Flow-dependent transfer of antipyrine in the human placenta in vitro

f Nowadays, antiretroviral therapy is recommended during pregnancy to prevent mother-to-child transmission of HIV. However, for many antiretroviral drugs, including maraviroc, a CCR5 antagonist, very little data exist regarding placental transfer. Besides, various factors may modulate this transfer, including efflux transporters belonging to the ATP-binding cassette (ABC) transporter superfamily. We investigated maraviroc placental transfer and the influence of ABC transporter expression on this transfer using the human cotyledon perfusion model. Term placentas were perfused ex vivo for 90 min with maraviroc (600 ng/ ml) either in the maternal-to-fetal (n ‫؍‬ 10 placentas) or fetal-to-maternal (n ‫؍‬ 6 placentas) direction. Plasma concentrations were determined by ultra performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). Fetal transfer rates (FTR) and clearance indexes (CLI) were calculated as ratios of fetal to maternal concentrations at steady state (mean values between 30 and 90 min) and ratios of FTR of maraviroc to that of antipyrine, respectively. ABC transporter gene expression levels were determined by quantitative reverse transcription (RT)-PCR and ABCB1 protein expression by Western blotting. For the maternal-to-fetal direction, the mean FTR and CLI were 8.0% ؎ 3.0 and 0.26 ؎ 0.07, respectively, whereas the mean CLI was 0.52 ؎ 0.23 for the fetal-to-maternal direction. We showed a significant inverse correlation between maraviroc CLI and ABCC2, ABCC10, and ABCC11 placental gene expression levels (P < 0.05). To conclude, we report a low maraviroc placental transfer probably involving ABC efflux transporters and thus in all likelihood associated with a limited fetal exposition. Nevertheless, these results would need to be supported by in vivo data obtained from paired maternal and cord blood samples.

Section: Methodsmentioning

confidence: 99%

Placental Transfer of Maraviroc in an Ex Vivo Human Cotyledon Perfusion Model and Influence of ABC Transporter Expression

Vinot

Gavard

Tréluyer

et al. 2013

“…The lower limit of quantification for antipyrine was 0.01 mg/liter. Maternal-to-fetal transfer parameters were calculated at steady state according to the formulas of Challier et al (13). The fetal transfer rate (FTR) is the ratio of fetal to maternal concentrations, and the clearance index (CLI) is the ratio of the FTR of rilpivirine over the FTR of antipyrine.…”

Section: Rilpivirine (4-[[4-[[4-[(e)-2-cyanoethenyl]-26-dimethylphenmentioning

confidence: 99%

“…The rilpivirine concentrations were targeted to be within the range of clinical peak plasma levels (maximum concentration of drug in serum [C max ]). Antipyrine, an inert molecule which freely diffuses through the placenta, was added at 20 mg/liter as a marker to validate the cotyledon's viability throughout the experiment (13).…”

Section: Rilpivirine (4-[[4-[[4-[(e)-2-cyanoethenyl]-26-dimethylphenmentioning

confidence: 99%

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

Mandelbrot

Duro

Belissa

et al. 2015

e Placental transfers of the HIV nonnucleoside reverse transcriptase inhibitor rilpivirine were investigated in 8 term human cotyledons perfused with rilpivirine (400 ng/ml) in the maternal-to-fetal direction. The mean fetal transfer rate (FTR) (fetal/maternal concentration at steady state from 15 to 90 min) was 26% ؎ 8% (mean ؎ standard deviation), and the clearance index (rilpivirine FTR/antipyrine FTR) was 61% ؎ 20%. This shows that rilpivirine crosses the placenta at a relatively high rate, suggesting that the fetus is exposed to the compound during treatment of the mother.A ntiretroviral drugs are remarkably effective for preventing vertical transmission of HIV-1, resulting in a decline in the rate of transmission, which is now less than 0.5% in France (1, 2). Current guidelines recommend antiretroviral therapy for all HIVinfected pregnant women for their own health and to prevent transmission (3, 4)., a diarylpyrimidine analog, is a nonnucleoside reverse transcriptase inhibitor (NNRTI) which is increasingly used to treat HIV infection and in recent guidelines is considered a first-line treatment. It is available in a single-tablet formulation in combination with tenofovir and emtricitabine (Complera-Eviplera). Rilpivirine is classified as a pregnancy category B drug by the Food and Drug Administration (4), which means that animal studies have failed to demonstrate a risk to the fetus, but there have been no adequate and well-controlled studies in HIV-1-infected pregnant women. To date, only one report has been published on two cases of rilpivirine use in pregnant women (5), in which the plasma concentrations of rilpivirine were lower than would be expected in nonpregnant women. Placental transfer was studied in one of these two cases. Currently, there are no data on the safety of rilpivirine use during pregnancy.Determining fetal exposure is important for all new medications in order to estimate the potential for preexposure prophylaxis and the risk for toxicities to the fetus. A number of adverse events have been reported following perinatal exposure to antiretroviral medications, including mitochondrial diseases (6). Since data from animal studies are difficult to extrapolate to humans due to differences in placental physiology, other preclinical approaches are required.The ex vivo human cotyledon is an accepted model used to study and interpret placental transfer (7,8). The purpose of this study was to investigate the placental transfer of rilpivirine in an ex vivo perfused human cotyledon.Placentas were collected after uncomplicated pregnancy with full-term delivery (Ն37 weeks gestational age) in mothers who were seronegative for HIV and hepatitis B and C viruses and had taken no medication, except for vitamin supplements and perimedullar analgesia. They were collected in a single center, the maternity ward of the Hôpitaux Universitaires Paris-Nord Val de Seine (Colombes, France), and were rapidly perfused on site. Written informed consent was obtained from each of the women who donated a placenta, acc...

“…Antipyrine concentrations were determined by liquid chromatography with UV detection, as previously described (11,12). For maternal-to-fetal transfer, the fetal transfer rate (FTR) and clearance index (CI) were calculated under steady-state conditions as the ratios of fetal to maternal concentrations, and the FTR of RLT to that of antipyrine, respectively (13). An FTR of antipyrine of Ն20% was required to validate each experiment.…”

mentioning

confidence: 99%

Bidirectional Transfer of Raltegravir in an Ex Vivo Human Cotyledon Perfusion Model

Vinot

Tréluyer

Giraud

et al. 2016

i Placental transfer of the HIV integrase inhibitor raltegravir (RLT) was investigated in term human cotyledons in the maternalto-fetal (n ‫؍‬ 3) and fetal-to-maternal (n ‫؍‬ 6) directions. In the maternal-to-fetal direction, the mean ؎ standard deviation (SD) fetal transfer rate (FTR) was 9.1% ؎ 1.4%, and the mean ؎ SD clearance index (IC), i.e., RLT FTR/antipyrine FTR, was 0.28 ؎ 0.05. In the fetal-to-maternal direction, the mean ؎ SD CI was 0.31 ؎ 0.09. Placental transfer of RLT was high in both directions.A ntiretroviral therapy (ART), in addition to its benefits for the health of people living with HIV, is effective for preventing mother-to-child transmission (MTCT) of HIV-1, which in industrialized countries has been reduced to Ͻ1% (1-3). Raltegravir (RLT) belongs to the integrase strand transfer inhibitor (INSTI) class of antiretroviral agents, which act by blocking the insertion of viral cDNA into human genomic DNA (4). RLT is classified in category C by the Food and Drug Administration (FDA), meaning that fetal risk has been detected in animal reproduction studies, but there have been no adequate studies conducted in pregnant women. The placental transfer of currently used antiretrovirals varies considerably between classes and individual molecules, and nucleoside reverse transcriptase inhibitors (NRTIs) have high placental transfer (5, 6), whereas protease inhibitors have lower placental transfer (7,8). The purpose of this study was to investigate the bidirectional placental transfer of RLT by using the ex vivo model of the human perfused cotyledon.Nine term placentas from normal pregnancies (from 38 to 42 weeks of gestational age) were obtained from Louis Mourier Hospital (Colombes, France). All mothers were seronegative for HIV infection and hepatitis B and C, and they had taken no medication other than oxytocin or epidural anesthesia during labor. Written informed consent was obtained for all placentas. RLT base was provided by Merck (Paris, France), antipyrine-phosphate-buffered saline (PBS) was purchased from Sigma-Aldrich (SaintQuentin-Fallavier, France), and other chemicals were from Invitrogen (Cergy-Pontoise, France).Placentas were perfused in an open double-circuit system, as previously described (9). Perfusion experiments were started within 20 min after delivery. After visual examination, an intact cotyledon was selected, and a truncal branch of the chorionic artery and the associated vein were cannulated; the establishment of venous flow after perfusion of the fetal artery flow confirmed the viability of the cotyledon. On the maternal side, the perfused area progressively whitened, allowing visualization of the cotyledon. The cotyledon was placed into the perfusion chamber and maintained at 37°C, with the maternal side upward. The intervillous space on the maternal side was perfused by two needles piercing the basal plate. The two circuits were pumped separately by peristaltic pumps. The fetal and maternal flows were 6 and 12 ml/min, respectively, and the perfusion length was 90 min. The p...