[Use of enfurvitide in pregnancy in HIV positive women in seven cases]

Action of enfuvirtide on the pregnancy of albino rats (Rattus norvegicus albinus, Rodentia, Mammalia): biological assay and functional and histological analyses of exposed maternal-fetal organs

OBJECTIVE

• No drug related fetal malformations. • No adverse effects on vital organ functions. To assess the effects of enfuvirtide on pregnancy in albino rats and their fetuses.

METHODS

Forty pregnant EPM 1 Wistar rats were randomly allocated into four groups: control (E) (distilled water twice/day), G1 (4mg/kg/day enfuvirtide), G2 (12mg/kg/day enfuvirtide), and G3 (36mg/kg/day enfuvirtide) groups. On the 20th day of gestation, the rats were anesthetized and subjected to cesarean section. Their blood was collected for laboratory analysis, and they were sacrificed. The offspring's fragments of their kidneys, liver, and placentas and the maternal rats' fragments of their lungs, kidneys, and liver were separated in the immediate postpartum period for light microscopy analysis.

RESULTS

No maternal deaths occurred. In the second week at the end of pregnancy, the mean weight of the G3 Group was significantly lower than that of the G2 Group (p=0.029 and p=0.028, respectively). Analyzing blood laboratory parameters, the G1 Group had the lowest mean amylase level, and the G2 Group had the lowest mean hemoglobin level and the highest mean platelet count. In the morphological analysis, there were no changes in organs, such as the kidneys and liver, in both the maternal rats and offspring. Three maternal rats in the G3 Group had pulmonary inflammation in the lungs.

CONCLUSION

Enfuvirtide has no significant adverse effects on pregnancy, conceptual products, or functional alterations in maternal rats.

Pharmacokinetics and Placental Transfer of Elvitegravir, Dolutegravir, and Other Antiretrovirals during Pregnancy

The integrase inhibitors elvitegravir (EVG) and dolutegravir (DTG) rapidly decrease the plasma HIV-1 viral load, a key factor in the prevention of maternal-to-fetal transmission of HIV-1. No data have been reported on the concentrations of these drugs in cord blood, maternal peripheral blood mononuclear cells (PBMCs), or placental tissue in pregnant women. We present in vivo pharmacokinetic data on antiretrovirals (ARV) within maternal and cord blood and within placentae from HIV-1-infected pregnant women. Maternal blood and cord blood were obtained from women receiving EVG, cobicistat, tenofovir disoproxil fumarate, and emtricitabine as a single fixed-dose combination formulation or DTG as part of a combination regimen. Plasma and PBMCs from maternal and cord blood were obtained along with villous placental samples. Drug concentrations were simultaneously determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Utilizing medians and ranges to interpret our data, we compared the drug concentration ratios between different matrices (maternal and cord blood plasma, PBMCs, and placenta). All five agents transferred from maternal into fetal circulation via the placenta. Concentration ratios for EVG, cobicistat, tenofovir, and emtricitabine (n = 10) and DTG (n = 3) were determined between cord plasma and placenta, cord and maternal plasma, and cord PBMCs and maternal PBMCs. TFV moves from maternal plasma through the placenta to the cord blood and then into cord PBMCs, where it is phosphorylated into its active forms (TFV diphosphate). These five ARVs were detected in each of the compartments, highlighting transfer of these agents from the maternal into the fetal circulation.

Protecting the fetus against HIV infection: a systematic review of placental transfer of antiretrovirals

BACKGROUND

Maternal-to-fetal transfer of antiretroviral drugs contributes to prevention of vertical transmission of HIV.

OBJECTIVE

This systematic review discusses published studies containing data pertaining to the pharmacokinetics of placental transfer of antiretrovirals in humans, including paired cord and maternal plasma samples collected at the time of delivery as well as ex vivo placental perfusion models.

METHODS

Articles pertaining to placental transfer of antiretrovirals were identified from PubMed, from references of included articles, and from US Department of Health and Human Services Panel on Treatment of HIV-infected Pregnant Women and Prevention of Perinatal Transmission guidelines. Articles from non-human animal models or that had no original maternal-to-fetal transfer data were excluded. PRISMA guidelines were followed.

RESULTS

A total of 103 published studies were identified. Data across studies appeared relatively consistent for the nucleoside reverse transcriptase inhibitors (NRTIs) and the non-nucleotide reverse transcriptase inhibitors (NNRTIs), with cord to maternal ratios approaching 1 for many of these agents. The protease inhibitors atazanavir and lopinavir exhibited consistent maternal-to-fetal transfer across studies, although the transfer may be influenced by variations in drug-binding proteins. The protease inhibitors indinavir, nelfinavir, and saquinavir exhibited unreliable placental transport, with cord blood concentrations that were frequently undetectable. Limited data, primarily from case reports, indicate that darunavir and raltegravir provide detectable placental transfer.

CONCLUSION

These findings appear consistent with current guidelines of using two NRTIs plus an NNRTI, atazanavir/ritonavir, or lopinavir/ritonavir to maximize placental transfer as well as to optimally suppress maternal viral load. Darunavir/ritonavir and raltegravir may reasonably serve as second-line agents.

The management of HIV-infected pregnant women

PURPOSE OF REVIEW

The purpose of this article is to update the current practice in the management of HIV-infected pregnant women and present evidence-based recommendations for the reduction of mother-to-child transmission.

RECENT FINDINGS

Early and sustained control of HIV viral replication is associated with decreasing residual risk of transmission and favors initiating antiretroviral drugs sufficiently early in naive women to suppress viral replication by the third trimester; however, this potential benefit must be balanced against the unknown long-term outcome of first-trimester drug exposure. Efavirenz should whenever possible be avoided in the first trimester of gestation, but its use seems well tolerated for 39 days after last menstrual period when the neural tube closes. Raltegravir may be considered in special circumstances in pregnancy.

SUMMARY

The HIV viral load and the risk factors for prematurity must be considered when deciding when to start antiretroviral treatment in each individual pregnant woman. A ritonavir-boosted protease inhibitor combined with two nucleoside reverse transcriptase inhibitors is currently the most widely used regimen. Among protease inhibitors, lopinavir combined with ritonavir is the most frequently used; however, atazanavir combined with ritonavir is a good alternative. Elective cesarean section is the best delivery mode for pregnant women with viral loads more than 50  copies/ml.