Immune response boosted by prior interruptions in therapy
An unusual group of HIV-infected patients who stopped taking antiviral drugs yet continued to suppress HIV replication may have somehow boosted their immune response against the virus by temporary therapy interruptions, researchers from the Aaron Diamond AIDS Research Center at Rockefeller University report. Although scientists strongly advise against halting drug therapy -- because the virus usually comes surging back -- this observation suggests that some HIV-infected people can suppress the virus without drugs if they have strong immune responses.
The study focuses on only six subjects, so its widespread implications for treating the general population of HIV-infected people are unclear. But if researchers can identify the mechanism by which the immune response is strengthened in patients who interrupted treatment, they might be able to design vaccines that infected patients could take to keep the virus at low levels even when medication is halted.
"We don't want people to stop taking anti-HIV drugs," says Gabriel Ortiz, an M.D., Ph.D. biomedical fellow and first author of the paper. "But the observation that has been made is pretty striking, because it does suggest that artificially vaccinating infected patients who are taking drugs may help maintain virus at a low level if they stop taking drugs for whatever reason."
Suppressing HIV at the lowest possible level is important because the
amount of virus in an infected person is the most important factor determining
how soon he or she develops full-blown AIDS. Anti-HIV drugs have proven to be
effective in keeping the virus at undetectable levels, but they must be taken
every day for an indefinite period. Many patients have trouble sticking to the
regimen because the drugs can have toxic effects and can cause adverse events in
the body. In addition, this highly active antiretroviral therapy (HAAR
Contact: Jim Stallard