Use of enhanced perinatal human immunodeficiency virus surveillance methods to assess antiretroviral use and perinatal human immunodeficiency virus transmission in the United States, 1999-2001

Evaluating darunavir/ritonavir dosing regimens for HIV-positive pregnant women using semi-mechanistic pharmacokinetic modelling

BACKGROUND

Darunavir 800 mg once (q24h) or 600 mg twice (q12h) daily combined with low-dose ritonavir is used to treat HIV-positive pregnant women. Decreased total darunavir exposure (17%-50%) has been reported during pregnancy, but limited data on unbound exposure are available.

OBJECTIVES

To evaluate total and unbound darunavir exposures following standard darunavir/ritonavir dosing and to explore the value of potential optimized darunavir/ritonavir dosing regimens for HIV-positive pregnant women.

PATIENTS AND METHODS

A population pharmacokinetic analysis was conducted based on data from 85 women. The final model was used to simulate total and unbound darunavir AUC0-τ and Ctrough during the third trimester of pregnancy, as well as to assess the probability of therapeutic exposure.

RESULTS

Simulations predicted that total darunavir exposure (AUC0-τ) was 24% and 23% lower in pregnancy for standard q24h and q12h dosing, respectively. Unbound darunavir AUC0-τ was 5% and 8% lower compared with post-partum for standard q24h and q12h dosing, respectively. The probability of therapeutic exposure (unbound) during pregnancy was higher for standard q12h dosing (99%) than for q24h dosing (94%).

CONCLUSIONS

The standard q12h regimen resulted in maximal and higher rates of therapeutic exposure compared with standard q24h dosing. Darunavir/ritonavir 600/100 mg q12h should therefore be the preferred regimen during pregnancy unless (adherence) issues dictate q24h dosing. The value of alternative dosing regimens seems limited.

Screening for HIV Infection in Pregnant Women: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Prenatal screening for HIV can inform use of interventions to reduce the risk of mother-to-child transmission. The US Preventive Services Task Force (USPSTF) previously found strong evidence that prenatal HIV screening reduced risk of mother-to-child transmission. The previous evidence review was conducted in 2012.

OBJECTIVE

To update the 2012 review on prenatal HIV screening to inform the USPSTF.

DATA SOURCES

Ovid MEDLINE, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews from 2012 to June 2018, with surveillance through January 2019.

STUDY SELECTION

Pregnant persons 13 years and older; randomized clinical trials and cohort studies of screening vs no screening; risk of mother-to-child transmission or maternal or infant harms associated with antiretroviral therapy (ART) during pregnancy; screening yield at different intervals or in different risk groups.

DATA EXTRACTION AND SYNTHESIS

One investigator abstracted data; a second checked accuracy. Two investigators independently rated study quality.

MAIN OUTCOMES AND MEASURES

Mother-to-child transmission; harms of screening and treatment; screening yield.

RESULTS

Sixty-two studies were included in this review, including 29 new studies. There remains no direct evidence on effects of prenatal screening vs no screening on risk of mother-to-child HIV transmission, maternal or infant clinical outcomes, or the yield of repeat or alternative screening strategies. New evidence confirms that combination ART is highly effective at reducing the risk of mother-to-child transmission, with some new cohort studies reporting rates of mother-to-child transmission less than 1% when combination ART was started early in pregnancy (when begun in first trimester, 0%-0.4%; when begun after first trimester, or at any time if timing of ART initiation not reported, 0.4%-2.8%). New evidence on harms of ART was also largely consistent with the previous review. Evidence from primarily observational studies found prenatal combination ART with a boosted protease inhibitor associated with increased risk of preterm delivery (range, 14.4%-26.1%). For other birth outcomes (low birth weight, small for gestational age, stillbirth, birth defects, neonatal death), results were mixed and depended on the specific antiretroviral drug or drug regimen given and timing of prenatal therapy.

CONCLUSIONS AND RELEVANCE

Combination ART was highly effective at reducing risk of mother-to-child HIV transmission. Use of certain ART regimens during pregnancy was associated with increased risk of harms that may be mitigated by selection of ART regimen. The 2012 review found that avoidance of breastfeeding and cesarean delivery in women with viremia also reduced risk of transmission and that prenatal screening accurately diagnosed HIV infection.

Missed Opportunities for Preventing Perinatal Transmission of Human Immunodeficiency Virus, Florida, 2007-2014

OBJECTIVES

Despite declining numbers of perinatally exposed infants, an increase in perinatal human immunodeficiency virus (HIV) infections from 2011 to 2013 prompted this study to identify missed perinatal HIV prevention opportunities.

METHODS

Deidentified records of children born from 2007 through 2014, exposed to HIV perinatally, and reported to the Florida Department of Health were obtained. Crude relative risks (RRs) and 95% confidence intervals (CIs) for factors associated with perinatal transmission, nondiagnosis of maternal HIV infection, and nonreceipt of antiretroviral medication were calculated.

RESULTS

Of the 4337 known singleton births exposed to maternal HIV infection, 70 (1.6%) were perinatally infected. Among perinatal transmission cases, more than one-third of mothers used illegal drugs or acquired a sexually transmitted infection during pregnancy. Perinatal transmission was most strongly associated with maternal HIV diagnosis during labor and delivery (RR 5.66, 95% CI 2.31-13.91) or after birth (RR 26.50, 95% CI 15.44-45.49) compared with antenatally or prenatally. Among the 29 women whose infection was not known before pregnancy and whose child was perinatally infected, 18 were not diagnosed during pregnancy; 12 had evidence of an acute HIV infection, and 6 had no prenatal care.

CONCLUSIONS

Late diagnosis of maternal HIV infection appeared to be primarily the result of acute maternal infections and inadequate prenatal care. In Florida, effective programs to improve utilization of prenatal care and detection and primary prevention of prenatal acute infection are needed.

Perinatal HIV Exposure Surveillance and Reporting in the United States, 2014

OBJECTIVE

We sought to describe the current status of perinatal HIV exposure surveillance (PHES) activities and regulations in the United States and to make recommendations to strengthen PHES.

METHODS

In 2014, we sent an online survey to health departments in the 50 states, District of Columbia, Puerto Rico, Virgin Islands, and 6 cities and counties (Chicago, Illinois; Houston, Texas; Los Angeles, California; New York, New York; Philadelphia, Pennsylvania; and San Francisco, California). We analyzed responses from 56 of the 59 (95%) jurisdictions.

RESULTS

Thirty-three of 56 jurisdictions (59%) reported conducting PHES and following infants to determine their infection status. Of the 33 jurisdictions performing PHES, 28 (85%) linked maternal and infant data, but only 12 (36%) determined the HIV care status of postpartum women. Themes of respondents' recommendations for strengthening PHES centered on updating laws and regulations to support PHES, reporting all HIV test results and linking vital records with PHES data to identify and follow HIV-exposed infants, communicating with health care providers to improve reporting, training staff, and getting help from experienced jurisdictions to implement PHES.

CONCLUSIONS

Our findings indicate that data on perinatal exposure collected through the current system are inadequate to comprehensively monitor and prevent perinatal HIV exposure and transmission. Comprehensive PHES data collection and reporting are needed to sustain the progress that has been made toward lowering perinatal HIV transmission rates. We propose that minimum standards be established for perinatal HIV exposure reporting to improve the completeness, quality, and efficiency of PHES in the United States.

The pharmacokinetics of abacavir 600 mg once daily in HIV-1-positive pregnant women

OBJECTIVE

To describe the pharmacokinetics of abacavir 600 mg once daily (q.d.) in HIV-1-positive women during pregnancy and postpartum.

DESIGN

A nonrandomized, open-label, multicentre, phase-IV study.

METHODS

HIV-positive pregnant women receiving abacavir 600 mg q.d. as part of clinical care were included. Intensive 24-h pharmacokinetic sampling was performed during the third trimester and at least 2 weeks after delivery. Pharmacokinetic parameters were calculated by noncompartmental analysis. Paired cord blood and maternal blood samples were taken at delivery when feasible.

RESULTS

A total of 14 women were included in the analysis. Geometric mean ratios (90% confidence intervals) of third trimester versus postpartum were 1.05 (0.92-1.19) for AUC0-24h and 1.00 (0.83-1.21) for Cmax. The median (range) ratio of abacavir cord plasma to maternal plasma was 1.0 (0.7-1.0, n = 3). Viral load at the third trimester visit was less than 50 copies/ml in 13 participants (93%; one unknown). In total, 13 (93%; one unknown) children were tested HIV-negative.

CONCLUSION

The pharmacokinetics of abacavir 600 mg q.d. during pregnancy are equivalent to postpartum. No dose adjustments are required during pregnancy and similar antiviral activity is expected.

Maraviroc Pharmacokinetics in HIV-1-Infected Pregnant Women

OBJECTIVE

To describe the pharmacokinetics of maraviroc in human immunodeficiency virus (HIV)-infected women during pregnancy and post partum.

METHODS

HIV-infected pregnant women receiving maraviroc as part of clinical care had intensive steady-state 12-hour pharmacokinetic profiles performed during the third trimester and ≥2 weeks after delivery. Cord blood samples and matching maternal blood samples were taken at delivery. The data were collected in 2 studies: P1026 (United States) and PANNA (Europe). Pharmacokinetic parameters were calculated.

RESULTS

Eighteen women were included in the analysis. Most women (12; 67%) received 150 mg of maraviroc twice daily with a protease inhibitor, 2 (11%) received 300 mg twice daily without a protease inhibitor, and 4 (22%) had an alternative regimen. The geometric mean ratios for third-trimester versus postpartum maraviroc were 0.72 (90% confidence interval, .60-.88) for the area under the curve over a dosing interval (AUCtau) and 0.70 (0.58-0.85) for the maximum maraviroc concentration. Only 1 patient showed a trough concentration (Ctrough) below the suggested target of 50 ng/mL, both during pregnancy and post partum. The median ratio of maraviroc cord blood to maternal blood was 0.33 (range, 0.03-0.56). The viral load close to delivery was <50 copies/mL in 13 women (76%). All children were HIV negative at testing.

CONCLUSIONS

Overall maraviroc exposure during pregnancy was decreased, with a reduction in AUCtau and maximum concentration of about 30%. Ctrough was reduced by 15% but exceeded the minimum Ctrough target concentration. Therefore, the standard adult dose seems sufficient in pregnancy.

CLINICAL TRIALS REGISTRATION

NCT00825929 and NCT000422890.

Placental transfer of the HIV integrase inhibitor dolutegravir in an ex vivo human cotyledon perfusion model

OBJECTIVES

Data on fetal exposure to antiretroviral agents during pregnancy are important to estimate their potential for prevention of mother-to-child transmission (PMTCT) and possible toxicity. For the recently developed HIV integrase inhibitor dolutegravir, clinical data on fetal disposition are not yet available. Dual perfusion of a single placental lobule (cotyledon) provides a useful ex vivo model to predict the in vivo maternal-to-fetal transfer of this drug. The aim of this study was to estimate the transfer of dolutegravir across the human term placenta, using a dual-perfusion cotyledon model.

METHODS

After cannulation of the cotyledons (n = 6), a fetal circulation of 6 mL/min and maternal circulation of 12 mL/min were initiated. The perfusion medium consisted of Krebs-Henseleit buffer (pH = 7.2-7.4) supplemented with 10.1 mM glucose, 30 g/L human serum albumin and 0.5 mL/L heparin 5000IE. Dolutegravir was administered to the maternal circulation (∼ 4.2 mg/L) and analysed by UPLC-MS/MS.

RESULTS

After 3 h of perfusion, the mean ± SD fetal-to-maternal (FTM) concentration ratio of dolutegravir was 0.6 ± 0.2 and the mean ± SD concentrations in the maternal and fetal compartments were 2.3 ± 0.4 and 1.3 ± 0.3 mg/L, respectively.

CONCLUSIONS

Dolutegravir crosses the blood-placental barrier with a mean FTM concentration ratio of 0.6. Compared with other antiretroviral agents, placental transfer of dolutegravir is moderate to high. These data suggest that dolutegravir holds clinical potential for pre-exposure prophylaxis and consequently PMTCT, but also risk of fetal toxicity.

Pharmacokinetics of total and unbound darunavir in HIV-1-infected pregnant women

OBJECTIVES

To describe the pharmacokinetics of darunavir in pregnant HIV-infected women in the third trimester and post-partum.

PATIENTS AND METHODS

This was a non-randomized, open-label, multicentre, Phase IV study in HIV-infected pregnant women recruited from HIV treatment centres in Europe. HIV-infected pregnant women treated with darunavir (800/100 mg once daily or 600/100 mg twice daily) as part of their combination ART were included. Pharmacokinetic curves were recorded in the third trimester and post-partum. A cord blood sample and maternal sample were collected. The study is registered at ClinicalTrials.gov under number NCT00825929.

RESULTS

Twenty-four women were included in the analysis [darunavir/ritonavir: 600/100 mg twice daily (n=6); 800/100 mg once daily (n=17); and 600/100 mg once daily (n=1)]. Geometric mean ratios of third trimester versus post-partum (90% CI) were 0.78 (0.60-1.00) for total darunavir AUC0-tau after 600/100 mg twice-daily dosing and 0.67 (0.56-0.82) for total darunavir AUC0-tau after 800/100 mg once-daily dosing. The unbound fraction of darunavir was not different during pregnancy (12%) compared with post-partum (10%). The median (range) ratio of darunavir cord blood/maternal blood was 0.13 (0.08-0.35). Viral load close to delivery was <300 copies/mL in all but two patients. All children were tested HIV-negative and no congenital abnormalities were reported.

CONCLUSIONS

Darunavir AUC and Cmax were substantially decreased in pregnancy for both darunavir/ritonavir regimens. This decrease in exposure did not result in mother-to-child transmission. For antiretroviral-naive patients, who are adherent, take darunavir with food and are not using concomitant medication reducing darunavir concentrations, 800/100 mg of darunavir/ritonavir once daily is adequate in pregnancy. For all other patients 600/100 mg of darunavir/ritonavir twice daily is recommended during pregnancy.

Atazanavir exposure is effective during pregnancy regardless of tenofovir use

BACKGROUND

We studied the effect of pregnancy on atazanavir pharmacokinetics in the presence and absence of tenofovir.

METHODS

This was a non-randomized, open-label, multicentre Phase IV study in HIV-infected pregnant women recruited from European HIV treatment centres. HIV-infected pregnant women treated with boosted atazanavir (300/100 mg or 400/100 mg atazanavir/ritonavir) as part of their combination antiretroviral therapy (cART) were included in the study. 24 h pharmacokinetic curves were recorded in the third trimester and postpartum. Collection of a cord blood and maternal sample at delivery was optional.

RESULTS

31 patients were included in the analysis, 21/31 patients used tenofovir as part of cART. Median (range) gestational age at delivery was 39 weeks (36-42). Approaching delivery 81% (25 patients) had an HIV viral load <50 copies/ml, all <1,000 copies/ml. Least squares means ratios (90% CI) of atazanavir pharmacokinetic parameters third trimester/postpartum were: 0.66 (0.57, 0.75) for AUC0-24h, 0.70 (0.61, 0.80) for Cmax and 0.59 (0.48, 0.72) for C24h. No statistical difference in pharmacokinetic parameters was found between patients using tenofovir versus no tenofovir. None of the patients showed atazanavir concentrations <0.15 mg/l (target for treatment-naive patients). One baby had a congenital abnormality, which was not likely to be related to atazanavir/ritonavir use. None of the children were HIV-infected.

CONCLUSIONS

Despite 34% lower atazanavir exposure during pregnancy, atazanavir/ritonavir 300/100 mg once daily generates effective concentrations for protease inhibitor (PI)-naive patients, even if co-administered with tenofovir. For treatment-experienced patients (with relevant PI resistance mutations) therapeutic drug monitoring of atazanavir should be considered to adapt the atazanavir/ritonavir dose on an individual basis.
 ClinicalTrials.gov number NCT00825929.

The pharmacokinetics, safety and efficacy of tenofovir and emtricitabine in HIV-1-infected pregnant women

OBJECTIVE

To describe the pharmacokinetics of tenofovir and emtricitabine in the third trimester of pregnant HIV-infected women and at postpartum.

DESIGN

A nonrandomized, open-label, multicentre phase IV study in HIV-infected pregnant women recruited from HIV treatment centres in Europe.

METHODS

HIV-infected pregnant women treated with the nucleotide/nucleoside analogue reverse transcriptase inhibitors (NRTIs) tenofovir disoproxil fumarate (TDF 300 mg; equivalent to 245 mg tenofovir disoproxil) and/or emtricitabine (FTC 200 mg) were included in the study. Twenty-four-hour pharmacokinetic curves were recorded in the third trimester (preferably week 33) and postpartum (preferably week 4-6). Collection of a cord blood sample and maternal sample at delivery was optional. Pharmacokinetic parameters were calculated using WinNonlin software version 5.3. Statistical analysis was conducted using SPSS version 16.0.

RESULTS

Thirty-four women were included in the analysis. Geometric mean ratios of third trimester vs. postpartum [90% confidence interval (CI)] were 0.77 (0.71-0.83) for TDF area under the curve (AUC0-24 h); 0.81 (0.68-0.96) for TDF Cmax and 0.79 (0.70-0.90) for TDF C24 h and 0.75 (0.68-0.82) for FTC AUC0-24 h; and 0.87 (0.77-0.99) for FTC Cmax and 0.77 (0.52-1.12) for FTC C24 h. The viral load close to delivery was less than 200  copies/ml in all but one patient, the average gestational age at delivery was 38 weeks. All children were tested HIV-negative and no congenital abnormalities were reported.

CONCLUSION

Although pharmacokinetic exposure of the NRTIs TDF and FTC during pregnancy is approximately 25% lower, this was not associated with virological failure in this study and did not result in mother-to-child transmission.

Correlates of mother-to-child transmission of HIV in the United States and Puerto Rico

OBJECTIVE

The goal of this study was to examine associations between demographic, behavioral, and clinical variables and mother-to-child HIV transmission in 15 US jurisdictions for birth years 2005 through 2008.

METHODS

The study used Enhanced Perinatal Surveillance system data for HIV-infected women who gave birth to live infants. Multivariable logistic regression was used to assess variables associated with mother-to-child transmission.

RESULTS

Among 8054 births, 179 infants (2.2%) were diagnosed with HIV infection. Half of the births had at least 1 missed prevention opportunity: 74.3% of infected infants, 52.1% of uninfected infants. Among 7757 mother-infant pairs with sufficient data for analysis, the odds of having an HIV-infected infant were higher for women who received late testing or no prenatal antiretroviral medications (odds ratio: 2.5 [95% confidence interval (CI): 1.5-4.0] and 3.5 [95% CI: 2.0-6.4], respectively). The odds for mothers who breastfed were 4.6 times (95% CI: 2.2-9.8) the odds for those who did not breastfeed. The adjusted odds for women with CD4 counts <200 cells per microliter were 2.4 times (95% CI: 1.4-4.2) those for women with CD4 counts ≥500 cells per microliter. The odds for women who abused substances were twice (95% CI: 1.4-2.9) those for women who did not.

CONCLUSIONS

The odds of having an HIV-infected infant were higher among HIV-infected women who were tested late, had no antiretroviral medications, abused substances, breastfed, or had lower CD4 cell counts. Increases in earlier HIV diagnosis, substance abuse treatment, avoidance of breastfeeding, and use of prenatal antiretroviral medications are critical in eliminating perinatal HIV infections in the United States.

The pharmacokinetics, safety and efficacy of boosted saquinavir tablets in HIV type-1-infected pregnant women

Background

Pregnancy affects the pharmacokinetics of most protease inhibitors. Saquinavir, when administered in a tablet formulation, has not been studied extensively in this setting.

Methods

A pharmacokinetic, prospective, multicentre trial of HIV type-1-infected pregnant women treated with saquinavir (500 mg tablets) boosted with ritonavir at a dose of 1,000/100 mg twice daily plus a nucleoside backbone was conducted. Pharmacokinetic curves were recorded for 12 h in the second trimester (week 20 ±2), the third trimester (week 33 ±2) and post-partum (weeks 4–6). Blood was sampled pre-dosing and at 1, 2, 3, 4, 6, 8, 10 and 12 h post-dosing. Pharmacokinetic parameters were calculated using WinNonlin software version 4.1.

Results

A total of 37 women were included in the analysis. Mean (±sd) values for saquinavir area under the curve (AUC0–12h) were 23.47 h•mg/l (11.92) at week 20 ( n=16), 23.65 h•mg/l (9.07) at week 33 ( n=31) and 25.00 h•mg/l (11.81) post-partum ( n=9). There was no significant difference in the saquinavir AUC0–12h when comparing the data during pregnancy and post-partum. Subtherapeutic plasma concentrations of saquinavir (defined as <0.10 mg/l) were not observed throughout the study. No major safety concerns were noted.

Conclusions

Saquinavir exposure in the new tablet formulation generates adequate saquinavir concentrations throughout the course of pregnancy and is safe to use; therefore, no dose adjustment during pregnancy is needed.

Pregnancy outcomes among HIV-infected women undergoing antiretroviral therapy

Background:

The use of antiretroviral drugs (ARV) to prevent mother-to-child HIV transmission (PMTCT) promises to be effective. However, limited data on the adverse effects of ARV among pregnant women and pregnancy outcomes have been reported in clinical practice.

Objectives:

This study aimed to assess adverse effects and outcomes among pregnant HIV-infected women receiving antiretroviral drugs for either antiretroviral therapy (ART) or PMTCT.

Study Design:

This cohort study was at Chonburi Hospital, Thailand, in 2002-2006.

Results:

A total of 246 pregnant HIV-infected women with the median age (range) of 27 (16-41) years were included in this study. ART was initiated in 16.3% for treatment during ANC, 66.7% for PMTCT during ANC, and 17.1% for PMTCT in labor. Adverse effects, especially anemia, were significantly associated with continuing combined ART in pregnancy (p<0.001). 88.9% delivered normal-term neonates. The prevalence of pre-term delivery was 10.2%. Overall, 24 adverse events from 21 pregnant women (8.5%) were noted. A significantly higher prevalence of pre-term delivery was noted in the groups continuing combined ART, or initiating of PMTCT during labor rather than ANC (p=0.02). The incidence of low Apgar scores was 3.6%, and these were associated with initiation of PMTCT during labor (p=0.004).

Conclusion:

Adverse ARV events were more numerous among the pregnant women who needed ART than PMTCT. ANC is beneficial and strongly recommended for all pregnant HIV-infected women for better pregnancy outcomes.

The missing link: documentation of recognized maternal human immunodeficiency virus infection in exposed infant birth records, 24 United States jurisdictions, 1999-2003

Despite substantial improvements, perinatal human immunodeficiency virus (HIV) transmission has not been eliminated in the United States. We examined the extent and contribution of missed communication opportunities between obstetric and pediatric providers who cared for HIV-infected women and their infants. This was a retrospective review of HIV-exposed infants whose data were reported to the Centers for Disease Control and Prevention Enhanced Perinatal Surveillance System from 1999-2003 (n = 8115). For approximately 4% of the HIV-exposed infants whose data were reported to the Enhanced Perinatal Surveillance System between 1999 and 2003, recognized maternal HIV infection was not documented in the exposed infants' birth records. Such infants were at higher risk of not receiving appropriate neonatal antiretroviral prophylaxis (adjusted odds ratio, 37.3; 95% CI, 24.6-56.4) and had increased odds of HIV infection (adjusted odds ratio, 1.7; 95% CI, 1.1-2.6). Enhanced communication between pediatric and obstetric and gynecologic providers to eliminate this missed opportunity for prevention would improve HIV infection outcomes for HIV-exposed infants and improve care for their mothers.