Maternal 12-month response to antiretroviral therapy following prevention of mother-to-child transmission of HIV type 1, Ivory Coast, 2003-2006

Medication adherence in pregnant women with human immunodeficiency virus receiving antiretroviral therapy in sub-Saharan Africa: a systematic review

BACKGROUND

The use of antiretroviral therapy (ART) is a core strategy proposed by the World Health Organization in preventing mother to child transmission (MTCT) of HIV. This systematic review aimed to examine the enablers and barriers of medication adherence among HIV positive pregnant women in sub-Saharan Africa.

METHODS

We used the following keywords: HIV AND (Pregnancy OR Pregnant*) AND (PMTCT OR "PMTCT Cascade" OR "Vertical Transmission" OR "Mother-to-Child") AND (Prevent OR Prevention) AND (HAART OR "Antiretroviral Therapy" OR "Triple Therapy") AND (Retention OR Concordance OR Adherence OR Compliance) to conduct electronic searches in the following databases: MEDLINE Complete (1916-Dec 2017), Embase (1947-Dec 2017), Global Health (1910-Dec 2017) and CINAHL Complete (1937-Dec 2017). Of the four databases searched, 401 studies were identified with 44 meeting the inclusion criteria. Seven studies were added after searching reference lists of included articles, resulting in 51 articles in total.

RESULTS

The review demonstrated that stigma, cost of transportation, food deprivation and a woman's disclosure or non-disclosure of her HIV status to a partner, family and the community, could limit or define the extent of her adherence to prescribed antiretroviral drugs during pregnancy. Furthermore, the review indicated that knowledge of HIV status, either before or during pregnancy, was significantly associated with medication adherence. Women who knew their HIV status before pregnancy demonstrated good adherence while women who found out their HIV infection status during pregnancy were linked with non-adherence to ART.

CONCLUSION

This review revealed several barriers and enablers of adherence among pregnant women taking ART in sub-Saharan Africa. Major barriers included the fear of HIV infection status disclosure to partners and family members, stigma and discrimination. A major enabler of adherence in women taking ART was women's knowledge of their HIV status prior to becoming pregnant. Enhanced effort is needed to facilitate women's knowledge of their HIV status before pregnancy to enable disease acceptance and management, and to support pregnant women and her partner and family in dealing with fear, stigma and discrimination about HIV.

Timing of pregnancy, postpartum risk of virologic failure and loss to follow-up among HIV-positive women

OBJECTIVES

We assessed the association between the timing of pregnancy with the risk of postpartum virologic failure and loss from HIV care in South Africa.

DESIGN

This is a retrospective cohort study of 6306 HIV-positive women aged 15-49 at antiretroviral therapy (ART) initiation, initiated on ART between January 2004 and December 2013 in Johannesburg, South Africa.

METHODS

The incidence of virologic failure (two consecutive viral load measurements of >1000 copies/ml) and loss to follow-up (>3 months late for a visit) during 24 months postpartum were assessed using Cox proportional hazards modelling.

RESULTS

The rate of postpartum virologic failure was higher following an incident pregnancy on ART [adjusted hazard ratio 1.8, 95% confidence interval (CI): 1.1-2.7] than among women who initiated ART during pregnancy. This difference was sustained among women with CD4 cell count less than 350 cells/μl at delivery (adjusted hazard ratio 1.8, 95% CI: 1.1-3.0). Predictors of postpartum virologic failure were being viremic, longer time on ART, being 25 or less years old and low CD4 cell count and anaemia at delivery, as well as initiating ART on stavudine-containing or abacavir-containing regimen. There was no difference postpartum loss to follow-up rates between the incident pregnancies group (hazard ratio 0.9, 95% CI: 0.7-1.1) and those who initiated ART in pregnancy.

CONCLUSION

The risk of virologic failure remains high among postpartum women, particularly those who conceive on ART. The results highlight the need to provide adequate support for HIV-positive women with fertility intention after ART initiation and to strengthen monitoring and retention efforts for postpartum women to sustain the benefits of ART.

A post-partum single-dose TDF/FTC tail does not prevent the selection of NNRTI resistance in women receiving pre-partum ZDV and intrapartum single-dose nevirapine to prevent mother-to- child HIV-1 transmission

Although the rates of vertical transmission of HIV in the developing world have improved to around 3% in countries like South Africa, resistance to antiretrovirals (ARV) used in Prevention of Mother‐to‐Child transmission (pMTCT) strategies may thwart such outcomes and affect the efficacy of future ARV regimens in mothers and children. This study conducted in Durban, South Africa, between 2010 and 2013 found a high rate of nevirapine (NVP) resistance among women receiving Zidovudine (AZT) from 14 weeks gestation, single dose nevirapine (sd NVP) at the onset of labor and a single dose of coformulated Tenofovir/Emtricitabine (TDF/FTC) postpartum. Using Sanger sequencing, high and intermediate levels of nevirapine (NVP) resistance were detected in 15/44 (34%) and in 1/44 (2%) of women tested, respectively. Most subjects selected the K103N mutation (22% (10/45) of all patients and 66% (10/15) of those with high‐level NVP resistance). Such rate of NVP resistance is comparable to studies where only sd NVP was used. In conclusion, a post‐partum single‐dose TDF/FTC tail does not prevent the selection of NNRTI resistance in women receiving pre‐partum ZDV and intrapartum sd NVP to prevent mother‐to‐child HIV‐1 transmission. J. Med. Virol. 87:1662–1667, 2015. © 2015 The Authors. Journal of Medical Virology published by Wiley Periodicals, Inc.

Pregnancy is associated with elevation of liver enzymes in HIV-positive women on antiretroviral therapy

Objective:

The objective of this study is to assess whether pregnancy is associated with an increased risk of liver enzyme elevation (LEE) and severe LEE in HIV-positive women on antiretroviral therapy (ART).

Design:

Two observational studies: the UK Collaborative HIV Cohort (UK CHIC) study and the UK and Ireland National Study of HIV in Pregnancy and Childhood (NSHPC).

Methods:

Combined data from UK CHIC and NSHPC were used to identify factors associated with LEE (grade 1–4) and severe LEE (grade 3–4). Women starting ART in 2000–2012 were included irrespective of pregnancy status. Cox proportional hazards were used to assess fixed and time-dependent covariates including pregnancy status, CD4⁺ cell count, drug regimen and hepatitis B virus/hepatitis C virus (HBV/HCV) coinfection.

Results:

One-quarter (25.7%, 982/3815) of women were pregnant during follow-up, 14.2% (n = 541) when starting ART. The rate of LEE was 14.5/100 person-years in and 6.0/100 person-years outside of pregnancy. The rate of severe LEE was 3.9/100 person-years in and 0.6/100 person-years outside of pregnancy. The risk of LEE and severe LEE was increased during pregnancy [LEE: adjusted hazard ratio (aHR) 1.66 (1.31–2.09); severe LEE: aHR 3.57 (2.30–5.54)], including in secondary analyses excluding 541 women pregnant when starting ART. Other factors associated with LEE and severe LEE included lower CD4⁺ cell count (<250 cells/μl), HBV/HCV coinfection and calendar year.

Conclusion:

Although few women developed severe LEE, this study provides further evidence that pregnancy is associated with an increased risk of LEE and severe LEE, reinforcing the need for regular monitoring of liver biomarkers during pregnancy.

Virologic and immunologic failure, drug resistance and mortality during the first 24 months postpartum among HIV-infected women initiated on antiretroviral therapy for life in the Mitra plus Study, Dar es Salaam, Tanzania

Background

In the Mitra plus study of prevention of mother-to-child transmission of HIV-1, which included 501 women in Dar es Salaam, Tanzania, triple antiretroviral therapy (ART) was given from late pregnancy throughout breastfeeding up to 6 months postnatally. Here we report findings in a sub-cohort of women with ≤200 CD4cells/μL at enrolment who were continued on ART for life and followed up during 24 months after delivery to determine virologic and immunologic responses, drug resistance and mortality.

Methods

Blood samples for viral load and CD4 counts testing were collected at enrolment and at 3, 6, 12 and 24 months postpartum. HIV drug resistance testing was performed at 12 months. Data analysis included descriptive statistics and multivariate analysis using Generalized Estimated Equations of 73 women with at least two postpartum assessments. The mortality analysis included 84 women who had delivered.

Results

The proportion of women with a viral load ≥400 copies/mL was 97% (71/73) at enrolment, 16% (11/67), 22% (15/69), 61% (36/59) and 86% (48/56) at 3, 6, 12 and 24 months postpartum, respectively. The proportion of women with immunologic failure was 12% (8/69), 25% (15/60) and 41% (24/58) at 6, 12 and 24 months, respectively. At 12 months, drug resistance was demonstrated in 34% (20/59), including 12 with dual-class resistance. Self-report on drug adherence was 95% (64/68), 85% (56/66), 74% (39/53) and 65% (30/46) at 3, 6, 12 and 24 months, respectively. The mortality rate was 5.9% (95% CI 2.5-13.7%) at 24 months. The probability of virologic and immunologic failure was significantly higher among women who reported non-perfect adherence to ART at month 24 postpartum.

Conclusions

Following an initial decline of viral load, virologic failure was common at 12 and 24 months postpartum among women initiated on ART for life during pregnancy because of low CD4 cell counts. A high proportion of viremic mothers also had resistance mutations. However, at 24 months follow-up, the mortality rate was still fairly low. Continuous adherence counseling and affordable means of monitoring of the virologic response are crucial for successful implementation of the WHO Option B+ guidelines to start all HIV-infected pregnant women on ART for life.

Quantification of total HIV1-DNA in peripheral blood mononuclear cells

HIV reservoir measurement in patients is one of the challenges at the time of testing new treatment approaches aiming at eradicating HIV infection. HIV reservoirs are complex and disseminated in a large number of organs and lymphoid tissues. We chose to quantify total cell-associated HIV-DNA in PBMC as a marker of HIV reservoirs and described the method we developed. The marker was used in large cohort studies at different stages of HIV disease and in therapeutical trials. Our results show how informative is this marker, as well as that plasma HIV-RNA and CD4 T cell count are representative of each patient when measured in blood. Such a series of results might help to adapt simplification or structured interruption strategies, design new clinical trials targeting HIV reservoirs, and select populations that could benefit of such new treatments.

Representation of women and pregnant women in HIV research: a limited systematic review

BACKGROUND

HIV-related outcomes may be affected by biological sex and by pregnancy. Including women in general and pregnant women in particular in HIV-related research is important for generalizability of findings.

OBJECTIVE

To characterize representation of pregnant and non-pregnant women in HIV-related research conducted in general populations.

DATA SOURCES

All HIV-related articles published in fifteen journals from January to March of 2011. We selected the top five journals by 2010 impact factor, in internal medicine, infectious diseases, and HIV/AIDS.

STUDY ELIGIBILITY CRITERIA

HIV-related studies reporting original research on questions applicable to both men and women of reproductive age were considered; studies were excluded if they did not include individual-level patient data.

STUDY APPRAISAL AND SYNTHESIS METHODS

Articles were doubly reviewed and abstracted; discrepancies were resolved through consensus. We recorded proportion of female study participants, whether pregnant women were included or excluded, and other key factors.

RESULTS

In total, 2014 articles were published during this period. After screening, 259 articles were included as original HIV-related research reporting individual-level data; of these, 226 were determined to be articles relevant to both men and women of reproductive age. In these articles, women were adequately represented within geographic region. The vast majority of published articles, 183/226 (81%), did not mention pregnancy (or related issues); still fewer included pregnant women (n=33), reported numbers of pregnant women (n=19), or analyzed using pregnancy status (n=9).

LIMITATIONS

Data were missing for some key variables, including pregnancy. The time period over which published works were evaluated was relatively short.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

The under-reporting and inattention to pregnancy in the HIV literature may reduce policy-makers' ability to set evidence-based policy around HIV/AIDS care for pregnant women and women of child-bearing age.

Incident pregnancy and time to death or AIDS among HIV-positive women receiving antiretroviral therapy

Background

Little is known about the impact of pregnancy on response to highly active antiretroviral therapy (HAART) in sub-Saharan Africa. We examined the effect of incident pregnancy after HAART initiation on clinical response to HAART.

Methods

We evaluated a prospective clinical cohort of adult women initiating HAART in Johannesburg, South Africa between 1 April 2004 and 31 March 2011, and followed up until an event, transfer, drop-out, or administrative end of follow-up on 30 September 2011. Women over age 45 and women who were pregnant at HAART initiation were excluded from the study. Main exposure was having experienced pregnancy after HAART initiation; main outcome was death and (separately) death or new AIDS event. We calculated adjusted hazard ratios (HRs) and 95% confidence limits (CL) using marginal structural Cox proportional hazards models.

Results

The study included 7,534 women, and 20,813 person-years of follow-up; 918 women had at least one recognized pregnancy during follow-up. For death alone, the weighted (adjusted) HR was 0.84 (95% CL 0.44, 1.60). Sensitivity analyses confirmed main results, and results were similar for analysis of death or new AIDS event. Incident pregnancy was associated with a substantially reduced hazard of drop-out (HR = 0.62, 95% CL 0.51, 0.75).

Conclusions

Recognized incident pregnancy after HAART initiation was not associated with increases in hazard of clinical events, but was associated with a decreased hazard of drop-out. High rates of pregnancy after initiation of HAART may point to a need to better integrate family planning services into clinical care for HIV-infected women.

Lesotho's minimum PMTCT package: lessons learned for combating vertical HIV transmission using co-packaged medicines

Introduction

Mother-to-child transmission of HIV can be reduced to<5% with appropriate antiretroviral medications. Such reductions depend on multiple health system encounters during antenatal care (ANC), delivery and breastfeeding; in countries with limited access to care, transmission remains high. In Lesotho, where 28% of women attending ANC are HIV positive but where geographic and other factors limit access to ANC and facility deliveries, a Minimum PMTCT Package was launched in 2007 as an alternative to the existing facility-based approach. Distributed at the first ANC visit, it packaged together all necessary pregnancy, delivery and early postnatal antiretroviral medications for mother and infant.

Methods

To examine the availability, feasibility, acceptability and possible negative consequences of the Minimum PMTCT Package, data from a 2009 qualitative and quantitative study and a 2010 facility assessment were used. To examine the effects on ANC and facility-based delivery rates, a difference-in-differences analytic approach was applied to 2009 Demographic and Health Survey data for HIV-tested women who gave birth before and after Minimum PMTCT Package implementation.

Results

The Minimum PMTCT Package was feasible and acceptable to providers and clients. Problems with test kit and medicine stock-outs occurred, and 46% of women did not receive the Minimum PMTCT Package until at least their second ANC visit. Providing adequate instruction on the use of multiple medications represented a challenge. The proportion of HIV-positive women delivering in facilities declined after Minimum PMTCT Package implementation, although it increased among HIV-negative women (difference-in-differences=14.5%, p=0.05). The mean number of ANC visits declined more among HIV-positive women than among HIV-negative women after implementation, though the difference was not statistically significant (p=0.09). Changes in the percentage of women receiving≥4 ANC visits did not differ between the two groups.

Conclusions

If supply issues can be resolved and adequate client educational materials provided, take-away co-packages have the potential to increase access to PMTCT commodities in countries where women have limited access to health services. However, efforts must be made to carefully monitor potential changes in ANC visits and facility deliveries, and further evaluation of adherence, safety and effectiveness are needed.

Intrapartum single-dose carbamazepine reduces nevirapine levels faster and may decrease resistance after a single dose of nevirapine for perinatal HIV prevention

BACKGROUND

World Health Organization guidelines recommend zidovudine + lamivudine for 7 days from labor onset in HIV-infected women receiving single-dose nevirapine (sdNVP) to cover prolonged subtherapeutic nevirapine concentrations. Although effective, this is complicated and does not eliminate resistance; alternative strategies could add benefit.

METHODS

Antiretroviral-naive HIV-infected pregnant women aged 18-40 years, with CD4 >200 cells per cubic millimeter, able to regularly attend the antenatal clinics in Moshi, Tanzania, were enrolled 1:1 by alternate allocation to receive 200 mg sdNVP alone or in combination with open-label 400-mg single-dose carbamazepine (sdNVP/CBZ) at delivery (ClinicalTrials.gov NCT00294892). The coprimary outcomes were nevirapine plasma concentrations 1 week and nevirapine resistance mutations 6 weeks postpartum. Analyses were based on those still eligible at delivery.

RESULTS

Ninety-seven women were assigned to sdNVP and 95 to sdNVP/CBZ during pregnancy, of whom 75 sdNVP and 83 sdNVP/CBZ were still eligible at delivery at study sites. The median (interquartile range) nevirapine plasma concentration was 1.55 (0.88-1.84) mg/L in sdNVP (n = 61) and 1.40 (0.93-1.97) mg/L in sdNVP/CBZ (n = 72) at delivery (P = 0.91), but 1 week later was significantly lower in sdNVP/CBZ [n = 63; 0.09 (0.05-0.20) mg/L] than in sdNVP [n = 52; 0.20 (0.09-0.31) mg/L; rank-sum: P = 0.004] (geometric mean ratio: 0.64, 95% confidence interval: 0.43 to 0.96; P = 0.03). Six weeks postpartum, nevirapine mutations were observed in 11 of 52 (21%) in sdNVP and 6 of 55 (11%) in sdNVP/CBZ (odds ratio = 0.46, 95% confidence interval: 0.16 to 1.34; P = 0.15).

CONCLUSIONS

Addition of single-dose carbamazepine to sdNVP at labor onset in HIV-infected, pregnant women did not affect nevirapine plasma concentration at delivery, but significantly reduced it 1 week postpartum, with a trend toward fewer nevirapine resistance mutations.

Emergence of minor drug-resistant HIV-1 variants after triple antiretroviral prophylaxis for prevention of vertical HIV-1 transmission

BACKGROUND

WHO-guidelines for prevention of mother-to-child transmission of HIV-1 in resource-limited settings recommend complex maternal antiretroviral prophylaxis comprising antenatal zidovudine (AZT), nevirapine single-dose (NVP-SD) at labor onset and AZT/lamivudine (3TC) during labor and one week postpartum. Data on resistance development selected by this regimen is not available. We therefore analyzed the emergence of minor drug-resistant HIV-1 variants in Tanzanian women following complex prophylaxis.

METHOD

1395 pregnant women were tested for HIV-1 at Kyela District Hospital, Tanzania. 87/202 HIV-positive women started complex prophylaxis. Blood samples were collected before start of prophylaxis, at birth and 1-2, 4-6 and 12-16 weeks postpartum. Allele-specific real-time PCR assays specific for HIV-1 subtypes A, C and D were developed and applied on samples of mothers and their vertically infected infants to quantify key resistance mutations of AZT (K70R/T215Y/T215F), NVP (K103N/Y181C) and 3TC (M184V) at detection limits of <1%.

RESULTS

50/87 HIV-infected women having started complex prophylaxis were eligible for the study. All women took AZT with a median duration of 53 days (IQR 39-64); all women ingested NVP-SD, 86% took 3TC. HIV-1 resistance mutations were detected in 20/50 (40%) women, of which 70% displayed minority species. Variants with AZT-resistance mutations were found in 11/50 (22%), NVP-resistant variants in 9/50 (18%) and 3TC-resistant variants in 4/50 women (8%). Three women harbored resistant HIV-1 against more than one drug. 49/50 infants, including the seven vertically HIV-infected were breastfed, 3/7 infants exhibited drug-resistant virus.

CONCLUSION

Complex prophylaxis resulted in lower levels of NVP-selected resistance as compared to NVP-SD, but AZT-resistant HIV-1 emerged in a substantial proportion of women. Starting AZT in pregnancy week 14 instead of 28 as recommended by the current WHO-guidelines may further increase the frequency of AZT-resistance mutations. Given its impact on HIV-transmission rate and drug-resistance development, HAART for all HIV-positive pregnant women should be considered.

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.

Quantifying the impact of nevirapine-based prophylaxis strategies to prevent mother-to-child transmission of HIV-1: a combined pharmacokinetic, pharmacodynamic, and viral dynamic analysis to predict clinical outcomes

Single-dose nevirapine (sd-NVP) and extended NVP prophylaxis are widely used in resource-constrained settings to prevent vertical HIV-1 transmission. We assessed the pharmacokinetics of sd-NVP in 62 HIV-1-positive pregnant Ugandan woman and their newborns who were receiving sd-NVP prophylaxis to prevent mother-to-child HIV-1 transmission. Based on these data, we developed a mathematical model system to quantify the impact of different sd-NVP regimens at delivery and of extended infant NVP prophylaxis (6, 14, 21, 26, 52, 78, and 102 weeks) on the 2-year risk of HIV-1 transmission and development of drug resistance in mothers and their breast-fed infants. Pharmacokinetic parameter estimates and model-predicted HIV-1 transmission rates were very consistent with other studies. Predicted 2-year HIV-1 transmission risks were 35.8% without prophylaxis, 31.6% for newborn sd-NVP, 19.1% for maternal sd-NVP, and 19.7% for maternal/newborn sd-NVP. Maternal sd-NVP reduced newborn infection predominately by transplacental exchange, providing protective NVP concentrations to the newborn at delivery, rather than by maternal viral load reduction. Drug resistance was frequently selected in HIV-1-positive mothers after maternal sd-NVP. Extended newborn NVP prophylaxis further decreased HIV-1 transmission risks, but an overall decline in cost-effectiveness for increasing durations of newborn prophylaxis was indicated. The total number of infections with resistant virus in newborns was not increased by extended newborn NVP prophylaxis. The developed mathematical modeling framework successfully predicted the risk of HIV-1 transmission and resistance development and can be adapted to other drugs/drug combinations to a priori assess their potential in reducing vertical HIV-1 transmission and resistance spread.

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.

HIV-1-resistance-associated mutations after failure of first-line antiretroviral treatment among children in resource-poor regions: a systematic review

HIV-positive children are at high risk of drug resistance, which is of particular concern in settings where antiretroviral options are limited. In this Review we explore resistance rates and patterns among children in developing countries in whom antiretroviral treatment has failed. We did a systematic search of online databases and conference abstracts and included studies reporting HIV-1 drug resistance after failure of first-line paediatric regimens in children (<18 years) in resource-poor regions (Latin America, Africa, and Asia). We retrieved 1312 citations, of which 30 studies reporting outcomes in 3241 children were eligible. Viruses with resistance-associated mutations were isolated from 90% (95% CI 88-93%) of children. The prevalence of mutations associated with nucleoside reverse transcriptase inhibitors was 80%, with non-nucleoside reverse transcriptase inhibitors was 88%, and with protease inhibitors was 54%. Methods to prevent treatment failure, including adequate paediatric formulations and affordable salvage treatment options are urgently needed.

Pregnancy and virologic response to antiretroviral therapy in South Africa

BACKGROUND

Although women of reproductive age are the largest group of HIV-infected individuals in sub-Saharan Africa, little is known about the impact of pregnancy on response to highly active antiretroviral therapy (HAART) in that setting. We examined the effect of incident pregnancy after HAART initiation on virologic response to HAART.

METHODS AND FINDINGS

We evaluated a prospective clinical cohort of adult women who initiated HAART in Johannesburg, South Africa between 1 April 2004 and 30 September 2009, and followed up until an event, death, transfer, drop-out, or administrative end of follow-up on 31 March 2010. Women over age 45 and women who were pregnant at HAART initiation were excluded from the study; final sample size for analysis was 5,494 women. Main exposure was incident pregnancy, experienced by 541 women; main outcome was virologic failure, defined as a failure to suppress virus to ≤ 400 copies/ml by six months or virologic rebound >400 copies/ml thereafter. We calculated adjusted hazard ratios using marginal structural Cox proportional hazards models and weighted lifetable analysis to calculate adjusted five-year risk differences. The weighted hazard ratio for the effect of pregnancy on time to virologic failure was 1.34 (95% confidence limit [CL] 1.02, 1.78). Sensitivity analyses generally confirmed these main results.

CONCLUSIONS

Incident pregnancy after HAART initiation was associated with modest increases in both relative and absolute risks of virologic failure, although uncontrolled confounding cannot be ruled out. Nonetheless, these results reinforce that family planning is an essential part of care for HIV-positive women in sub-Saharan Africa. More work is needed to confirm these findings and to explore specific etiologic pathways by which such effects may operate.

Efavirenz-based combination antiretroviral therapy after peripartum single-dose nevirapine

Single-dose nevirapine (sdNVP) reduces mother-to-child HIV transmission, but induces NVP resistance and subsequent NVP-based combination antiretroviral therapy (cART) may fail. Some resistance mutations affect NVP more than efavirenz (EFV). We evaluated virological suppression of EFV-based cART in women after sdNVP. A retrospective analysis matched 107 women who had received sdNVP within the 24 months before cART (cases) with women who had never received sdNVP (controls). By total cohort (intention-to-continue treatment) at week 96, 65% of cases and 73% of controls had a viral load (VL) <400 copies/mL and 63% of cases and 64% of controls had VL <25 copies/mL. At weeks 48 and 96, women starting cART less than six months after sdNVP (n = 20) had VL <400 copies/mL of 90% and 75%, respectively compared with 90% and 70%, respectively, for controls. Overall 172 (80%) women reached week 96. EFV-based cART, in field conditions, was effective for women after sdNVP, even within six months of sdNVP.

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.

Population pharmacokinetics of nevirapine in HIV-1-infected pregnant women and their neonates

The aim of the present study was to describe the nevirapine (NVP) pharmacokinetics (PK) in pregnant women and their neonates and to evaluate the transplacental drug transfer and administration scheme for the prevention of mother-to-child transmission. Thirty-eight HIV-1-infected pregnant women were administered one tablet of NVP (200 mg) and two tablets of tenofovir-emtricitabine (Truvada) at the initiation of labor. Children were given NVP syrup (2 mg/kg of body weight) as a single dose (sdNVP) on the first day of life. By pair, NVP concentrations were measured in 11 maternal, 1 cord blood, and 2 neonatal plasma samples and analyzed by a population approach. A one-compartment model was used for mothers and neonates; the absorption rate constants for mothers and neonates were 0.95 h(-1) (intersubject variability, 111%) and 0.39 h(-1), respectively; the apparent elimination clearances were 1.42 liter·h(-1) (intersubject variability, 22%) and 0.035 liter·h(-1), respectively; and apparent volumes of distribution were 87.3 liters (intersubject variability, 25%) and 5.65 liters, respectively. An effect compartment was linked to maternal circulation by mother-to-cord and cord-to-mother rate constants of 1.10 h(-1) and 1.43 h(-1), respectively. Placental transfer, expressed as the fetal-to-maternal area under the curve ratio, was 75%. Neonates had a very long half-lives (110 h) compared to adults. In the 38 mothers, the simulated median individual predicted time during which the NVP concentration remained above the half-maximal inhibitory concentration (IC(50)) was 13.2 days (range, 12 to 19.2 days). Thus, the administration of tenofovir-emtricitabine for at least 3 weeks after delivery should be considered to prevent the emergence of resistant viruses. The neonate must receive sdNVP immediately after birth when the infant is born less than 30 min after maternal drug intake to keep NVP concentrations above the IC(50).

Minority variants of drug-resistant HIV

Minor drug-resistant variants exist in every patient infected with human immunodeficiency virus (HIV). Because these minority variants are usually present at very low levels, they cannot be detected and quantified using conventional genotypic and phenotypic tests. Recently, several assays have been developed to characterize these low-abundance drug-resistant variants in the large, genetically complex population that is present in every HIV-infected individual. The most important issue is what results generated by these assays can predict clinical or treatment outcomes and might guide the management of patients in clinical practice. Cutoff values for the detection of these low-abundance viral variants that predict an increased risk of treatment failure should be determined. These thresholds may be specific for each mutation and treatment regimen. In this review, we summarize the attributes and limitations of the currently available detection assays and review the existing information about both acquired and transmitted drug-resistant minority variants.

Immunological response to highly active antiretroviral therapy following treatment for prevention of mother to child transmission of HIV-1: a study in Côte d'Ivoire

Background

Information is currently limited on the long-term follow up of HIV-1 infected women who are on highly active antiretroviral therapy (HAART) that contains nevirapine and lamivudine and who were previously exposed to antiretroviral drugs for the prevention of mother to child transmission (PMTCT) of HIV.

Methods

We studied the 36-month immunological response to HAART in HIV-1 infected women in Côte d'Ivoire. The women were previously exposed to antiretroviral drug regimens for PMTCT, including single-dose nevirapine and/or short-course zidovudine with or without lamivudine. All HAART regimens included a non-nucleoside reverse transcriptase inhibitor.

Results

At 36 months: the median absolute increase in CD4+ T cell count was +359 cells/mm³ (IQR: 210-466) in 200 women who had undergone 36-month follow-up visits; +359 cells/mm³ (IQR: 222-491) in 88 women not exposed to PMTCT antiretrovirals; and +363 cells/mm³ (IQR: 200-464) in 112 women exposed to at least one antiretroviral PMTCT regimen. Overall, 49 (19.8%) of the 247 women who initiated HAART met the immunological failure criteria at least once during follow up. The overall probability of immunological failure was 0.08 (95% CI: 0.12-0.15) at 12 months, and 0.21 (95% CI: 0.16-0.27) at 36 months. No difference was observed according to the presence or absence of resistance mutations to nevirapine or lamivudine in women tested at four weeks postpartum. In addition, at 36 months, 23% of women were lost to follow up, dead or had stopped their treatment.

Conclusions

A non-nucleoside reverse transcriptase inhibitor-based antiretroviral regimen, initiated a year or more after PMTCT exposure and that includes nevirapine, remains a good option for at least the first 36 months of treatment.

Efficacy and safety of 1-month postpartum zidovudine-didanosine to prevent HIV-resistance mutations after intrapartum single-dose nevirapine

BACKGROUND

Intrapartum single-dose nevirapine plus third trimester maternal and infant zidovudine are essential components of programs to prevent mother-to-child transmission of human immunodeficiency virus (HIV) in resource-limited settings. The persistence of nevirapine in the plasma for 3 weeks postpartum risks selection of resistance mutations to nonnucleoside reverse-transcriptase inhibitors (NNRTIs). We hypothesized that a 1-month zidovudine-didanosine course initiated at the same time as single-dose nevirapine (sdNVP) would prevent the selection of nevirapine-resistance mutations.

METHODS

HIV-infected pregnant women in the PHPT-4 cohort with CD4 cell counts >250 cells/mm3 received antepartum zidovudine from the third trimester until delivery, sdNVP during labor, and a 1-month zidovudine-didanosine course after delivery. These women were matched on the basis of baseline HIV load, CD4 cell count, and duration of antepartum zidovudine to women who received sdNVP in the PHPT-2 trial (control subjects). Consensus sequencing and the more sensitive oligonucleotide ligation assay were performed on samples obtained on postpartum days 7-10, 37-45, and 120 (if the HIV load was >500 copies/mL) to detect K103N/Y181C/G190A mutations.

RESULTS

The 222 PHPT-4 subjects did not differ from matched control subjects in baseline characteristics except for age. The combined group median CD4 cell count was 421 cells/mm3 (interquartile range [IQR], 322-549 cells/mm3), the median HIV load was 3.45 log10 copies/mL (IQR, 2.79-4.00 log10 copies/mL), and the median duration of zidovudine prophylaxis was 10.4 weeks (IQR, 9.1-11.4 weeks). Using consensus sequencing, major NNRTI resistance mutations were detected after delivery in 0% of PHPT-4 subjects and 10.4% of PHPT-2 controls. The oligonucleotide ligation assay detected resistance in 1.8% of PHPT-4 subjects and 18.9% of controls. Major NNRTI resistance mutations were detected by either method in 1.8% of PHPT-4 subjects and 20.7% of controls (P < .001).

CONCLUSIONS

A 1-month postpartum course of zidovudine plus didanosine prevented the selection of the vast majority of NNRTI resistance mutations.

Effectiveness of non-nucleoside reverse-transcriptase inhibitor-based antiretroviral therapy in women previously exposed to a single intrapartum dose of nevirapine: a multi-country, prospective cohort study

BACKGROUND

Intrapartum and neonatal single-dose nevirapine (NVP) reduces the risk of mother-to-child HIV transmission but also induces viral resistance to non-nucleoside reverse transcriptase inhibitor (NNRTI) drugs. This drug resistance largely fades over time. We hypothesized that women with a prior single-dose NVP exposure would have no more than a 10% higher cumulative prevalence of failure of their NNRTI-containing antiretroviral therapy (ART) over the first 48 wk of therapy than would women without a prior exposure.

METHODS AND FINDINGS

We enrolled 355 NVP-exposed and 523 NVP-unexposed women at two sites in Zambia, one site in Kenya, and two sites in Thailand into a prospective, non-inferiority cohort study and followed them for 48 wk on ART. Those who died, discontinued NNRTI-containing ART, or had a plasma viral load >or=400 copies/ml at either the 24 wk or 48 wk study visits and confirmed on repeat testing were characterized as having failed therapy. Overall, 114 of 355 NVP-exposed women (32.1%) and 132 of 523 NVP-unexposed women (25.2%) met criteria for treatment failure. The difference in failure rates between the exposure groups was 6.9% (95% confidence interval [CI] 0.8%-13.0%). The failure rates of women stratified by our predefined exposure interval categories were as follows: 47 of 116 women in whom less than 6 mo elapsed between exposure and starting ART failed therapy (40%; p<0.001 compared to unexposed women); 25 of 67 women in whom 7-12 mo elapsed between exposure and starting ART failed therapy (37%; p = 0.04 compared to unexposed women); and 42 of 172 women in whom more than 12 mo elapsed between exposure and starting ART failed therapy (24%; p = 0.82 compared to unexposed women). Locally weighted regression analysis also indicated a clear inverse relationship between virologic failure and the exposure interval.

CONCLUSIONS

Prior exposure to single-dose NVP was associated with an increased risk of treatment failure; however, this risk seems largely confined to women with a more recent exposure. Women requiring ART within 12 mo of NVP exposure should not be prescribed an NNRTI-containing regimen as first-line therapy.

Universal antiretroviral therapy for pregnant and breast-feeding HIV-1-infected women: towards the elimination of mother-to-child transmission of HIV-1 in resource-limited settings

Prevention of mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV-1) remains a challenge in most resource-limited settings, particularly in Africa. Single-dose and short-course antiretroviral (ARV) regimens are only partially effective and have failed to achieve wide coverage despite their apparent simplicity. More potent ARV combinations are restricted to pregnant women who need treatment for themselves and are also infrequently used. Furthermore, postnatal transmission via breast-feeding is a serious additional threat. Modifications of infant feeding practices aim to reduce HIV-1 transmission through breast milk; replacement feeding is neither affordable nor safe for the majority of African women, and early breast-feeding cessation (eg, prior to 6 months of life) requires substantial care and nutritional counseling to be practiced safely. The recent roll out of ARV treatment has changed the paradigm of prevention of MTCT. To date, postnatal ARV interventions that have been evaluated target either maternal ARV treatment to selected breast-feeding women, with good efficacy, or single-drug postexposure prophylaxis for short periods of time to their neonates, with a partial efficacy and at the expense of acquisition of drug-related viral resistance. We hypothesize that a viable solution to eliminate pediatric AIDS lies in the universal provision of fully suppressive ARV regimens to all HIV-1-infected women through pregnancy, delivery, and the entire breast-feeding period. On the basis of available evidence, we suggest translating into practice the recently available evidence on this matter without any further delay.

Postpartum antiretroviral drug resistance in HIV-1-infected women receiving pregnancy-limited antiretroviral therapy

BACKGROUND

Pregnancy-limited antiretroviral therapy (PLAT) drastically reduces HIV-1 transmission to the newborn, but may select for antiretroviral drug resistance mutations in mothers.

METHODS

We evaluated antiretroviral-naive, HIV-1-infected pregnant women who received PLAT between 1998 and 2005, and had 2-month or 6-month postpartum plasma samples available with HIV-1 RNA levels more than 500 copies/ml. Postpartum drug resistance mutation rates were assessed blindly using population sequencing and allele-specific PCR (ASPCR) of the M184V, K103N and D30N mutations. Factors associated with selection of drug resistance mutations were investigated.

RESULTS

One hundred and forty-six women were included. All women received zidovudine and lamivudine during pregnancy; 76% also received nelfinavir and 8.2% nevirapine. Resistance data were available from 114 women (78%). Postpartum rates of single-class, dual-class, and triple-class resistance were, respectively, 43, 6.1 and 0% (63.2, 10.5 and 1.7% by ASPCR). In women receiving dual or triple PLAT, respectively, postpartum M184V/I rates were 65% (95% by ASPCR) and 28.7% (51.6% by ASPCR), respectively (P < 0.01). Postpartum nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance rates among women receiving nevirapine were 25% for K103N (37.5% by ASPCR) and 12.5% for Y188C. Protease inhibitor resistance rates in women receiving nelfinavir were 1.1% for D30N (1.1% by ASPCR) and 1.1% for L90M. Dual versus triple PLAT and prolonged zidovudine exposure were associated with selection of M184V. Nevirapine use and length of zidovudine and lamivudine exposure were associated with selection of K103N.

CONCLUSION

PLAT is associated with frequent selection of resistance to drugs with low-genetic barrier. Triple-drug PLAT decreases the odds for M184V selection. Routine postpartum genotypic resistance testing may be useful to guide future treatment decisions in mothers.

Successes, challenges, and limitations of current antiretroviral therapy in low-income and middle-income countries

As a result of the scale-up of antiretroviral treatment (ART) programmes and substantial financial support worldwide, an increasing number of HIV-infected individuals in low-income and middle-income countries (LIMCs) now have access to ART. Despite this progress, important questions remain on the best use of ART and how patients should be maintained on a successful regimen. This Review addresses some of the issues faced by those managing the epidemic in LMICs, including when to start treatment, choice of first-line ART, and when to switch regimens. Although the first priority must be continued expansion of access to ART, there should be a move towards starting ART earlier to treat individuals before they reach advanced stages of disease, to reduce early mortality, and to build support for improved monitoring of treatment failure. There is also a need for more randomised controlled studies to identify the long-term outcomes, cost-effectiveness of ART, and use of virological monitoring in LMICs.

Response to nonnucleoside reverse transcriptase inhibitor-based therapy in HIV-infected children with perinatal exposure to single-dose nevirapine

We set out to investigate whether there are clinically significant consequences when children with perinatal exposure to single-dose nevirapine are initiated on a nonnucleoside reverse transcriptase inhibitor (NNRTI) containing a highly active antiretroviral therapy (HAART) regimen. We carried out a chart and database review of 104 HIV-infected children, who had initiated HAART with an NNRTI at JCRC and were less than or equal to 5 years of age, 35 (33.7%) of whom had prior exposure to perinatal single-dose nevirapine. We studied the viral load and CD4 percentage at baseline, at week 24, and at week 48 after the start of HAART in children exposed and not exposed to perinatal single-dose nevirapine, as well as the results of genotypic resistance testing done for the children who had failed to achieve virologic suppression on HAART. At weeks 24 and 48 after initiating HAART, children not exposed to single-dose nevirapine were 3.28 times [OR = 3.28, 95% CI: (1.37 to 9.20), p = 0.0167] and 3.47 times [OR = 3.47, 95% CI: (1.28 to 9.37), p = 0.0091] more likely to achieve virologic suppression compared to children exposed to single-dose nevirapine, respectively. However, the CD4 cell response at weeks 24 and 48 was not worse in the children exposed to single-dose nevirapine. In 10 children with perinatal exposure to single-dose nevirapine, NNRTI resistance mutations, mostly K103N, Y181C, and G109A, were identified. HIV-infected children with perinatal exposure to single-dose nevirapine are less likely to achieve short-term virologic suppression when started on an NNRTI-containing regimen, when compared to those who were not exposed to it, probably because the exposure predisposes them to developing NNRTI resistance mutations.

Prevention of human immunodeficiency virus mother-to-child transmission in Israel

The objective of the study was to investigate the HIV-mother-to-child transmission (MTCT) rate in Israel. This was a retrospective study of HIV-infected pregnant women, mainly immigrants from Ethiopia, in six Israeli AIDS centres, in 2000-2005. Medical records of mothers and newborns were evaluated for HIV status, treatment and MTCT rates. Three hundred pregnancies of 241 HIV-infected women, resulting in 304 live births, were studied. In 86/241(36%) women, HIV diagnosis was made during the current pregnancy or shortly after labour. Thirty others were diagnosed during previous pregnancies. Highly active antiretroviral therapy (HAART) was prescribed in 76% of pregnancies. The mean viral load before labour was 23,000 +/- 100,000 copies/mL with a mean CD4 of 406 +/- 223 (range 4-1277) cells/mm(3). Caesarian sections were preformed in 175/300 pregnancies (103/175 with viral load <1000 copies/mL). During labour, azidothymidine (AZT) was given to 80% and nevirapine to 8% of the women. Eighty-eight percent of the neonates received AZT for six weeks. The overall HIV-MTCT rate was 3.6%. MTCT correlated significantly with delayed HIV diagnosis, low CD4, lack of HAART during pregnancy and lack of perinatal treatment. HIV treatment of mothers and their newborns throughout pregnancy, labour and perinatal period are crucial for effective prevention of MTCT, emphasizing the need for early HIV screening, diagnosis and treatment.

Antiretroviral medications during pregnancy for therapy or prophylaxis

The use of combination antiretroviral therapy during pregnancy has enabled us to decrease perinatal HIV transmission to less than 1%, in areas with adequate resources. Questions remain regarding the safety of these medications for the mother, fetus, and child. Recent publications present conflicting data about associations between antiretrovirals and prematurity and other adverse pregnancy outcomes, and if highly active antiretroviral therapy (HAART) is necessary for all pregnant women. The pharmacokinetics of some antiretroviral medications are altered significantly during pregnancy; placental transfer to the fetus is variable. The well-documented benefit of HAART for preventing mother-to-child transmission generally outweighs the potential risks to the fetus, infant, and mother. However, potential adverse effects are of concern, and questions remain as to the optimal treatment strategy. More data on the effects of antiretrovirals during pregnancy are needed.

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.

Progress in prevention of mother-to-child transmission of HIV infection in Ukraine: results from a birth cohort study

Background

Ukraine was the epicentre of the HIV epidemic in Eastern Europe, which has the most rapidly accelerating HIV epidemic world-wide today; national HIV prevalence is currently estimated at 1.6%. Our objective was to evaluate the uptake and effectiveness of interventions for prevention of mother-to-child transmission (PMTCT) over an eight year period within operational settings in Ukraine, within the context of an ongoing birth cohort study.

Methods

The European Collaborative Study (ECS) is an ongoing birth cohort study in which HIV-infected pregnant women identified before or during pregnancy or at delivery were enrolled and their infants prospectively followed. Three centres in Ukraine started enrolling in 2000, with a further three joining in September 2006.

Results

Of the 3356 women enrolled, 21% (689) reported current or past injecting drug use (IDU). Most women were diagnosed antenatally and of those, the proportion diagnosed in the first/second trimester increased from 47% in 2000/01 (83/178) to 73% (776/1060) in 2006/07 (p < 0.001); intrapartum diagnosis was associated with IDU (Adjusted odds ratio 4.38; 95%CI 3.19–6.02). The percentage of women not receiving any antiretroviral prophylaxis declined from 18% (36/205) in 2001 to 7% in 2007 (61/843) (p < 0.001). Use of sdNVP alone substantially declined after 2003, with a concomitant increase in zidovudine prophylaxis. Median antenatal zidovudine prophylaxis duration increased from 24 to 72 days between 2000 and 2007. Elective caesarean section (CS) rates were relatively stable over time and 34% overall. Mother-to-child transmission (MTCT) rates decreased from 15.2% in 2001 (95%CI 10.2–21.4) to 7.0% in 2006 (95%CI 2.6–14.6). In adjusted analysis, MTCT risk was reduced by 43% with elective CS versus vaginal delivery and by 75% with zidovudine versus no prophylaxis.

Conclusion

There have been substantial improvements in use of PMTCT interventions in Ukraine, including earlier diagnosis of HIV-infected pregnant women and increasing coverage with antiretroviral prophylaxis and the initial MTCT rate has more than halved. Future research should focus on hard-to-reach populations such as IDU and on missed opportunities for further reducing the MTCT rate.

Preventing mother-to-child transmission of HIV in resource-limited settings

Mother-to-child transmission (MTCT) before, during and after delivery may result in the acquisition of HIV for 30–35% of infants of HIV-infected mothers. Peripartum HIV transmission can be reduced to under 5% in resource-limited settings using a feasible prophylactic antiretroviral regimen. Reducing postnatal transmission through breastfeeding, whilst maintaining child survival, is an urgent priority, given that breastfeeding causes one-third to one-half of all infant HIV infections. Recent evidence highlights the impact of breastfeeding duration and pattern, and hazards associated with the avoidance of breastfeeding in different settings. New international guidelines on HIV and infant feeding have been published. Despite knowledge of how to reduce MTCT of HIV in resource-poor settings, an unacceptably low proportion of women access prevention of MTCT services (PMTCT); follow-up of women and children is poor. To improve survival of mothers and children, health services need to be strengthened, with the integration of PMTCT into existing maternal and child health services.

Antiretroviral drug resistance testing in adult HIV-1 infection: 2008 recommendations of an International AIDS Society-USA panel

Resistance to antiretroviral drugs remains an important limitation to successful human immunodeficiency virus type 1 (HIV-1) therapy. Resistance testing can improve treatment outcomes for infected individuals. The availability of new drugs from various classes, standardization of resistance assays, and the development of viral tropism tests necessitate new guidelines for resistance testing. The International AIDS Society-USA convened a panel of physicians and scientists with expertise in drug-resistant HIV-1, drug management, and patient care to review recently published data and presentations at scientific conferences and to provide updated recommendations. Whenever possible, resistance testing is recommended at the time of HIV infection diagnosis as part of the initial comprehensive patient assessment, as well as in all cases of virologic failure. Tropism testing is recommended whenever the use of chemokine receptor 5 antagonists is contemplated. As the roll out of antiretroviral therapy continues in developing countries, drug resistance monitoring for both subtype B and non-subtype B strains of HIV will become increasingly important.