Weekly Intermittent Treatment: Caution
July 28, 2000
Press reports from the Durban conference mentioned a trial in Dr. Fauci's group at the U.S. National Institutes of Health in which antiretroviral treatment was given one week on and one week off. Physicians are concerned that some patients may try this without medical advice -- which could be very harmful.
It was not clear enough from the news reports that these patients were highly selected for the trial because their virus had already been very well suppressed by antiretroviral treatment. The idea was to reduce drug side effects by reducing the total amount of drugs used, taking advantage of the fact that when HIV is so well controlled, it does not come back at all in the first week after the drugs are stopped (or comes back just a little). Therefore, during the time off treatment, there was little or no viral replication to lead to resistance development. And before the virus could come back, the drugs were started again.
But the situation would be entirely different for patients whose virus has not been very well suppressed, because then much replication could take place during each week off treatment, while low drug levels were still in the body -- excellent conditions for the development of viral resistance.
Another reason for caution is that this report was from only five patients, who have only been treated 14 weeks (seven on-off cycles) so far. Also, in a research setting, patients can be tested to make sure that their virus is indeed not replicating during the time off the drugs.
Clearly this strategy is important for research -- but not at all ready for general use. Dr. Fauci warned "that many questions remain to be answered, including whether drug resistance will develop, and what the ultimate clinical course of patients receiving structured intermittent therapy will be. It is essential that these and other issues related to treatment interruptions be addressed before intermittent HAART can be recommended to an individual patient outside the setting of a controlled clinical trial."
Copyright 2000 by John S. James. Permission granted for noncommercial reproduction, provided that our address and phone number are included if more than short quotations are used.
This article was provided by AIDS Treatment News. It is a part of the publication AIDS Treatment News.