Objectives

Long-acting reversible contraceptives are effective contraceptives for women with HIV, but there are limited data on etonogestrel implant and antiretroviral therapy pharmacokinetic drug-drug interactions. We evaluated etonogestrel/antiretroviral therapy drug-drug interactions, and the effects of etonogestrel on ritonavir-boosted-atazanavir, ritonavir-boosted-lopinavir, and efavirenz pharmacokinetics.

Study design

We enrolled postpartum women using etonogestrel implants and receiving ritonavir-boosted-atazanavir, ritonavir-boosted-lopinavir, or efavirenz-based regimens between 2012 and 2015. Etonogestrel implants were inserted 2 to 12 weeks postpartum. We performed pharmacokinetic sampling pre-etonogestrel insertion and 6 to 7 weeks postinsertion. We measured antiretroviral concentrations pre and postetonogestrel insertion, and compared etonogestrel concentrations between antiretroviral regimens. We considered a minimum serum etonogestrel concentration of 90 pg/mL adequate for ovulation suppression.

Results

We collected pharmacokinetic data for 74 postpartum women, 22 on ritonavir-boosted-atazanavir, 26 on ritonavir-boosted-lopinavir, and 26 on efavirenz. The median serum concentrations of etonogestrel when co-administered were highest with etonogestrel/ritonavir-boosted-atazanavir (604 pg/mL) and etonogestrel/ritonavir-boosted-lopinavir (428 pg/mL), and lowest with etonogestrel/efavirenz (125 pg/mL); p < 0.001. Minimum concentration (C_min) of ritonavir-boosted-atazanavir and ritonavir-boosted-lopinavir were lower after etonogestrel implant insertion, but overall exposure, predose concentrations, clearance, and half-lives were unchanged. We found no significant change in efavirenz exposure after etonogestrel insertion.

Conclusions

Unlike efavirenz, ritonavir-boosted-atazanavir and ritonavir-boosted-lopinavir were not associated with significant decreases in etonogestrel concentrations. Efavirenz was associated with a significant decrease in etonogestrel concentrations.

Implications

The findings demonstrate no interactions between etonogestrel and ritonavir-boosted-lopinavir or ritonavir-boosted-atazanavir, but confirm the decreased efficacy of etonogestrel with efavirenz-based antiretrovirals. This information should be used to counsel women with HIV who desire long-acting reversible contraceptives.

What is known and objective

Tenofovir exposure is increased in non-pregnant adults when tenofovir disoproxil fumarate is coadministered with lopinavir/ritonavir. In pregnant women, tenofovir exposure is decreased. Our objective is to describe the effect of lopinavir/ritonavir on tenofovir pharmacokinetics during pregnancy.

Methods

Data were collected through the International Maternal Pediatric and Adolescent AIDS Clinical Trials (IMPAACT) Network P1026s protocol. This was a nonrandomized, open-label, parallel-group and multicentre phase-IV prospective study in pregnant women with HIV. Intensive steady-state 24-h pharmacokinetic profiles were collected during the third trimester of pregnancy and postpartum. Tenofovir was measured in plasma using validated liquid chromatography-mass spectrometry method (quantification limit: 10 ng/ml). Statistical tests compared paired and between group pharmacokinetic data.

Results and discussion

In women not receiving lopinavir/ritonavir (n = 28), tenofovir AUC_0-24 was 27% lower (2.2 mcg·h/ml vs 2.8 mcg·h/ml, p = 0.002) and oral clearance was 27% higher (61 L/h vs 48 L/h, p = 0.001) during the third trimester compared to paired postpartum data. In women receiving lopinavir/ritonavir (n = 10), tenofovir AUC_0-24 and oral clearance were not different antepartum compared to postpartum. Women with and women without concomitant lopinavir/ritonavir displayed no significant differences in postpartum tenofovir pharmacokinetics.

What is new and conclusion

Tenofovir exposure during the third trimester was reduced compared to postpartum in pregnant women not receiving lopinavir/ritonavir, but not in pregnant women also receiving lopinavir/ritonavir. Our findings suggest that pregnancy confounds the expected decrease in tenofovir exposure with concomitant lopinavir/ritonavir in non-pregnant adults. These findings illustrate the need for drug-drug interaction studies in pregnant women as drug disposition differs significantly in pregnant women compared to non-pregnant adults.

Background

This study aims to evaluate the pharmacokinetics of an increased dose of darunavir (800 mg twice daily) with 100 mg ritonavir during pregnancy and postpartum.

Methods

Darunavir (DRV) and ritonavir (RTV; r) intensive pharmacokinetic evaluations were performed at steady state during the second and third trimesters of pregnancy (DRV/r 800/100 mg bid) and 2-3 weeks postpartum (DRV/r 600/100 mg twice daily). Plasma concentrations of darunavir and ritonavir were measured using high-performance liquid chromatography. Target darunavir area under the concentration time curve (AUC) was >70% (43.6 μg × h/mL) of median AUC (62.3 μg × h/mL) in nonpregnant adults on twice daily darunavir-ritonavir 600/100 mg.

Results

Twenty-four women were included in the analysis. Darunavir AUC0-12 was lower with the increased dose during the second {[geometric mean ratio (GMR) of 0.62 (IQR 0.44-0.88); P = 0.055]} and third trimesters [GMR 0.64 (IQR 0.55-0.73); P = <0.001] compared with postpartum. Darunavir apparent clearance was higher during the second [GMR 1.77 (IQR 1.24-2.51); P = 0.039] and third trimesters [GMR 2.01 (IQR 1.17-2.35); P = <0.001] compared with postpartum. Similarly, ritonavir AUC0-12 was lower during the third trimester [GMR 0.65 (IQR 0.52-0.82); P = 0.007] compared with postpartum, whereas its apparent clearance was higher during the third trimester [GMR 1.53 (IQR 1.22-1.92); P = 0.008] compared with postpartum. No major drug-related safety concerns were noted.

Conclusions

Increasing darunavir dose to 800 mg BID failed to significantly increase darunavir exposure compared with 600 mg BID. Other strategies, such as increasing the ritonavir dose should be investigated.

Objective

To evaluate dolutegravir pharmacokinetics during pregnancy compared with postpartum and in infant washout samples after delivery.

Design

Ongoing, nonrandomized, open-label, parallel-group, multicenter phase-IV prospective study of antiretroviral pharmacokinetics in HIV-infected pregnant women and infants.

Methods

Intensive steady-state 24 h pharmacokinetic profiles after dolutegravir 50 mg once-daily were performed during the second trimester (2T), third trimester (3T) and postpartum. Maternal delivery and postnatal infant samples were collected after birth. Dolutegravir was measured by validated LC-MS/MS; quantitation limit was 0.005 μg/ml. A two-tailed Wilcoxon signed-rank test (α = 0.10) was employed for paired within-subject comparisons.

Results

Twenty-nine enrolled participants had a median age of 32 years (range 21-42). Pharmacokinetic data were available for 15 (2T), 28 (3T) and 23 (postpartum) women. Median dolutegravir AUC0-24,Cmax and C24 were 25-51% lower in the 2T and 3T compared with postpartum. The median cord blood/maternal plasma concentration ratio was 1.25 (n = 18). In 21 infants, median elimination half-life was 32.8 h after in utero exposure. Viral load at delivery was less than 50 copies/ml for 27/29 women (93%). Twenty-nine infants were HIV-negative. Renal abnormalities noted on ultrasound in two infants were deemed possibly related to dolutegravir.

Conclusion

Dolutegravir exposure is lower in pregnancy compared with postpartum in the same women on once-daily dosing. Median AUC0-24 during pregnancy was similar to, whereas trough concentrations were lower than, those seen in nonpregnant adults. Trough concentrations in pregnancy were well above dolutegravir EC90 (0.064 μg/ml). Dolutegravir readily crosses the placenta. Infant elimination is prolonged, with half-life over twice that of historical adult controls.

Background

Concentrations of antiretrovirals in the genital tract play a key role in preexposure prophylaxis. This study aims to describe rilpivirine (Edurant) concentrations in the genital tract in pregnant and postpartum women.

Methods

International Maternal Pediatric Adolescent AIDS Clinical Trials Protocol P1026s is an ongoing, prospective study of antiretroviral pharmacokinetics in HIV-infected pregnant women that include a cohort receiving rilpivirine combination regimen. Intensive pharmacokinetics evaluations were performed at steady state during the second and third trimester, and postpartum. Plasma and directly aspirated cervicovaginal fluid (CVF) samples were collected at 4 time points around an observed dose and measured using high-performance liquid chromatography with ultraviolet detection, [plasma; lower limit of quantification (LLQ) = 10 ng/mL] or liquid chromatography-tandem mass spectrometry (CVF; LLQ = 1 ng/mL).

Results

A total of 24 women were included in the analysis. For all time points combined, median (interquartile range) rilpivirine concentrations were 70 ng/mL (23-121) in CVF and 92 ng/mL (49-147) in plasma. The CVF to plasma AUC(0-4) ratios were significantly higher in the second (0.90, 90% CI: 0.61 to 1.46) and third trimesters of pregnancy compared with postpartum (0.40, 90% CI: 0.19 to 0.87). Three of 189 (1.6%) plasma samples in 2 women were below the LLQ and the corresponding CVF concentrations. Seventeen additional CVF concentrations (10.6%) were below LLQ in 13 participants. No major safety concerns were noted.

Conclusions

Rilpivirine concentrations were higher in the CVF during pregnancy compared with postpartum. CVF Rilpivirine is likely to achieve inhibitory concentrations effective for preventing peripartum HIV transmission.

Background

Tenofovir alafenamide (TAF) is a key component of HIV treatment, but pharmacokinetic data supporting the use of TAF during pregnancy are limited. In this study, we report pharmacokinetic, safety, and birth outcomes for TAF 25 mg with a boosted protease inhibitor in pregnant women living with HIV.

Methods

IMPAACT P1026s was a multicenter, nonrandomized, open-label, phase IV prospective study. Pregnant women living with HIV receiving TAF 25 mg with a boosted protease inhibitor were eligible. Intensive pharmacokinetic assessments were performed during the second and third trimesters and 6-12 weeks postpartum. Maternal and cord blood samples were collected at delivery. Infant washout samples were collected through 5-9 days postbirth. Comparisons of paired pharmacokinetic data between pregnancy and postpartum were made using geometric mean ratios (GMR) [90% confidence intervals (CIs)] and Wilcoxon signed-rank tests with P < 0.10 considered significant.

Results

Twenty-nine women were enrolled from the United States (median age 31 years and weight 84.5 kg during the third trimester; 48% Black, 45% Hispanic/Latina). TAF AUCtau did not significantly differ in the second [GMR 0.62 (90% CI: 0.29 to 1.34); P = 0.46] or third trimester [GMR 0.94 (90% CI: 0.63 to 1.39); P = 0.50] vs. postpartum and were comparable with historical data in nonpregnant adults. TAF was only quantifiable in 2/25 maternal delivery samples and below the limit of quantification in all cord blood and infant washout samples, likely because of the short half-life of TAF.

Conclusion

TAF AUCtau did not significantly differ between pregnancy and postpartum. These findings provide reassurance as TAF use during pregnancy continues to expand.

Background

Rilpivirine pharmacokinetics is defined by its absorption, distribution, metabolism, and excretion. Pregnancy can affect these factors by changes in cardiac output, protein binding, volume of distribution, and cytochrome P450 (CYP) 3A4 activity. Rilpivirine is metabolized by CYP3A4. The impact of pregnancy on rilpivirine pharmacokinetics is largely unknown.

Methods

International Maternal Pediatric Adolescent AIDS Clinical Trials P1026s is a multicenter, nonblinded, prospective study evaluating antiretroviral pharmacokinetics in HIV-infected pregnant women that included a cohort receiving rilpivirine 25 mg once daily as part of their combination antiretrovirals for clinical care. Thirty-two women were enrolled in this study. Intensive pharmacokinetic sampling was performed at steady state during the second trimester, the third trimester, and postpartum. Maternal and umbilical cord blood samples were obtained at delivery. Plasma rilpivirine concentration was measured using liquid chromatography-mass spectrometry; lower limit of quantitation was 10 ng/mL.

Results

Median (range) AUC0-24 were 1969 (867-4987, n = 15), 1669 (556-4312, n = 28), and 2387 (188-6736, n = 28) ng·h/mL in the second trimester, the third trimester, and postpartum, respectively (P < 0.05 for either trimester vs postpartum). Median (range) C24 were 63 (37-225, n = 17), 56 (<10-181, n = 30), and 81 (<10-299, n = 28) ng/mL (P < 0.05 for either trimester vs postpartum). High variability in pharmacokinetic parameters was observed between subjects. Median (range) cord blood/maternal concentration ratio was 0.55 (0.3-0.8, n = 21). Delivery HIV-1 RNA was ≤50 copies per milliliter in 70% and ≤400 copies per milliliter in 90% of women. Cmin were significantly lower at 15 visits with detectable HIV-1 RNA compared with 61 visits with undetectable HIV-1 RNA, 29 (<10-93) vs 63 (15-200) ng/mL (P = 0.0001). Cmin was below the protein binding-adjusted EC90 concentration (12.2 ng/mL) at 4 visits in 3 of 31 women (10%).

Conclusions

Rilpivirine exposure is lower during pregnancy compared with postpartum and highly variable. Ninety percent of women had minimum concentrations above the protein binding-adjusted EC90 for rilpivirine.

Objective

To evaluate elvitegravir and cobicistat pharmacokinetics during pregnancy compared with postpartum and in infant washout samples after delivery.

Design

Nonrandomized, open-label, parallel-group, multicenter phase-IV prospective study of antiretroviral pharmacokinetics in HIV-infected pregnant women and their children in the United States.

Methods

Intensive steady-state 24-h pharmacokinetic profiles after 150 mg of elvitegravir and 150 mg of cobicistat given orally in fixed dose combination once-daily were performed during the second trimester, third trimester, and postpartum. Infant washout samples were collected after birth. Elvitegravir and cobicistat were measured in plasma by a validated liquid chromatography with tandem mass spectrometry assay with a lower quantitation limit of 10 ng/ml. A two-tailed Wilcoxon signed-rank test (α = 0.10) was employed for paired within-participant comparisons.

Results

Thirty pregnant women taking elvitegravir and cobicistat once-daily enrolled in the study. Compared with paired postpartum data, elvitegravir AUC0-24 was 24% lower in the second trimester [n = 14, P = 0.058, geometric mean ratios (GMR) = 0.76, 90% confidence interval (CI) 0.57-1.0] and 44% lower in the third trimester (n = 24, P = 0.0001, GMR = 0.56, 90% CI 0.42-0.73), while cobicistat AUC0-24 was 44% lower in the second trimester (n = 14, P = 0.0085, GMR = 0.56, 90% CI 0.37-0.85) and 59% lower in the third trimester (n = 24, P < 0.0001, GMR = 0.41, 90% CI 0.30-0.57). Median cord blood elvitegravir concentration was 540.6 ng/ml and the median ratio of cord blood to maternal plasma elvitegravir concentrations was 0.91.

Conclusion

Standard elvitegravir and cobicistat dosing during pregnancy results in significantly lower exposure which may increase the risk of virologic failure and mother-to-child transmission. Additional studies are needed to optimize elvitegravir and cobicistat dosing regimens in pregnant women.

Background

The study goal was to describe etravirine pharmacokinetics during pregnancy and postpartum in HIV-infected women.

Methods

IMPAACT P1026s and PANNA are on-going, non-randomized, open-label, parallel-group, multi-center phase-IV prospective studies in HIV-infected pregnant women. Intensive steady-state 12-h pharmacokinetic profiles were performed from 2nd trimester through postpartum. Etravirine was measured at two labs using validated ultra performance liquid chromatography (detection limits: 0.020 and 0.026 mcg/mL).

Results

Fifteen women took etravirine 200 mg twice-daily. Etravirine AUC0-12 was higher in the 3rd trimester compared to paired postpartum data by 34% (median 8.3 vs. 5.3 mcg*h/mL, p = 0.068). Etravirine apparent oral clearance was significantly lower in the 3rd trimester of pregnancy compared to paired postpartum data by 52% (median 24 vs. 38 L/h, p = 0.025). The median ratio of cord blood to maternal plasma concentration at delivery was 0.52 (range: 0.19-4.25) and no perinatal transmission occurred.

Conclusion

Etravirine apparent oral clearance is reduced and exposure increased during the third trimester of pregnancy. Based on prior dose-ranging and safety data, no dose adjustment is necessary for maternal health but the effects of etravirine in utero are unknown. Maternal health and infant outcomes should be closely monitored until further infant safety data are available.

Clinical trial registration

The IMPAACT protocol P1026s and PANNA study are registered at ClinicalTrials.gov under NCT00042289 and NCT00825929.

Background

There are limited data on the impact of antenatal antiretroviral regimens (ARV) on pregnancy and infant outcomes in HIV/HBV coinfection. We compared outcomes among 3 antenatal antiretroviral regimens for pregnant women with HIV/HBV.

Methods

The PROMISE study enrolled ARV-naive pregnant women with HIV. Women with HBV were randomized to (no anti-HBV)-zidovudine (ZDV) + intrapartum nevirapine and 1 week of tenofovir disoproxil fumarate and emtricitabine (TDF-FTC); (3TC)-3TC + ZDV + LPV/r; or (FTC-TDF)-FTC + TDF + LPV/r. Pairwise group comparisons were performed with Fisher exact, t , or log rank tests. Adverse pregnancy outcome (APO) was a composite of low birth weight, preterm delivery, spontaneous abortion, stillbirth, or congenital anomaly.

Results

Of 138 women with HIV/HBV, 42, 48, and 48 were analyzed in the no anti-HBV, 3TC, and FTC-TDF arms. Median age was 27 years. APOs trended lower in the no anti-HBV (26%) vs 3TC (38%), and FTC-TDF arms (35%), P ≥ 0.25). More infant deaths occurred among the FTC-TDF [6 (13%)] vs no anti-HBV [2 (5%)] and 3TC [3 (7%)] arms. There were no differences in time-to-death, HIV-free survival, birth or one-year WHO Z-score length-for-age, and head circumference. Hepatitis B e antigen (HBeAg) was associated with an increased risk of APO, 48% vs 27% (odds ratio 2.79, 95% confidence interval: 1.19 to 6.67, post hoc ).

Conclusion

With HBV/HIV coinfection, the risk of an APO was increased with maternal ARV compared with ZDV alone, although the differences were not statistically significant. Maternal HBeAg was associated with a significantly increased risk of APO. Infant mortality was highest with FTC + TDF + LPV/r. Early assessment of HBeAg could assist in identifying high-risk pregnancies for close monitoring.