A fair amount of data (584 first trimester and 1044 second/third trimester exposures according to the Antiretroviral Pregnancy Registry as of 31 July 2007 on pregnant women indicate no malformative or foeto/ neonatal toxicity.
The use of VIRAMUNE during pregnancy, if deemed necessary, may be considered.
No observable teratogenicity was detected in reproductive studies performed in pregnant rats and rabbits. In rats, a significant decrease in fetal body weight occurred at doses providing systemic exposure approximately 50% higher, based on AUC, than that seen at the recommended human clinical dose. The maternal and development no-observable-effect level dosages in rats and rabbits produced systemic exposures approximately equivalent to or approximately 50% higher, respectively, than those seen at the recommended daily human dose, based on AUC.
There have been no adequate and well controlled studies of nevirapine in pregnant women, nor are there reports of infants born to women who conceived while receiving nevirapine chronic dosing in clinical trials. Nevirapine readily crosses the placenta.
The US Antiretroviral Pregnancy Registry, which has been surveying pregnancy outcomes since January 1989, suggests that there is no signal apparent for birth defects related to VIRAMUNE. While the Registry population exposed and monitored to date is not sufficient to detect an increase in the risk of relatively rare defects, for VIRAMUNE sufficient numbers of first trimester exposures have been monitored to detect at least a 2-fold increase in risk of overall birth defects. These findings should provide some assurance in counselling patients.
Caution should be exercised when prescribing VIRAMUNE to pregnant woman. As hepatotoxicity is more frequent in women with CD4 cell counts above 250 cells/mm3, these conditions should be taken in consideration on therapeutic decision (see Precautions).
Women of childbearing potential should not use oral contraceptives as the sole method for birth control, since VIRAMUNE (nevirapine) might lower the plasma concentrations of these medications (see Precautions).
Consistent with the recommendation that HIV-infected mothers not breast-feed their infants to avoid risking postnatal transmission of HIV, mothers should discontinue breast-feeding if they are receiving VIRAMUNE.
In reproductive toxicology studies, evidence of impaired fertility was seen in female rats at doses providing systemic exposure, based on AUC, approximately equivalent to that observed following a human clinical dose of 400 mg/day.
No human data on fertility are available.