Lamivudine-zidovudine combination for prevention of maternal-infant transmission of HIV-1

Towards complete eradication of hepatitis B infection from perinatal transmission: review of the mechanisms of in utero infection and the use of antiviral treatment during pregnancy

Hepatitis B infection remains the most common form of chronic hepatitis. Mother to child transmission occurs despite immunoprophylaxis with vaccination and immunoglobulin. In utero infection is suggested to account for most of the cases with immunoprophylaxis failure. Infants who suffer from hepatitis B infection at birth have a higher risk of becoming chronic carriers and may develop liver cirrhosis or hepatocellular carcinoma in the future. Infected germ cells, transplacental infection, invasive prenatal diagnostic tests and various perinatal factors are possible factors leading to in utero infection and subsequent immunoprophylaxis failure. Hepatitis B e antigen positive status and high viral load increase the risk of immunoprophylaxis failure. Recent evidence shows promising results regarding the use of antiviral treatment in late gestation to suppress viral load, so as to decrease the risk of vertical transmission. This review discusses the possible mechanisms of in utero infection and the use of antiviral treatment during pregnancy.

Non-disclosure of a pregnant woman's HIV status to her partner is associated with non-optimal prevention of mother-to-child transmission

Our objective was to study relations between non-disclosure of HIV to partner, socio demographics and prevention of HIV mother-to-child transmission (PMTCT), among HIV-infected pregnant women enrolled in the French Perinatal Cohort (ANRS-EPF-CO1) from 2005 to 2009 (N = 2,952). Fifteen percent of the women did not disclose their HIV status to their partner. Non-disclosure was more frequent in women diagnosed with HIV infection late in pregnancy, originating from Sub-Saharan Africa or living alone, as well as when the partner was not tested for HIV. Non-disclosure was independently associated with non optimal PMTCT: late initiation of antiretroviral therapy, detectable viral load at delivery and lack of neonatal prophylaxis. Nonetheless, the rate of transmission did not differ according to disclosure status. Factors associated with non-disclosure reflect vulnerability and its association with non optimal PMTCT is a cause for concern although the impact on transmission was limited in this context of universal free access to care.

Developmental pharmacokinetic changes of Lamivudine in infants and children

Lamivudine is a nucleoside reverse transcriptase inhibitor widely used in infants and children in combination antiretroviral therapy to treat human immunodeficiency virus (HIV) infection. Developmental changes in lamivudine pharmacokinetic disposition were assessed by combining data from 7 studies of lamivudine (Pediatric AIDS Clinical Trials Group 300, 353, 356, 358, 386, 1056, and 1069) representing subjects across the pediatric age continuum. A population pharmacokinetic model was developed to identify factors that influence lamivudine disposition. Age and Thai race were independent predictors of apparent clearance (CL/F), whereas the use of a fixed drug combination formulation (GPO-VIR) was an independent predictor of bioavailability, with CL/F more than doubling from birth to adolescence. Serum creatinine was not associated with CL/F. Monte Carlo simulations were used to compare the lamivudine exposure achieved with World Health Organization (WHO) weight band and Food and Drug Administration (FDA) label dosing recommendations. WHO dosing yielded higher exposure during the first few months of life, but this difference was less pronounced between 6 months and 14 years of age. Overall, both FDA and WHO dosing provided similar AUC values to those previously reported in HIV-infected adults. Lamivudine WHO weight band dosing results in therapeutic exposure in infants and children and may improve drug dosing in resource-limited countries.

Memory CD4+CCR5+ T cells are abundantly present in the gut of newborn infants to facilitate mother-to-child transmission of HIV-1

Despite potential clinical importance, target cells for mother-to-child transmission of HIV-1 have not yet been identified. Cord blood–derived CD4+ T cells are largely naive and do not express CCR5, the mandatory coreceptor for transmitted HIV-1 R5 strains in infants. In the present study, we demonstrate that in the human fetal and infant gut mucosa, there is already a large subset of mucosal memory CD4+CCR5+ T cells with predominantly a Th1 and Th17 phenotype. Using next-generation sequencing of the TCRβ chain, clonally expanded T cells as a hallmark for memory development predominated in the gut mucosa (30%), whereas few were found in the lymph nodes (1%) and none in cord blood (0%). The gut mucosal fetal and infant CD4+ T cells were highly susceptible to HIV-1 without any prestimulation; pol proviral DNA levels were similar to infected phytohemagglutinin-stimulated adult PBMCs. In conclusion, in the present study, we show that extensive adaptive immunity is present before birth and the gut mucosa is the preferential site for memory CD4+ T cells. These CD4+CCR5+ T cells in the infant mucosa provide a large pool of susceptible cells for ingested HIV-1 at birth and during breastfeeding, indicating a mucosal route of mother-to-child transmission that can be targeted in prevention strategies.

Prevention of mother-to-child transmission, drug resistance, and implications for response to therapy

PURPOSE OF REVIEW

HIV-1 drug resistance can emerge in both maternal and infant virus after exposure to antiretroviral drugs for the prevention of mother-to-child transmission of HIV. The purpose of this review is to discuss the prevalence and clinical implications (for antiretroviral treatment outcomes) of this drug resistance, focusing on more recent information.

RECENT FINDINGS

New, highly sensitive laboratory assays have been developed that demonstrate even greater than previously known levels of drug resistance in minor HIV-1 variants after the use of single-dose nevirapine. At the same time, new data related to virological and immunological outcomes among women and infants after exposure to short-course prevention of mother-to-child transmission regimens suggest that although the response to nevirapine-based antiretroviral therapy after single-dose nevirapine may be compromised, this is less of a problem among women starting antiretroviral therapy more remotely from nevirapine exposure.

SUMMARY

Whereas single-dose nevirapine alone should be reserved for settings in which other combination antiretroviral interventions are not feasible for the prevention of mother-to-child transmission, recent data provide measured reassurance to women regarding their future response to nevirapine-containing antiretroviral therapy.

Three postpartum antiretroviral regimens to prevent intrapartum HIV infection

BACKGROUND

The safety and efficacy of adding antiretroviral drugs to standard zidovudine prophylaxis in infants of mothers with human immunodeficiency virus (HIV) infection who did not receive antenatal antiretroviral therapy (ART) because of late identification are unclear. We evaluated three ART regimens in such infants.

METHODS

Within 48 hours after their birth, we randomly assigned formula-fed infants born to women with a peripartum diagnosis of HIV type 1 (HIV-1) infection to one of three regimens: zidovudine for 6 weeks (zidovudine-alone group), zidovudine for 6 weeks plus three doses of nevirapine during the first 8 days of life (two-drug group), or zidovudine for 6 weeks plus nelfinavir and lamivudine for 2 weeks (three-drug group). The primary outcome was HIV-1 infection at 3 months in infants uninfected at birth.

RESULTS

A total of 1684 infants were enrolled in the Americas and South Africa (566 in the zidovudine-alone group, 562 in the two-drug group, and 556 in the three-drug group). The overall rate of in utero transmission of HIV-1 on the basis of Kaplan-Meier estimates was 5.7% (93 infants), with no significant differences among the groups. Intrapartum transmission occurred in 24 infants in the zidovudine-alone group (4.8%; 95% confidence interval [CI], 3.2 to 7.1), as compared with 11 infants in the two-drug group (2.2%; 95% CI, 1.2 to 3.9; P=0.046) and 12 in the three-drug group (2.4%; 95% CI, 1.4 to 4.3; P=0.046). The overall transmission rate was 8.5% (140 infants), with an increased rate in the zidovudine-alone group (P=0.03 for the comparisons with the two- and three-drug groups). On multivariate analysis, zidovudine monotherapy, a higher maternal viral load, and maternal use of illegal substances were significantly associated with transmission. The rate of neutropenia was significantly increased in the three-drug group (P<0.001 for both comparisons with the other groups).

CONCLUSIONS

In neonates whose mothers did not receive ART during pregnancy, prophylaxis with a two- or three-drug ART regimen is superior to zidovudine alone for the prevention of intrapartum HIV transmission; the two-drug regimen has less toxicity than the three-drug regimen. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development [NICHD] and others; ClinicalTrials.gov number, NCT00099359.).

Optimal Management of the Hepatitis B Patient Who Desires Pregnancy or Is Pregnant

Women of childbearing age with recognized hepatitis B infection should have their liver disease assessed before pregnancy occurs since the management of hepatitis B virus (HBV) infection in this setting is complex. Initiation of treatment in a woman of child-bearing age will depend on when she intends on conceiving, as well as the severity of her liver disease. During pregnancy, all decisions about initiating, continuing or stopping HBV therapy must include an analysis of the risks and benefits for both mother and fetus. The trimester of the pregnancy and the stage of the mother's liver disease are important factors. Treatment in the third trimester may be considered to aid in prevention of perinatal transmission, which appears to be most pronounced in mothers with high viral loads. Consideration of initiation of third trimester treatment should occur after a high viral load is documented in the latter part of the second trimester, to allow adequate time for initiation of antiviral therapy with significant viral suppression before delivery. This discussion should include the topic of breastfeeding, since it is generally not recommended while on antiviral therapy. Until recently lamivudine and tenofovir appeared to be the therapeutic options with the most reasonable safety data in pregnancy. There are emerging data that telbivudine may also be considered in this setting.

Chronic hepatitis B infection and pregnancy

It is estimated that 350 to 400 million individuals worldwide are chronically infected with hepatitis B virus (HBV). In regions of high endemicity, many of these are females of reproductive age who are an important source for perinatal transmission. There are a number of issues specific to the women of childbearing age who have chronic HBV infection, including the safety of antiviral therapy during pregnancy and breast-feeding, the changes in the immune system during pregnancy and postpartum that may impact on the natural history of HBV, and the emerging role of antivirals to reduce perinatal transmission of HBV. For women in their reproductive years who require treatment, many of the available antivirals have not been studied in pregnant or breast-feeding women and their use requires the development of a carefully considered strategy, considering the impact of both the disease and treatment on the mother and fetus/infant. The purpose of this article is to (1) review data regarding the mechanisms and timing of perinatal HBV infection; (2) review data on interventions, particularly antiviral therapy, to reduce perinatal transmission beyond the protection afforded by hepatitis B immunoglobulin and vaccination; (3) summarize the immunological changes associated with pregnancy and the potential effect these may have on the natural history of HBV infection; and (4) summarize the information currently available for antiviral therapy available for HBV treatment, focusing specifically on safety data pertaining to reproduction, pregnancy, and breast-feeding.

TARGET AUDIENCE

Obstetricians & Gynecologists and Family Physicians.

LEARNING OBJECTIVES

After completing this CME activity physicians should be better able to classify the interventions to reduce mother-to-child transmission of hepatitis B including antivirals, caesarean section, hepatitis B immunoglobulin and hepatitis B vaccine, assess the immunological changes associated with pregnancy and the potential effect this may have on the natural history of HBV infection and apply the information currently available for antiviral therapy licensed for HBV treatment, focusing specifically on safety data in pregnancy and during breastfeeding.

Prevalence of congenital anomalies in infants with in utero exposure to antiretrovirals

BACKGROUND

Although use of efficacious interventions, including antiretrovirals (ARVs), has dramatically reduced the rate of mother-to-child transmission of human immunodeficiency virus, the safety of in utero ARV exposure remains of concern.

METHODS

Data regarding 1112 infants enrolled in the International Maternal Pediatric Adolescent AIDS Clinical Trials Group protocol P1025 born between 2002 and 2007 were analyzed for this study. Congenital anomalies were classified based on the Metropolitan Atlanta Congenital Defects Program guidelines. Associations between congenital anomalies and timing of first in utero exposure to ARVs were evaluated by logistic regression analysis.

RESULTS

Congenital anomalies were identified and confirmed in 61 of the 1112 infants, resulting in a prevalence of 5.49/100 live births (95% confidence interval, 4.22-6.99). Among the 80 anomalies identified, the organ systems involved included cardiovascular (n = 33), musculoskeletal (n = 15), renal (n = 9), genitourinary (n = 6), craniofacial (n = 4), and central nervous system (n = 2). First trimester exposure to efavirenz was associated with a significantly increased risk of congenital anomalies (odds ratio, 2.84; 95% confidence interval, 1.13-7.16). No significant associations were observed between exposure to other individual ARVs or classes of ARVs started at any time during pregnancy and infant congenital anomalies.

CONCLUSIONS

The observed rate of congenital anomalies in this cohort is higher than previously reported for the general population, but it is consistent with rates observed in other recent studies of children born to human immunodeficiency virus-infected women. Cardiovascular anomalies occurred most frequently. With the exception of a known teratogen (efavirenz), no statistically significant associations between in utero exposure to ARVs and congenital anomalies were identified.

Role of non-nucleoside reverse transcriptase inhibitors in treating HIV-infected children

The first-generation non-nucleoside reverse transcriptase inhibitors (NNRTIs), efavirenz and nevirapine, fulfil key roles in antiretroviral therapy for HIV-infected paediatric patients, from lowering the incidence of mother-to-child transmission during pregnancy and birth to treatment throughout childhood and adolescence. Both agents have established efficacy, safety and tolerability profiles, and also offer advantages over other classes of therapy in terms of regimen simplicity and availability across different treatment settings. Although the role of NNRTIs in paediatric treatment strategies is largely determined by experience in adult patients, results of the recent phase II/III PENPACT-1 trial in infants and children aged between 30 days and 18 years have shown that there are no significant differences in 4-year virological, immunological or clinical outcomes between NNRTIs and protease inhibitors as first- and second-line agents. However, results from the IMPAACT P1060 study (cohort 2), conducted in resource-limited settings, showed that infants under 36 months unexposed to NNRTIs were significantly more likely to fail treatment when started on a nevirapine-based regimen than those on a lopinavir/ritonavir-based regimen. Unfortunately, the use of efavirenz and nevirapine in children can be limited by rapid development of high-level resistance to one or both agents, which may reduce the availability of viable treatment options, particularly in resource-limited settings. Several therapeutic strategies addressing this issue are currently under investigation, but a significant need for new NNRTI-based treatment options remains. The more recently approved NNRTI, etravirine, has demonstrated efficacy and safety benefits in HIV-1-infected, NNRTI-resistant adult patients, with a higher genetic barrier to the development of resistance relative to the first-generation NNRTIs. Another NNRTI, rilpivirine (TMC278), is approved for use in HIV-1-infected, treatment-naïve adult patients and has demonstrated an improved tolerability profile compared with efavirenz. Although available data on etravirine in children are currently limited, ongoing trials will provide important information on the potential for their use in novel paediatric treatment strategies. This review examines the role of efavirenz and nevirapine in paediatric antiretroviral therapy in children within different treatment settings. In addition, this review also outlines available clinical data on etravirine and rilpivirine in the context of how these antiretrovirals may address some of the limitations of efavirenz and nevirapine in paediatric patients.

A comparison of 3 regimens to prevent nevirapine resistance mutations in HIV-infected pregnant women receiving a single intrapartum dose of nevirapine

BACKGROUND

Intrapartum single-dose (SD) nevirapine (NVP) reduces perinatal transmission of human immunodeficiency virus (HIV) infection but selects for NVP-resistant virus, which compromises subsequent NVP-based therapy. A 1-week "tail" of lamivudine and zidovudine after SD-NVP decreases the risk of resistance. We hypothesized that increasing the duration or potency of the tail would further reduce this risk to <10%, using a sensitive assay to measure resistance.

METHODS

HIV-infected pregnant Thai women with a CD4 cell count >250 cells/μL, most receiving zidovudine, were randomized at 28-38 weeks gestation to receive 1 of 3 intrapartum and postpartum regimens: (A) zidovudine plus enteric-coated didanosine plus lopinavir and ritonavir for 7 days, (B) zidovudine plus enteric-coated didanosine for 30 days, or (C) regimen 1 for 30 days. The incidence of NVP resistance mutations at day 10 or week 6 post partum in each arm was compared with that of a historical comparison group who received prenatal zidovudine and SD-NVP. NVP resistance was identified by consensus sequencing and a sensitive oligonucleotide ligation assay (OLA).

RESULTS

At entry, the 169 participants had a median CD4 cell count of 456 cells/μL and an HIV load of 3.49 log(10) copies/mL. The incidence of mutations in each of the 3 P1032 arms was 0% by sequencing and 1.8%, 7.1%, and 5.3% by OLA in arms A, B, and C, respectively, compared with 13.4% by sequencing and 29.4% by OLA in the comparison group (P < .001 for each study arm vs comparison group). Grade 4 anemia developed in 1 woman.

CONCLUSIONS

A 7-day tail of highly active combination therapy or 1 month of dual therapy after SD-NVP prevents most NVP resistance to minimal toxicity.

CLINICAL TRIALS REGISTRATION

The IMPAACT P1032 Clinical Trial is NCT00109590, and the PHPT-2 Clinical Trial is NCT00398684.

Human immunodeficiency virus type 1 mother-to-child transmission and prevention: successes and controversies

The World Health Organization (WHO) and United Nations Programme on HIV/AIDS (UNAIDS) estimated that an additional 370 000 new human immunodeficiency virus type 1 (HIV-1) infections occurred in children in 2009, mainly through mother-to-child transmission (MTCT). Intrapartum transmission contributes to approximately 20-25% of infections, in utero transmission to 5-10% and postnatal transmission to an additional 10-15% of cases. MTCT accounts for only a few hundred infected newborns in those countries in which services are established for voluntary counselling and testing of pregnant women, and a supply of antiretroviral drugs is available throughout pregnancy with recommendations for elective Caesarean section and avoidance of breastfeeding. The single-dose nevirapine regimen has provided the momentum to initiate MTCT programmes in many resource-limited countries; however, regimens using a combination of antiretroviral drugs are needed also to effectively reduce transmission via breastfeeding.

Antiretroviral drugs for preventing mother-to-child transmission of HIV: a review of potential effects on HIV-exposed but uninfected children

The provision of antiretroviral drugs for the prevention of mother-to-child HIV transmission has been rising sharply in low- and middle-income countries. Changes to the World Health Organization guidelines support further extension of these programs. The result will be a greatly expanded population of HIV-exposed but uninfected children with substantial exposure to antiretroviral drugs, both in utero and while breastfeeding. There are limited data on possible toxicities in this burgeoning population, and the large number of confounding factors limits any conclusions. Although the evidence on birth defects and mitochondrial toxicity remains equivocal, considerable data link protease inhibitors to preterm delivery and low birth-weight. Transient hematologic toxicities are also likely. The drug impact later in life is an open question. Larger and longer cohort studies are necessary to properly balance the risks and benefits of large-scale infant exposure to antiretroviral agents.

Previous antiretroviral therapy for prevention of mother-to-child transmission of HIV does not hamper the initial response to PI-based multitherapy during subsequent pregnancy

BACKGROUND

Few data are available on the possible long-term negative effects of a short exposure to antiretroviral therapy (ART) for prevention of mother-to-child transmission (PMTCT).

OBJECTIVE

To determine whether ART for PMTCT, discontinued after delivery, affects the virological response to highly active antiretroviral therapy (HAART) administered during subsequent pregnancies.

METHODS

All current pregnancies of HIV-1-infected women enrolled in the French Perinatal Cohort (ANRS CO-01 EPF) between 2005 and 2009 and not receiving ART at the time of conception were eligible. We studied the association between history of exposure to ART during a previous pregnancy and detectable viral load (VL) under multitherapy at current delivery (VL ≥ 50 copies/mL).

RESULTS

Among 1116 eligible women, 869 were ART naive and 247 had received PMTCT during a previous pregnancy. Previous ART was protease inhibitor (PI)-based HAART in 48%, non-PI-based HAART in 4%, nucleoside reverse transcriptase inhibitor bitherapy in 19% and zidovudine monotherapy in 29% of the women. At current pregnancy, women with or without prior exposure to ART had similar CD4 cell counts and VL before ART initiation. PI-based HAART was initiated in 90% of the women. VL was undetectable (<50 copies/mL) at delivery in 65% of previously ART-naive women, 72% of women previously exposed to HAART, 62% previously exposed to bitherapy, and 67% previously exposed to monotherapy for prophylaxis (P = 0.42). Detectable VL was not associated with previous exposure in multivariate analysis (adjusted OR for previous versus no previous exposure to ART: 0.92; 0.95% confidence interval: 0.59 to 1.44).

CONCLUSIONS

Efficacy of PI-based combinations is not decreased in women previously exposed to various regimens of antiretroviral PMTCT.

Antiretrovirals for reducing the risk of mother-to-child transmission of HIV infection

BACKGROUND

Antiretroviral drugs reduce viral replication and can reduce mother-to-child transmission of HIV either by lowering plasma viral load in pregnant women or through post-exposure prophylaxis in their newborns. In rich countries, highly active antiretroviral therapy (HAART) which usually comprises three drugs, has reduced the mother-to-child transmission rates to around 1-2%, but HAART is not always available in low- and middle-income countries. In these countries, various simpler and less costly antiretroviral regimens have been offered to pregnant women or to their newborn babies, or to both.

OBJECTIVES

To determine whether, and to what extent, antiretroviral regimens aimed at decreasing the risk of mother-to-child transmission of HIV infection achieve a clinically useful decrease in transmission risk, and what effect these interventions have on maternal and infant mortality and morbidity.

SEARCH STRATEGY

We sought to identify all relevant studies regardless of language or publication status by searching the Cochrane HIV/AIDS Review Group Trials Register, The Cochrane Library, MEDLINE, EMBASE and AIDSearch and relevant conference abstracts. We also contacted research organizations and experts in the field for unpublished and ongoing studies. The original review search strategy was conducted in 2002 and updated in 2006 and again in 2009.

SELECTION CRITERIA

Randomised controlled trials of any antiretroviral regimen aimed at decreasing the risk of mother-to-child transmission of HIV infection compared with placebo or no treatment, or compared with another antiretroviral regimen.

DATA COLLECTION AND ANALYSIS

Two authors independently selected relevant studies, extracted data and assessed trial quality. For the primary outcomes, we used survival analysis to estimate the probability of infants being infected with HIV (the observed proportion) at various specific time-points and calculated efficacy at a specific time as the relative reduction in the proportion infected. Efficacy, at a specific time, is defined as the preventive fraction in the exposed group compared to the reference group, which is the relative reduction in the proportion infected: 1-(Re/Rf). For those studies where efficacy and hence confidence intervals were not calculated, we calculated the approximate confidence intervals for the efficacy using recommended methods. For analysis of results that are not based on survival analyses we present the relative risk for each trial outcome based on the number randomised. No meta-analysis was conducted as no trial assessed identical drug regimens.

MAIN RESULTS

Twenty-five trials including 18,901 participants with a median trial sample size of 627 ranging from 50 to 1,844 participants were included in this update. Twenty-two trials randomised mothers (18 pre-natally and four in labour) and followed up their infants, and three trials randomised infants. The first trial began in April 1991 and assessed zidovudine (ZDV) versus placebo and since then, the type, dosage and duration of drugs to be compared has been modified in each subsequent trial. We present the results stratified by regimen and type of feeding.Antiretrovirals versus placebo In breastfeeding populations, three trials found that:ZDV given to mothers from 36 to 38 weeks gestation, during labour and for 7 days after delivery significantly reduced HIV infection at 4-8 weeks (Efficacy 32.00%; 95% CI 1.50 to 62.50), 3 to 4 months (Efficacy 33.07%; 95% CI 5.57 to 60.57), 6 months (Efficacy 34.55%; 95% CI 9.05 to 60.05), 12 months (Efficacy 34.31%; 95% CI 9.30 to 59.32) and 18 months (Efficacy 29.74%; 95% CI 2.73 to 56.75).ZDV given to mothers from 36 weeks gestation and during labour significantly reduced HIV infection at 4 to 8 weeks (Efficacy 43.78%; 95% CI 8.78 to 78.78) and 3 to 4 months (Efficacy 36.95%; 95% CI 2.94 to 70.96) but not at birth.ZDV plus lamivudine (3TC) given to mothers from 36 weeks gestation, during labour and for 7 days after delivery and to babies for the first 7 days after birth (PETRA 'regimen A') significantly reduced HIV infection (Efficacy 62.75%; 95% CI 40.76 to 84.74) and a combined endpoint of HIV infection or death (Efficacy 62.75 [, ]61.00%; 95% CI 40.76 to 84.74) at 4 to 8 weeks but these effects were not sustained at 18 months.ZDV plus 3TC given to mothers from the start of labour until 7 days after delivery and to babies for the first 7 days after birth (PETRA 'regimen B') significantly reduced HIV infection (Efficacy 41.83%; 95% CI 12.82 to 70.84) and HIV infection or death at 4 to 8 weeks (Efficacy 35.91%; 95% CI 8.41 to 63.41) but the effects were not sustained at 18 months.ZDV plus 3TC given to mothers during labour only (PETRA 'regimen C') with no treatment to babies did not reduce the risk of HIV infection at either 4 to 8 weeks or 18 months.In non-breastfeeding populations, three trials found that:ZDV given to mothers from 14 to 34 weeks gestation and during labour and to babies for the first 6 weeks after birth significantly reduced HIV infection in babies at 18 months (Efficacy 66.22%; 95% CI 33.94 to 98.50).ZDV given to mothers from 36 weeks gestation and during labour with no treatment to babies ('Thai-CDC regimen') significantly reduced HIV infection at 4 to 8 weeks (Efficacy 50.26%; 95% CI 13.80 to 86.72) but not at birthZDV given to mothers from 38 weeks gestation and during labour with no treatment to babies did not influence HIV transmission at 6 months.Longer versus shorter regimens using the same antiretrovirals One trial in a breastfeeding population found that:ZDV given to mothers during labour and to their babies for the first 3 days after birth compared with ZDV given to mothers from 36 weeks and during labour (similar to 'Thai-CDC') resulted in HIV infection rates that were not significantly different at birth, 4-8 weeks, 3 to 4 months, 6 months and 12 months.Three trials in non-breastfeeding populations found that:ZDV given to mothers from 28 weeks gestation during labour and to infants for the first 3 days after birth compared with ZDV given to mothers from 35 weeks gestation through labour and to infants from birth to 6 weeks significantly reduced HIV infection rate at 6 months (Efficacy 45.35 %; 95% CI 1.39 to 89.31) but compared with the same regimen ZDV given to mothers from 28 weeks gestation through labour and to infants from birth to 6 weeks did not result in a statistically significant difference in HIV infection at 6 months. ZDV given to mothers from 35 weeks gestation during labour and to infants for the first 3 days after birth was considered ineffective for reducing transmission rates and this regimen was discontinued.An antenatal/intrapartum course of ZDV used for a median of 76 days compared with an antenatal/intrapartum ZDV regimen used for a median 28 days with no treatment to babies in either group did not result in HIV infection rates that were significantly different at birth and at 3 to 4 months.In a programme where mothers were routinely receiving ZDV in the third trimester of pregnancy and babies were receiving one week of ZDV therapy, a single dose of nevirapine (NVP) given to mothers in labour and to their babies soon after birth compared with a single dose of NVP given to mothers only resulted in HIV infection rates that were not significantly different at birth and 6 months. However the reduction in risk of HIV infection or death at 6 months was marginally significant (Efficacy 45.00%; 95% CI -4.00 to 94.00).Antiretroviral regimens using different drugs and durations of treatmentIn breastfeeding populations, three trials found that:A single dose of NVP given to mothers at the onset of labour plus a single dose of NVP given to their babies immediately after birth ('HIVNET 012 regimen') compared with ZDV given to mothers during labour and to their babies for a week after birth resulted in lower HIV infection rates at 4-8 weeks (Efficacy 41.00%; 95% CI 11.84 to 70.16), 3-4 months (Efficacy 38.91%; 95% CI 11.24 to 66.58), 12 months (Efficacy 35.98 [9.25, 62.71]36.00%; 95% CI 8.56 to 63.44) and 18 months (Efficacy 39.15%; 95% CI 13.81 to 64.49). In addition, the NVP regimen significantly reduced the risk of HIV infection or death at 4-8 weeks (Efficacy 41.74%; 95% CI 14.30 to 69.18), 3 to 4 months (Efficacy 40.00%; 95% CI 14.34 to 65.66), 12 months (Efficacy 32.17%; 95% CI 8.51 to 55.83) and 18 months (Efficacy 32.57 [9.93, 55.21]33.00%; 95% CI 9.93 to 55.21).The 'HIVNET 012 regimen' plus ZDV given to babies for 1 week after birth compared with the 'HIVNET 012 regimen' alone did not result in a statistically significant difference in HIV infection at 4 to 8 weeks.A single dose of NVP given to babies immediately after birth plus ZDV given to babies for 1 week after birth compared with a single dose of NVP given to babies only significantly reduced the HIV infection rate at 4 to 8 weeks (Efficacy 36.79%; 95% CI 3.57 to 70.01).Five trials in non-breastfeeding populations found that:In a population in which mothers were receiving 'standard' antiretroviral for HIV infection a single dose of NVP given to mothers in labour plus a single dose of NVP given to babies immediately after birth ('HIVNET 012 regimen') compared with placebo did not result in a statistically significant difference in HIV infection rates at birth and at 4 to 8 weeks.The 'Thai CDC regimen' compared with the 'HIVNET 012 regimen' did not result in a significant difference in HIV infection at 4 to 8 weeks.A single dose of NVP given to babies immediately after birth compared to ZDV given to babies for the first 6 weeks after birth did not result in a significant difference in HIV infection rates at 4-8 weeks and 3 to 4 months. (ABSTRACT TRUNCATED)

Common occurrence of anaemia at the end of pregnancy following exposure to zidovudine-free regimens

OBJECTIVE

Although zidovudine-free regimens are increasingly used in pregnancy, their haematological effects in mothers and newborns are incompletely defined.

METHODS

The haematological profiles of 119 HIV-infected women and their neonates with highly active antiretroviral regimens (HAART) in pregnancy including or not zidovudine (ZDV) were investigated. Three groups were compared: 1) women who started ZDV-lamivudine (3TC)-based HAART during pregnancy (ZDVs, n = 60); 2) women on ZDV-3TC-based HAART from conception (ZDVc, n = 18); 3) women on ZDV-free HAART from conception (ZDVf, n = 41).

RESULTS

At the beginning of pregnancy, haemoglobin levels were similar in the three groups. By week 36 compared to baseline, haemoglobin levels had a significantly greater decrease in ZDVf women compared to ZDVs women (ZDVf: -2.03 g/dl; ZDVs: -1.36 g/dl, p = 0.036). A similar trend was observed for occurrence of maternal anaemia at 36 weeks. Newborns with no prenatal ZDV exposure had significantly higher haemoglobin levels at birth (ZDVf: 16.1 ± 1.4 g/dl, ZDVs: 14.3 ± 2.0 g/dl; ZDVc: 14.6 ± 2.4 g/dl, p = 0.044 and 0.003, respectively).

CONCLUSIONS

Half of ZDV-unexposed mothers had anaemia at the end of pregnancy, but their neonates had normal haemoglobin levels. ZDV initiation was associated with a lower occurrence of maternal anaemia during the third trimester and decreased haemoglobin levels in the newborns. We hypothesize that foetal iron requirements could represent a major determinant of maternal anaemia at the end of pregnancy.

Opt-out HIV testing: An ethical analysis of women’s reproductive rights

As the HIV epidemic continues to grow worldwide, women are increasingly and disproportionally affected. With the introduction of anti-retroviral medications that have been found to effectively prevent perinatal transmission of HIV, the approach to HIV testing in pregnant women has grown increasingly more controversial. In recent years, the model of voluntary counseling and testing (VCT) has come into question with opt-out testing now advocated for by the Centers for Disease Control and occurring widely in pregnancy. The benefits of opt-out testing are numerous and may justify its use in replacing the VCT that many have come to see as insufficient. An ethical analysis of opt-out testing suggests it may be at odds with true informed consent and involve a degree of coercion that would not be allowed outside the prenatal setting. If opt-out testing is going to remain the standard of care then the ethical issues it raises must be made transparent. Strategies need to be designed for ensuring that HIV counseling and testing in pregnancy is done in accordance with ethical and reproductive rights principles.

Safety and tolerability of antiretrovirals during pregnancy

Combination antiretroviral therapy (CART) dramatically decreases mother-to-child HIV-1 transmission (MTCT), but maternal adverse events are not infrequent. A review of 117 locally followed pregnancies revealed 7 grade ≥3 AEs possibly related to antiretrovirals, including 2 hematologic, 3 hepatic, and 2 obstetric cholestasis cases. A fetal demise was attributed to obstetric cholestasis, but no maternal deaths occurred. The drugs possibly associated with these AE were zidovudine, nelfinavir, lopinavir/ritonavir, and indinavir. AE or intolerability required discontinuation/substitution of nevirapine in 16% of the users, zidovudine in 10%, nelfinavir in 9%, lopinavir/ritonavir in 1%, but epivir and stavudine in none. In conclusion, nevirapine, zidovudine, and nelfinavir had the highest frequency of AE and/or the lowest tolerability during pregnancy. Although nevirapine and nelfinavir are infrequently used in pregnancy at present, zidovudine is included in most MTCT preventative regimens. Our data emphasize the need to revise the treatment recommendations for pregnant women to include safer and better-tolerated drugs.

Reduced thymic size but no evidence of impaired thymic function in uninfected children born to human immunodeficiency virus-infected mothers

BACKGROUND

HIV-exposed, uninfected (HIV-EU) infants present hematologic and immunologic abnormalities at birth, and it remains to be clarified whether these abnormalities persist beyond infancy, for instance, affecting vaccination responses.

METHODS

Thymic size and thymic output were evaluated in 20 HIV-EU children at 15 months of age and compared with 10 age- and gender-matched controls. Regulatory T-cells (Tregs) and immune activation as well as cytokine profiles were determined, and the antibody response to Haemophilus influenzae Type b (Hib) vaccination was evaluated.

RESULTS

Thymic size was significantly lower in HIV-EU children (P = 0.011). However, CD4 and CD8 counts did not differ between HIV-EU and control children. Likewise, thymic output estimated as CD4 cells expressing naive (CD45RA+CD62L+CD27+, P = 0.31) or recent thymic naive (CD45RA+CD27+CD31+, P = 0.13) phenotype, or CD4 cells containing T-cell receptor excision circles (P = 0.47) were comparable. HIV-EU children and controls had similar levels of activated cells (CD4+CD38+HLA-DR+, P = 0.87; CD8+CD38+HLA-DR+, P = 0.22), Tregs (CD4+CD25+CD127(low)FOXP3+, P = 0.53), and naive Tregs (CD4+CD25+CD127(low)FOXP3+CD45RA+CD27+, P = 0.65). Finally, comparable titers of Haemophilus influenzae Type b antibodies in the 2 groups were found (P = 0.43).

CONCLUSION

The study demonstrates reduced thymic size in HIV-EU children compared with children born to HIV-negative mothers, but no evidence of impaired thymic function, immune regulation, or antibody vaccination response was detected, suggesting that no qualitative immune deficits persist in HIV-EU children at 15 months of age.

Prevention of vertical transmission of HIV-1 in resource-limited settings

One of the most exciting areas of HIV research is that of prevention of vertical transmission from mother to child, since it accounts for 90% of childhood HIV infections, and therefore prevention in this context has an enormous potential impact on the spread of HIV among children. Focused research has yielded highly successful strategies for reducing infant infection rates, particularly in the developed world, and much work is underway to implement appropriate strategies in resource-limited settings, although this is not without challenges. Although transmission rates in some settings have been reduced to approximately 1%, scale-up and widespread implementation and application of strategic interventions for prevention of mother-to-child transmission of HIV during pregnancy, delivery and breastfeeding are needed in the developing world.

Dysregulation of CD4+CD25+CD127lowFOXP3+ regulatory T cells in HIV-infected pregnant women

Pregnancy represents a major challenge to immunologic tolerance. How the fetal “semiallograft” evades maternal immune attack is unknown. Pregnancy success may involve alteration of both central (thymic) and peripheral tolerance mechanisms. HIV infection is characterized by CD4+ T-cell depletion, chronic immune activation, and altered lymphocyte subsets. We studied immunologic consequences of pregnancy in 20 HIV-infected women receiving highly active antiretroviral therapy (HAART), and for comparison in 16 HIV-negative women. Lymphocyte subsets, thymic output, and cytokine profiles were measured prospectively during pregnancy and postpartum. A significant expansion of CD4+CD25+CD127lowFoxP3+ regulatory T cells indicating alteration of peripheral tolerance was seen during second trimester, but only in HIV-negative women. HIV-infected women had lower CD4 counts, lower thymic output and Th-2 cytokines, and more immune activation at all time points compared with controls. Immune activation was decreased in HIV-infected patients during pregnancy. In contrast, CD4 counts were increased in both groups. In conclusion, the study does not indicate that pregnancy adversely affects the immunologic course of HIV infection. However, despite HAART during pregnancy, HIV-infected women display different immunologic profiles from HIV-negative women, which may have importance for the induction of fetal-maternal tolerance and in part explain the increased risk of abortion in HIV-infected women.

Advances in prevention of mother-to-child HIV transmission: the international perspectives

We have sufficient knowledge and unprecedented access to global resources to dramatically reduce the transmission of HIV-1 from mother to children worldwide. Most transmission occurs during delivery and after birth through breastfeeding. For this reason, efforts to interrupt transmission have focused on peripartum period and safe infant feeding. This includes the use of antiretroviral therapy, elective cesarean section, avoidance of breastfeeding, and exclusive breastfeeding. This review summarizes recent studies and new international development on the prevention of mother-to-child HIV transmission. Prevention of mother-to-child transmission of HIV should now be integrated as part of basic maternal and child health services.

Postnatal infant HIV prophylaxis: a survey of U.S. practice

For neonates identified as at increased risk of acquiring HIV perinatally, the optimal postnatal prophylaxis regimen is not known. Current United States Public Health Service guidelines recognize that combination postnatal prophylaxis may be considered in some situations but that there are little data regarding the effectiveness and safety of any postnatal regimen besides zidovudine. The actual use of combination postnatal regimens in the United States has not previously been described. We conducted a national, Web-based survey between December 2009 and January 2010 to describe the percent of providers who prescribe combination postnatal prophylaxis, the antiretroviral combinations they used, and the risk factors that might elicit combination postnatal prophylaxis. 472 known or possible perinatal HIV providers were queried; 42% (n = 197) responded and 68% of respondents (134) were eligible to complete the survey. Sixty-two percent (n = 83) of participating providers reported use or recommendation of combination postnatal prophylaxis in the last year. Three drugs, zidovudine, lamivudine and nevirapine, comprised 77% of first-choice combination regimens. Lopinivir-ritonivir (LPV/RTV) was included in 16% of all reported regimens. Combination postnatal prophylaxis was strongly preferred in patient-based scenarios with additional risk factors for perinatal HIV transmission.

Antiretroviral pharmacology: special issues regarding pregnant women and neonates

Antiretrovirals may be used in pregnant women infected with the HIV and their newborns both for treatment of maternal HIV disease and for prevention of mother-to-child transmission of HIV. More than 25 antiretroviral agents in 5 classes have been approved, with new drugs and classes in development. This article reviews current knowledge of the pharmacology of these drugs during pregnancy and in the newborn period, highlighting those pharmacologic issues critical to the safe and effective use of antiretrovirals in these populations.

HIV drug resistance and mother-to-child transmission of HIV

This article covers HIV drug resistance among pregnant women and the implications of transmission of resistant HIV to the infant. Resistance to antiretroviral drugs may be acquired or can emerge while HIV-infected pregnant women are on antiretroviral therapy, either before or during pregnancy. Resistance to antiretroviral drugs among HIV-infected infants may be acquired from the mother in utero or during the intrapartum period. Resistance may also emerge from exposure to antiretroviral drugs given to the infant for prophylaxis against HIV transmission. In settings where breastfeeding is practiced, ongoing transmission of HIV from breastfeeding may lead to transmission of resistant HIV from the mother. If the mother is taking antiretroviral drugs while breastfeeding, resistance to antiretroviral drugs may emerge in an HIV-infected infant from ingestion of antiretroviral drugs via breast milk. The magnitude and implications of antiretroviral resistance among HIV-infected pregnant women and HIV-infected infants are summarized.

Vertical transmission of HIV-an update

One of the greatest successes in AIDS research to date has by far been the discovery of successful interventions that interrupt the transmission of HIV from mother to child. It is however important to note that these successes have occurred largely in countries with great resources and the least burden of perinatal transmission of HIV. In the developing world wherein currently 95% of vertical transmission of HIV occurs, it is highly condemnable that still every minute an infected infant is said to be born in spite of the fact that vertical transmission is largely preventable, mainly because translating knowledge into practice is not always possible or feasible; This has led to a continuous growing numbers of children with HIV, thereby making pediatric HIV a looming problem rapidly draining the already burdened health care system of these countries. It is the need of the hour to appropriately address the challenges to achieve zero percent transmission of HIV from an infected mother to her child thereby giving a hope for an AIDS-free new generation worldwide.

Evidence of impact of maternal HIV infection on immunoglobulin levels in HIV-exposed uninfected children

HIV infection affects B cell function and is associated with increased immunoglobulin levels, including in HIV-infected pregnant women. It is unknown if maternal HIV infection affects immunoglobulins in their uninfected children. We investigated this using prospective longitudinal data from children born to HIV-infected women enrolled in the European Collaborative Study (ECS). Data from children enrolled in the European Paediatric Hepatitis C Virus Network (EPHN) were used as a comparison group. Associations between infant and maternal factors and child log(10) total IgG, IgM, and IgA levels were quantified in linear regression analyses. A total of 1751 HIV-uninfected (ECS) and 167 HCV-uninfected children (EPHN) were included. HIV-uninfected children had significantly higher IgG, IgM, and IgA levels than HCV-uninfected children up to at least 24 months. Among HIV-exposed uninfected children, IgG levels from birth until 5 years of age were correlated with increased maternal IgG levels. ART exposure in fetal and early neonatal life was associated with lower IgG. These findings indicate alterations in immunoglobulin levels in uninfected children born to HIV-infected women, suggesting that fetal exposure to a chronically activated maternal immune system is associated with an altered humoral response.

Antiretroviral prophylaxis to prevent perinatal HIV transmission in St. Petersburg, Russia: too little, too late

BACKGROUND

We evaluated the influence of type and timing of prophylaxis on perinatal HIV transmission in St. Petersburg, Russia.

METHODS

We linked surveillance data for 1498 HIV-infected mothers delivering from 2004 to 2007 with polymerase chain reaction data for 1159 infants to determine predictors of transmission.

RESULTS

The overall perinatal transmission rate was 6.3% [73 of 1159, 95% confidence interval (CI) 4.9% to 7.7%]. Among the 12.8% (n = 149) of mother-infant pairs receiving full course (antenatal, intrapartum, postnatal) dual/triple antiretroviral prophylaxis, the transmission rate was 2.7%. Among the 1010 receiving less complete regimens (full course zidovudine, single-dose nevirapine, or incomplete), transmission ranged from 4.1% to 12.2%. Among the 28.9% (330) of mothers initiating antiretroviral drugs <or=20 weeks gestation, perinatal transmission was 1.8%, compared with 4.0%, 8.6%, and 11.3% for those initiating antiretrovirals at 21-28 weeks, 29-42 weeks, or during labor and delivery, respectively (P for trend <0.0001). Compared with those initiating antepartum prophylaxis <or=20 weeks, those initiating antepartum prophylaxis >or=29 weeks (or not at all) had increased transmission odds (adjusted odds ratio: 4.9, 95% CI: 1.8 to 12.9; odds ratio: 5.1, 95% CI: 2.0 to 13.1, respectively).

CONCLUSIONS

In St. Petersburg, the potential for further reductions in perinatal transmission is evident, given low transmission among women receiving early combination prophylaxis.

HIV infection in women: do sex and gender matter?

At least half of all HIV infections occur in women. Most women are of childbearing potential; therefore, issues encompassing reproduction and mother-to-child transmission are critical in the management of this population. The efficacy of antiretroviral therapy (ART) is similar in men and women, although rates of adverse events or toxicity may be higher in women, which, in turn, may be related to higher antiretroviral drug levels documented in pharmacokinetic studies. A substantial proportion of women may not derive the benefit of highly active ART because nonsuppressive regimens are commonly used, especially in resource-limited settings, to decrease mother-to-child transmission. The likely emergence of resistant virus can have long-term sequelae for the mother, child, and other exposed individuals. Additional studies are needed of sex/gender-related issues including antiretroviral toxicities, pharmacokinetic profiles of approved and novel agents, ART strategies during pregnancy to minimize HIV resistance, and determination of optimal antiretroviral regimens for women.

Italian consensus statement on paediatric HIV infection

The objective of this document is to identify and reinforce current recommendations concerning the management of HIV infection in infants and children in the context of good resource availability. All recommendations were graded according to the strength and quality of the evidence and were voted on by the 57 participants attending the first Italian Consensus on Paediatric HIV, held in Siracusa in 2008. Paediatricians and HIV/AIDS care specialists were requested to agree on different statements summarizing key issues in the management of paediatric HIV. The comprehensive approach on preventing mother-to-child transmission (PMTCT) has clearly reduced the number of children acquiring the infection in Italy. Although further reduction of MTCT should be attempted, efforts to personalize intervention to specific cases are now required in order to optimise the treatment and care of HIV-infected children. The prompt initiation of treatment and careful selection of first-line regimen, taking into consideration potency and tolerance, remain central. In addition, opportunistic infection prevention, adherence to treatment, and long-term psychosocial consequences are becoming increasingly relevant in the era of effective antiretroviral combination therapies (ART). The increasing proportion of infected children achieving adulthood highlights the need for multidisciplinary strategies to facilitate transition to adult care and maintain strategies specific to perinatally acquired HIV infection.

[AIDS Study Group/Spanish AIDS Plan consensus document on antiretroviral therapy in adults with human immunodeficiency virus infection (updated January 2010)]

OBJECTIVE

This consensus document is an update of antiretroviral therapy recommendations for adult patients with human immunodeficiency virus infection.

METHODS

To formulate these recommendations a panel made up of members of the Grupo de Estudio de Sida (Gesida, AIDS Study Group) and the Plan Nacional sobre el Sida (PNS, Spanish AIDS Plan) reviewed the advances in the current understanding of the pathophysiology of human immunodeficiency virus (HIV) infection, the efficacy and safety of clinical trials, and cohort and pharmacokinetic studies published in biomedical journals or presented at scientific meetings. Three levels of evidence were defined according to the data source: randomized studies (level A), cohort or case-control studies (level B), and expert opinion (level C). The decision to recommend, consider or not to recommend ART was established in each situation.

RESULTS

Currently, the treatment of choice for chronic HIV infection is the combination of three drugs of two different classes, including 2 nucleosides or nucleotide analogs (NRTI) plus 1 non-nucleoside (NNRTI) or 1 boosted protease inhibitor (PI/r), but other combinations are possible. Initiation of ART is recommended in patients with symptomatic HIV infection. In asymptomatic patients, initiation of ART is recommended on the basis of CD4 lymphocyte counts, plasma viral load and patient co-morbidities, as follows: 1) therapy should be started in patients with CD4 counts below 350 cells/microl; 2) When CD4 counts are between 350 and 500 cells/microl, therapy should be started in case of cirrhosis, chronic hepatitis C, high cardiovascular risk, HIV nephropathy, HIV viral load above 100,000 copies/ml, proportion of CD4 cells under 14%, and in people aged over 55; 3) Therapy should be deferred when CD4 are above 500 cells/microl, but could be considered if any of previous considerations concurs. Treatment should be initiated in case of hepatitis B requiring treatment and should be considered for reduce sexual transmission. The objective of ART is to achieve an undetectable viral load. Adherence to therapy plays an essential role in maintaining antiviral response. Therapeutic options are limited after ART failures but undetectable viral loads maybe possible with the new drugs even in highly drug experienced patients. Genotype studies are useful in these situations. Drug toxicity of ART therapy is losing importance as benefits exceed adverse effects. Criteria for antiretroviral treatment in acute infection, pregnancy and post-exposure prophylaxis are mentioned as well as the management of HIV co-infection with hepatitis B or C.

CONCLUSIONS

CD4 cells counts, viral load and patient co-morbidities are the most important reference factors to consider when initiating ART in asymptomatic patients. The large number of available drugs, the increased sensitivity of tests to monitor viral load, and the ability to determine viral resistance is leading to a more individualized therapy approach in order to achieve undetectable viral load under any circumstances.

Celiac disease and its effect on human reproduction: a review

All decisions about initiating, continuing, or stopping therapy of the hepatitis B virus (HBV) during pregnancy must include an analysis of the risks and benefits for mother and fetus. The trimester of the pregnancy and the stage of the mother’s liver disease are important factors. Treatment in the third trimester may be initiated to aid in preventing perinatal transmission, which appears to be most pronounced in mothers with high viral loads. Consideration of initiating treatment in the third trimester should occur after a high viral load is documented in the latter part of the second trimester, to allow adequate time for initiation of antiviral therapy with significant viral suppression before delivery. This discussion should include the topic of breastfeeding, because it is generally not recommended while receiving antiviral therapy. Currently, lamivudine and tenofovir appear to be the therapeutic options with the most reasonable safety data in pregnancy.

Antiretroviral-related hematologic short-term toxicity in healthy infants: implications of the new neonatal 4-week zidovudine regimen

Recent updates of the guidelines on the prevention of human immunodeficiency virus mother-to-child transmission have shortened the neonatal zidovudine prophylactic regimens from 6 to 4 weeks. We present a prospective observational study in a large cohort of mother-infant pairs and report that the 4-week regimen allows an earlier recovery of the anemia in these otherwise healthy infants.

A review of nucleoside reverse transcriptase inhibitor use to prevent perinatal transmission of HIV

Worldwide, women comprise > 50% of all people living with HIV and the vast majority of these women are of childbearing age. In fact, a significant proportion of these women are identified as HIV-infected during pregnancy. Preventing perinatal transmission has been one of the greatest prevention successes of the HIV epidemic with < 2% of live births resulting in an HIV-infected infant. The strategic use of combination antiretroviral therapy has been a critical component of this reduction. With more antiretroviral agents available for HIV, the appropriate selection of therapy is often based on provider familiarity with the various agents. Although benefits of antiretroviral use in pregnancy tremendously outweigh the risks, concerns regarding short- and long-term toxicity in mothers and their children, in addition to the risk of the development of HIV resistance, remain subjects of discussion. The choice of antiretroviral 'backbone' is supported by extensive data showing efficacy in the prevention of HIV vertical transmission. Co-formulated zidovudine/lamivudine is the most commonly used combination in pregnancy. Long-term consequences of in utero exposure to antiretroviral agents are not fully understood. In this article, we review the data regarding nucleoside reverse transcriptase inhibitors with a focus on tenofovir.

Acceptance of HIV-infected patients in assisted reproductive technique protocols

OBJECTIVE

To assess the adequacy of a multidisciplinary approach providing information to couples affected by HIV before ART.

DESIGN

Prospective observational study.

SETTING

RT centre and infectious disease clinic, public university hospital.

PATIENTS

50 couples with at least one HIV-infected partner.

INTERVENTIONS

Multidisciplinary approach towards ART by various intervening physicians (specialist in fertility, infectious diseases, paediatrics, obstetrics, psychiatry).

MAIN OUTCOME MEASURED

We analysed specifically the cases in which the staff did not accept and the patient's compliance to the counselling procedures.

RESULTS

Among the 150 couples, 30 did not complete the procedure and were lost to follow-up. The remaining 120 couples were evaluated: 89 couples were accepted, 5 were temporarily refused and 26 were refused definitively. The major reasons for refusal were medical reasons (n=13).

CONCLUSION

Because of the high refusal rate and the drop of rate, a multidisciplinary approach is mandatory before initiating ART in seropositive couples.

The importance of identifying and treating depression in HIV infected, pregnant women: a review

Women make up approximately half of all HIV infections worldwide. A substantial number of women living with HIV in the United States are of childbearing age and many of these women will become pregnant each year. These women must navigate the complexities of two health concerns (HIV infection and pregnancy) and the complexities of two health care provision systems (obstetrics and infectious disease). The goal of HIV treatment during pregnancy is to optimize health of the mother and minimize risk of vertical transmission. To realize these goals, high levels of adherence to antiretroviral therapy (ART) and periodic contact with medical professionals are required. Depression is not uncommon in pregnant women and has been identified as a robust predictor of non-adherence to ART and implicated in difficulty utilizing prenatal care. The purpose of the current article is to review evidence in support of diagnosis and treatment, when appropriate, of unipolar depression in HIV positive, pregnant women in developed nations. The article begins by defining the scope of the problem. Assessment and treatment options are discussed, followed by suggestions for future research.

German-Austrian recommendations for HIV1-therapy in pregnancy and in HIV1-exposed newborn, update 2008

In Germany during the last years about 200-250 HIV1-infected pregnant women delivered a baby each year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care. In those cases, where HIV1-infection was known during pregnancy, since 1995 the rate of vertical transmission of HIV1 was reduced to 1-2%. - This low transmission rate has been achieved by the combination of anti-retroviral therapy of pregnant women, caesarean section scheduled before onset of labour, anti-retroviral post exposition prophylaxis in the newborn and refraining from breast-feeding by the HIV1-infected mother. To keep pace with new results in research, approval of new anti-retroviral drugs and changes in the general treatment recommendations for HIV1-infected adults, in 1998, 2001, 2003 and 2005 an interdisciplinary consensus meeting was held. Gynaecologists, infectious disease specialists, paediatricians, pharmacologists, virologists and members of the German AIDS Hilfe (NGO) were participating in this conference to update the prevention strategies. A fifth update became necessary in 2008. The updating process was started in January 2008 and was terminated in September 2008. The guidelines provide new recommendations on the indication and the starting point for HIV-therapy in pregnancies without complications, drugs and drug combinations to be used preferably in these pregnancies and updated information on adverse effects of anti-retroviral drugs. Also the procedures for different scenarios and risk constellations in pregnancy have been specified again. - With these current guidelines in Germany and Austria the low rate of vertical HIV1-transmission should be further maintained.

Cost-effectiveness of routine rapid human immunodeficiency virus antibody testing before DNA-PCR testing for early diagnosis of infants in resource-limited settings

BACKGROUND

Infants born to HIV-infected women should receive HIV testing to allow early diagnosis and treatment. Recommendations for resource-limited settings stress laboratory-based virologic assays. While effective, these tests are logistically complex and expensive. This study explored the cost-effectiveness of incorporating initial screening with rapid HIV tests (RHT) into the conventional testing algorithm to screen-out HIV-uninfected infants, thereby reducing the need for costly virologic testing.

METHODS

Data on HIV prevalence, RHT sensitivity and specificity, and costs were collected from 820 HIV-exposed children (1.5-18 months) attending 2 postnatal screening programs in Uganda during July 2005 to December 2006. Cost-effectiveness models compared the conventional testing algorithm DNA polymerase chain reaction (DNA-PCR with Roche Amplicor v1.5) with a modified algorithm (initial RHT to screen-out HIV-uninfected infants before DNA-PCR).

RESULTS

The model estimated that the conventional algorithm would identify 94.3% (91.8%-94.7%) of HIV-infected infants, compared with 87.8% (79.4%-90.5%) for a modified algorithm using RHT (HIV 1/2 Determine) and excluding the need for DNA-PCR for HIV antibody-negative infants. Costs per infant were $23.47 ($23.32-$23.76) for the conventional algorithm and between $22.75 ($21.89-$23.31) and $7.58 ($6.41-$10.75) for the modified algorithm, depending on infant age and symptoms. Compared with the conventional algorithm, costs per HIV-infected infant identified using the modified algorithm were higher in 1.5-to 3-month-old infants, but significantly lower in 3-month-old and older infants. Models replicating the whole infant testing program showed the modified algorithm would have marginally lower sensitivity, but would reduce total program costs by 27% to 40%, producing an incremental cost-effectiveness ratio of $1489 ($686-$6781) for the conventional versus modified algorithms.

CONCLUSIONS

Screening infants with RHT before DNA-PCR is cost-effective in infants 3 months old or older. Incorporating RHT into early infant testing programs could improve cost-effectiveness and reduce program costs.

No relation between in-utero exposure to HAART and intrauterine growth retardation

BACKGROUND

The use of HAART during pregnancy is now standard care to prevent mother-to-child HIV transmission in developed countries. There is controversy about its impact on low birth weight.

OBJECTIVE

To evaluate the impact of antiretroviral therapy during the pregnancy on birth weight, length and head circumference.

METHODS

The study was performed in uninfected infants born to HIV-1-infected mothers, enrolled from 1990 to 2006 in the Agence Nationale de Recherche sur le SIDA French Perinatal Cohort CO1. We excluded mothers who used illicit drugs during pregnancy or had no prenatal care before the third trimester, twins and stillbirths. We used Z-scores adjusted for gestational age and sex.

RESULTS

In 8192 mother-infant pairs, the mean birth weight Z-scores increased between 1990 and 1997 and then remained stable until 2006. There was no significant relation between the type of antiretroviral therapy and the proportion of small for gestational age (birth weight Z-score < or = -2SD), which was 4% overall. Infants exposed to HAART compared with monotherapy had a lower mean birth weight Z-scores (difference -0.09, 95% confidence interval -0.15 to -0.02); however, there was no difference between HAART exposure in 2005-2006 and monotherapy in 1999-2004, which corresponded to standard care during each period, respectively. Length or head circumference Z-scores were not associated with antiretroviral therapy exposure. Among pregnancies with HAART, there was no relation between the duration and type of therapy and the anthropometric parameters.

CONCLUSION

Our findings in a large cohort suggest that HAART during pregnancy does not increase the incidence of infants who are small for gestational age.

Tolerance and viral resistance after single-dose nevirapine with tenofovir and emtricitabine to prevent vertical transmission of HIV-1

OBJECTIVE

Viral resistance occurs with high frequency after single-dose nevirapine. We aimed to evaluate the safety and resistance profiles of a combination of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) in HIV-1-infected pregnant women and their newborns.

DESIGN

An open-label phase I/II trial in Côte d'Ivoire, Cambodia and South Africa.

METHODS

Women received antenatal zidovudine, intrapartum single-dose nevirapine and two tablets of TDF/FTC and one daily tablet of TDF/FTC during the 7 days postpartum. Their infants received single-dose nevirapine and zidovudine for 1 week. Serious adverse events (SAEs), kinetic of maternal plasma HIV-1 RNA viral load, genotypic resistance at 28 days postpartum and paediatric HIV-1 infection at 3, 28 and 45 days of life were assessed.

RESULTS

Thirty-eight HIV-1-infected pregnant women were enrolled (19 in Abidjan, 12 in Phnom Penh and seven in Soweto) with a median CD4 cell count of 450 cells/microl and median viral load of 4.08 log10 copies/ml. Women received TDF/FTC 4.9 h in median before delivery. Biological SAEs occurred in nine women. Among 39 live births, nine infants had clinical SAEs, including four deaths, and two developed severe anaemia. These SAEs were not likely to be related to TDF/FTC. Maternal viral load decreased by a median of 0.90 log10 copies/ml at 2 days postpartum and returned to baseline value at 28 days. No intrapartum HIV transmission was reported. No genotypic resistance mutation to zidovudine, nevirapine, FTC or TDF was detected.

CONCLUSION

The TDF/FTC combination was well tolerated in delivering women and exposed newborns. Nevirapine viral resistance appears to have been avoided by the intrapartum and 7-day postpartum TDF/FTC regimen.

Amniocentesis and mother-to-child human immunodeficiency virus transmission in the Agence Nationale de Recherches sur le SIDA et les Hépatites Virales French Perinatal Cohort

OBJECTIVE

The objective of the study was to investigate whether performing an amniocentesis increased mother-to-child transmission of human immunodeficiency virus (HIV)-1 (MTCT).

STUDY DESIGN

We studied HIV -1 infected mothers and their children enrolled in the multicenter French Perinatal HIV Cohort from 1985 to 2006.

RESULTS

One hundred sixty-six amniocenteses were performed among 9302 singleton pregnancies, the proportion increasing from 1.0% before 2001 to 4.7% in 2005-2006. Use of highly active antiretroviral therapy (HAART) was more frequent in the amniocentesis group (58.4% vs 33.2%). MTCT tended to be higher in the amniocentesis group, among mothers who received no antiretroviral agents (25.0%; 3/12 vs 16.2%; 343/2113; P = .41) as well as among mothers receiving zidovudine monotherapy or a double-nucleoside reverse transcriptase inhibitor combination (6.1%; 3/49 vs 3.3%; 117/3556; P = .22), but the difference was not significant. Among 81 mothers receiving HAART, there was no case of MTCT.

CONCLUSION

Our results suggest that amniocentesis is not a major risk factor for mother-to-child transmission in mothers treated with effective antiretroviral therapy.