Lack of activity of fusidic acid against human immunodeficiency virus in monocytes.

The effect of fusidic acid on the multiplication of human immunodeficiency virus in monocyte-derived macrophages was examined in in vitro cultures. Virus titers, measured by reverse transcriptase and by p24 antigen in the supernatants and in lysed cells, were reduced in some experiments by 50 micrograms/ml or more; in other experiments, 10 micrograms of fusidic acid per ml added to the cells simultaneously with the virus inoculation reduced virus titers. The effect was comparable in peripheral blood lymphocytes. The drug was generally toxic to the cells, both macrophages and peripheral blood lymphocytes, in concentrations of 50 micrograms/ml or more.