A woman’s response to HIV treatment with drug combinations that contain nevirapine is improved if at least six months have passed after she received the drug as a single dose during labor to prevent passing HIV on to her child. Conversely, the response to treatment with nevirapine-containing combinations is diminished if less than six months has passed since the preventive regimen. The response to treatment is measured by the reduction of HIV in the blood.
A single dose of nevirapine is a common preventive regimen given to pregnant women during labor in resource-poor countries where the standard, more expensive, multi-drug treatments are not widely available. Previous studies have indicated, however, that the single nevirapine dose could make the virus resistant to the drug, which may make it less likely that a woman will respond to nevirapine if she needs it later, as part of a multi-drug anti-HIV regimen, to safeguard her own health. The single dose of nevirapine eliminates most of the copies of HIV that infect a patient, except for a few mutant copies that are genetically resistant to the drug. Researchers were concerned that as these remaining mutants multiplied, mutant HIV would not respond to nevirapine when it was used later as part of a multi-drug regimen to treat HIV infection.
Fortunately, nevirapine, given once during labor, alone or in combination with a short course of zidovudine (AZT) during pregnancy, provides an inexpensive, effective way to reduce the chances that a pregnant woman will pass HIV on to her child.
These findings were reported by researchers funded in part by the National Institutes of Health and appear in the January 11 New England Journal of Medicine.
Robert Bock or
Marianne Glass Miller
Message posted by: Rashmi Nemade