Foscarnet Effects on the Rat Pregnancy Outcome

Abstract

There are few long-term data on which to base decisions of drug management of HIV infection in pregnancy. The determination of safe medications must take into consideration the need for certain drugs and the possibility of inadvertent fetal exposure because of unplanned pregnancies. The aim of this study was to evaluate the effects of foscarnet on the entire period of rat pregnancy. Female pregnant rats were randomly assigned to four treatment groups (n = 10): one control (C)-treated with the drug vehicle (bidestilled water) and three experimental groups (E1, E2 and E3)-treated with 180, 360 or 720 mg/Kg of foscarnet, respectively. Rats were treated by gavage once daily. The treatment period extended from the first until the 20th day of pregnancy. Body weights were recorded weekly along this period. At term, the rats were sacrificed, the implantation sites and the number of fetuses and resorptions were recorded. The fetuses were evaluated for externally visible abnormalities under a stereomicroscope. No differences in body weights among the groups were observed; however, foscarnettreated rats showed reduced fetal and placental weights. The incidence 137of resorptions and major malformations (shortening of limbs) in the E3 group was significantly raised. Foscarnet treatment during the entire period of rat pregnancy can produce definite toxic effects, mainly on the placental and fetal compartments.

British HIV Association guidelines on the management of opportunistic infection in people living with HIV: Considerations in pregnancy 2024

“…Foscarnet has been associated with fetal skeletal abnormalities in animal studies [107, 108]. A single case report demonstrated the safe use of foscarnet in the second trimester of pregnancy for a non‐CMV indication with no adverse fetal effects [109].…”