Effectiveness of antiretroviral therapy initiated before the age of 2 months in infants vertically infected with human immunodeficiency virus type 1

The HIV-1 antibody response: a footprint of the viral reservoir in children vertically infected with HIV

Several assays have been developed to measure and characterise the replication-competent HIV-1 reservoir, which constitutes the barrier to cure. To date, the application of these assays to studies in children and in limited-resource settings has been minimal, primarily because of their expense, the large required blood volumes, and labour-intensive technologies. For children vertically infected with HIV-1 who initiated suppressive antiretroviral therapy (ART) regimens in infancy, HIV-1-specific antibody concentrations are associated with viral persistence and could be used to estimate the size of the residual latent reservoir on ART. This strategy could be particularly useful for screening children on suppressive ART for enrolment into therapeutic vaccine trials and other protocols aimed at achieving HIV-1 remission.

Reactivity of Routine HIV Antibody Tests in Children With Perinatally Acquired HIV-1 in England: Cross-sectional Analysis

We assessed HIV antibody prevalence in children with perinatally acquired HIV in England. Eighteen percent (10/55) of those starting combination antiretroviral therapy <6 months of age were seronegative at median age 9.1 years and had lower viral load at diagnosis and combination antiretroviral therapy start and fewer viral rebounds, than 45 of 55 seropositives. Implications for patient selection for HIV cure research, and interpretation of routine antibody testing, are discussed.

Early antiretroviral therapy in HIV-infected infants: can it lead to HIV remission?

Interventions to prevent mother-to-child HIV transmission have been extremely successful, but new HIV infections continue to occur in infants. Strong evidence indicates that combination antiretroviral therapy (ART) for treatment should be started in HIV-infected infants to prevent early morbidity and mortality. In 2013, the report of the Mississippi baby, who was started on ART within 30 h of life and maintained off-treatment remission for 27 months before HIV was once again detectable, generated renewed interest in very early ART initiation. The case stimulated interest in the possibility of HIV remission, which we define as maintenance of plasma viraemia below the threshold of detection in the absence of ART, after early treatment initiation. The possibility of HIV remission elicits much hope, given that children with HIV infection currently face a lifetime of treatment. The potential for early ART to lead to HIV remission in infants can be thought of in terms of six factors: rapidity of viral suppression with very early ART; initial viral suppression rate with early ART; later virological control after early treatment; the effect of early treatment on the viral reservoir size; outcomes of randomised trials of structured treatment interruption; and the likelihood of viral rebound in neonates after ART cessation. Review of existing data suggests that achieving long-term remission off treatment remains elusive, and concentrated attention and commitment of the scientific community is needed to investigate the factors that might help to reach this goal.

The pharmacological treatment of acute HIV infections in neonates

INTRODUCTION

Recent goals of antiretroviral treatment of neonates have expanded from reducing morbidity and mortality to also aiming to facilitate HIV remission. Areas covered: In this review, we present and discuss the rationale and evidence-bases for each of these distinct goals. Next we discuss the challenges of how to identify HIV-infected neonates. Finally, we discuss the specific antiretroviral drugs that are preferred for this group, making distinctions between the use of these agents in prevention and treatment. Expert commentary: The clinical and scientific challenges of pharmacological treatment of acute HIV infection in neonates are complicated by externalities beyond biology. At the same time, these challenges are energized by the unique biological opportunities afforded by investigating this population, including a unique immune profile, ability to study both mother and neonate as well as transmitted and acquired virus, and time period spanning both the period soon after infection as well as the period of viral reservoir establishment and related damage. Given the unique scientific opportunities afforded by study of pharmacologic treatment of acute HIV infection in neonates, we hypothesize that over the next five years breakthroughs may occur that may lead to new interventions effective at achieving HIV remission.

Qualitative and quantitative HIV antibodies and viral reservoir size characterization in vertically infected children with virological suppression

Background

Absence of detectable viraemia after treatment cessation in some vertically HIV-infected (VHIV) children suggests that early initiation of HAART could lead to functional cure.

Objectives

We described the factors associated with HIV antibody levels and the viral reservoir size in HAART-treated VHIV children.

Methods

Study included 97 VHIV children with virological suppression, in Bamako, Mali. The anti-gp41 antibody activities and HIV serostatus were assessed. The viral reservoir size was measured by quantifying total cell-associated HIV DNA.

Results

Among the children studied, the median total HIV DNA level was 445 copies/10 6 cells (IQR = 187-914) and the median anti-gp41 antibody activity was 0.29 OD (IQR = 0.18-0.75). Low activity of anti-gp41 antibodies was associated with a younger age of HAART initiation ( P  =   0.01). Overall, eight HIV-1 seroreversions were identified.

Conclusions

Study identified potential candidates with low viral reservoir and low antibody levels or activities for future trials aiming to reduce HIV-1 reservoir to limit HAART duration.

Young age at start of antiretroviral therapy and negative HIV antibody results in HIV-infected children when suppressed

BACKGROUND

Negative results on standard HIV antibody tests have been described among HIV-infected children suppressed on antiretroviral therapy (ART) started early in life. Here, we describe the frequency and predictors of this phenomenon in a well characterized cohort of treated children.

METHODS

We selected samples from 103 HIV-infected children who started ART 14 months of age or less and from 122 children who started 6 months of age or less followed as part of two sequential clinical trials in Johannesburg, South Africa. Children had attained viral suppression on ART and had received ART for between 3 and 6.4 years (mean 4.3 years) when tested for HIV antibody using a standard ELISA (Genescreen HIV1/2 version 2; Bio-rad).

RESULTS

Only children 6 months of age or less when ART was started had negative antibody results when tested after suppression on ART several years later. Negative or low-positive antibody results were observed in 40.0, 37.0 and 27.8% of children starting ART less than 2 months of age, or starting during month 2 or 3, respectively. This dropped to 5.9, 3.5 and 5.3% if ART was started during month 4, 5 and 6, respectively. Higher CD4 percentage prior to ART initiation and no recorded intermittent viremia also predicted negative antibody results.

CONCLUSION

Testing negative on standard HIV antibody tests occurs fairly commonly among HIV-infected children who started ART 3 months of age or less and are virally suppressed. It would be prudent in clinical practice to avoid HIV antibody tests among virally suppressed, early-treated children to prevent unnecessary confusion.

HIV-1 seroreversion in HIV-1-infected children: do genetic determinants play a role?

BACKGROUND

HIV-1 seroreversion in infants with vertically transmitted HIV-1 infection who started ART in the first months of life has been reported in only a subset of patients. However, the reason why most infants remain seropositive despite similar treatment response is not understood. Here, we assessed whether HIV-1 seroreversion in maternally infected infants is associated with genetic determinants.

METHODS

HIV-1-infected infants with a history of documented HIV-1 seroreversion were identified throughout Germany using a standardized questionnaire. At study entry immune reconstitution and anti-HIV-1 antibody expression were monitored as clinical parameters. To search for genetic determinants high-resolution HLA genotyping was performed. In addition, the coding sequence of the chemokine receptor CCR5 was analyzed by Sanger sequencing regarding potential mutations.

RESULTS

Patients showed normal numbers and frequencies of lymphocyte subpopulations. Five out of eight patients still had seronegative HIV-1 antibody status at study entry. HLA genotyping revealed the enrichment of HLA-DQB1*03 and DQB1*06 alleles within the patient cohort. Only one patient was found to carry a 32 bp-deletion within the CCR5 gene.

CONCLUSION

Our results indicate that the phenotype of HIV-1 seroreversion in infants might correlate with the presence of HLA class II alleles DQB1*03 and DQB1*06. This finding supports the idea of genetic predisposition determining HIV-1 seroreversion in vertically infected infants effectively treated with ART.

False-negative post-18-month confirmatory HIV tests in HIV DNA PCR-positive children: a retrospective analysis

OBJECTIVE

The WHO guidelines for children less than 18 months old diagnosed with HIV based on presumptive clinical diagnosis or one virologic test recommend confirmatory HIV antibody testing after 18 months of age. This study describes post-18-month HIV test results following this WHO-recommended confirmatory testing strategy.

DESIGN

Case series and retrospective review of routine program data.

METHODS

Children enrolled at the Baylor Children's Clinical Center of Excellence, a pediatric and family HIV clinic in Maseru, Lesotho from December 2005 through January 2009 with a positive HIV DNA PCR at less than 18 months of age and HIV rapid test results after 18 months of age were included. Post-18-month confirmatory HIV test results are described. Factors associated with non-positive confirmatory rapid tests were determined using binary logistic regression.

RESULTS

Of the 109 children meeting inclusion criteria, 22 (20.2%) had negative and 27 (24.8%) discordant confirmatory rapid tests. Forty-six of these 49 were on antiretroviral therapy (ART). Among these 49, 11 of 24 post-18-month HIV DNA PCRs were negative, whereas nine of 10 post-18-month HIV ELISAs were positive; 29 were definitively and 17 probably HIV-infected, two were uninfected, and one had undetermined status. Only age less than 9 months at ART initiation (odds ratio 4.25, P = 0.002) was associated with non-positive rapid tests.

CONCLUSION

False-negative post-18-month confirmatory rapid tests and HIV DNA PCRs in children on ART are common, associated with early ART initiation, and may lead to inappropriate ART discontinuation and discharge from care of truly HIV-infected children.

Suboptimal immune reconstitution in vertically HIV infected children: a view on how HIV replication and timing of HAART initiation can impact on T and B-cell compartment

Today, HIV-infected children who have access to treatment face a chronic rather than a progressive and fatal disease. As a result, new challenges are emerging in the field. Recent lines of evidence outline several factors that can differently affect the ability of the immune system to fully reconstitute and to mount specific immune responses in children receiving HAART. In this paper, we review the underlying mechanisms of immune reconstitution after HAART initiation among vertically HIV-infected children analyzing the possible causes of suboptimal responses.

False negative HIV antibody test in HIV infected children who receive early antiretroviral treatment in a resource-limited setting

With the implementation of 2010 World Health Organization guidelines, the number of infants from developing countries who will initiate antiretroviral therapy (ART) will increase considerably. In this study we describe the HIV antibody tests of 14 HIV infected children who initiated ART at age less than one year in a rural setting of India. The HIV rapid test was negative in seven and indeterminate in two cases, whereas the HIV enzyme-linked immunosorbent assay (ELISA) antibody test was negative in three and indeterminate in one case. In one child who had both negative HIV rapid test and ELISA initially, HIV serology turned positive after having a virological failure to ART, suggesting the possibility of utilizing HIV serology for monitoring ART effectiveness in children who experience HIV seroreversion. In conclusion, HIV seroreversion of children with early initiation of ART is common and should be considered for avoiding misdiagnosis of HIV infection.

Short- and long-term immunological and virological outcome in HIV-infected infants according to the age at antiretroviral treatment initiation

The clinical benefit of antiretroviral therapy in infants is established. In this cohort collaboration, we compare immunological and virological response to treatment started before or after 3 months of age. Early initiation provides a better short-term response, although evolution after 12 months of age is similar in both groups.

Post-HAART outcomes in pediatric populations: comparison of resource-limited and developed countries

CONTEXT

No formal comparison has been made between the pediatric post-highly active antiretroviral therapy (HAART) outcomes of resource-limited and developed countries.

OBJECTIVE

To systematically quantify and compare major baseline characteristics and clinical end points after HAART between resource-limited and developed settings.

METHODS

Published articles and abstracts (International AIDS Society 2009, Conference on Retroviruses and Opportunistic Infections 2010) were examined from inception (first available publication for each search engine) to March 2010. Publications that contained data on post-HAART mortality, weight-for-age z score (WAZ), CD4 count, or viral load (VL) changes in pediatric populations were reviewed. Selected studies met the following criteria: (1) patients were younger than 21 years; (2) HAART was given (≥ 3 antiretroviral medications); and (3) there were >20 patients. Data were extracted for baseline age, CD4 count, VL, WAZ, and mortality, CD4 and virologic suppression over time. Studies were categorized as having been performed in a resource-limited country (RLC) or developed country (DC) on the basis of the United Nations designation. Mean percentage of deaths per cohort and deaths per 100 child-years, baseline CD4 count, VL, WAZ, and age were calculated for RLCs and DCs and compared by using independent samples t tests.

RESULTS

Forty RLC and 28 DC publications were selected (N = 17 875 RLCs; N = 1835 DC). Mean percentage of deaths per cohort and mean deaths per 100 child-years after HAART were significantly higher in RLCs than DCs (7.6 vs 1.6, P < .001, and 8.0 vs 0.9, P < .001, respectively). Mean baseline CD4% was 12% in RLCs and 23% in DCs (P = .01). Mean baseline VLs were 5.5 vs 4.7 log(10) copies per mL in RLCs versus DCs (P < .001).

CONCLUSIONS

Baseline CD4% and VL differ markedly between DCs and RLCs, as does mortality after pediatric HAART. Earlier diagnosis and treatment of pediatric HIV in RLCs would be expected to result in better HAART outcomes.

Update on antiretroviral therapy in paediatrics

This review provides an update on the most relevant issues concerning the current management of HIV infection in infants and children. Tremendous progress has been made over the last few years to diagnose and treat infants and children with HIV infection, yet much remains to be done. Every day there are nearly 1150 new infections in children under 15 years of age, more than 90% of them occurring in the developing world and most being the result of transmission from mother-to-child (WHO 2008). The comprehensive approach to preventing mother-to-child transmission (MTCT) has clearly reduced the number of children acquiring the infection in Western countries; while a further reduction of mother-to-child transmission should be aimed for personalized setting, specific intervention needs to be put in place and new efforts are now required in order to optimise treatment and care in HIV-infected children. The prompt initiation of treatment and a careful selection of first-line regimen, which considers potency as well as tolerability remain central. In addition, occurrence and prevention of opportunistic infections, adherence as well as long-term psychosocial consequences are becoming more and more relevant in the era of effective antiretroviral therapy. This article forms part of a special issue of Antiviral Research marking the 25th anniversary of Antiretroviral Drug Discovery and Development, vol. 85, issue 1, 2010.

Effect of early antiretroviral therapy on the risk of AIDS/death in HIV-infected infants

OBJECTIVE

In the absence of treatment, rapid progression to AIDS occurs in approximately 20% of HIV-1-infected infants over the first year of life. The prognosis of these children has considerably improved with highly active antiretroviral therapy. As data from well resourced countries are lacking, the objective of this collaborative study was to evaluate the impact of early treatment in vertically infected infants.

DESIGN

Children born to HIV-infected mothers between 1 September 1996 and 31 December 2004, who were diagnosed with HIV and free of AIDS before 3 months, were eligible. Demographics and pregnancy data, details of antiretroviral therapy, and clinical outcome were collected from 11 European countries.

METHODS

The risk of AIDS or death, by whether or not an infant started treatment before 3 months of age, was estimated by Kaplan-Meier survival analysis and Cox proportional hazards models.

RESULTS

Among 210 children, 21 developed AIDS and three died. Baseline characteristics of the 124 infants treated before 3 months were similar to those of the 86 infants treated later. The risk of developing AIDS/death at 1 year was 1.6 and 11.7% in the two groups, respectively (P < 0.001). Deferring treatment was associated with increased risk of progression [crude hazard ratio 5.0; 95% confidence interval (CI) 2.0-12.6; P = 0.001] that persisted after adjusting for cohort in multivariate models (adjusted hazard ratio 3.0; 95% CI 1.2-7.9; P = 0.021).

CONCLUSION

In HIV-1 vertically infected infants, starting antiretroviral therapy before the age of 3 months is associated with a significant reduction in progression to AIDS and death.

Delayed early antiretroviral treatment is associated with an HIV-specific long-term cellular response in HIV-1 vertically infected infants

Antiviral T-cell immune responses appear to be crucial to control HIV replication. Infants treated before the third month of life with highly active antiretroviral treatment (HAART) did not develop a persistent HIV-specific immune response. We evaluated how delayed initiation of HAART after 3 months of age influences the development of HIV-1-specific T-cell responses during long-term follow-up in 9 HIV-1 vertically infected infants. These data suggest that a longer antigenic stimulation, due to a larger window for therapeutic intervention with HAART, is associated with the establishment of a persistent specific HIV immune response resulting in a long-term viral control of vertically infected infants.

Effective highly active antiretroviral therapy in patients with primary HIV-1 infection prevents the evolution of the avidity of HIV-1-specific antibodies

OBJECTIVE

To evaluate if the administration of highly active antiretroviral therapy (HAART) during primary HIV infection (PHI) may affect the antibody avidity evolution.

METHODS

In 13 subjects with symptomatic PHI, of whom 8 initiated HAART at diagnosis, the Avidity Index (AI) and Western blot evolution patterns were analyzed on serial serum/plasma samples for 1 year. In 4 patients, who subsequently interrupted HAART, additional specimens were analyzed.

RESULTS

At diagnosis, the range of HIV viremia was 0.003 to 38 x 10(6) copies/mL. In untreated patients, viremia reached the set point in 4 to 6 months, whereas in treated patients, early suppression of viremia was observed, remaining undetectable during therapy. At diagnosis, the median AI was low in untreated (0.42, range: 0.33 to 0.43) and treated (0.44, range: 0.40 to 0.72) patients. At 3, 6, and 12 months, the AI progressively increased in untreated patients, whereas it remained <0.80 in all treated patients. In the 4 patients interrupting HAART, the AI increased after therapy interruption to greater than 0.80 in < or = 6 months. The Western blot pattern transiently/partially reversed during HAART in 2 patients.

CONCLUSIONS

Antibody avidity maturation takes place only in the presence of ongoing viral replication. These results may have relevant implications in understanding the complex mechanism of maturation of the immune response to HIV.

Early response to highly active antiretroviral therapy in HIV-1-infected Kenyan children

OBJECTIVES

To describe the early response to World Health Organization (WHO)-recommended nonnucleoside reverse transcriptase inhibitor (NNRTI)-based first-line highly active antiretroviral therapy (HAART) in HIV-1-infected Kenyan children unexposed to nevirapine.

DESIGN

Observational prospective cohort.

METHODS

HIV-1 RNA level, CD4 lymphocyte count, weight for age z score, and height for age z score were measured before the initiation of HAART and every 3 to 6 months thereafter. Children received no nutritional supplements.

RESULTS

Sixty-seven HIV-1-infected children were followed for a median of 9 months between August 2004 and November 2005. Forty-seven (70%) used zidovudine, lamivudine (3TC), and an NNRTI (nevirapine or efavirenz), whereas 25% used stavudine (d4T), 3TC, and an NNRTI. Nevirapine was used as the NNRTI by 46 (69%) children, and individual antiretroviral drug formulations were used by 63 (94%), with only 4 (6%) using a fixed-dose combination of d4T, 3TC, and nevirapine (Triomune; Cipla, Mumbai, India). In 52 children, the median height for age z score and weight for age z score rose from -2.54 to -2.17 (P<0.001) and from -2.30 to -1.67 (P=0.001), respectively, after 6 months of HAART. Hospitalization rates were significantly reduced after 6 months of HAART (17% vs. 58%; P<0.001). The median absolute CD4 count increased from 326 to 536 cells/microL (P<0.001), the median CD4 lymphocyte percentage rose from 5.8% before treatment to 15.4% (P<0.001), and the median viral load fell from 5.9 to 2.2 log10 copies/mL after 6 months of HAART (P<0.001). Among 43 infants, 47% and 67% achieved viral suppression to less than 100 copies/mL and 400 copies/mL, respectively, after 6 months of HAART.

CONCLUSION

Good early clinical and virologic response to NNRTI-based HAART was observed in HIV-1-infected Kenyan children with advanced HIV-1 disease.

Effectiveness of early initiation of protease inhibitor-sparing antiretroviral regimen in human immunodeficiency virus-1 vertically infected infants

Each of the 17 vertically infected infants born to HIV-1-infected mothers in Belgian HIV reference centers since 1996 was treated with a combination of 3 reverse transcription inhibitors as soon as the diagnosis was established. Treatment was initiated in all patients before 66 days of life. Twelve patients, including 11/13 infants treated with the combination of zidovudine, lamivudine and nevirapine, experienced a complete viral suppression (<50 copies/mL) with their first drug regimen. At last follow-up, 12 patients were asymptomatic, 2 were CDC stage A and 3 were stage B; 15 had HIV-1 RNA levels of <50 copies/mL and 14 had >or=25% CD4 lymphocytes. These results suggest that early initiation of treatment with 3 reverse transcription inhibitors is highly effective to inhibit viral replication and to prevent clinical and immunologic progression of HIV infection in vertically infected infants.

Recommendations in pediatric antiretroviral therapy

The pathogenesis of HIV infection and the general principles of therapy are the same for HIV-infected adults, adolescents, children and infants. However, antiretroviral treatment of HIV infection in pediatrics requires the consideration of a number of factors specific to its population, including differences in drug pharmacokinetics and the use of virologic and immunologic markers, as well as age-related adherence issues. This review summarizes the text of the Guidelines for the Use of Antiretroviral Agents in Pediatric HIV Infection, which was updated in October 2006. The guidelines are the work of the Working Group on Antiretroviral Therapy and Medical Management of HIV-Infected Children, a group of the Office of AIDS Research Advisory Council of the National Institutes of Health, which reviews new data on an ongoing basis and provides regular updates to the guidelines. As these guidelines were developed for the US, they may not be applicable in other countries. This summary does not attempt to place the Working Group guidelines in the context of international guidelines, nor does it attempt to detail the use of antiretroviral medication in the prevention of perinatal transmission of HIV, such as addressing the use of zidovudine versus single-dose nevirapine.

Disease Progression Among HIV-Infected Children Who Receive Perinatal Zidovudine Prophylaxis

BACKGROUND

Studies of perinatal HIV infection have reported mixed results regarding the prognosis of HIV-infected infants exposed to perinatal zidovudine prophylaxis (PZP).

METHODS

We have followed a population-based cohort of children with perinatal HIV infection to evaluate whether early HIV disease progression was more common among those who received PZP and whether subsequent antiretroviral therapy (ART) was less effective in preventing early disease progression.

RESULTS

We identified 73 children with perinatal HIV infection born between 1994 and 2001 with at least 3 years of follow-up and with information concerning PZP administration. Children who received PZP started subsequent ART at an earlier age than those who did not receive PZP (median age at starting treatment: 2 months for PZP vs. 6 months for no PZP; P = 0.0002). PZP was associated with decreased early HIV progression: 21% (7 of 33) of children who received PZP progressed to a category C diagnosis by 3 years compared with 45% (18 of 40) of children who did not receive PZP (P = 0.047). Children who did not receive PZP progressed to a category C diagnosis at a younger age than children who received PZP (median: 4 vs. 11 months; P = 0.061). ART was as effective in preventing early HIV progression in children who received PZP as in children who did not receive PZP.

CONCLUSIONS

In our population-based cohort of perinatally HIV-infected children, those who received PZP started ART at a significantly earlier age than those who did not receive PZP and also demonstrated decreased HIV disease progression by the age of 3 years.

Outcomes for human immunodeficiency virus-1-infected infants in the United kingdom and Republic of Ireland in the era of effective antiretroviral therapy

BACKGROUND

There are few data about disease progression and response to antiretroviral therapy (ART) in vertically HIV-infected infants in the era of effective therapy.

DESIGN

Cohort study.

METHODS

We examined progression to acquired immunodeficiency syndrome (AIDS) and death over calendar time for infants reported to the National Study of HIV in Pregnancy and Childhood in the United Kingdom/Ireland. The use of ART and CD4 and HIV-1 RNA responses were assessed in a subset in the Collaborative HIV Pediatric Study.

RESULTS

Among 481 infants, mortality was lower in those born after 1997 (HR 0.30; P < 0.001), with no significant change in progression to AIDS. Of 174 infants born since 1997 in the Collaborative HIV Pediatric Study, 41 (24%) were followed from birth, 77 (44%) presented pre-AIDS and 56 (32%) presented with AIDS. Of 125 (72%) children on 3- or 4-drug ART by the age of 2 years, 59% had HIV-1 RNA <400 at 12 months; median CD4 percentage increased from 24% to 35%. Among 41 infants followed from birth, 12 progressed to AIDS (5 while ART naive) and 3 died; 1 of 10 infants initiating ART before 3 months of age progressed clinically.

CONCLUSION

Mortality in HIV-infected infants is significantly lower in the era of effective ART, but symptomatic disease rates remain high. Infrequent clinic attendance and poor compliance with cotrimoxazole prophylaxis and/or ART in infants born to diagnosed HIV-infected women and late presentation of infants identified after birth appear to be major contributors. Poor virologic response to ART during infancy is of concern because of increased likelihood of early development of resistance.

Virologic, immunologic, and clinical benefits from early combined antiretroviral therapy in infants with perinatal HIV-1 infection

OBJECTIVE

To investigate the impact of early versus deferred combined antiretroviral treatment (ART) in asymptomatic or moderately symptomatic [Centers for Disease Control and Prevention (CDC) category N, A or B] infants with perinatal HIV-1 infection.

METHODS

A multi-centre nationwide case-control study was conducted. Data from 30 infants treated with combined ART with three or more drugs before 6 months of age were compared with data from 103 infants starting ART with three or more drugs after 6 months of age. The median follow-up time was 4.1 years (range, 1.0-6.5 years).

RESULTS

No difference was evident in the first available viral load and CD4 T-lymphocyte percentage between the two groups of children. Early-treated infants showed significantly lower viral loads than infants receiving deferred treatment at all the follow-up periods. A higher proportion of early-treated infants than infants receiving deferred treatment (73.3% versus 30.1%; P < 0.0001) reached an undetectable viral load. Higher CD4 T-lymphocyte percentages were found in early-treated infants at 13-24 (P < 0.0001), 25-36 (P < 0.0001), and 37-48 (P = 0.003) months of age. No early-treated infant versus 20 of 103 (19.4%) infants receiving deferred ART (P = 0.02) showed a CD4 T-lymphocyte percentage of less than 15% at one time point during follow-up. No CDC category A, B or C clinical event occurred in early-treated infants over the follow-up period while 44 of 103 (42.7%) infants receiving deferred treatment presented a decline in the CDC category. Kaplan-Meier analyses revealed significant differences in CDC category A (P = 0.0002), B (P = 0.0003), and C (P = 0.0018) event-free survivals.

CONCLUSION

The data suggest virologic, immunologic, and clinical benefits from early administration of ART.

Perinatally Acquired HIV-1 Infection: Prevention and Evaluation of HIV-Exposed Infants

Perinatal transmission of human immunodeficiency virus type 1 (HIV-1) is the primary cause of pediatric HIV infections. In recent years, perinatal HIV-1 transmission rates in the United States have declined markedly because of several factors that include enhanced voluntary counseling and HIV-1 testing (VCT) for pregnant women, widespread use of antiretroviral prophylaxis or combination antiretroviral therapy, avoidance of breastfeeding, and elective cesarean delivery. However, perinatal transmission of HIV-1 still occurs, and 300 to 400 infected infants are born annually, primarily because of missed prevention opportunities. The pediatrician plays a vital role in the prevention of perinatal transmission of HIV-1 by identifying newborns born to infected mothers who were not tested during pregnancy, administering antiretroviral prophylaxis, and ensuring follow-up to confirm or exclude the diagnosis of HIV-1 infection in early infancy. This article reviews recent advances in the prevention of perinatal transmission of HIV-1, discusses evaluation and treatment of infants exposed to HIV-1, and highlights certain unique features of HIV-1 infections in infants, with a focus on early diagnosis, clinical manifestations, treatment, and prognosis.

Triple nucleoside reverse transcriptase inhibitor therapy in children

Much of the success attributed to HIV therapy in the last few years has resulted from improved ways of using existing drugs in combination therapy regimens. The availability of new, more potent drugs such as protease inhibitors and more accurate viral load tests to aid decisions to start or change treatment has also contributed to the success. Published recommendations for pediatric HIV therapy, generated by a panel of experts and specialists, are readily available and regularly updated. Preferred regimens of 'potent' therapy (referred to as highly active antiretroviral therapy, or HAART) currently consist of two nucleoside reverse transcriptase inhibitors (NRTIs) combined with either a non-nucleoside reverse transcriptase inhibitor (NNRTI) or a protease inhibitor. More intense four-drug regimens using an NNRTI or a second protease inhibitor as a fourth drug are being evaluated. Problems with HAART include: unpalatable drug formulations and adverse effects, coupled with lack of data on the pharmacokinetics, efficacy, and safety of various drug combinations. Adherence is a major factor influencing the efficacy and outcome of antiretroviral therapy. Many children cannot adhere to complex multidrug regimens, which cause virologic failure, despite excellent CD4+ cell count responses. This means a rapid progression through the limited number of treatment regimens available. Simpler regimens such as those containing three NRTIs have been proposed as a method of treatment that will allow suppression of the virus, yet circumvent many of the problems previously mentioned. An additional benefit would be the preservation of antiretroviral drugs from other classes for future treatment options if required. The major advantages of triple NRTI regimens are the simplicity of the regimen, good tolerability, few drug-drug interactions, and infrequent adverse effects coupled with a low pill burden. However, abacavir hypersensitivity remains a major problem. Up to 3% of patients may develop an early idiosyncratic hypersensitivity reaction - fever, malaise, and mucositis with or without rash, which can progress to more advanced stages of shock and death. A major concern is the apparently inferior virologic control of triple NRTI therapy as demonstrated in the AIDS Clinical Trials Group A5095 study with zidovudine/lamivudine/abacavir (Trizivir) combination in adults. Such a combination should only be considered in special situations. Examples cited include informed patient choice based on anticipated poor adherence on other treatment regimens, or if concomitant drugs such as tuberculosis medication are prescribed. The low pill burden of triple NRTI regimens (especially if combined in a single pill such as Trizivir), offers hope that regimen simplification may still be possible in the future.

A trial of three antiretroviral regimens in HIV-1-infected children

BACKGROUND

Depletion of CD4 T-cell counts or progression of human immunodeficiency virus (HIV) disease occurs rapidly in children, but few data address the efficacy of aggressive therapy for HIV-infected children.

METHODS

We evaluated the safety, tolerability, and activity of three regimens of antiretroviral therapy in a multicenter, open-label, phase 1-2 trial. Children infected with HIV type 1 (HIV-1) were stratified at entry according to age--three months or younger (early therapy) or older than three months (delayed therapy)--and assigned sequentially to one of three regimens. Children continued to receive treatment for up to 200 weeks if the plasma HIV-1 RNA level was less than 1000 copies per milliliter by 16 weeks.

RESULTS

Plasma HIV-1 RNA levels fell from a median of 5.3 log copies per milliliter (range, 3.3 to 6.4 log copies per milliliter) at baseline to less than 1000 copies per milliliter at 16 weeks in 32 of 52 infants (62 percent). Plasma HIV-1 RNA levels were below 400 copies per milliliter at 48 weeks in 26 infants (50 percent) and at 200 weeks in 23 infants (44 percent). An intention-to-treat analysis revealed that significantly more children who received stavudine, lamivudine, nevirapine, and nelfinavir had plasma HIV-1 RNA levels of less than 400 copies per milliliter at 48 weeks (83 percent) and 200 weeks (72 percent) than children who received reverse-transcriptase inhibitors alone (P=0.001 and P=0.01, respectively). Fewer infants in the delayed-therapy group than in the early-therapy group (30 percent vs. 60 percent) had plasma HIV-1 RNA levels of less than 400 copies per milliliter at 200 weeks (P=0.03). Treatment-associated adverse effects were infrequent.

CONCLUSIONS

In this phase 1-2 trial involving HIV-1-infected children, an age of three months or younger at the initiation of therapy and treatment with stavudine, lamivudine, nevirapine, and nelfinavir were associated with improved long-term viral suppression. Larger, randomized trials are required to define the optimal time to initiate therapy and the optimal regimen for these infants.

Principles of antiretroviral treatment of children and adolescents with human immunodeficiency virus infection

Human immunodeficiency virus (HIV) infection requires life-long therapy to attain durable suppression of HIV replication and prevent or reverse HIV-related symptoms or immune system dysfunction. Combination therapy with 3 or more antiretroviral medications is currently widely recommended for treatment of children and adolescents with HIV infection. While potent regimens can initially reduce virus load to below assay quantitation limits in the majority of persons with HIV infection, 30% to 80% of children will have regimen failure and return of detectable plasma virus within 1 year. Adherence to therapy is critical to regimen success. Optimal treatment requires careful use of potent combinations of drugs, with attention to adherence, palatability, toxicity, and pharmacokinetics. Practitioners with experience caring for children and adolescents with HIV infection should be involved.

PENTA guidelines for the use of antiretroviral therapy in paediatric HIV infection. Pediatric European Network for Treatment of AIDS

OBJECTIVE

To produce European Guidelines for the use of antiretroviral therapy (ART) in HIV-infected children.

DESIGN

Systematic literature review using Medline, the major antiretroviral conference reports, and IDSA recommendations on guideline production.

SETTING

Pediatric European Network for Treatment of AIDS (PENTA) Steering Committee.

OUTCOME MEASURE

Guidelines have been produced for the use of antiretroviral therapy in HIV-infected children in Europe. Recommendations on when to start ART and which ART to start, with dosages and a summary of the relevant literature, have been produced.

CONCLUSIONS

These guidelines are aimed at assisting paediatricians in Europe with ART prescribing, and provide a more cautious approach to starting therapy than current paediatric USA guidelines.

Early multitherapy including a protease inhibitor for human immunodeficiency virus type 1-infected infants

BACKGROUND

To assess tolerance and efficacy of early multitherapy including a protease inhibitor for infants perinatally infected with HIV.

METHODS

Observational study of tolerance and clinical and immunovirologic evolution in HIV-infected infants treated before the age of 1 year in the French Perinatal Study.

RESULTS

Thirty-one infants were included. The median age was 3.7 months at initiation of multitherapy. Clinical stage was C (n = 8), B (n = 5) or A/N (n = 18). The median HIV RNA viral load was 5.8 log copies/ml, and the median CD4 cell percentage was 29%. Median follow-up of treatment was 27 months. Of 31 infants 15 experienced mild to moderate adverse events. No infant had clinical or immunologic progression. The median change in viral load was -2.7 log copies/ml after 3 months, -2.0 log after 12 months and -1.7 log after 24 months of treatment. The proportion of infants with a viral load below 500 copies/ml decreased from 53% at 6 months to 18% at 24 months of treatment. The virologic response was not correlated with viral load at baseline. However, the slope of the viral load decrease during the first month of treatment was predictive of the virologic response at 3 and 6 months. Fourteen infants with a viral load of >500 copies/ml after 6 months of treatment displayed viruses with antiretroviral resistance mutations in reverse transcriptase and/or protease genes.

CONCLUSIONS

Despite the absence of clinical or immunologic progression, the high frequency of virologic failure associated with genotypic resistance reveals the difficulties associated with implementing antiretroviral multitherapy in infants. Suboptimal doses of protease inhibitor could be a factor contributing to treatment failure.

Efficacy of highly active antiretroviral therapy in HIV-1 infected children

Although the reduction in HIV-1-related deaths with highly active antiretroviral therapy (HAART) is similar in adults and children, the extent of the changes in two important surrogate markers HIV-1 RNA levels and CD4+ T cell counts, differs widely. In most paediatric studies virological response rates to HAART are inferior to those in adults. This review provides an overview of the paediatric clinical studies using HAART and seeks to improve the understanding of factors that may contribute to success or failure of HAART in children. An overview of all current articles on paediatric clinical trials using HAART is provided. 23 papers were available. HIV-1 RNA loads and CD4+ T cell counts were used as primary outcome measures. Virological response rates were highly variable, both among the different antiretroviral drugs but also among different studies using the same medication. Four studies in which dosages of the administrated protease inhibitor (PI) were adjusted after pharmacokinetic evaluation had superior virological response rates compared with those in which fixed dosages were used. Immunological response rates were more uniform than virological responses. In almost all studies increases of CD4+ T cell counts are reported independent of the extent of the virological response. Side-effects of HAART were generally mild, transient, and of gastrointestinal origin. Significant percentages of patients with serum lipid abnormalities were reported in three paediatric studies. However, signs of clinical lipodystrophy were not observed. The inferior virological response rates, which have been reported in HIV-1 infected children treated with HAART form a reflection of the challenges that are encountered in the treatment of these children. Difficulties with adherence and with the pharmacokinetics of PIs in children require an intensive, child-adjusted approach. A practical approach to therapy in institutions without tertiary care facilities may be induction therapy with a lopinavir containing regimen (lacking a need for therapeutic drug monitoring), to reduce high viral load levels followed by an easily tolerated maintenance regimen, for example containing abacavir or nevirapine.