Nahida Chakhtoura

Bridging Knowledge Gaps to Understand How Zika Virus Exposure and Infection Affect Child Development

Importance The Zika virus (ZIKV) epidemic has profoundly affected the lives of children and families across the Americas. As the number of children born with ZIKV-related complications continues to grow, the long-term developmental trajectory for these children and the effect on their families remains largely unknown. In September 2016, the Eunice Kennedy Shriver National Institute of Child Health and Human Development and partner National Institutes of Health institutes convened a workshop to develop a research agenda to improve the evaluation, monitoring, and management of neonates, infants, or children affected by ZIKV and its complications. The agenda also aims to optimally address the prospective effect of ZIKV exposure on the developing child. Observations The full clinical spectrum of congenital ZIKV syndrome has yet to be elucidated. In addition to the well-described anatomic and neurologic manifestations, clinicians are now describing infants with exaggerated primitive reflexes, epilepsy, acquired hydrocephalus and microcephaly, neurodevelopmental delay, gastrointestinal motility problems, and respiratory complications, such as pneumonia. While we are still learning more about the myriad clinical presentations in these severely affected children, it is also paramount to address the larger proportion of ZIKV-exposed infants who are asymptomatic at birth but, we assume, may develop problems later in life. The available evidence for neurologic, neurodevelopmental, neurobehavioral, auditory, and vision assessments and management for infants with congenital ZIKV syndrome was critically evaluated. Lessons from other congenital infections provide valuable clues about the complexities of management and the optimal approaches for evaluating, treating, and caring for the children, which include engaging and involving parents and caregivers in their treatment. Conclusions and Relevance Rigorous research is key to improving the identification of ZIKV-infected mothers and babies. Research also is critical to increasing basic understanding of the neuropathogenesis of congenital ZIKV disease and of the spectrum of clinical presentations of ZIKV infection so that agents to prevent and treat this devastating disease can be rapidly developed and studied.

Pharmacokinetics of Rilpivirine in HIV-Infected Pregnant Women.

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.

Etravirine pharmacokinetics in HIV-infected 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.

Randomized trial of stopping or continuing ART among postpartum women with pre-ART CD4 ≥ 400 cells/mm3

Background Health benefits of postpartum antiretroviral therapy (ART) for human immunodeficiency virus (HIV) positive women with high CD4+ T-counts have not been assessed in randomized trials. Methods Asymptomatic, HIV-positive, non-breastfeeding women with pre-ART CD4+ T-cell counts ≥ 400 cells/mm3 started on ART during pregnancy were randomized up to 42 days after delivery to continue or discontinue ART. Lopinavir/ritonavir plus tenofovir/emtricitabine was the preferred ART regimen. The sample size was selected to provide 88% power to detect a 50% reduction from an annualized primary event rate of 2.07%. A post-hoc analysis evaluated HIV/AIDS-related and World Health Organization (WHO) Stage 2 and 3 events. All analyses were intent to treat. Results 1652 women from 52 sites in Argentina, Botswana, Brazil, China, Haiti, Peru, Thailand and the US were enrolled (1/2010-11/2014). Median age was 28 years and major racial categories were Black African (28%), Asian (25%) White (15%). Median entry CD4 count was 696 cells/mm3 (IQR 575–869), median ART exposure prior to delivery was 19 weeks (IQR 13–24) and 94% had entry HIV-1 RNA < 1000 copies/ml. After a median follow-up of 2.3 years, the primary composite endpoint rate was significantly lower than expected, and not significantly different between arms (continue arm 0.21 /100 person years(py); discontinue 0.31/100 py, Hazard ratio (HR) 0.68, 95% CI: 0.19, 2.40). WHO Stage 2 and 3 events were significantly reduced with continued ART (2.08/100 py vs. 4.36/100 py in the discontinue arm; HR 0.48, 95%CI: 0.33, 0.70). Toxicity rates did not differ significantly between arms. Among women randomized to continue ART, 189/827 (23%) had virologic failure; of the 155 with resistance testing, 103 (66%) failed without resistance to their current regimen, suggesting non-adherence. Conclusions Overall, serious clinical events were rare among young HIV-positive post-partum women with high CD4 cell counts. Continued ART was safe and was associated with a halving of the rate of WHO 2/3 conditions. Virologic failure rates were high, underscoring the urgent need to improve adherence in this population. Trial registration ClinicalTrials.gov NCT00955968

Management of stillbirth delivery

Stillbirth is a common adverse outcome of pregnancy. Management should be individualized based on gestational age, maternal condition, prior uterine surgery, availability of skilled professionals, and maternal desires. This article discusses available data on management by gestational age and prior uterine surgery. Expectant management is a viable option for women and families who desire it and do not have any contraindications. In the second trimester, misoprostol induction and dilatation and evacuation are effective in the evacuation of the uterus. In the third trimester, induction of labor with prostaglandins, mechanical dilators, and augmentation with oxytocin is appropriate. Care should be taken with women with prior cesarean delivery; prostaglandins ideally should be avoided. Delivery by cesarean section should be performed selectively, i.e., when there is a maternal indication.

Adverse Pregnancy Outcomes Among Women Who Conceive on Antiretroviral Therapy

Background Adverse pregnancy outcomes for women who conceive on antiretroviral therapy (ART) may be increased, but data are conflicting. Methods Human immunodeficiency virus-infected, nonbreastfeeding women with pre-ART CD4 counts ≥400 cells/μL who started ART during pregnancy were randomized after delivery to continue ART (CTART) or discontinue ART (DCART). Women randomized to DCART were recommended to restart if a subsequent pregnancy occurred or for clinical indications. Using both intent-to-treat and as-treated approaches, we performed Fisher exact tests to compare subsequent pregnancy outcomes by randomized arm. Results Subsequent pregnancies occurred in 277 of 1652 (17%) women (CTART: 144/827; DCART: 133/825). A pregnancy outcome was recorded for 266 (96%) women with a median age of 27 years (interquartile range [IQR], 24-31 years) and median CD4+ T-cell count 638 cells/μL (IQR, 492-833 cells/μL). When spontaneous abortions and stillbirths were combined, there was a significant difference in events, with 33 of 140 (23.6%) in the CTART arm and 15 of 126 (11.9%) in the DCART arm (relative risk [RR], 2.0 [95% confidence interval {CI}, 1.1-3.5]; P = .02). In the as-treated analysis, the RR was reduced and no longer statistically significant (RR, 1.4 [95% CI, .8-2.4]). Conclusions Women randomized to continue ART who subsequently conceived were more likely to have spontaneous abortion or stillbirth, compared with women randomized to stop ART; however, the findings did not remain significant in the as-treated analysis. More data are needed on pregnancy outcomes among women conceiving on ART, particularly with newer regimens.

Prevention of Hiv-1 Transmission Through Breastfeeding: Efficacy and Safety of Maternal Antiretroviral Therapy Versus Infant Nevirapine Prophylaxis for Duration of Breastfeeding in Hiv-1-infected Women with High Cd4 Cell Count (impaact Promise)

Background: No randomized trial has directly compared the efficacy of prolonged infant antiretroviral prophylaxis versus maternal antiretroviral therapy (mART) for prevention of mother-to-child transmission throughout the breastfeeding period. Setting: Fourteen sites in Sub-Saharan Africa and India. Methods: A randomized, open-label strategy trial was conducted in HIV-1–infected women with CD4 counts ≥350 cells/mm3 (or ≥country-specific ART threshold if higher) and their breastfeeding HIV-1–uninfected newborns. Randomization at 6–14 days postpartum was to mART or infant nevirapine (iNVP) prophylaxis continued until 18 months after delivery or breastfeeding cessation, infant HIV-1 infection, or toxicity, whichever occurred first. The primary efficacy outcome was confirmed infant HIV-1 infection. Efficacy analyses included all randomized mother–infant pairs except those with infant HIV-1 infection at entry. Results: Between June 2011 and October 2014, 2431 mother–infant pairs were enrolled; 97% of women were World Health Organization Clinical Stage I, median screening CD4 count 686 cells/mm3. Median infant gestational age/birth weight was 39 weeks/2.9 kilograms. Seven of 1219 (0.57%) and 7 of 1211 (0.58%) analyzed infants in the mART and iNVP arms, respectively, were HIV-infected (hazard ratio 1.0, 96% repeated confidence interval 0.3–3.1); infant HIV-free survival was high (97.1%, mART and 97.7%, iNVP, at 24 months). There were no significant differences between arms in median time to breastfeeding cessation (16 months) or incidence of severe, life-threatening, or fatal adverse events for mothers or infants (14 and 42 per 100 person-years, respectively). Conclusions: Both mART and iNVP prophylaxis strategies were safe and associated with very low breastfeeding HIV-1 transmission and high infant HIV-1–free survival at 24 months.