Higher Transplacental Pathogen-Specific Antibody Transfer Among Pregnant Women Randomized to Triple Antiretroviral Treatment Versus Short Course Zidovudine.

BACKGROUND: HIV-1 infection may impair transplacental antibody transfer to infants. The impact of highly active antiretroviral treatment (ART) given during pregnancy on transplacental antibody transport is unknown. METHODS: HIV-1 infected pregnant women with CD4 counts between 200 - 500 were randomized to short-course zidovudine (ZDV) or triple ART at 32 weeks gestation for prevention of mother-to-child HIV-1 transmission. Levels of maternal antibody against measles, pneumococcus and rotavirus at delivery, and antibody transfer to the baby through cord blood, were compared between trial arms. RESULTS: Overall, 141 and 148 women were randomized to triple ART and ZDV, respectively; cord blood was available for a subset (n = 20 in triple ART and n = 22 in ZDV). Maternal antibody levels to all pathogens during pregnancy and at delivery were not significantly different between arms. Within each arm, antibody levels at delivery were lower than at enrolment. For all antibodies, a woman's levels before delivery were an important predictor of amount transferred to her infant. Women on triple ART transferred higher levels of pathogen-specific antibodies when compared with women on short course ZDV. CONCLUSIONS: Women on triple ART transferred higher levels of pathogen-specific antibodies compared with women on ZDV alone.

Early infant feeding patterns and HIV-free survival: findings from the Kesho-Bora trial (Burkina Faso, Kenya, South Africa).

OBJECTIVE: To investigate the association between feeding patterns and HIV-free survival in children born to HIV-infected mothers and to clarify whether antiretroviral (ARV) prophylaxis modifies the association. METHODS: From June 2005 to August 2008, HIV-infected pregnant women were counseled regarding infant feeding options, and randomly assigned to triple-ARV prophylaxis (triple ARV) until breastfeeding cessation (BFC) before age 6 months or antenatal zidovudine with single-dose nevirapine (short-course ARV). Eighteen-month HIV-free survival of infants HIV-negative at 2 weeks of age was assessed by feeding patterns (replacement feeding from birth, BFC <3 months, BFC ≥3 months). RESULTS: Of the 753 infants alive and HIV-negative at 2 weeks, 28 acquired infection and 47 died by 18 months. Overall HIV-free survival at 18 months was 0.91 [95% confidence interval (CI): 0.88-0.93]. In the short-course ARV arm, HIV-free survival (0.88; CI: 0.84-0.91) did not differ by feeding patterns. In the triple ARV arm, overall HIV-free survival was 0.93 (CI: 0.90-0.95) and BFC <3 months was associated with lower HIV-free survival than BFC ≥3 months (adjusted hazard ratio: 0.36; CI: 0.15-0.83) and replacement feeding (adjusted hazard ratio: 0.20; CI: 0.04-0.94). In the triple ARV arm, 4 of 9 transmissions occurred after reported BFC (and 5 of 19 in the short-course arm), indicating that some women continued breastfeeding after interruption of ARV prophylaxis. CONCLUSIONS: In resource-constrained settings, early weaning has previously been associated with higher infant mortality. We show that, even with maternal triple-ARV prophylaxis during breastfeeding, early weaning remains associated with lower HIV-free survival, driven in particular by increased mortality.

Morbidity in relation to feeding mode in African HIV-exposed, uninfected infants during the first 6 mo of life: the Kesho Bora study.

BACKGROUND: Refraining from breastfeeding to prevent HIV transmission has been associated with increased morbidity and mortality in HIV-exposed African infants. OBJECTIVE: The objective was to assess risks of common and serious infectious morbidity by feeding mode in HIV-exposed, uninfected infants ≤6 mo of age with special attention to the issue of reverse causality. DESIGN: HIV-infected pregnant women from 5 sites in Burkina Faso, Kenya, and South Africa were enrolled in the prevention of mother-to-child transmission Kesho Bora trial and counseled to either breastfeed exclusively and cease by 6 mo postpartum or formula feed exclusively. Maternal-reported morbidity (fever, diarrhea, and vomiting) and serious infectious events (SIEs) (gastroenteritis and lower respiratory tract infections) were investigated for 751 infants for 2 age periods (0-2.9 and 3-6 mo) by using generalized linear mixed models with breastfeeding as a time-dependent variable and adjustment for study site, maternal education, economic level, and cotrimoxazole prophylaxis. RESULTS: Reported morbidity was not significantly higher in nonbreastfed compared with breastfed infants [OR: 1.31 (95% CI: 0.97, 1.75) and 1.21 (0.90, 1.62) at 0-2.9 and 3-6 mo of age, respectively]. Between 0 and 2.9 mo of age, never-breastfed infants had increased risks of morbidity compared with those of infants who were exclusively breastfed (OR: 1.49; 95% CI: 1.01, 2.2; P = 0.042). The adjusted excess risk of SIEs in nonbreastfed infants was large between 0 and 2.9 mo (OR: 6.0; 95% CI: 2.2, 16.4; P = 0.001). Between 3 and 6 mo, the OR for SIEs was sensitive to the timing of breastfeeding status, i.e., 4.3 (95% CI: 1.2, 15.3; P = 0.02) when defined at end of monthly intervals and 2.0 (95% CI: 0.8, 5.0; P = 0.13) when defined at the beginning of intervals. Of 52 SIEs, 3 mothers reported changes in feeding mode during the SIE although none of the mothers ceased breastfeeding completely. CONCLUSIONS: Not breastfeeding was associated with increased risk of serious infections especially between 0 and 2.9 mo of age. The randomized controlled trial component of the Kesho Bora study was registered at Current Controlled Trials (www.controlled-trials.com) as ISRCTN71468401.

Postpartum weight change among HIV-infected mothers by antiretroviral prophylaxis and infant feeding modality in a research setting.

OBJECTIVE: To assess the relationship between infant feeding, triple-antiretroviral prophylaxis and weight from 2 weeks (baseline) to 6 months postpartum among HIV-infected mothers in a mother-to-child transmission (MTCT) of HIV-prevention trial in five sub-Saharan African sites. METHODS: HIV-infected pregnant women with CD4 cell counts of 200-500 cells/µl were counselled to choose breastfeeding to 6 months or replacement feeding from delivery. They were randomized to receive perinatal zidovudine and single-dose nevirapine or triple-antiretroviral MTCT prophylaxis until breastfeeding cessation. Mixed-effect linear models were used to compare maternal weight trajectories over time by infant feeding mode. Antiretroviral prophylaxis and BMI at baseline were examined as potential effect modifiers. RESULTS: Among 797 mothers, 620 (78%) initiated breastfeeding. Wasting (BMI <18.5) was rare at baseline (2%), whereas overweight/obesity (BMI ≥ 25) was common (40%). In the model including all women, breastfeeding was not associated with weight loss up to 6 months, irrespective of baseline BMI and antiretroviral prophylaxis. Triple-antiretroviral prophylaxis was associated with weight gain among replacement-feeding mothers with baseline BMI at least 25 (+0.54 kg/month; P < 0.0001). In the model including breastfeeding mothers only, triple-antiretroviral prophylaxis was associated with weight gain among mothers with baseline BMI at least 25 who ceased breastfeeding before 3 months postpartum (+0.33 kg/month; P = 0.03). CONCLUSION: The results suggest that breastfeeding up to 6 months postpartum is not detrimental for postpartum weight among well nourished HIV-infected mothers at intermediate-disease stage. In the absence of breastfeeding or after weaning, triple-antiretroviral prophylaxis is associated with weight gain among women with high BMI, even after cessation of prophylaxis.

Relationship between mortality and feeding modality among children born to HIV-infected mothers in a research setting: the Kesho Bora study.

OBJECTIVE: To assess the relationship between infant feeding practices and mortality by 18 months of age among children born to HIV-infected mothers in the Kesho Bora trial (Burkina-Faso, Kenya and South Africa). METHODS: Enrolled HIV-infected women were counseled to choose between breastfeeding up to 6 months or replacement feeding from delivery. Multivariable Cox models were used to compare the infant mortality risks according to feeding practices over time defined as never breastfed, weaned or still breastfed. The category 'still breastfed' was disaggregated as exclusively, predominantly or partially breastfed to compare modes of breastfeeding. The relationship between weaning and mortality was also assessed using marginal structural models to control for time-dependent confounders, such as maternal or infant morbidity (reverse causality). RESULTS: Among 795 mothers, 618 (77.7%) initiated breastfeeding. Mortality rates by 18 months among uninfected and infected children were 6 and 38%, respectively. Never breastfed and weaned children were at greater risk of death compared with those still breastfed. Adjusted hazard ratios were 6.7 [95% confidence interval (CI)=2.5-17.9; P<0.001] and 6.9 (CI=2.8-17.2; P<0.001) for never breastfed and weaned children, respectively. Estimation of the effect of weaning using marginal structural models led to similar results. No statistically significant differences were observed according to mode of breastfeeding (exclusive, predominant or partial). CONCLUSION: Within 6 months after birth, weaned or never breastfed children were at about seven-fold higher risk of dying compared with children who were still breastfed despite a context in which interventions were provided to reduce risks associated with replacement feeding.

Infant feeding modes and determinants among HIV-1-infected African Women in the Kesho Bora Study.

OBJECTIVE: To assess breastfeeding modes and determinants in a prevention of mother-to-child transmission study. DESIGN: HIV-1-infected pregnant women from 5 sites in Burkina Faso, Kenya, and South Africa were enrolled in the study that comprised 2 prospective cohorts and 1 randomized controlled trial. Women were counseled to either breastfeed exclusively up to 6 months or formula feed from birth. METHODS: Determinants of breastfeeding initiation and continuation by 3 months postpartum were investigated using multiple logistic regression analysis. Neonatal morbidity was defined as mother-reported fever, diarrhea, or vomiting during the first month of life. RESULTS: Among 1028, 781 women (76%) initiated breastfeeding and 565 of 995 (56%) were still breastfeeding at 3 months postpartum (30% exclusively, 18% predominantly, and 8% partially). Study site (Durban, Mombasa, and Nairobi compared with Bobo-Dioulasso), CD4 cell count (<200 cells/mm), secondary schooling (compared with none), and emergency cesarean delivery (compared with vaginal delivery) were independently associated with a lower probability of ever breastfeeding. The odds of still breastfeeding by 3 months postpartum (among those breastfeeding by 1 month) were lower in Mombasa, Nairobi, and Somkhele (compared with Bobo-Dioulasso) and among infants with neonatal morbidity [0.60 (0.37-0.976)]. The odds of exclusive breastfeeding (EBF) by 3 months (if EBF by 1 month) were lower in Mombasa and Nairobi, in ill neonates [0.54 (0.31-0.93)] and boys [0.51 (0.34-0.77)]. CONCLUSIONS: EBF was of short duration, particularly for boys. The importance of neonatal morbidity for breastfeeding cessation requires further investigation. Infant feeding counseling might need adaptation to better support mothers of boys and ill neonates.

Triple antiretroviral compared with zidovudine and single-dose nevirapine prophylaxis during pregnancy and breastfeeding for prevention of mother-to-child transmission of HIV-1 (Kesho Bora study): a randomised controlled trial.

BACKGROUND: Breastfeeding is essential for child health and development in low-resource settings but carries a significant risk of transmission of HIV-1, especially in late stages of maternal disease. We aimed to assess the efficacy and safety of triple antiretroviral compared with zidovudine and single-dose nevirapine prophylaxis in pregnant women infected with HIV. METHODS: Pregnant women with WHO stage 1, 2, or 3 HIV-1 infection who had CD4 cell counts of 200-500 cells per µL were enrolled at five study sites in Burkina Faso, Kenya, and South Africa to start study treatment at 28-36 weeks' gestation. Women were randomly assigned (1:1) by a computer generated random sequence to either triple antiretroviral prophylaxis (a combination of 300 mg zidovudine, 150 mg lamivudine, and 400 mg lopinavir plus 100 mg ritonavir twice daily until cessation of breastfeeding to a maximum of 6·5 months post partum) or zidovudine and single-dose nevirapine (300 mg zidovudine twice daily until delivery and a dose of 600 mg zidovudine plus 200 mg nevirapine at the onset of labour and, after a protocol amendment in December, 2006, 1 week post-partum zidovudine 300 mg twice daily and lamivudine 150 mg twice daily). All infants received a 0·6 mL dose of nevirapine at birth and, from December, 2006, 4 mg/kg twice daily of zidovudine for 1 week after birth. Patients and investigators were not masked to treatment. The primary endpoints were HIV-free infant survival at 6 weeks and 12 months; HIV-free survival at 12 months in infants who were ever breastfed; AIDS-free survival in mothers at 18 months; and serious adverse events in mothers and babies. Analysis was by intention to treat. This trial is registered with Current Controlled Trials, ISRCTN71468401. FINDINGS: From June, 2005, to August, 2008, 882 women were enrolled, 824 of whom were randomised and gave birth to 805 singleton or first, liveborn infants. The cumulative rate of HIV transmission at 6 weeks was 3·3% (95% CI 1·9-5·6%) in the triple antiretroviral group compared with 5·0% (3·3-7·7%) in the zidovudine and single-dose nevirapine group, and at 12 months was 5·4% (3·6-8·1%) in the triple antiretroviral group compared with 9·5% (7·0-12·9%) in the zidovudine and single-dose nevirapine group (p=0·029). The cumulative rate of HIV transmission or death at 12 months was 10·2% (95% CI 7·6-13·6%) in the triple antiretroviral group compared with 16·0% (12·7-20·0%) in the zidovudine and single-dose nevirapine group (p=0·017). In infants whose mothers declared they intended to breastfeed, the cumulative rate of HIV transmission at 12 months was 5·6% (95% CI 3·4-8·9%) in the triple antiretroviral group compared with 10·7% (7·6-14·8%) in the zidovudine and single-dose nevirapine group (p=0·02). AIDS-free survival in mothers at 18 months will be reported in a different publication. The incidence of laboratory and clinical serious adverse events in both mothers and their babies was similar between groups. INTERPRETATION: Triple antiretroviral prophylaxis during pregnancy and breastfeeding is safe and reduces the risk of HIV transmission to infants. Revised WHO guidelines now recommend antiretroviral prophylaxis (either to the mother or to the baby) during breastfeeding if the mother is not already receiving antiretroviral treatment for her own health. FUNDING: Agence nationale de recherches sur le sida et les hépatites virales, Department for International Development, European and Developing Countries Clinical Trials Partnership, Thrasher Research Fund, Belgian Directorate General for International Cooperation, Centers for Disease Control and Prevention, Eunice Kennedy Shriver National Institute of Child Health and Human Development, and UNDP/UNFPA/World Bank/WHO Special Programme of Research, Development and Research Training in Human Reproduction.

Prevention of human immunodeficiency virus-1 transmission to the infant through breastfeeding: new developments.

Breastfeeding accounts for up to half of all infant human immunodeficiency virus (HIV) infections worldwide and carries an estimated transmission risk of about 15% when continued into the second year of life. Because replacement feeding is not safely available, culturally acceptable, or affordable in many parts of the world and because breastfeeding provides protection against other causes of infant mortality, approaches that reduce breastfeeding mother-to child transmission of HIV are being explored. These include exclusive breastfeeding for the infant's first few months of life followed by rapid weaning, treatments of expressed milk to inactivate the virus, and antiretroviral prophylaxis taken by the infant or mother during breastfeeding, which are strategies currently being tested in clinical trials. Passive (antibodies) and active (vaccine) immunoprophylaxis will also soon begin to be tested. This paper focuses on current and planned research on strategies to prevent breastfeeding transmission of HIV.

Use of antiretroviral drugs to prevent HIV-1 transmission through breast-feeding: from animal studies to randomized clinical trials.

The major remaining challenge in the prevention of mother-to-child transmission is the reduction of the risk in settings where breast-feeding is common. This review gives an update on ongoing or planned antiretroviral intervention studies in resource-limited settings that are aimed at reducing the risk of mother-to-infant HIV transmission during lactation. These strategies include antiretroviral therapy given to the mother to reduce viral load in plasma and breast milk as well as antiretroviral regimens providing prophylaxis to uninfected infants during the period of breast-feeding. The rationale for the interventions based on animal models and human studies is described as well as the study designs of clinical trials. Potential risks and benefits of these interventions to mothers and infants are also highlighted. Laboratory studies nested within several of these trials will provide a better understanding of the pathogenesis of postnatal HIV transmission and its potential prevention using antiretroviral drugs.