Placental Transfer of Darunavir in an Ex Vivo Human Cotyledon Perfusion Model

Placental transfer of the HIV protease inhibitor darunavir was investigated in 5 term human cotyledons perfused with darunavir (1,000 ng/ml) in the maternal to fetal direction. The mean ( the standard deviation [SD]) fetal transfer rate (FTR) (fetal/mater-nal concentration at steady state from 30 to 90 min) was 15.0% 2.1%, and the mean (SD) clearance index (darunavir FTR/ antipyrine FTR) was 40.3% 5.8%. This shows that darunavir crosses the placenta at a relatively low rate, resulting in fetal exposure. The use of antiretroviral drugs has allowed for a spectacularreduction inmother-to-child transmission (MTCT) ofHIV in the industrialized countries, with a current rate of 0.5 % in France (1, 2). Darunavir is an HIV protease inhibitor (PI) that is increasingly used in combination with other drugs to treat HIV infection. It is now considered a first-line option in pregnant women (3, 4), although few data are available to date on its effects during pregnancy. It is classified by the FDA in pregnancy cate-gory C (4), meaning that animal studies have failed to demon-strate a risk to the fetus, but there have been no adequate and well-controlled studies in pregnant women. Most of the advers