Interrupting HIV Treatment May Boost Immune System
Jan. 21, 2000 (Cleveland) -- For most people with HIV, treatment with the
potent combination of drugs called HAART (highly active retroviral therapies)
will suppress the virus in their blood, but if treatment is stopped the virus
immediately rebounds. Now a team of international researchers is suggesting
that controlling the interruptions of treatment may allow the body's immune
system to figure out a way to attack the rebounding virus and, eventually, the
immune system may be able to control the virus without help from drugs.
This approach is called structured treatment interruption, and in today's
issue of the journal TheLancet the researchers report that it
appears to have worked in two of three patients they studied. All three
patients had never before been treated with HAART, and each time treatment was
restarted, HAART was able to control the virus in all three patients.
Lead author Franco Lori, MD, co-director of the Research Institute for
Genetic and Human Therapy (RIGHT) in Padua, Italy, and Washington, D.C., tells
WebMD that the goal of the current research is to "boost the immune system
like vaccine does."
A year ago, Lori and colleagues described the so-called Berlin patient, a
patient whose treatment with HAART was interrupted twice and then discontinued.
Two years after HAART was stopped, the "patient still had virus in the
body, but it has not rebounded in the blood," says Lori.
"This is very different from what we know from our research and from all
other research -- when HAART is interrupted the virus rebounds within
weeks," says Julianna Lisziewicz, PhD, a co-author of the study.
HIV is tracked by determining the amount of HIV genetic material circulating
in blood cells and by measuring the number of CD4 cells, the body's own defense
All patients were closely monitored to determine response to the HAART
treatments. The patients were treated for three weeks and then treatment was
interrupted for one week. After the initial interruption, patients were treated
with consecutive cycles of HAART for about three months, or until the virus was
undetectable, at which time treatment was interrupted. During interruptions,
patients were monitored very closely, and when virus in the body rose above a
certain level, treatment was restarted.
Lori says the goal of this sort of HIV treatment is to develop an approach
similar to the polio vaccine, "where you get three shots and then you are
immunized. We would like to describe a set number of cycles and then the immune
system can take over and control the virus."
Lori says that neither physicians nor patients should attempt a trial of
HAART interruption at this time, because "we are far from having a
Lisziewicz, who is a co-director of RIGHT, says that interrupting HAART
"can be very dangerous because the virus can rebound rapidly and can
progress very quickly to AIDS. We are monitoring these patients very closely,
daily even, to prevent that rapid rebound."
Lori and Lisziewicz are now enrolling 40 patients in a trial of structured
interruptions. "We are almost finished enrollment but don't expect to
report any findings for at least a year," says Lisziewicz.
- Researchers are attempting controlled interruptions of HIV therapy, in
hopes the body's own immune system can take over to fight the virus.
- In two of the three patients who underwent the experimental treatment, the
immune system was able to take over and prevent the virus from rebounding in
- Neither patients nor physicians should attempt to try this therapy on their
own, as it is still in the early phases of research.