Karin Nielsen-Saines

Prevention of HIV-1 Infection with Early Antiretroviral Therapy

BACKGROUND Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. METHODS In nine countries, we enrolled 1763 couples in which one partner was HIV-1-positive and the other was HIV-1-negative; 54% of the subjects were from Africa, and 50% of infected partners were men. HIV-1-infected subjects with CD4 counts between 350 and 550 cells per cubic millimeter were randomly assigned in a 1:1 ratio to receive antiretroviral therapy either immediately (early therapy) or after a decline in the CD4 count or the onset of HIV-1-related symptoms (delayed therapy). The primary prevention end point was linked HIV-1 transmission in HIV-1-negative partners. The primary clinical end point was the earliest occurrence of pulmonary tuberculosis, severe bacterial infection, a World Health Organization stage 4 event, or death. RESULTS As of February 21, 2011, a total of 39 HIV-1 transmissions were observed (incidence rate, 1.2 per 100 person-years; 95% confidence interval [CI], 0.9 to 1.7); of these, 28 were virologically linked to the infected partner (incidence rate, 0.9 per 100 person-years, 95% CI, 0.6 to 1.3). Of the 28 linked transmissions, only 1 occurred in the early-therapy group (hazard ratio, 0.04; 95% CI, 0.01 to 0.27; P<0.001). Subjects receiving early therapy had fewer treatment end points (hazard ratio, 0.59; 95% CI, 0.40 to 0.88; P=0.01). CONCLUSIONS The early initiation of antiretroviral therapy reduced rates of sexual transmission of HIV-1 and clinical events, indicating both personal and public health benefits from such therapy. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 052 ClinicalTrials.gov number, NCT00074581.).

Antiretroviral therapy for the prevention of HIV-1 transmission

BACKGROUND An interim analysis of data from the HIV Prevention Trials Network (HPTN) 052 trial showed that antiretroviral therapy (ART) prevented more than 96% of genetically linked infections caused by human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. ART was then offered to all patients with HIV-1 infection (index participants). The study included more than 5 years of follow-up to assess the durability of such therapy for the prevention of HIV-1 transmission. METHODS We randomly assigned 1763 index participants to receive either early or delayed ART. In the early-ART group, 886 participants started therapy at enrollment (CD4+ count, 350 to 550 cells per cubic millimeter). In the delayed-ART group, 877 participants started therapy after two consecutive CD4+ counts fell below 250 cells per cubic millimeter or if an illness indicative of the acquired immunodeficiency syndrome (i.e., an AIDS-defining illness) developed. The primary study end point was the diagnosis of genetically linked HIV-1 infection in the previously HIV-1-negative partner in an intention-to-treat analysis. RESULTS Index participants were followed for 10,031 person-years; partners were followed for 8509 person-years. Among partners, 78 HIV-1 infections were observed during the trial (annual incidence, 0.9%; 95% confidence interval [CI], 0.7 to 1.1). Viral-linkage status was determined for 72 (92%) of the partner infections. Of these infections, 46 were linked (3 in the early-ART group and 43 in the delayed-ART group; incidence, 0.5%; 95% CI, 0.4 to 0.7) and 26 were unlinked (14 in the early-ART group and 12 in the delayed-ART group; incidence, 0.3%; 95% CI, 0.2 to 0.4). Early ART was associated with a 93% lower risk of linked partner infection than was delayed ART (hazard ratio, 0.07; 95% CI, 0.02 to 0.22). No linked infections were observed when HIV-1 infection was stably suppressed by ART in the index participant. CONCLUSIONS The early initiation of ART led to a sustained decrease in genetically linked HIV-1 infections in sexual partners. (Funded by the National Institute of Allergy and Infectious Diseases; HPTN 052 ClinicalTrials.gov number, NCT00074581 .).

Effects of early versus delayed initiation of antiretroviral treatment on clinical outcomes of HIV-1 infection: results from the phase 3 HPTN 052 randomised controlled trial

BACKGROUND Use of antiretroviral treatment for HIV-1 infection has decreased AIDS-related morbidity and mortality and prevents sexual transmission of HIV-1. However, the best time to initiate antiretroviral treatment to reduce progression of HIV-1 infection or non-AIDS clinical events is unknown. We reported previously that early antiretroviral treatment reduced HIV-1 transmission by 96%. We aimed to compare the effects of early and delayed initiation of antiretroviral treatment on clinical outcomes. METHODS The HPTN 052 trial is a randomised controlled trial done at 13 sites in nine countries. We enrolled HIV-1-serodiscordant couples to the study and randomly allocated them to either early or delayed antiretroviral treatment by use of permuted block randomisation, stratified by site. Random assignment was unblinded. The HIV-1-infected member of every couple initiated antiretroviral treatment either on entry into the study (early treatment group) or after a decline in CD4 count or with onset of an AIDS-related illness (delayed treatment group). Primary events were AIDS clinical events (WHO stage 4 HIV-1 disease, tuberculosis, and severe bacterial infections) and the following serious medical conditions unrelated to AIDS: serious cardiovascular or vascular disease, serious liver disease, end-stage renal disease, new-onset diabetes mellitus, and non-AIDS malignant disease. Analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00074581. FINDINGS 1763 people with HIV-1 infection and a serodiscordant partner were enrolled in the study; 886 were assigned early antiretroviral treatment and 877 to the delayed treatment group (two individuals were excluded from this group after randomisation). Median CD4 counts at randomisation were 442 (IQR 373-522) cells per μL in patients assigned to the early treatment group and 428 (357-522) cells per μL in those allocated delayed antiretroviral treatment. In the delayed group, antiretroviral treatment was initiated at a median CD4 count of 230 (IQR 197-249) cells per μL. Primary clinical events were reported in 57 individuals assigned to early treatment initiation versus 77 people allocated to delayed antiretroviral treatment (hazard ratio 0·73, 95% CI 0·52-1·03; p=0·074). New-onset AIDS events were recorded in 40 participants assigned to early antiretroviral treatment versus 61 allocated delayed initiation (0·64, 0·43-0·96; p=0·031), tuberculosis developed in 17 versus 34 patients, respectively (0·49, 0·28-0·89, p=0·018), and primary non-AIDS events were rare (12 in the early group vs nine with delayed treatment). In total, 498 primary and secondary outcomes occurred in the early treatment group (incidence 24·9 per 100 person-years, 95% CI 22·5-27·5) versus 585 in the delayed treatment group (29·2 per 100 person-years, 26·5-32·1; p=0·025). 26 people died, 11 who were allocated to early antiretroviral treatment and 15 who were assigned to the delayed treatment group. INTERPRETATION Early initiation of antiretroviral treatment delayed the time to AIDS events and decreased the incidence of primary and secondary outcomes. The clinical benefits recorded, combined with the striking reduction in HIV-1 transmission risk previously reported, provides strong support for earlier initiation of antiretroviral treatment. FUNDING US National Institute of Allergy and Infectious Diseases.

From Mosquitos to Humans: Genetic Evolution of Zika Virus

Initially isolated in 1947, Zika virus (ZIKV) has recently emerged as a significant public health concern. Sequence analysis of all 41 known ZIKV RNA open reading frames to date indicates that ZIKV has undergone significant changes in both protein and nucleotide sequences during the past half century.

Excessive Early Mortality in the First Year of Treatment in HIV Type 1-Infected Patients Initiating Antiretroviral Therapy in Resource-Limited Settings

The response to treatment and risk factors for early mortality following initiation of combination antiretrovirals(ARVs) in a cohort of African patients are described in a retrospective cohort design. Medical history, laboratory parameters, and mortality data were reviewed for patients initiating ARVs in 12 clinical centers in Mozambique, Tanzania, and Malawi. Among 3456 HIV-1-infected patients who received ARVs for more than 6 months, at baseline 72% had WHO clinical stages 3/4, 7% had a viral load 400 copies/ml, and 38% had a CD4 cell count >200/microl. One year later, 78% had undetectable virus loads and 79% had CD4 cell counts >200 cells/mm3. In the first year of HAART 260 deaths occurred (97 per 1000 person/years) with mortality peaking in the first 3 months. The highest mortality was observed in patients with low BMI, low hemoglobin levels, and CD4 values <200 cells/microl at baseline. Mortality rates following initiation of HAART are higher in patients in resource-limited areas, particularly in the first 90 days following treatment initiation.HAART initiated at higher CD4 cell count levels, especially among malnourished and/or anemic patients, will carry significant public health impact.

Increased infant human immunodeficiency virus-type one free survival at one year of age in Sub-Saharan Africa with maternal use of highly active antiretroviral therapy during breast-feeding.

Background: Reduction of HIV-1 breast-feeding transmission remains a challenge for prevention of pediatric infections in Sub-Saharan Africa. Provision of formula decreases transmission but often increases child mortality in this setting. Methods: A prospective observational cohort study of HIV-1 exposed infants of mothers receiving pre and postnatal medical care at Drug Resource Enhancement Against AIDS and Malnutrition centers in Mozambique was conducted. Live-born infants of HIV-1-infected women receiving medical care were enrolled. HIV-1 testing was performed at 1, 6, and 12 months of age using branched DNA. Mothers were counseled to breast-feed exclusively for 6 months and were provided HAART antenatally and postnatally for the first 6 months. Women with CD4 cell counts less than 350/cmm at baseline continued HAART indefinitely. Results: Of 341 infants followed from birth, 313 mother-infant pairs (92%) completed 6 months and 283 (83%) completed 12 months of follow-up. HIV-1 diagnosis was ascertained in 287 infants (84%) including 4 who died. There were 8 cases of HIV-1 transmission: 4 of 341 (1.2%) at 1 month, 2 of 313 (0.6%) at 6 months, and 2 of 276 (0.7%) at 12 months (cumulative rate: 2.8%). Two mothers (0.6%) and 11 infants (3.2%) died. Maternal and infant mortality rates were 587 of 100,000 and 33 of 1000, while country rates are 1000 of 100,000 and 101 of 1000. HIV risk reduction was 93% and HIV-free survival at 12 months was 94%. Conclusions: Late postnatal transmission of HIV-1 is significantly decreased by maternal use of HAART with high infant survival rates up to 12 months of age.

Extended antenatal use of triple antiretroviral therapy for prevention of mother-to-child transmission of HIV-1 correlates with favorable pregnancy outcomes

Objective:To evaluate pregnancy outcomes in a cohort of HIV-infected women receiving triple antiretroviral therapy (ART) for prevention of mother-to-child-transmission. Methods:A retrospective cohort study with review of records of 3273 HIV-positive women receiving prenatal care in Malawi and Mozambique from July 2005 to December 2009 was conducted in Drug Resource Enhancement Against AIDS and Malnutrition (DREAM) centers. Patients were offered nevirapine-based triple ART initiated in pregnancy until 6 months postpartum. Main outcome measures were maternal mortality, abortion/stillbirth, prematurity, and low birth weight. Results:Maternal mortality was 1.2% (42/3273): 7.4% in 68 women with no antenatal ART and 0.7% in 1370 with at least 90 days of antenatal ART [P < 0.001; odds ratio (OR) 0.29 (95% confidence interval [CI] 0.14–0.96]. Abortion/stillbirth was 5.2% (169/3273): 26.5% in 68 women with no ART and 5.0% in 1370 women with at least 90 days of antenatal ART [P < 0.001; OR 0.39 (95% CI 0.27–0.57)]. Prematurity was 19.1%: 70% in 10 women with no antenatal ART and 8.5% in 1330 women with at least 90 days of antenatal ART [P < 0.001; OR 0.15 (95% CI 0.14–0.19)]. Low birth weight was 11.5% (57/496) and not associated with ART duration. The protective effect of antenatal ART against mortality, fetal demise, and prematurity was independent of CD4 strata. Multivariate analysis for BMI, CD4 cell count, virus load, days in care, predelivery length of ART, and hemoglobin demonstrated an independent association between predelivery length of ART and CD4 with maternal mortality, abortion/stillbirth, and prematurity. ART toxicities were infrequent (5.2%). Conclusion:Antenatal triple ART reduces adverse pregnancy outcomes in HIV-infected women.

Sexual transmission of HIV-1 among serodiscordant couples in Porto Alegre, southern Brazil.

Background: A cohort of 93 heterosexual HIV serodiscordant couples with no prior antiretroviral use were identified in a large referral center from February 2000 to January 2006 in southern Brazil. Methods: Review of clinic records retrospectively identified 56 cases of untreated index cases whereas 37 couples were identified prospectively. Demographics, medical, and laboratory data were obtained. During follow-up, 41/93 index cases (44%) initiated antiretrovirals (ARVs) and from 52 without ARV use, 4 were lost to follow-up. Median viral loads were used to compare transmitters versus nontransmitters (Mann-Whitney test). Results: Sixty-seven (72%) index cases were female (49% identified during ante-natal care). Unprotected sexual intercourse as a risk factor for HIV-1 infection was significantly higher as compared to intravenous drug use (P < 0.0001) in female index partners but not in male index cases. Sexually transmitted diseases were identified in 22 cases (24%). Six HIV-1 seroconversions occurred (6.5%). In all cases index partners were not using ARVs at the time of seroconversion. Among 26 couples with a male index case, there were 4 seroconversions (15%) and among 67 female index cases there were 2 seroconversions (3%). All seroconversions occurred with virus loads >1000 copies/mL. Eight female index cases (22%) reported no condom use. Conclusions: Heterosexual transmission occurred more frequently from HIV-infected males to females (rate ratio 3.5; CI, 95% 0.8–16.5 P = 0.259), although without statistical significance, probably because of the small sample. Transmitters showed significantly higher median viral loads (P = 0.042) suggesting that heterosexual transmission of HIV is more a function of viral load than gender of index case. ARV use may play a role in the prevention of HIV-1 heterosexual transmission. Other factors may be involved and should be further evaluated in larger cohorts.

Pharmacokinetics and Safety of Tenofovir in HIV-Infected Women During Labor and Their Infants During the First Week of Life

Background:Data describing the pharmacokinetics and safety of tenofovir in neonates are lacking. Methods:The HIV Prevention Trials Network 057 protocol was a phase 1, open-label study of the pharmacokinetics and safety of tenofovir disoproxil fumarate (TDF) in HIV-infected women during labor and their infants during the first week of life with 4 dosing cohorts: maternal 600 mg doses/no infant dosing; no maternal dosing/infant 4 mg/kg doses on days 0, 3, and 5; maternal 900 mg doses/infant 6 mg/kg doses on days 0, 3, and 5; maternal 600 mg doses/infant 6 mg/kg daily for 7 doses. Pharmacokinetic sampling was performed on cohort 1 and 3 mothers and all infants. Plasma, amniotic fluid, and breast milk tenofovir concentrations were determined by liquid chromatographic–tandem mass spectrometric assay. The pharmacokinetic target was for infant tenofovir concentration throughout the first week of life to exceed 50 ng/mL, the median trough tenofovir concentration in adults receiving standard chronic TDF dosing. Results:One hundred twenty-two mother–infant pairs from Malawi and Brazil were studied. Tenofovir exposure in mothers receiving 600 and 900 mg exceeded that in nonpregnant adults receiving standard 300 mg doses. Tenofovir elimination in the infants was equivalent to that in older children and adults, and trough tenofovir plasma concentrations exceeded 50 ng/mL in 74%–97% of infants receiving daily dosing. Conclusions:A TDF dosing regimen of 600 mg during labor and daily infant doses of 6 mg/kg maintains infant tenofovir plasma concentration above 50 ng/mL throughout the first week of life and should be used in the studies of TDF efficacy for HIV prevention of mother-to-child transmission and early infant treatment.

Regional brain gray and white matter changes in perinatally HIV-infected adolescents

Despite the success of antiretroviral therapy (ART), perinatally infected HIV remains a major health problem worldwide. Although advance neuroimaging studies have investigated structural brain changes in HIV-infected adults, regional gray matter (GM) and white matter (WM) volume changes have not been reported in perinatally HIV-infected adolescents and young adults. In this cross-sectional study, we investigated regional GM and WM changes in 16 HIV-infected youths receiving ART (age 17.0 ± 2.9 years) compared with age-matched 14 healthy controls (age 16.3 ± 2.3 years) using magnetic resonance imaging (MRI)-based high-resolution T1-weighted images with voxel based morphometry (VBM) analyses. White matter atrophy appeared in perinatally HIV-infected youths in brain areas including the bilateral posterior corpus callosum (CC), bilateral external capsule, bilateral ventral temporal WM, mid cerebral peduncles, and basal pons over controls. Gray matter volume increase was observed in HIV-infected youths for several regions including the left superior frontal gyrus, inferior occipital gyrus, gyrus rectus, right mid cingulum, parahippocampal gyrus, bilateral inferior temporal gyrus, and middle temporal gyrus compared with controls. Global WM and GM volumes did not differ significantly between groups. These results indicate WM injury in perinatally HIV-infected youths, but the interpretation of the GM results, which appeared as increased regional volumes, is not clear. Further longitudinal studies are needed to clarify if our results represent active ongoing brain infection or toxicity from HIV treatment resulting in neuronal cell swelling and regional increased GM volume. Our findings suggest that assessment of regional GM and WM volume changes, based on VBM procedures, may be an additional measure to assess brain integrity in HIV-infected youths and to evaluate success of current ART therapy for efficacy in the brain.