Intriguing 'Drug Holidays' From HIV Treatment
July 13, 2000 (Durban, South Africa) -- Some preliminary research suggests that giving HIV patients a "drug holiday," where they do not have to take their drugs for up to a few weeks at a time, is feasible. However, both the scientists who presented the data at the 13th International AIDS Conference in Durban, South Africa, and other experts caution against patients -- and even their doctors -- trying this outside the confines of the tight control of a human study.
Researchers from the National Institute of Allergy and Infectious Disease (NIAID) in Bethesda, Md., said the data involves too few patients for any conclusion to be drawn from the work.
"We are not at all suggesting that this is a useful therapy," said Mike Dybul, MD, a researcher in the Laboratory of Immunoregulation at the NIAID, when presenting the two studies on drug holidays, called structured treatment interruptions (STI) by researchers.
The reports brought criticism from doctors and AIDS activists who worried that reports on treatment interruptions -- no matter how many caveats were attached -- would still encourage "willy-nilly" experimentation that could have disastrous results.
Dybul defended his work, saying, "It is intriguing information. It is interesting."
"You are playing with fire," cautioned Joseph Eron, MD, associate professor of medicine at the University of North Carolina at Chapel Hill.
Dybul discussed studies being conducted under the leadership of Anthony Fauci, MD, widely regarded as the preeminent American HIV researcher and director of the NIAID.
Dybul said they were investigating STI because:
- It has the potential to give patients relief from taking an enormous amount of pills required by the current standard treatment.
- It could hold promise for reducing side effects, such as unsightly changes in fat distribution in the body associated with long-term treatment.
- It could reduce expenses related to treatment. The current standard can cost $15,000 a year per patient.
Dybul said preliminary data on nine patients who were on a regimen that allowed them to be on drugs for two months and then off drugs for a month indicated that virtually every time they discontinued drugs, the virus rebounded. But when treatment was restarted, the virus became undetectable again, indicating that resistance to the drugs had not occurred.
"Resistance is one of the big risks involved in this type of study," Dybul said. "So far we haven't seen emergence of any drug resistant genes in these patients who have had instances of viral rebound."
Dybul said the goal of the study is to determine if the patients taking the drug holidays have the same outcomes as a similar group of patients who take their medications continuously.
Dybul also reported another study in which patients are receiving treatment for seven days and then are off for seven days -- in essence reducing drug intake by 50%. He has enrolled five patients in this study. He demonstrated that one patient -- on treatment for more than three months -- had no rebound of the virus. The study design calls for following these patients for six months to see if their virus can be continually suppressed with the drug interruptions.