STUDIES SHED LIGHT ON AIDS 'COCKTAILS'
AP 11 July 2001
Chicago -- Two new studies suggest that the slight blips in virus
levels that many AIDS patients experience while taking combination drug
therapy do not necessarily mean the treatment is failing after all.
The findings could have significant implications for AIDS treatment.
Doctors generally try to suppress the AIDS virus to levels undetectable by
routine tests. Up to now, doctors believed that when HIV rises back to
detectable levels, it means that the virus is becoming drug-resistant and
that the patient has to switch medications.
The new studies suggest that slight, intermittent surges in virus
levels do not always mean the virus is becoming drug resistant, and
switching drugs may not be necessary.
"Unnecessary regimen switching may result in disruption of a patient's
medication routine, toxic effects from new drugs, and premature discarding
of useful drugs," according to one of the studies, led by Dr. Diane Havlir
of the University of California in San Diego.
The studies were published in today's Journal of the American Medical
The studies "question some of the basic principles upon which therapy
is based," said Dr. Steven Deeks of the University of California in San
Francisco's AIDS Program, who wrote an accompanying editorial. The findings
indicate that "complete viral suppression is rarely achieved with current
therapies." Patients in both studies received standard drug cocktails of
the older AIDS workhorse medications AZT and 3TC, plus protease inhibitors,
which have transformed the disease into a manageable chronic ailment for
Havlir and colleagues analyzed data on 241 patients followed for about
16 months and a group of 13 followed for about 4 1/2 years.
"Intermittent viremia" - occasional, detectable AIDS virus levels -
occurred in about 40 percent of the 241 patients and in six of the
13. Persistently high virus levels indicating the treatment failed
occurred in 30 patients, but were no more likely to occur in those with
In the other JAMA report, Dr. Deborah Persaud from Johns Hopkins
University Children's Center and colleagues studied blood samples of 20
AIDS patients on standard drug treatment for at least two years. They found
that standard treatment seemed to block virus mutation even in patients
with intermittent blips of virus activity. The AIDS virus develops drug
resistance by mutating.