Interrupting HIV Treatment May Boost Immune System

From the WebMD Archives

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 system.

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 recipe."

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.

Vital Information:

  • 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 the blood.
  • Neither patients nor physicians should attempt to try this therapy on their own, as it is still in the early phases of research.