Enrollment has been stopped in a clinical trial of mother to child HIV transmission, Pediatric ACTG Protocol 185, due to a welcome but unexpectedly low rate of infant infection which made comparison of the standard and experimental treatments impossible. Pediatric ACTG Protocol 185 was a randomized, controlled clinical trial designed to test whether HIVIG (an immune globulin containing high levels of antibodies to HIV) reduced transmission of HIV from infected pregnant women to their infants when added to the standard AZT-based preventive treatment regimen. The comparison group received AZT and standard intravenous immunoglobulin (IVIG) that does not contain HIV antibodies.
Although enrollment will be stopped, the trial will continue with the standard AZT treatment and followup of mothers and children, it was announced by the study's sponsors, the National Heart, Lung and Blood Institute; the National Institute of Child Health and Human Development, and the National Institute of Allergy and Infectious Diseases.
The trial allowed enrollment of HIV-infected women with more advanced disease and lower CD4+ T cell count than had Pediatric ACTG Protocol 076, the 1994 clinical trial that demonstrated that AZT decreases mother-to-child HIV transmission by two-thirds. The Pediatric ACTG Protocol 185 trial enrolled HIV-infected pregnant women with CD4+ T cell count less than or equal to 500/mm3 who were receiving AZT during pregnancy for medical indications. Women could receive other nucleoside antiretroviral agents, if required, for their own health. It was anticipated that transmission from mother to child in a population of women with advanced disease, even when receiving AZT, would be significantly higher than that observed in women with less severe disease receiving AZT (in Pediatric ACTG Protocol 076, the transmission rate was 7.6% from AZT-receiving women).
On March 21, 1997, the study's independent Data and Safety Monitoring Board (DSMB) review
Contact: Robert Bock
NIH/National Institute of Child Health and Human Development