Efficacy and tolerability of nevirapine- versus efavirenz-containing regimens in HIV-infected Thai children

Clinical, Immunological and Virological Responses of Zidovudine-Lamivudine-Nevirapine versus Zidovudine-Lamivudine-Efavirenz Antiretroviral Treatment (ART) Among HIV-1 Infected Children: Asella Teaching and Referral Hospital, South-East Ethiopia

Background:

Antiretroviral Therapy(ART) remarkably reduced HIV-1 infection-related mortality in children. The efficacy and safety of different ART regimen in pediatric age groups remained issues of debates and available evidence were scarce especially among children taking the of one the two prototypes (NVP or EFV) Non-Nucleoside Reverse Transcriptase Inhibitor(NNRTI) as backbone of ART regimen.

Therefore, the objective of this study was to compare clinical, immunological and virological responses of zidovudine-lamivudine-nevirapine (AZT+3TC+ NVP) versus zidovudine-lamivudine-efavirenz (AZT+3TC+EFV) ART regimen among HIV-1 infected children.

Methods:

A retrospective cross-sectional study was done by reviewing medical records of the patients to evaluate clinical, immunological and virological outcomes of NVP+AZT+3TC versus EFV+AZT+3TC ART regimen among HIV-1 infected children. Data were entered into Epi-info version 7.2.2 for clean up and exported to SPSS version 17 for analysis. Paired and Independent t-tests were used to compare the CD4 cell count, weight and virologic level at six months with corresponding baseline value; and the mean weight, CD4 gain and viral suppression across the two ART regimens at six months of ART respectively.

Results:

Medical records of 122 patients from NVP-based regimen and 61 patients from EFV group were reviewed. After six months of NVP+AZT+3TC treatment, the mean CD4 cell count difference from baseline was 215(95% CI, 175.414-245.613, p<0.001). From EFV+AZT+3TC group, the mean CD4 cell count difference from baseline was 205(95% CI 155.404-235.623, p< 0.001). The mean CD4 count difference between the two regimens was comparable (p 0.145). Similarly, optimal viral suppression was achieved in 82% (100/122) of NVP+AZT+3TC regimen and 83% (44/61) of EFV+AZT+3TC regimen which was still comparable across the two groups.

Conclusion:

There was no difference in clinical, immunological and virological outcomes among patients taking NVP+AZT+3TC or EFV+AZT+3TC ART regimen.

Thai national guidelines for the use of antiretroviral therapy in pediatric HIV infection in 2010

With better knowledge and availability of antiretroviral treatments, the Thai National HIV Guidelines Working Group has issued treatment guidelines for children in Thailand in March 2010. The most important aspects of these new guidelines are detailed below. ART should be initiated in infants less than 12 months of age at any CD4 level regardless of symptoms and in all children at CDC clinical stage B and C or WHO clinical stages 3 and 4. For children with no or mild symptoms consider CD4-guided thresholds of CD4 <25% (children aged one to five years) or CD4 <350 cells/mm3 (children 5 years or older). The preferred first-line regimen in children aged < 3 years is AZT+3TC+NVP. For children >3 years of age the preferred regimen is AZT+3TC+EFV. If an infant has previously been exposed to NVP perinatally, use AZT+3TC+LPV/r as empirical first regimen. In adolescents, consider TDF+3TC+EFV. The preferred ARV treatment in children who failed first line regimens of 2NRTI+NNRTI (Salvage treatment) comprises 2NRTI (guided by genotype) +LPV/r, and an alternative regimen is 2NRTI (guided by genotype) +ATV/ r (use in cases with dyslipidemia who are six years or older). In cases with extensive NRTI resistance with no effective NRTI option available, double boosted PI with LPV/r+SQV or LPV/r+IDV can be considered. Consultation with an expert is recommended. Laboratory monitoring is recommended for CD4 and every six months. Viral load at least at 6 and 12 months after initiation or change of regimen, then yearly thereafter. More frequent viral load monitoring is advised for cases with unsuccessful virologic response, infants, children with imperfect adherence, or those using of third line regimens. Toxicity monitoring depends on the drug received, at least every six months, and more often as clinically indicated. These include, but are not limited to, complete blood count, renal function tests, liver function tests, urinanalysis, and lipid profiles. Therapeutic drug monitoring is recommended in cases that have ARV-related toxicity, receiving non-standard dosing or regimens, using double boosted PI, and in those with renal or hepatic impairment.

Hepatic, Renal, Hematologic, and Inflammatory Markers in HIV-Infected Children on Long-term Suppressive Antiretroviral Therapy

BACKGROUND

Data on long-term toxicity of antiretroviral therapy (ART) in HIV-infected children are sparse. PENPACT-1 was an open-label trial in which HIV-infected children were assigned randomly to receive protease inhibitor (PI)- or nonnucleoside reverse-transcriptase inhibitor (NNRTI)-based ART.

METHODS

We examined changes in clinical, immunologic, and inflammatory markers from baseline to year 4 in the subset of children in the PENPACT-1 study who experienced viral suppression between week 24 and year 4 of ART. Liver enzyme, creatinine, and cholesterol levels and hematologic parameters were assessed during the trial. Cystatin C, high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6), d-dimer, and soluble CD14 (sCD14) were assayed from cryopreserved specimens.

RESULTS

Ninety-nine children (52 on PI-based and 47 on NNRTI-based ART) met inclusion criteria. The median age at initiation of ART was 6.5 years (interquartile range [IQR], 3.7-13.4 years), and 22% were aged <3 years at ART initiation; 56% of the PI-treated children received lopinavir/ritonavir, and 70% of NNRTI-treated children received efavirenz initially. We found no evidence of significant clinical toxicity in either group; growth, liver, kidney, and hematologic parameters either remained unchanged or improved between baseline and year 4. Total cholesterol levels increased modestly, but no difference between the groups was found. IL-6 and hs-CRP levels decreased more after 4 years in the NNRTI-based ART group. The median change in IL-6 level was -0.35 pg/ml in the PI-based ART group and -1.0 in the NNRTI-based ART group (P = .05), and the median change in hs-CRP level was 0.25 µg/ml in the PI-based ART group and -0.95 µg/ml in the NNRTI-based ART group (P = .005).

CONCLUSION

These results support the safety of prolonged ART use in HIV-infected children and suggest that suppressive NNRTI-based regimens can be associated with lower levels of systemic inflammation.

Determinants of virological outcome and adverse events in African children treated with paediatric nevirapine fixed-dose-combination tablets

BACKGROUND

Nevirapine is the only nonnucleoside reverse transcriptase inhibitor currently available as a paediatric fixed-dose-combination tablet and is widely used in African children. Nonetheless, the number of investigations into pharmacokinetic determinants of virological suppression in African children is limited, and the predictive power of the current therapeutic range was never evaluated in this population, thereby limiting treatment optimization.

METHODS

We analysed data from 322 African children (aged 0.3-13 years) treated with nevirapine, lamivudine, and either abacavir, stavudine, or zidovudine, and followed up to 144 weeks. Nevirapine trough concentration (Cmin) and other factors were tested for associations with viral load more than 100 copies/ml and transaminase increases more than grade 1 using proportional hazard and logistic models in 219 initially antiretroviral treatment (ART)-naive children.

RESULTS

Pre-ART viral load, adherence, and nevirapine Cmin were associated with viral load nonsuppression [hazard ratio = 2.08 (95% confidence interval (CI): 1.50-2.90, P < 0.001) for 10-fold higher pre-ART viral load, hazard ratio = 0.78 (95% CI: 0.68-0.90, P < 0.001) for 10% improvement in adherence, and hazard ratio = 0.94 (95% CI: 0.90-0.99, P = 0.014) for a 1 mg/l increase in nevirapine Cmin]. There were additional effects of pre-ART CD4 cell percentage and clinical site. The risk of virological nonsuppression decreased with increasing nevirapine Cmin, and there was no clear Cmin threshold predictive of virological nonsuppression. Transient transaminase elevations more than grade 1 were associated with high Cmin (>12.4 mg/l), hazard ratio = 5.18 (95% CI 1.95-13.80, P < 0.001).

CONCLUSION

Treatment initiation at lower pre-ART viral load and higher pre-ART CD4 cell percentage, increased adherence, and maintaining average Cmin higher than current target could improve virological suppression of African children treated with nevirapine without increasing toxicity.

Efavirenz or nevirapine in three-drug combination therapy with two nucleoside or nucleotide-reverse transcriptase inhibitors for initial treatment of HIV infection in antiretroviral-naïve individuals

BACKGROUND

The advent of highly active antiretroviral therapy (ART) has reduced the morbidity and mortality due to HIV infection. The World Health Organization (WHO) ART guidelines focus on three classes of antiretroviral drugs, namely nucleoside or nucleotide reverse transcriptase inhibitors (NRTI), non-nucleoside reverse transcriptase inhibitors (NNRTI) and protease inhibitors. Two of the most common medications given as first-line treatment are the NNRTIs, efavirenz (EFV) and nevirapine (NVP). It is unclear which NNRTI is more efficacious for initial therapy. This systematic review was first published in 2010.

OBJECTIVES

To determine which non-nucleoside reverse transcriptase inhibitor, either EFV or NVP, is more effective in suppressing viral load when given in combination with two nucleoside reverse transcriptase inhibitors as part of initial antiretroviral therapy for HIV infection in adults and children.

SEARCH METHODS

We attempted to identify all relevant studies, regardless of language or publication status, in electronic databases and conference proceedings up to 12 August 2016. We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov to 12 August 2016. We searched LILACS (Latin American and Caribbean Health Sciences Literature) and the Web of Science from 1996 to 12 August 2016. We checked the National Library of Medicine (NLM) Gateway from 1996 to 2009, as it was no longer available after 2009.

SELECTION CRITERIA

We included all randomized controlled trials (RCTs) that compared EFV to NVP in people with HIV without prior exposure to ART, irrespective of the dosage or NRTI's given in combination.The primary outcome of interest was virological success. Other primary outcomes included mortality, clinical progression to AIDS, severe adverse events, and discontinuation of therapy for any reason. Secondary outcomes were change in CD4 count, treatment failure, development of ART drug resistance, and prevention of sexual transmission of HIV.

DATA COLLECTION AND ANALYSIS

Two review authors assessed each reference for inclusion using exclusion criteria that we had established a priori. Two review authors independently extracted data from each included trial using a standardized data extraction form. We analysed data on an intention-to-treat basis. We performed subgroup analyses for concurrent treatment for tuberculosis and dosage of NVP. We followed standard Cochrane methodological procedures.

MAIN RESULTS

Twelve RCTs, which included 3278 participants, met our inclusion criteria. None of these trials included children. The length of follow-up time, study settings, and NRTI combination drugs varied greatly. In five included trials, participants were receiving concurrent treatment for tuberculosis.There was little or no difference between EFV and NVP in virological success (RR 1.04, 95% CI 0.99 to 1.09; 10 trials, 2438 participants; high quality evidence), probably little or no difference in mortality (RR 0.84, 95% CI 0.59 to 1.19; 8 trials, 2317 participants; moderate quality evidence) and progression to AIDS (RR 1.23, 95% CI 0.72 to 2.11; 5 trials, 2005 participants; moderate quality evidence). We are uncertain whether there is a difference in all severe adverse events (RR 0.91, 95% CI 0.71 to 1.18; 8 trials, 2329 participants; very low quality evidence). There is probably little or no difference in discontinuation rate (RR 0.93, 95% CI 0.69 to 1.25; 9 trials, 2384 participants; moderate quality evidence) and change in CD4 count (MD -3.03; 95% CI -17.41 to 11.35; 9 trials, 1829 participants; moderate quality evidence). There may be little or no difference in treatment failure (RR 0.97, 95% CI 0.76 to 1.24; 5 trials, 737 participants; low quality evidence). Development of drug resistance is probably slightly less in the EFV arms (RR 0.76, 95% CI 0.60 to 0.95; 4 trials, 988 participants; moderate quality evidence). No studies were found that looked at sexual transmission of HIV.When we examined the adverse events individually, EFV probably is associated with more people with impaired mental function (7 per 1000) compared to NVP (2 per 1000; RR 4.46, 95% CI 1.65 to 12.03; 6 trials, 2049 participants; moderate quality evidence) but fewer people with elevated transaminases (RR 0.52, 95% CI 0.35 to 0.78; 3 trials, 1299 participants; high quality evidence), fewer people with neutropenia (RR 0.48, 95% CI 0.28 to 0.82; 3 trials, 1799 participants; high quality evidence), and probably fewer people withrash (229 per 100 with NVP versus 133 per 1000 with EFV; RR 0.58, 95% CI 0.34 to 1.00; 7 trials, 2277 participants; moderate quality evidence). We found that there may be little or no difference in gastrointestinal adverse events (RR 0.76, 95% CI 0.48 to 1.21; 6 trials, 2049 participants; low quality evidence), pyrexia (RR 0.65, 95% CI 0.15 to 2.73; 3 trials, 1799 participants; low quality evidence), raised alkaline phosphatase (RR 0.65, 95% CI 0.17 to 2.50; 1 trial, 1007 participants; low quality evidence), raised amylase (RR 1.40, 95% CI 0.72 to 2.73; 2 trials, 1071 participants; low quality evidence) and raised triglycerides (RR 1.10, 95% CI 0.39 to 3.13; 2 trials, 1071 participants; low quality evidence). There was probably little or no difference in serum glutamic oxaloacetic transaminase (SGOT; MD 3.3, 95% CI -2.06 to 8.66; 1 trial, 135 participants; moderate quality evidence), serum glutamic- pyruvic transaminase (SGPT; MD 5.7, 95% CI -4.23 to 15.63; 1 trial, 135 participants; moderate quality evidence) and raised cholesterol (RR 6.03, 95% CI 0.75 to 48.78; 1 trial, 64 participants; moderate quality evidence).Our subgroup analyses revealed that NVP slightly increases mortality when given once daily (RR 0.34, 95% CI 0.13 to 0.90; 3 trials, 678 participants; high quality evidence). There were little or no differences in the primary outcomes for patients who were concurrently receiving treatment for tuberculosis.

AUTHORS' CONCLUSIONS

Both drugs have similar benefits in initial treatment of HIV infection when combined with two NRTIs. The adverse events encountered affect different systems, with EFV more likely to cause central nervous system adverse events and NVP more likely to raise transaminases, cause neutropenia and rash.

Safety and effectiveness of combination antiretroviral therapy during the first year of treatment in HIV-1 infected Rwandan children: a prospective study

Background

With increased availability of paediatric combination antiretroviral therapy (cART) in resource limited settings, cART outcomes and factors associated with outcomes should be assessed.

Methods

HIV-infected children <15 years of age, initiating cART in Kigali, Rwanda, were followed for 18 months. Prospective clinical and laboratory assessments included weight-for-age (WAZ) and height-for-age (HAZ) z-scores, complete blood cell count, liver transaminases, creatinine and lipid profiles, CD4 T-cell count/percent, and plasma HIV-1 RNA concentration. Clinical success was defined as WAZ and WAZ >−2, immunological success as CD4 cells ≥500/mm³ and ≥25% for respectively children over 5 years and under 5 years, and virological success as a plasma HIV-1 RNA concentration <40 copies/mL.

Results

Between March 2008 and December 2009, 123 HIV-infected children were included. The median (interquartile (IQR) age at cART initiation was 7.4 (3.2, 11.5) years; 40% were <5 years and 54% were female. Mean (95% confidence interval (95%CI)) HAZ and WAZ at baseline were −2.01 (−2.23, −1.80) and −1.73 (−1.95, −1.50) respectively and rose to −1.75 (−1.98, −1.51) and −1.17 (−1.38, −0.96) after 12 months of cART. The median (IQR) CD4 T-cell values for children <5 and ≥5 years of age were 20% (13, 28) and 337 (236, 484) cells/mm³respectively, and increased to 36% (28, 41) and 620 (375, 880) cells/mm³. After 12 months of cART, 24% of children had a detectable viral load, including 16% with virological failure (HIV-RNA>1000 c/mL). Older age at cART initiation, poor adherence, and exposure to antiretrovirals around birth were associated with virological failure. A third (33%) of children had side effects (by self-report or clinical assessment), but only 9% experienced a severe side effect requiring a cART regimen change.

Conclusions

cART in Rwandan HIV-infected children was successful but success might be improved further by initiating cART as early as possible, optimizing adherence and optimizing management of side effects.

Etravirine in treatment-experienced, HIV-1-infected children and adolescents: 48-week safety, efficacy and resistance analysis of the phase II PIANO study

OBJECTIVES

PIANO (Paediatric study of Intelence As an NNRTI Option; TMC125-C213; NCT00665847) assessed the safety/tolerability, antiviral activity and pharmacokinetics of etravirine plus an optimized background regimen (OBR) in treatment-experienced, HIV-1-infected children (≥ 6 to < 12 years) and adolescents (≥ 12 to < 18 years) over 48 weeks.

METHODS

In a phase II, open-label, single-arm study, 101 treatment-experienced patients (41 children; 60 adolescents) with screening viral load (VL) ≥ 500 HIV-1 RNA copies/mL received etravirine 5.2 mg/kg (maximum dose 200 mg) twice a day (bid) plus OBR.

RESULTS

Sixty-seven per cent of patients had previously used efavirenz or nevirapine. At week 48, the most common treatment-related grade ≥ 2 adverse event (AE) was rash (13%); 12% experienced grade 3 AEs. Only two grade 4 AEs occurred (both thrombocytopaenia, not etravirine related). At week 48, 56% of patients (68% children; 48% adolescents) achieved a virological response (VL<50 copies/mL; intent-to-treat, noncompleter=failure). Factors predictive of response were adherence > 95%, male sex, low baseline etravirine weighted genotypic score and high etravirine trough concentration (C0h ). Seventy-six patients (75%) completed the trial; most discontinuations occurred because of protocol noncompliance or AEs (8% each). Sixty-five per cent of patients were > 95% adherent by questionnaire and 39% by pill count. Forty-one patients experienced virological failure (VF; time-to-loss-of-virological-response non-VF-censored algorithm) (29 nonresponders; 12 rebounders). Of 30 patients with VF with paired baseline/endpoint genotypes, 18 (60%) developed nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations, most commonly Y181C. Mean etravirine area under the plasma concentration-time curve over 12 h (AUC0-12h ; 5216 ng h/mL) and C0h (346 ng/mL) were comparable to adult target values.

CONCLUSIONS

Results with etravirine 5.2 mg/kg bid (with OBR) in this treatment-experienced paediatric population and etravirine 200 mg bid in treatment-experienced adults were comparable. Etravirine is an NNRTI option for treatment-experienced paediatric patients.

Association between efavirenz-based compared with nevirapine-based antiretroviral regimens and virological failure in HIV-infected children

IMPORTANCE

Worldwide, the nonnucleoside reverse transcriptase inhibitors (NNRTIs) efavirenz and nevirapine are commonly used in first-line antiretroviral regimens in both adults and children with human immunodeficiency virus (HIV) infection. Data on the comparative effectiveness of these medications in children are limited.

OBJECTIVE

To investigate whether virological failure is more likely among children who initiated 1 or the other NNRTI-based HIV treatment.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of children (aged 3-16 years) who initiated efavirenz-based (n = 421) or nevirapine-based (n = 383) treatment between April 2002 and January 2011 at a large pediatric HIV care setting in Botswana.

MAIN OUTCOMES AND MEASURES

The primary outcome was time from initiation of therapy to virological failure. Virological failure was defined as lack of plasma HIV RNA suppression to less than 400 copies/mL by 6 months or confirmed HIV RNA of 400 copies/mL or greater after suppression. Cox proportional hazards regression analysis compared time to virological failure by regimen. Multivariable Cox regression controlled for age, sex, baseline immunologic category, baseline clinical category, baseline viral load, nutritional status, NRTIs used, receipt of single-dose nevirapine, and treatment for tuberculosis.

RESULTS

With a median follow-up time of 69 months (range, 6-112 months; interquartile range, 23-87 months), 57 children (13.5%; 95% CI, 10.4%-17.2%) initiating treatment with efavirenz and 101 children (26.4%; 95% CI, 22.0%-31.1%) initiating treatment with nevirapine had virological failure. There were 11 children (2.6%; 95% CI, 1.3%-4.6%) receiving efavirenz and 20 children (5.2%; 95% CI, 3.2%-7.9%) receiving nevirapine who never achieved virological suppression. The Cox proportional hazard ratio for the combined virological failure end point was 2.0 (95% CI, 1.4-2.7; log rank P < .001, favoring efavirenz). None of the measured covariates affected the estimated hazard ratio in the multivariable analyses.

CONCLUSIONS AND RELEVANCE

Among children aged 3 to 16 years infected with HIV and treated at a clinic in Botswana, the use of efavirenz compared with nevirapine as initial antiretroviral treatment was associated with less virological failure. These findings may warrant additional research evaluating the use of efavirenz and nevirapine for pediatric patients.

Antiretroviral drug resistance profiles and response to second-line therapy among HIV type 1-infected Ugandan children

We sought to determine the pattern of resistance-associated mutations (RAMs) among HIV-1-infected children failing first-line antiretroviral therapy (ART) and ascertain their response to second-line regimens in 48 weeks of follow-up. The design involved a cohort study within an HIV care program. We studied records of 142 children on ART with virological failure to first-line ART and switched to second-line ART with prior genotypic resistance testing. The pattern of RAMs was determined in frequency runs and the factors associated with accumulation of≥3 thymidine analogue mutations (TAMs) and K103N were determined using multivariate logistic models. Changes in weight, height, CD4, and viral load at weeks 24 and 48 after switch to second-line therapy were determined using descriptive statistics. The children were mean age 10.9±4.6 years and 55.6% were male. The commonest nucleoside reverse transcriptase inhibitor (NRTI) RAM was M184V in 129/142 (90.8%) children. TAMs,≥3 TAMs, 69 insertion complex, K65R/N, and Q151M were observed in 43.0%, 10.6%, 18.3%, 2.8%, and 2.1% of the children, respectively. The commonest nonnucleoside reverse transcriptase inhibitor (NNRTI) RAM was K103N in 72/142 (50.7%) children. The starting ART regimen was associated with accumulation of both≥3 TAMs (p=0.046) and K103N (p<0.0001), while a history of poor adherence was associated with K103N accumulation (p=0.0388). After 24 weeks and 48 weeks of follow-up on lopinavir-ritonavir based second-line ART, 86/108 (79.6%) and 84.5% (87/103) of the children had viral loads<400 copies/ml, respectively. The mean CD4 absolute count increased by 173 cells/μl and 267cells/μl at weeks 24 and 48, respectively. Increments were also observed in mean weight (1.6 kg and 4.3 kg) and height (1.8 cm and 5.8 cm) at weeks 24 and 48, respectively. Multiple RAMs were observed among HIV-1-infected children with virological failure on first-line ART with M184V and K103N most frequent. The children responded favorably to boosted PI-based second-line ART.

Effectiveness of efavirenz-based regimens in young HIV-infected children treated for tuberculosis: a treatment option for resource-limited settings

BACKGROUND

Antiretroviral treatment (ART) options for young children co-infected with HIV and tuberculosis are limited in resource-poor settings due to limited data on the use of efavirenz (EFV). Using available pharmacokinetic data, an EFV dosing schedule was developed for young co-infected children and implemented as the standard of care at Macha Hospital in Southern Province, Zambia. Treatment outcomes in children younger than 3 years of age or weighing less than 10 kg receiving either EFV-based ART plus anti-tuberculous treatment or nevirapine-based (NVP) ART were compared.

METHODS

Treatment outcomes were measured in a cohort of HIV-infected children seeking care at Macha Hospital in rural Zambia from 2007 to 2010. Information on the diagnosis and treatment of tuberculosis was abstracted from medical records.

RESULTS

Forty-five children treated for tuberculosis initiated an EFV-based regimen and 69 children initiated a NVP-based regimen, 7 of whom also were treated for tuberculosis. Children receiving both regimens were comparable in age, but children receiving EFV started ART with a lower CD4(+) T-cell percentage and weight-for-age z-score. Children receiving EFV experienced increases in both CD4(+) T-cell percentage and weight-for-age z-score during follow-up, such that levels were comparable to children receiving NVP after two years of ART. Cumulative survival after 12 months of ART did not differ between groups (NVP:87%;EFV:80%;p = 0.25). Eleven children experienced virologic failure during follow-up.The adjusted hazard ratio of virologic failure comparing EFV to NVP was 0.25 (95% CI:0.05,1.24) and 0.13 (95% CI:0.03,0.62) using thresholds of 5000 and 400 copies/mL, respectively.Five children receiving EFV were reported to have had convulsions after ART initiation compared to only one child receiving NVP (p = 0.04).

CONCLUSIONS

Despite poorer health at ART initiation, children treated for tuberculosis and receiving EFV-based regimens showed significant improvements comparable to children receiving NVP-based regimens. EFV-based regimens should be considered for young HIV-infected children co-infected with tuberculosis in resource-limited settings.

Role of non-nucleoside reverse transcriptase inhibitors in treating HIV-infected children

The first-generation non-nucleoside reverse transcriptase inhibitors (NNRTIs), efavirenz and nevirapine, fulfil key roles in antiretroviral therapy for HIV-infected paediatric patients, from lowering the incidence of mother-to-child transmission during pregnancy and birth to treatment throughout childhood and adolescence. Both agents have established efficacy, safety and tolerability profiles, and also offer advantages over other classes of therapy in terms of regimen simplicity and availability across different treatment settings. Although the role of NNRTIs in paediatric treatment strategies is largely determined by experience in adult patients, results of the recent phase II/III PENPACT-1 trial in infants and children aged between 30 days and 18 years have shown that there are no significant differences in 4-year virological, immunological or clinical outcomes between NNRTIs and protease inhibitors as first- and second-line agents. However, results from the IMPAACT P1060 study (cohort 2), conducted in resource-limited settings, showed that infants under 36 months unexposed to NNRTIs were significantly more likely to fail treatment when started on a nevirapine-based regimen than those on a lopinavir/ritonavir-based regimen. Unfortunately, the use of efavirenz and nevirapine in children can be limited by rapid development of high-level resistance to one or both agents, which may reduce the availability of viable treatment options, particularly in resource-limited settings. Several therapeutic strategies addressing this issue are currently under investigation, but a significant need for new NNRTI-based treatment options remains. The more recently approved NNRTI, etravirine, has demonstrated efficacy and safety benefits in HIV-1-infected, NNRTI-resistant adult patients, with a higher genetic barrier to the development of resistance relative to the first-generation NNRTIs. Another NNRTI, rilpivirine (TMC278), is approved for use in HIV-1-infected, treatment-naïve adult patients and has demonstrated an improved tolerability profile compared with efavirenz. Although available data on etravirine in children are currently limited, ongoing trials will provide important information on the potential for their use in novel paediatric treatment strategies. This review examines the role of efavirenz and nevirapine in paediatric antiretroviral therapy in children within different treatment settings. In addition, this review also outlines available clinical data on etravirine and rilpivirine in the context of how these antiretrovirals may address some of the limitations of efavirenz and nevirapine in paediatric patients.

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.

Efavirenz or nevirapine in three-drug combination therapy with two nucleoside-reverse transcriptase inhibitors for initial treatment of HIV infection in antiretroviral-naïve individuals

BACKGROUND

The advent of highly active antiretroviral therapy (HAART) has reduced the morbidity and mortality due to HIV. The World Health Organisation (WHO) antiretroviral treatment (ART) guidelines focus on three classes of antiretroviral drugs, namely: nucleoside/nucleotide reverse transcriptase inhibitors (NRTI), non-nucleoside reverse transcriptase inhibitors (NNRTI) and protease inhibitors (PI). Two of the most common medications given in first-line treatment are the NNRTIs, efavirenz (EFV) and nevirapine (NVP). It is unclear which NNRTI is more efficacious for initial therapy.

OBJECTIVES

To determine which NNRTI, EFV or NVP, is more efficacious when given in combination with two NRTIs as part of initial ART for HIV infection in adults and children.

SEARCH STRATEGY

We used a comprehensive and exhaustive strategy in an attempt to identify all relevant studies, regardless of language or publication status, in electronic databases and conference proceedings from 1996 to 2009.

SELECTION CRITERIA

All randomised controlled trials comparing EFV to NVP in HIV-infected individuals without prior exposure to ART, irrespective of the dosage or NRTI backbone.The primary outcome of interest was virologic response to ART. Other primary outcomes included mortality, clinical progression, severe adverse events, and discontinuation of therapy for any reason. Secondary outcomes were immunologic response to ART, treatment failure, development of ART drug resistance, and prevention of sexual transmission of HIV.

DATA COLLECTION AND ANALYSIS

Two authors assessed each reference for inclusion and exclusion criteria established a priori. Data were abstracted independently using a standardised abstraction form. Data were analysed on an intention-to-treat basis and reported as per dosage of NVP.

MAIN RESULTS

We identified seven randomised controlled trials that met our inclusion criteria.The trials were pooled as per dosage of NVP. None of these trials included children.The seven trials enrolled 1,688 participants and found no critical differences between EFV and NVP, except for different toxicity profiles. EFV is more likely to cause central nervous system side-effects, while NVP is more likely to result in raised transaminases and neutropoenia. There was a higher mortality rate in the NVP 400mg once daily arm.The quality of literature to support these conclusions is moderate to high. Drug resistance was slightly less common with EFV than NVP, but the quality of this literature is low since only one of the seven studies reported on this outcome. No studies reported on sexual transmission of HIV. The length of follow-up time, study settings, and NRTI backbone varied greatly.

AUTHORS' CONCLUSIONS

Both drugs have equivalent efficacies in initial treatment of HIV infection when combined with two NRTIs, but different side effects.

Antiretroviral therapy outcomes of HIV-infected children in the TREAT Asia pediatric HIV observational database

INTRODUCTION

We report responses to combination antiretroviral therapy (cART) in the Therapeutics Research, Education, and AIDS Training in Asia Pediatric HIV Observational Database.

METHODS

Children included were those who had received cART (ie, ≥3 antiretrovirals) at <18 years. The analysis was intention-to-treat by the first cART regimen. Median values are provided with interquartile ranges; hazard ratios (HRs) with 95% confidence intervals.

RESULTS

Of the 1655 children included, 50.4% were male, with a median age at cART of 7.0 (3.9-9.8) years and CD4 of 8% (2.0%-15%); 92.5% were started on an NNRTI; median duration of follow-up was 2.9 (1.4-4.6) years. Loss-to-follow-up and death rates were 4.2 (3.7-4.8) and 2.1 (1.7-2.5) per 100 person-years, respectively. At 36 months, median CD4 was 26% (21%-31%); 81% of those with viral load (n = 302) were <400 copies per milliliter. Children who reached CD4 ≥25% within 5 years were more likely to be females (HR: 1.4; 1.2-1.7), start before 18 months old (HR: 3.8; 2.4-6.2), lack a history of monotherapy/dual therapy (HR: 1.7; 1.4-2.5), and have a higher baseline CD4 (per 10% increase: HR: 2; 1.9-2.2).

CONCLUSIONS

These data underscore the need for early diagnosis and cART initiation to preserve immune function.

A chewable pediatric fixed-dose combination tablet of stavudine, lamivudine, and nevirapine: pharmacokinetics and safety compared with the individual liquid formulations in human immunodeficiency virus-infected children in Thailand

BACKGROUND

Pediatric fixed-dose combinations (FDCs) are needed to facilitate antiretroviral therapy in children. We evaluated the relative bioavailability, safety, and therapeutic adequacy of a novel chewable pediatric FDC tablet of stavudine (7 mg), lamivudine (30 mg), and nevirapine (50 mg), referred to as GPO-VIR S7, and compared it with the individual original brand-name liquid formulations in human immunodeficiency virus-infected Thai children.

METHODS

The International Maternal Pediatric Adolescent AIDS Clinical Trials group (IMPAACT) P1056 study was a phase I/II, 2-arm, randomized, open-label, multidose pharmacokinetic cross-over study. Children ≥6 to ≤30 kg receiving nevirapine-based HAART for at least 4 weeks were randomized to receive GPO-VIR S7 chewable tablets or the equivalent liquid formulations. Children were stratified by weight and dosing was weight-based. Intensive 12-hour blood sampling was performed on day 28, and subjects then crossed-over to the alternate formulation at equal doses with identical 12-hour sampling on day 56. Pharmacokinetic indices were determined by noncompartmental analysis.

RESULTS

Thirty-four children completed the study. While taking Government Pharmaceutical Organization (GPO)-VIR S7 the geometric mean (90% CI) area under the curve was 1.54 μg·hr/mL (1.42-1.67) for stavudine, 6.39 (5.82-7.00) for lamivudine, and 74.06 (65.62-83.60) for nevirapine. Nevirapine drug exposure for GPO-VIR S7 was therapeutically adequate. Geometric mean area under the curve ratios (90% CI) of GPO-VIR S7/liquid formulation for stavudine, lamivudine, and nevirapine were 0.97 (0.92-1.02), 1.41 (1.30-1.53), and 1.08 (1.04-1.13), respectively. No serious drug-related toxicity was reported.

CONCLUSIONS

The chewable FDC was safe and provided therapeutically adequate plasma drug exposures in human immunodeficiency virus-infected children. Substituting the FDC for liquid formulations can simplify antiretroviral therapy.