scientists who helped develop the
"cocktail" of three drugs now used
widely to keep AIDS at bay in people
infected with HIV admit that it
cannot cure the infection.
They said tests showed the AIDS virus
still lurks in the immune system cells it infects,
even after years of taking the powerful
drugs.
"The bad news is we can't yet get rid of
the virus entirely. The number of immune
system cells that remain infected with HIV
declines only very slowly," said Dr. Robert
Siciliano, an associate professor of medicine
at Johns Hopkins University in Baltimore.
"But the good news is that as long as
people infected with HIV keep taking the
triple-drug cocktail, they have an excellent
chance of surviving the infection for a long
time, without developing symptoms of the
disease."
Tests have shown that triple therapy, using
a combination of three different AIDS drugs,
can knock the virus down to undetectable
levels after two to four months.
The usual regime consists of two of the
first-generation of AIDS drugs such as AZT,
ddI or 3TC and known as reverse
transcriptase inhibitors, plus a protease
inhibitor such as saquinavir or ritonavir.
When the results were announced at a big
AIDS conference last year, researchers
dared to whisper the word "cure," although
only very softly and tentatively.
Just One Bad Cell .
Dr. David Ho of the Aaron Diamond AIDS
Research Center in New York and
colleagues at first planned to take one of
their patients off the drugs, first after 18
months, then after two years.
But they shelved those plans after tests
showed the virus still hiding in the body, and
even one infected cell could release enough
virus to reinfect a person.
Ho said earlier this year that mathematical
models showed the virus could be
completely eradicated after three years, but
now abandons even this hope in a report in
the journal Science.
The Johns Hopkins and Aaron Diamond
researchers looked for HIV in 22 patients
who had been on the cocktail therapy for as
long as 30 months.
People on this cocktail therapy have to
take handfuls of pills every day-many at set
times. The side-effects can be very
unpleasant and include nausea, so this group
was watched very carefully to make sure
they took every pill on time.
HIV Presistent
"We studied patients whose viral loads had
been undetectable for prolonged periods of
time," said Dr. Joel Gallant, director of the
AIDS outpatient clinical at Johns Hopkins.
Nonetheless, the researchers were able to
routinely tease HIV out of "resting" CD4
cells-helper T-cells that had been infected
but were not currently in replicative phase.
"The team also showed that when the
resting cells were stimulated to reproduce,
the AIDS virus also replicated," said Diana
Finzi, a postgraduate student who led the
work.
But there was some positive news. While
on the triple-drug regime, all the patients
grew more healthy, uninfected immune
system cells. Also, the virus was not able to
replicate-so it was also not able to mutate
into new, drug-resistant forms.
"So this is a strong argument for not taking
these patients off triple-drug therapy,"
Siciliano said.
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