<<Gallo recently was quoted, saying that there has been a bit of luck observed in the course of PI therapy....that some of the patients on PI's see a rebound in the face of sustained viral titers. Anybody know what he was hinting at?>>
The Washington Post; Thursday, July 2, 1998;
GENEVA, July 1 -- When it comes to three-drug combination
therapy for AIDS, treatment "failure" may not be quite as bad
as people once thought.
As long as AIDS patients on "triple therapy" have some increase
in a crucial class of immune system cells, they stand a good
chance of getting markedly healthier -- even if their
bloodstreams still carry swarms of the human immunodeficiency
virus (HIV), research presented at the 12th World AIDS
Conference suggests.
The details of this phenomenon -- clinical success in the face
of microbiological failure -- are still scant and sketchy.
Nevertheless, it's beginning to appear that triple therapy
doesn't produce the all-or-nothing results AIDS researchers
expected when the treatment was introduced about two years ago.
"This is still mostly at the level of anecdotes, but there are
a lot of anecdotes," said Anthony S. Fauci, a leading AIDS
researcher at the U.S. National Institutes of Health. "Almost
everyone you talk to has a couple of these patients. It may
require redefining what failure means."
Triple therapy, which generally includes a drug from the
protease inhibitor family, has two major effects. It suppresses
the growth of HIV, and it allows a class of cells called CD4
lymphocytes to rebound.
Suppression of the virus to a level so low that it can't be
measured -- this generally means less than 200 viruses per
milliliter of blood -- is the current goal. Patients whose
"viral load" is still in the measurable range are often
considered treatment failures. Frequently, they're switched to
a different three-drug combination, in pursuit of total
suppression.
It now appears that many of these people actually can do quite
well -- provided their CD4 counts rise and stay up.
Two researchers, one from France and the other from
Switzerland, provided some evidence of this today.
Christophe Piketty, a physician at Hospital Broussais in Paris,
reported on the experience of 162 people with advanced AIDS.
Their CD4 counts showed evidence of severe immune system
damage, and they had nearly 100,000 viruses per milliliter of
blood. None had tried protease inhibitors, although most had
had about three-years worth of treatment with less effective
antiviral drugs.
Triple therapy with a protease drug produced the desired result
in slightly more than half the patients -- their viral load
fell to low levels and their CD4 counts rose. About one-fifth,
however, got only one of those effects and not the other.
When Piketty and his colleagues looked at the number of serious
illnesses the patients suffered in the ensuing nine months,
they saw something unexpected. The people who experienced only
a rise in their CD4 count (but no significant drop in viral
load) did as well as the people who had achieved both those
goals. On the other hand, the people whose viral loads had
dropped but who hadn't seen their CD4 cells rise did as poorly
as those whose treatment had failed by both measures.
A presentation by Swiss scientist Daniel Kaufmann suggested
that the phenomenon the French researchers found may be
long-lasting. He and his colleagues treated about 90 AIDS
patients with triple therapy. The patients had all taken some
antivirals in the past. As with the French group, there was a
variety of responses, including a rise in CD4 count but only a
transient drop in viral load in about a third. The CD4 counts
in those patients were still up nearly two years after the
start of treatment, and they were relatively protected from
opportunistic illnesses. Those who stopped triple therapy for
some reason saw their CD4 cells drop and their risk of
complications rise.
In both the French and Swiss studies, the people with the
incomplete but clinically beneficial response to triple therapy
followed the exacting pill-taking schedule they were
prescribed. Their experience raises the question: Do people who
never get a full response to triple therapy because they forget
to take their pills also experience a real benefit from such
treatment?
The question is relevant because some of the most marginalized
HIV patients in the United States turn out to be much more
reliable at taking their medicines than many doctors assume --
but are still less than perfect as demanded by current AIDS
therapy.
In another presentation today, David Bangsberg of the
University of California in San Francisco reported that a dozen
AIDS patients living in homeless shelters or cheap hotels took
80 percent of the triple-therapy pills they were prescribed. He
said this is not good enough. |
