RESUMEN
BACKGROUND: Transmission through breastfeeding accounts for more than half of the unacceptably high number of new paediatric HIV infections worldwide. We hypothesised that, in addition to maternal antiretroviral therapy (ART), extended postnatal prophylaxis with lamivudine, guided by point-of-care assays for maternal viral load, could reduce postnatal transmission. METHODS: We did a phase 3, open-label, randomised controlled trial at four health-care facilities in Zambia and four health-care facilities in Burkina Faso. Mothers with HIV and their breastfed infants without HIV attending the second visit of the Expanded Programme of Immunisation (EPI-2; infant age 6-8 weeks) were randomly assigned 1:1 to intervention or control groups. In the intervention group, maternal viral load was measured using Xpert HIV viral load assay at EPI-2 and at 6 months, with results provided immediately. Infants whose mothers had a viral load of 1000 copies per mL or higher were started on lamivudine syrup twice per day for 12 months or 1 month after breastfeeding discontinuation. The control group followed national guidelines for prevention of postnatal transmission of HIV. The primary outcome assessed by modified intention to treat was infant HIV infection at age 12 months, with HIV DNA point-of-care testing at 6 months and at 12 months. This trial is registered with ClinicalTrials.gov (NCT03870438). FINDINGS: Between Dec 12, 2019 and Sept 30, 2021, 34 054 mothers were screened for HIV. Among them, 1506 mothers with HIV and their infants without HIV, including 1342 mother and infant pairs from Zambia and 164 from Burkina Faso, were eligible and randomly assigned 1:1 to the intervention (n=753) or control group (n=753). At baseline, the median age of the mothers was 30·6 years (IQR 26·0-34·7), 1480 (98·4%) of 1504 were receiving ART, and 169 (11·5%) of 1466 had a viral load ≥1000 copies/mL. There was one case of HIV transmission in the intervention group and six in the control group, resulting in a transmission incidence of 0·19 per 100 person-years (95% CI 0·005-1·04) in the intervention group and 1·16 per 100 person-years (0·43-2·53) in the control group, which did not reach statistical significance (p=0·066). HIV-free survival and serious adverse events were similar in both groups. INTERPRETATION: Our intervention, initiated at EPI-2 and based on extended single-drug postnatal prophylaxis guided by point-of-care maternal viral load could be an important strategy for paediatric HIV elimination. FUNDING: The EDCTP2 programme with the support of the UK Department of Health & Social Care.
Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adulto , Femenino , Humanos , Lactante , Fármacos Anti-VIH/uso terapéutico , Burkina Faso , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Infecciones por VIH/epidemiología , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Lamivudine/uso terapéutico , Madres , Zambia/epidemiologíaRESUMEN
OBJECTIVE: Our study aimed to assess the PMTCT indicators in Burkina Faso and Zambia using a patient-orientated innovative strategy based on the second visit in the Expanded Program on Immunization (EPI-2) visit at 6-8âweeks. DESIGN: This was a cross sectional study. METHODS: We assessed women attending EPI-2 at primary healthcare facilities in Burkina Faso and Zambia with their children about their exposure to PMTCT interventions. For women living with HIV (WLHIV), viral load was measured and their children were tested for HIV DNA using point of care devices. RESULTS: Overall, 25â093 were enrolled from Burkina Faso and 8961 women from Zambia. Almost, all women attended at least one antenatal care visit. Among those aware of their HIV-positive status, 95.8 and 99.2% were on antiretroviral therapy (ART) in Burkina Faso and Zambia, respectively. Among WLHIV on ART, 75 and 79.2% achieved a viral load suppression (viral load <1000âcopies/ml) in Burkina Faso and Zambia, respectively. Infant postnatal prophylaxis was administered from birth until EPI-2 to 60.9 and 89.7% of HIV-exposed children in Burkina Faso and Zambia, respectively. In Burkina Faso, only 60 of 192 (31.3%) of HIV-exposed children were sampled at day 42 for early infant diagnosis (EID) and 3 (1.6%) received a result by EPI-2. In Zambia, these figures were 879 of 1465 (64.0%) and 9.9% (145/1465), respectively for HIV-exposed children sampled at birth. CONCLUSION: This evaluation strategy at EPI-2 visit could strengthen program monitoring and help identifying gaps to be addressed on the last mile towards elimination of MTCT of HIV.
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Fármacos Anti-VIH , Infecciones por VIH , Lactante , Recién Nacido , Humanos , Embarazo , Femenino , Fármacos Anti-VIH/uso terapéutico , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Burkina Faso , Zambia , Estudios Transversales , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , InmunizaciónRESUMEN
Subclinical mastitis (SCM) is an important risk factor of postnatal HIV-1 transmission that is still poorly understood. A longitudinal sub-study of the ANRS12174 trial including 270 breastfeeding mothers in Lusaka, Zambia measured sodium (Na+) and potassium (K+) in archived paired breast milk samples collected at week 14, 26 and 38 postpartum to determine cumulative incidence of SCM and the effects of recurrent severe SCM on HIV-1 shedding in breast milk. A nested retrospective cohort study including 112 mothers was also done to determine longitudinal effects of SCM on four pro-inflammatory cytokines; IL6, IL8, IP10 and RANTES. The cumulative incidence for any SCM (Na + /K + ratio > 0.6) and severe SCM (Na + /K + ratio > 1) were 58.6% (95%CI: 52.7 - 64.5) and 27.8% (95%CI: 22.5 - 33.1), respectively. In majority of affected mothers (51.4%) severe SCM was recurrent. Both breasts were involved in 11.1%, 33.3% and 70% of the mothers with a single episode, 2 and 3 episodes respectively. In affected breasts, an episode of severe SCM resulted in steep upregulation of the four cytokines considered (IL8, IP10, RANTES and IL6) compared to: before and after the episode; contralateral unaffected breasts; and SCM negative control mothers. Recurrent severe SCM significantly increased the odds of shedding cell-free HIV-1 in breast milk (OR: 5.2; 95%CI: 1.7 - 15.6) whereas single episode of severe SCM did not (OR: 1.8; 95%CI: 0.8 - 4.2). A Na+/K+ ratio > 1 indicative of severe SCM is an excellent indicator of breast inflammation characterized by a steep, localized and temporal upregulation of several pro-inflammatory cytokines that favor HIV-1 shedding in mature breast milk and may facilitate postnatal HIV-1 transmission through breastfeeding.
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Infecciones por VIH , VIH-1 , Mastitis , Lactancia Materna , Quimiocina CCL5 , Quimiocina CXCL10 , Citocinas , Femenino , Infecciones por VIH/epidemiología , Humanos , Interleucina-6 , Interleucina-8 , Mastitis/epidemiología , Estudios Retrospectivos , Sodio , ZambiaRESUMEN
Post-natal HIV infection through breastfeeding remains a challenge in many low and middle-income countries, particularly due to non-availability of alternative infant feeding options and the suboptimal Prevention of Mother to Child Transmission of HIV-1 (PMTCT) cascade implementation and monitoring. The PROMISE-EPI study aims to address the latter by identifying HIV infected mothers during an almost never-missed visit for their infant, the second extended program on immunization visit at 6-8 weeks of age (EPI-2). The study is divided into 3 components inclusive of an open-label randomized controlled trial aiming to assess the efficacy of a responsive preventive intervention compared to routine intervention based on the national PMTCT guidelines for HIV-1 uninfected exposed breastfeeding infants. The preventive intervention includes: a) Point of care testing for early infant HIV diagnosis and maternal viral load; b) infant, single-drug Pre-Exposure Prophylaxis (PrEP) (lamivudine) if mothers are virally unsuppressed. The primary outcome is HIV-transmission rate from EPI-2 to 12 months. The study targets to screen 37,000 mother/infant pairs in Zambia and Burkina Faso to identify 2000 mother/infant pairs for the clinical trial. The study design and challenges faced during study implementation are described, including the COVID-19 pandemic and the amended HIV guidelines in Zambia in 2020 (triple-drug PrEP in HIV exposed infants guided by quarterly maternal viral load). The changes in the Zambian guidelines raised several questions including the equipoise of PrEP options, the standard of care-triple-drug (control arm in Zambia) versus the study-single-drug (intervention arm). Trial registration number (www.clinicaltrials.gov): NCT03869944. Submission category: Study Design, Statistical Design, Study Protocols.
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Fármacos Anti-VIH/uso terapéutico , Lactancia Materna , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/transmisión , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Lamivudine/uso terapéutico , Adolescente , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/efectos adversos , Burkina Faso , COVID-19/epidemiología , Estudios Transversales , Femenino , Infecciones por VIH/diagnóstico , Humanos , Lactante , Lamivudine/administración & dosificación , Lamivudine/efectos adversos , Pandemias , Profilaxis Pre-Exposición/métodos , Proyectos de Investigación , SARS-CoV-2 , Carga Viral , Adulto Joven , ZambiaRESUMEN
Human milk is a significant source of different CD133+ and/or CD34+ stem/progenitor-like cell subsets in healthy women but their cell distribution and percentages in this compartment of HIV-positive women have not been explored. To date, a decrease of CD34+ hematopoietic stem and progenitor cell frequencies in peripheral blood and bone marrow of HIV-positive patients has been reported. Herein, human milk and peripheral blood samples were collected between day 2-15 post-partum from HIV-positive and HIV-negative women, and cells were stained with stem cell markers and analyzed by flow cytometry. We report that the median percentage of CD45+/highCD34-CD133+ cell subset from milk and blood was significantly higher in HIV-positive than in HIV-negative women. The percentage of CD45dimCD34-CD133+ cell subset from blood was significantly higher in HIV-positive than HIV-negative women. Moreover, percentages of CD45dimCD34+, CD45dimCD34+CD133-, and CD45+highCD34+CD133- cell subsets from blood were significantly lower in HIV-positive than HIV-negative women. The CD133+ stem/progenitor-like cell subsets are increased in early human milk and blood of HIV-positive women and are differentially distributed to CD34+ cell subset frequencies which are decreased in blood.
Asunto(s)
Infecciones por VIH , Leche Humana , Antígeno AC133 , Femenino , Sangre Fetal , Citometría de Flujo , HumanosRESUMEN
BACKGROUND: Stem/progenitor cells have been identified in human milk. However, characterization and percentages of cell subsets in human milk using hematopoietic stem and progenitor cell markers according to the differential expression of CD45, i.e., as CD45dim/+ (mainly hematopoietic stem/progenitor cells) and CD45- (mainly non-hematopoietic stem/progenitor cells), have not been assessed to date. RESEARCH AIM: To characterize stem/progenitor-like cell phenotypes in human milk and to report the percentages of these cells at two different lactation stages compared to peripheral blood. METHODS: Human milk samples paired with peripheral blood samples (N = 10) were analyzed by flow cytometry using CD45, CD34, CD133, CD38, and lineage-negative markers. The percentage of cell subsets was analyzed in colostrum (Day 3 postpartum) and transitional milk (Day 5/6 postpartum) and compared with the peripheral blood counterpart. RESULTS: The percentage of CD45-CD34+ cells was predominant in both colostrum and transitional milk. The percentage of CD45+/highCD133+ cells was high in colostrum while the percentage of CD45-CD133+ cells was high in transitional milk. Furthermore, the median percentages of the CD45-CD34+, CD45-CD133+, and CD45dimCD133+ cell subsets were higher in colostrum than its peripheral blood counterpart (0.11% vs. 0.002%; 0.17% vs. 0.0005%; 0.09% vs. 0.05%, p = .04, respectively); also CD45-CD34-CD133+ and CD45dimCD34-CD133+ cell subsets were higher in colostrum than peripheral blood (1.32% vs. 0.0% and 2.4% vs. 0.06%, p = .04), respectively). CONCLUSION: Early human milk is an abundant reservoir of hematopoietic stem/progenitor-like cells in the CD45+/high population and non-hematopoietic stem/progenitor-like cells in the CD45- population.
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Antígenos Comunes de Leucocito/análisis , Leche Humana , Células Madre/metabolismo , Humanos , Antígenos Comunes de Leucocito/genética , Células Madre/citologíaRESUMEN
The risk of postnatal HIV transmission exists throughout the breastfeeding period. HIV shedding in breast milk beyond six months has not been studied extensively. The aim of this study was to determine prevalence and determinants of HIV shedding in breast milk during continued breastfeedingA cross-sectional study was nested in the PROMISE-PEP trial in Lusaka, Zambia to analyze breast milk samples collected from both breasts at week 38 post-partum (mid-way during continued breastfeeding). We measured concurrent HIV deoxyribonucleic acid (DNA) and HIV ribonucleic acid (RNA) as proxies for cell-associated HIV (CAV) and cell-free HIV (CFV) shedding in breast milk respectively. Participants' socio-demographic date, concurrent blood test results, sub clinical mastitis test results and contraceptive use data were available. Logistic regression models were used to identify determinants of HIV shedding in breast milk (detecting either CAV or CFV).The prevalence of HIV shedding in breast milk at 9 months post-partum was 79.4% (95%CI: 74.0 - 84.0). CAV only, CFV only and both CAV and CFV were detectable in 13.7%, 17.3% and 48.4% mothers, respectively. The odds of shedding HIV in breast milk decreased significantly with current use of combined oral contraceptives (AOR: 0.37; 95%CI: 0.17 - 0.83) and increased significantly with low CD4 count (AOR: 3.47; 95%CI: 1.23 - 9.80), unsuppressed plasma viral load (AOR: 6.27; 95%CI: 2.47 - 15.96) and severe sub-clinical mastitis (AOR: 12.56; 95%CI: 2.48 - 63.58).This study estimated that about 80% of HIV infected mothers not on ART shed HIV in breast milk during continued breastfeeding. Major factors driving this shedding were low CD4 count, unsuppressed plasma viral load and severe sub-clinical mastitis. The inverse relationship between breast milk HIV and use of combined oral contraceptives needs further clarification. Continued shedding of CAV may contribute to residual postnatal transmission of HIV in mothers on successful ART.
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Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Leche Humana/virología , Adulto , Antirretrovirales , Lactancia Materna , Recuento de Linfocito CD4 , Ácidos Nucleicos Libres de Células , Anticonceptivos Orales Combinados/administración & dosificación , Estudios Transversales , ADN Viral , Femenino , Humanos , Transmisión Vertical de Enfermedad Infecciosa , Modelos Logísticos , Mastitis/epidemiología , Madres , Prevalencia , ARN Viral , Factores Socioeconómicos , Carga Viral , Esparcimiento de Virus/fisiología , Adulto Joven , ZambiaRESUMEN
BACKGROUND: We characterized the extent of antiretroviral therapy (ART) experience and postdischarge mortality among hospitalized HIV-infected adults in Zambia. METHODS: At a central hospital with an opt-out HIV testing program, we enrolled HIV-infected adults (18+ years) admitted to internal medicine using a population-based sampling frame. Critically ill patients were excluded. Participants underwent a questionnaire regarding their HIV care history and CD4 count and viral load (VL) testing. We followed participants to 3 months after discharge. We analyzed prior awareness of HIV-positive status, antiretroviral therapy (ART) use, and VL suppression (VS; <1000 copies/mL). Using Cox proportional hazards regression, we assessed risk factors for mortality. RESULTS: Among 1283 adults, HIV status was available for 1132 (88.2%), and 762 (67.3%) were HIV-positive. In the 239 who enrolled, the median age was 36 years, 59.7% were women, and the median CD4 count was 183 cells/mm3. Active tuberculosis or Cryptococcus coinfection was diagnosed in 82 (34.3%); 93.3% reported prior awareness of HIV status, and 86.2% had ever started ART. In the 64.0% with >6 months on ART, 74.4% had VS. The majority (92.5%) were discharged, and by 3 months, 48 (21.7%) had died. Risk of postdischarge mortality increased with decreasing CD4, and there was a trend toward reduced risk in those treated for active tuberculosis. CONCLUSIONS: Most HIV-related hospitalizations and deaths may now occur among ART-experienced vs -naïve individuals in Zambia. Development and evaluation of inpatient interventions are needed to mitigate the high risk of death in the postdischarge period.
RESUMEN
BACKGROUND: Human breast milk cells remain poorly characterized for the presence of unconventional T lymphocytes and innate lymphoid cells (ILCs). METHODS: Early breast milk was collected from eight HIV-uninfected and 11 HIV-infected women 3-12 days after delivery. Mucosal-associated invariant T cells (MAIT cells), TCR γδ cells, and innate lymphoid cells (ILCs) were analyzed in breast milk and paired blood samples. RESULTS: CD161+/TRAV1-2 + MAIT cells were detected in breast milk, accounting for a median (IQR) of 0.08% (0.06-0.16) and 0.17% (0.16-0.31) of CD45+ breast milk cells in HIV-uninfected and HIV-infected women, respectively. A selective compartmentalization of γδ T lymphocytes was observed in breast milk. Median (IQR) frequency of γδ T lymphocytes was 8.95% (8.64-12.14) among breast milk lymphocyte cells compared to 2.54% (1.81-4.10) in blood (P = 0.03) in HIV-uninfected women, and 7.26% (4.22-10.54) in breast milk versus 3.31% (2.54-3.80) in blood (P = 0.004) from HIV-infected women. The proportion of group 1 ILC (ILC1) among total ILCs was higher in breast milk compared to blood in HIV-uninfected women (P = 0.03) and HIV-infected women (P = 0.001). The frequency of ILC2 among total ILCs tends to be lower in breast milk compared to blood in HIV-uninfected women (P = 0.06) and HIV-infected women (P = 0.03). CONCLUSION: Unconventional T cells and ILCs that may be involved in both the protection against infection of the lactating mammary gland and maturation of infant's gut and microbiomes account for a detectable fraction of breast milk cells.
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Células Sanguíneas/inmunología , Infecciones por VIH/inmunología , VIH-1/fisiología , Linfocitos/inmunología , Leche Humana/inmunología , Células T Invariantes Asociadas a Mucosa/inmunología , Separación Celular , Femenino , Citometría de Flujo , Humanos , Inmunidad Innata , Inmunofenotipificación , Lactancia , Recuento de Linfocitos , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismoRESUMEN
BACKGROUND: Little is known about human papillomavirus (HPV) shedding in human breast milk. OBJECTIVE: To investigate HPV shedding in mature breast milk specimens collected from breastfeeding African women living with HIV-1 and not receiving antiretroviral treatment. DESIGN: 62 African women enrolled in the ANRS 12174 trial participated in this study. 79 lactoserum specimens obtained from right and/or left breasts from 42 Zambian women as well as lactosera and cell pellets from 40 milk samples collected from right and left breasts among 20 Ugandan women were tested for HPV using the INNO-LiPA HPV Genotyping Extra II assay. RESULTS: HPV DNA was detected in 9 (11.4%) lactoserum specimens collected from 8 (19.0%) Zambian women. Fourteen (17.5%) samples from 5 (25%) Ugandan women were positive for HPV detection. Differences in HPV type identification between the two breasts as well as between lactoserum and cell pellet were oberved. Overall, 13 (21.0%) of the 62 women included in this study had detectable HPV DNA in their breast milk, representing 11 HPV types, including high-risk, probable high-risk and low-risk types. CONCLUSION: This study confirms that HPV can be frequently detected in breast milk in HIV-infected women. Further studies are needed to understand the way by which maternal milk can shed HPV.
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ADN Viral/análisis , Leche Humana/virología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Esparcimiento de Virus , Adulto , África/epidemiología , Lactancia Materna , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , VIH-1 , Humanos , Papillomaviridae/clasificación , Papillomaviridae/genética , Uganda/epidemiología , Zambia/epidemiologíaRESUMEN
Epstein-Barr virus (EBV) in breast milk and subclinical mastitis (SCM) are both associated with human immunodeficiency virus (HIV) shedding and possibly with postnatal HIV transmission. The objective of this nested case-control study was to investigate the interplay between SCM and EBV replication in breast milk of HIV-infected mothers.The relationships between EBV deoxyribonucleic acid (DNA) shedding, HIV-1 ribonucleic acid (RNA) level, and SCM were explored in breast milk samples of Zambian mothers participating in the ANRS 12174 trial. Mammary gland inflammation was defined as a breast milk sodium to potassium ratio (Na/K) greater than 0.6 and further subclassified as either "possible SCM" (Na/K ratio 0.6-1.0) or SCM (Na/K ratioâ≥â1.0). Breast milk interleukin 8 (IL-8) was measured as a surrogate marker of mammary gland inflammation.EBV DNA was detected in breast milk samples from 42 out of 83 (51%) participants and was associated with HIV-1 shedding in breast milk (P = 0.006). EBV DNA levels were higher in samples with SCM and "possible SCM" compared to non-SCM breast milk samples (P = 0.06; P = 0.007). An EBV DNA level of >200âcopies/mL was independently associated with SCM and "possible SCM" (OR: 2.62; 95%: 1.13-6.10). In patients with SCM, higher EBV replication in the mammary gland was associated with a lower induction of IL-8 (P = 0.013). Resistance to DNase treatment suggests that EBV DNA in lactoserum is encapsidated.SCM and decreased IL-8 responses are associated with an increased EBV shedding in breast milk which may in turn facilitate HIV replication in the mammary gland.
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Infecciones por VIH/transmisión , VIH-1/fisiología , Herpesvirus Humano 4/fisiología , Transmisión Vertical de Enfermedad Infecciosa , Mastitis/virología , Leche Humana/virología , Esparcimiento de Virus , Adulto , Recuento de Linfocito CD4 , ADN Viral/análisis , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Recién Nacido , ARN Viral/análisis , ZambiaRESUMEN
BACKGROUND: Strategies to prevent postnatal mother-to-child transmission of HIV-1 in Africa, including infant prophylaxis, have never been assessed past 6 months of breastfeeding, despite breastfeeding being recommended up to 12 months after birth. We aimed to compare the efficacy and safety of infant prophylaxis with the two drug regimens (lamivudine or lopinavir-ritonavir) to prevent postnatal HIV-1 transmission up to 50 weeks of breastfeeding. METHODS: We did a randomised controlled trial in four sites in Burkina Faso, South Africa, Uganda, and Zambia in children born to HIV-1-infected mothers not eligible for antiretroviral therapy (CD4 count >350 cells per µL). An independent researcher electronically generated a randomisation schedule; we then used sequentially numbered envelopes to randomly assign (1:1) HIV-1-uninfected breastfed infants aged 7 days to either lopinavir-ritonavir or lamivudine (paediatric liquid formulations, twice a day) up to 1 week after complete cessation of breastfeeding or at the final visit at week 50. We stratified the randomisation by country and used permuted blocks of four and six. We used a study label on drug bottles to mask participants, study physicians, and assessors to the treatment allocation. The primary outcome was infant HIV-1 infection between age 7 days and 50 weeks, diagnosed every 3 months with HIV-1 DNA PCR, in the modified intention-to-treat population (all who attended at least one follow-up visit). This trial is registered with ClinicalTrials.gov, number NCT00640263. FINDINGS: Between Nov 16, 2009, and May 7, 2012, we enrolled and randomised 1273 infants and analysed 1236; 615 assigned to lopinavir-ritonavir or 621 assigned to lamivudine. 17 HIV-1 infections were diagnosed in the study period (eight in the lopinavir-ritonavir group and nine in the lamivudine group), resulting in cumulative HIV-1 infection of 1.4% (95% CI 0.4-2.5) and 1.5% (0.7-2.5), respectively. Infection rates did not differ between the two drug regimens (hazard ratio [HR] of lopinavir-ritonavir versus lamivudine of 0.90, 95% CI 0.35-2.34; p=0.83). Clinical and biological severe adverse events did not differ between groups; 251 (51%) infants had a grade 3-4 event in the lopinavir-ritonavir group compared with 246 (50%) in the lamivudine group. INTERPRETATION: Infant HIV-1 prophylaxis with lopinavir-ritonavir was not superior to lamivudine and both drugs led to very low rates of HIV-1 postnatal transmission for up to 50 weeks of breastfeeding. Infant pre-exposure prophylaxis should be extended until the end of HIV-1 exposure and mothers should be informed about the persistent risk of transmission throughout breastfeeding. FUNDING: INSERM/National Agency for Research on AIDS and Viral Hepatitis (including funds from the Total Foundation), European Developing Countries Clinical Trials Partnership, Research Council of Norway.