Pharmacokinetics and 48-Week Safety and Efficacy of Raltegravir for Oral Suspension in Human Immunodeficiency Virus Type-1-Infected Children 4 Weeks to 2 Years of Age.

BACKGROUND: IMPAACT P1066 is a Phase I/II open-label multicenter trial to evaluate safety, tolerability, pharmacokinetics (PK), and efficacy of multiple raltegravir (RAL) formulations in human immunodeficiency virus (HIV)-infected youth. METHODS: Dose selection of the oral suspension formulation for each cohort (IV: 6 months to <2 years and V: 4 weeks to <6 months) was based on review of short-term safety (4 weeks) and intensive PK evaluation. Safety data through Weeks 24 and 48 and Grade ≥3 or serious adverse events (AEs) were assessed. The primary virologic endpoint was achieving HIV RNA <400 copies/mL or ≥1 log10 reduction from baseline at Week 24 (Success). For Cohort IV, optimized background therapy (OBT) could have been initiated with RAL either at study entry or after intensive PK sampling was completed at Day 5-12. An OBT was started when RAL was initiated for Cohort V subjects because they were not permitted to have received direct antiretroviral therapy before enrollment. RESULTS: Total accrual was 27 subjects in these 2 cohorts, including 1 subject who was enrolled but never started study drug (excluded from the analyses). The targeted PK parameters (area under the curve [AUC]0-12hr and C12hr) were achieved for each cohort allowing for dose selection. Through Week 48, there were 10 subjects with Grade 3+ AEs. Two were judged related to study drug. There was 1 discontinuation due to an AE of skin rash, 1 event of immune reconstitution syndrome, and no drug-related deaths. At Week 48, for Cohorts IV and V, 87.5% of subjects achieved virologic success and 45.5% had HIV RNA <50 copies/mL. At Week 48, gains in CD4 cells of 527.6 cells/mm(3) and 7.3% were observed. CONCLUSIONS: A total of 6 mg/kg per dose twice daily of RAL for oral suspension was well tolerated and showed favorable virologic and immunologic responses.

Raltegravir pharmacokinetics in neonates following maternal dosing.

: International Maternal Pediatric Adolescent AIDS Clinical Trials P1097 was a multicenter trial to determine washout pharmacokinetics and safety of in utero/intrapartum exposure to raltegravir in infants born to HIV-infected pregnant women receiving raltegravir-based antiretroviral therapy. Twenty-two mother-infant pairs were enrolled; evaluable pharmacokinetic data were available from 19 mother-infant pairs. Raltegravir readily crossed the placenta, with a median cord blood/maternal delivery plasma raltegravir concentration ratio of 1.48 (range, 0.32-4.33). Raltegravir elimination was highly variable and extremely prolonged in some infants; [median t1/2 26.6 (range, 9.3-184) hours]. Prolonged raltegravir elimination likely reflects low neonatal UGT1A1 enzyme activity and enterohepatic recirculation. Excessive raltegravir concentrations must be avoided in the neonate because raltegravir at high plasma concentrations may increase the risk of bilirubin neurotoxicity. Subtherapeutic concentrations, which could lead to inadequate viral suppression and development of raltegravir resistance, must also be avoided. Two ongoing International Maternal Pediatric Adolescent AIDS Clinical Trials studies are further investigating the pharmacology of raltegravir in neonates.

Pharmacokinetics, safety, and 48-week efficacy of oral raltegravir in HIV-1-infected children aged 2 through 18 years.

BACKGROUND: IMPAACT P1066 is a phase I/II open-label multicenter trial to evaluate pharmacokinetics, safety, tolerability, and efficacy of multiple raltegravir formulations in human immunodeficiency virus (HIV)-infected youth. METHODS: Dose selection for each cohort (I: 12 to <19 years; II: 6 to <12 years; and III: 2 to <6 years) was based on review of short-term safety (4 weeks) and intensive pharmacokinetic evaluation. Safety data through weeks 24 and 48, and grade ≥ 3 or serious adverse events (AEs) were assessed. The primary virologic endpoint was achieving HIV RNA <400 copies/mL or ≥ 1 log10 reduction between baseline and week 24. RESULTS: The targeted pharmacokinetic parameters (AUC0-12h and C12h) were achieved for each cohort, allowing dose selection for 2 formulations. Of 96 final dose subjects, there were 15 subjects with grade 3 or higher clinical AEs (1 subject with drug-related [DR] psychomotor hyperactivity and insomnia); 16 subjects with grade 3 or higher laboratory AEs (1 with DR transaminase elevation); 14 subjects with serious clinical AEs (1 with DR rash); and 1 subjects with serious laboratory AEs (1 with DR transaminase increased). There were no discontinuations due to AEs and no DR deaths. Favorable virologic responses at week 48 were observed in 79.1% of patients, with a mean CD4 increase of 156 cells/µL (4.6%). CONCLUSIONS: Raltegravir as a film-coated tablet 400 mg twice daily (6 to <19 years, and ≥ 25 kg) and chewable tablet 6 mg/kg (maximum dose 300 mg) twice daily (2 to <12 years) was well tolerated and showed favorable virologic and immunologic responses. CLINICAL TRIALS REGISTRATION: NCT00485264.

Early time-limited antiretroviral therapy versus deferred therapy in South African infants infected with HIV: results from the children with HIV early antiretroviral (CHER) randomised trial.

BACKGROUND: Interim results from the children with HIV early antiretroviral (CHER) trial showed that early antiretroviral therapy (ART) was life-saving for infants infected with HIV. In view of the few treatment options and the potential toxicity associated with lifelong ART, in the CHER trial we compared early time-limited ART with deferred ART. METHODS: CHER was an open-label randomised controlled trial of HIV-infected asymptomatic infants younger than 12 weeks in two South African trial sites with a percentage of CD4-positive T lymphocytes (CD4%) of 25% or higher. 377 infants were randomly allocated to one of three groups: deferred ART (ART-Def), immediate ART for 40 weeks (ART-40W), or immediate ART for 96 weeks (ART-96W), with subsequent treatment interruption. The randomisation schedule was stratified by clinical site with permuted blocks of random sizes to balance the numbers of infants allocated to each group. Criteria for ART initiation in the ART-Def group and re-initiation after interruption in the other groups were CD4% less than 25% in infancy; otherwise, the criteria were CD4% less than 20% or Centers for Disease Control and Prevention severe stage B or stage C disease. Combination therapy of lopinavir-ritonavir, zidovudine, and lamivudine was the first-line treatment regimen at ART initiation and re-initiation. The primary endpoint was time to failure of first-line ART (immunological, clinical, or virological) or death. Comparisons were done by intention-to-treat analysis, with use of time-to-event methods. This trial is registered with ClinicalTrials.gov, number NCT00102960. FINDINGS: 377 infants were enrolled, with a median age of 7·4 weeks, CD4% of 35%, and HIV RNA log 5·7 copies per mL. Median follow-up was 4·8 years; 34 infants (9%) were lost to follow-up. Median time to ART initiation in the ART-Def group was 20 weeks (IQR 16-25). Time to restarting of ART after interruption was 33 weeks (26-45) in ART-40W and 70 weeks (35-109) in ART-96W; at the end of the trial, 19% of patients in ART-40W and 32% of patients in ART-96W remained off ART. Proportions of follow-up time spent on ART were 81% in the ART-Def group, 70% in the ART-40W group, and 69% in the ART-96W group. 48 (38%) of 125 children in the ART-Def group, 32 (25%) of 126 in the ART-40W group, and 26 (21%) of 126 in the ART-96W group reached the primary endpoint. The hazard ratio, relative to ART-Def, was 0·59 (95% CI 0·38-0·93, p=0·02) for ART-40W and 0·47 (0·27-0·76, p=0·002) for ART-96W. Three children in ART-Def, three in ART-40W, and one in ART-96W switched to second-line ART. INTERPRETATION: Early time-limited ART had better clinical and immunological outcomes than deferred ART, with no evidence of excess disease progression during subsequent treatment interruption and less overall ART exposure than deferred ART. Longer time on primary ART permits longer subsequent interruption, with marginally better outcomes. FUNDING: US National Institutes of Health.

High proportions of regulatory B and T cells are associated with decreased cellular responses to pH1N1 influenza vaccine in HIV-infected children and youth (IMPAACT P1088).

HIV-infected individuals have poor responses to inactivated influenza vaccines. To evaluate the potential role of regulatory T (Treg) and B cells (Breg), we analyzed their correlation with humoral and cell-mediated immune (CMI) responses to pandemic influenza (pH1N1) monovalent vaccine in HIV-infected children and youth. Seventy-four HIV-infected, 4- to 25-y old participants in a 2-dose pH1N1 vaccine study had circulating and pH1N1-stimulated Treg and Breg measured by flow cytometry at baseline, post-dose 1 and post-dose 2. Concomitantly, CMI was measured by ELISPOT and flow cytometry; and antibodies by hemagglutination inhibition (HAI). At baseline, most of the participants had pH1N1-specific IFNγ ELISPOT responses, whose magnitude positively correlated with the baseline pH1N1, but not with seasonal H1N1 HAI titers. pH1N1-specific IFNγ ELISPOT responses did not change post-dose 1 and significantly decreased post-dose 2. In contrast, circulating CD4+CD25+% and CD4+FOXP3+% Treg increased after vaccination. The decrease in IFNγ ELISPOT results was marginally associated with higher pH1N1-specific CD19+FOXP3+ and CD4+TGFß+% Breg and Treg, respectively. In contrast, increases in HAI titers post-dose 1 were associated with significantly higher circulating CD19+CD25+% post-dose 1, whereas increases in IFNγ ELISPOT results post-dose 1 were associated with higher circulating CD4+/C8+CD25+FOXP3+%. In conclusion, in HIV-infected children and youth, influenza-specific Treg and Breg may contribute to poor responses to vaccination. However, robust humoral and CMI responses to vaccination may result in increased circulating Treg and/or Breg, establishing a feed-back mechanism.

Safety and immunogenicity of 2009 pH1N1 vaccination in HIV-infected pregnant women.

BACKGROUND: Pregnant women infected with human immunodeficiency virus (HIV) may have particular vulnerability to 2009 pandemic H1N1 influenza (pH1N1) infection. The safety and immunogenicity of pH1N1 vaccination in HIV-infected pregnant women are unknown. METHODS: HIV-infected women 18-39 years of age and 14-34 weeks' gestation on antiretroviral therapy received two 30-µg doses of unadjuvanted, inactivated pH1N1 vaccine 21 days apart. Hemagglutination inhibition titers were measured at entry, 21 days after dose 1, and 10 and 21 days after dose 2, and, in mothers and infants, at delivery and 3 and 6 months postdelivery. RESULTS: No severe vaccine-related adverse events were observed among 127 subjects. At entry, 21% had seroprotective (≥1:40) titers. Seroprotection and seroresponse (≥4-fold rise) occurred in 73% and 66% after dose 1 and 80% and 72% after dose 2, respectively. Of women lacking seroprotection at entry, 66% attained seroprotection after dose 1 and 75% after dose 2. Seroprotective titers were present in 67% of mothers and 65% of infants at delivery (median 66 days after dose 2), 60% of mothers and 26% of infants at 3 months postdelivery, and 59% of mothers and 12% of infants at 6 months postdelivery. CONCLUSIONS: Two 30-µg doses were moderately immunogenic in HIV-infected pregnant women. No concerning vaccine-related safety signals were observed. Seroprotection persisted in most women postpartum. Efficient transplacental antibody transfer occurred, but seroprotection in infants waned rapidly. Vaccination to protect HIV-infected pregnant women and their newborns from new influenza strains is feasible, but more immunogenic platforms should be evaluated. Clinical Trials Registration. NCT00992017.

Safety and immunogenicity of 2009 pandemic H1N1 influenza vaccination in perinatally HIV-1-infected children, adolescents, and young adults.

BACKGROUND: The safety and immunogenicity of high-dose pandemic H1N1 (pH1N1) vaccination in perinatally human immunodeficiency virus type 1 (HIV-1)-infected children, adolescents, and young adults are unknown. METHODS: Two 30-µg doses of 2009 Novartis pH1N1 monovalent vaccine (Fluvirin) were administered 21-28 days apart to perinatally HIV-1-infected children, adolescents, and young adults. Antibodies were measured by hemagglutination inhibition (HAI) assay at baseline, 21-28 days after first vaccination, 7-13 days after the second vaccination, and 7 months after the first vaccination. RESULTS: Among the 155 participants, 54 were aged 4-8 years, 51 were aged 9-17 years, and 50 were aged 18-24 years. After 2 doses of Fluvirin, seroresponse (≥ 4-fold rise in HAI titers) was demonstrated in 79.6%, 84.8%, and 83% of participants in the aforementioned age groups, respectively, and seroprotection (HAI titers ≥ 40) was shown in 79.6%, 82.6%, and 85.1%, respectively. Of those lacking seroresponse (n = 43) or seroprotection (n = 37) after the first vaccination, 46.5% and 40.5% achieved seroresponse or seroprotection, respectively, after the second vaccination. Among participants who lacked seroprotection at entry, a "complete response" (both seroresponse and seroprotection) after first vaccination was associated with higher baseline log(10) HAI titer and non-Hispanic ethnicity. No serious vaccine-related events occurred. CONCLUSION: Two doses of double-strength pH1N1 vaccine are safe and immunogenic and may provide improved protection against influenza in perinatally HIV-1-infected children and youth. CLINICAL TRIALS REGISTRATION: NCT00992836.

Safety and immunogenicity of a quadrivalent human papillomavirus (types 6, 11, 16, and 18) vaccine in HIV-infected children 7 to 12 years old.

BACKGROUND: Quadrivalent human papillomavirus vaccine (QHPV) is > 95% effective in preventing infection with vaccine-type human papillomavirus. The safety and immunogenicity of QHPV are unknown in HIV-infected children. METHODS: HIV-infected children (N = 126)-age > 7 to < 12 years, with a CD4% ≥ 15-and on stable antiretroviral therapy if CD4% was < 25-were blindly assigned to receive a dose of QHPV or placebo (3:1 ratio) at 0, 8, and 24 weeks. Adverse events were evaluated after each dose. Serum antibody against QHPV antigens was measured by a competitive Luminex immunoassay 1 month after the third QHPV dose. RESULTS: The safety profile of QHPV was similar in the 2 study arms and to that previously reported for QHPV recipients. QHPV did not alter the CD4% or plasma HIV RNA. Seroconversion to all 4 antigens occurred in > 96% of QHPV recipients and in no placebo recipients. Geometric mean titer was > 27 to 262 times greater than the seropositivity cutoff value, depending on the antigen, but was 30%-50% lower against types 6 and 18 than those of age-similar historical controls. CONCLUSIONS: QHPV was safe and immunogenic in this cohort of HIV-infected children. Efficacy trials are warranted.

Guidelines for the Prevention and Treatment of Opportunistic Infections among HIV-exposed and HIV-infected children: recommendations from CDC, the National Institutes of Health, the HIV Medicine Association of the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the American Academy of Pediatrics.

This report updates and combines into one document earlier versions of guidelines for preventing and treating opportunistic infections (OIs) among HIV-exposed and HIV-infected children, last published in 2002 and 2004, respectively. These guidelines are intended for use by clinicians and other health-care workers providing medical care for HIV-exposed and HIV-infected children in the United States. The guidelines discuss opportunistic pathogens that occur in the United States and one that might be acquired during international travel (i.e., malaria). Topic areas covered for each OI include a brief description of the epidemiology, clinical presentation, and diagnosis of the OI in children; prevention of exposure; prevention of disease by chemoprophylaxis and/or vaccination; discontinuation of primary prophylaxis after immune reconstitution; treatment of disease; monitoring for adverse effects during treatment; management of treatment failure; prevention of disease recurrence; and discontinuation of secondary prophylaxis after immune reconstitution. A separate document about preventing and treating of OIs among HIV-infected adults and postpubertal adolescents (Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents) was prepared by a working group of adult HIV and infectious disease specialists. The guidelines were developed by a panel of specialists in pediatric HIV infection and infectious diseases (the Pediatric Opportunistic Infections Working Group) from the U.S. government and academic institutions. For each OI, a pediatric specialist with content-matter expertise reviewed the literature for new information since the last guidelines were published; they then proposed revised recommendations at a meeting at the National Institutes of Health (NIH) in June 2007. After these presentations and discussions, the guidelines underwent further revision, with review and approval by the Working Group, and final endorsement by NIH, CDC, the HIV Medicine Association (HIVMA) of the Infectious Diseases Society of America (IDSA), the Pediatric Infectious Disease Society (PIDS), and the American Academy of Pediatrics (AAP). The recommendations are rated by a letter that indicates the strength of the recommendation and a Roman numeral that indicates the quality of the evidence supporting the recommendation so readers can ascertain how best to apply the recommendations in their practice environments. An important mode of acquisition of OIs, as well as HIV infection among children, is from their infected mother; HIV-infected women coinfected with opportunistic pathogens might be more likely than women without HIV infection to transmit these infections to their infants. In addition, HIV-infected women or HIV-infected family members coinfected with certain opportunistic pathogens might be more likely to transmit these infections horizontally to their children, resulting in increased likelihood of primary acquisition of such infections in the young child. Therefore, infections with opportunistic pathogens might affect not just HIV-infected infants but also HIV-exposed but uninfected infants who become infected by the pathogen because of transmission from HIV-infected mothers or family members with coinfections. These guidelines for treating OIs in children therefore consider treatment of infections among all children, both HIV-infected and uninfected, born to HIV-infected women. Additionally, HIV infection is increasingly seen among adolescents with perinatal infection now surviving into their teens and among youth with behaviorally acquired HIV infection. Although guidelines for postpubertal adolescents can be found in the adult OI guidelines, drug pharmacokinetics and response to treatment may differ for younger prepubertal or pubertal adolescents. Therefore, these guidelines also apply to treatment of HIV-infected youth who have not yet completed pubertal development. Major changes in the guidelines include 1) greater emphasis on the importance of antiretroviral therapy for preventing and treating OIs, especially those OIs for which no specific therapy exists; 2) information about the diagnosis and management of immune reconstitution inflammatory syndromes; 3) information about managing antiretroviral therapy in children with OIs, including potential drug--drug interactions; 4) new guidance on diagnosing of HIV infection and presumptively excluding HIV infection in infants that affect the need for initiation of prophylaxis to prevent Pneumocystis jirovecii pneumonia (PCP) in neonates; 5) updated immunization recommendations for HIV-exposed and HIV-infected children, including hepatitis A, human papillomavirus, meningococcal, and rotavirus vaccines; 6) addition of sections on aspergillosis; bartonella; human herpes virus-6, -7, and -8; malaria; and progressive multifocal leukodystrophy (PML); and 7) new recommendations on discontinuation of OI prophylaxis after immune reconstitution in children. The report includes six tables pertinent to preventing and treating OIs in children and two figures describing immunization recommendations for children aged 0--6 years and 7--18 years. Because treatment of OIs is an evolving science, and availability of new agents or clinical data on existing agents might change therapeutic options and preferences, these recommendations will be periodically updated and will be available at http://AIDSInfo.nih.gov.

Endocrine abnormalities and impaired growth in human immunodeficiency virus-infected children.

OBJECTIVES: Identify endocrine differences between human immunodeficiency virus- (HIV) infected versus uninfected children and evaluate associations of growth and body composition with endocrine measures. STUDY DESIGN: Nested case-control study in 21 HIV-infected and 46 age- and sex-matched uninfected children in the Women and Infant Transmission Study. Plasma specimens from children between 2.5 to 7.0 years of age, taken during 3-4 visits, were tested for insulin-like growth factor binding protein-3 (IGFBP-3), cortisol, dehydroepiandrosterone (DHEA), growth hormone and thyroid studies. Longitudinal mixed and generalized estimating equation models compared group means and examined effects of endocrine measures on growth and body composition, respectively. RESULTS: HIV-infected children had lower IGFBP-3 than uninfected children (1.96 +/- 0.09 mg/L versus 2.34 +/- 0.06 mg/L, P < 0.001). In infected but not in uninfected children, IGFBP-3 values and DHEA:cortisol ratios were associated with weight- and body mass index-for-age z scores ([WAZ] P = 0.019, <.001 respectively, and [BMZ] P = 0.029, 0.038). DHEA concentration was associated with height-for-age z score (P = 0.049). CONCLUSIONS: In these HIV-infected children compared with their uninfected counterparts, IGFBP-3 concentration was different between groups. Infected children had multiple endocrine associations with growth and body composition not found in their uninfected peers. We hypothesize that in HIV-infected children, growth hormone resistance and shunting of precursors from adrenal androgen to cortisol production contributes to altered body composition and stunting.

Effect of perinatal antiretroviral drug exposure on hematologic values in HIV-uninfected children: An analysis of the women and infants transmission study.

BACKGROUND: With the increasing use of antiretroviral (ARV) drugs to prevent mother-to-child transmission of human immunodeficiency virus (HIV), large numbers of infants are exposed, with possible consequent toxicity. METHODS: Hematologic values in 1820 uninfected HIV- and ARV-exposed children were compared with those in 351 ARV-unexposed children from the Women and Infants Transmission Study. Hemoglobin concentrations and platelet, neutrophil, lymphocyte, and CD4+ and CD8+ cell counts were analyzed at birth and ages 2, 6, 12, 18, and 24 months. Multivariate analysis was conducted age 0-2 and 6-24 months, with adjustment for multiple cofactors. RESULTS: Hemoglobin concentrations and neutrophil, lymphocyte, and CD4+ cell counts were significantly lower at age 0-2 months in infants exposed to ARV drugs than in those who were not. At 6-24 months, differences in hemoglobin concentrations and neutrophil counts were no longer significant, whereas differences in platelet, lymphocyte, and CD4+ cell counts persisted and CD8+ cell counts became significantly lower. In comparison with ARV monotherapy, combination therapy was associated with larger decreases in neutrophil, lymphocyte, and CD8+ cell counts at age 0-2 months but with only differences in CD8+ cell counts at age 6-24 months. Clinically significant abnormalities were rare and did not differ by exposure to ARV drugs. CONCLUSION: Infants exposed to ARV drugs have small but significant differences in several hematologic parameters for the first 24 months of life. These results indicate the need for long-term follow-up of uninfected infants with ARV exposure.

Predictors of immunologic long-term nonprogression in HIV-infected children: implications for initiating therapy.

BACKGROUND: Early markers that predict immunologic long-term nonprogression in infants with perinatally acquired HIV infection might assist in subsequent antiretroviral treatment decisions. OBJECTIVES: We sought to identify early markers of immunologic long-term HIV disease nonprogression. METHODS: We analyzed immunologic and virologic characteristics at 1 and 2 months of age in HIV-infected children who were enrolled in the Women and Infants Transmission Study and born before 1995, comparing immunologic long-term nonprogressors (ILTNPs; n = 10) with non-ILTNPs (n = 127). ILTNPs were children who survived to 8 years or older with CD4 percentages of 25% or greater and counts of 500 cells/mm 3 or more without receiving highly active antiretroviral therapy. Non-ILTNPs were defined as all other HIV-infected children. Receiver operating characteristic curve analysis was used to assess combined sensitivity and specificity for each of these characteristics and to determine potential threshold values to discriminate between ILTNPs and non-ILTNPs. RESULTS: Characteristics in the first 2 months of life associated with ILTNP status in univariate analysis included higher CD4 percentages, lower CD8 + percentages, lower CD8 + HLA-DR + percentages, and lower HIV-1 RNA PCR values. In receiver operating characteristic analysis CD8 + HLA-DR + percentage had the best combined sensitivity and specificity for discriminating between ILTNPs and non-ILTNPs. CD8 + HLA-DR + percentages of 5% or less predicted ILTNP status with 80% sensitivity and 80% specificity. In multivariate analysis CD8 + HLA-DR+ percentage of 5% or less remained a significant predictor of ILTNP status after adjusting for CD3 + CD4 + percentage and HIV-1 RNA PCR value (odds ratio, 15.4; 95% CI, 1.9-124.7). CONCLUSION: CD8 + HLA-DR + T-lymphocyte percentage of less than 5% at 1 to 2 months of age might be predictive for ILTNP status but should not be used at this time to make treatment-deferral decisions. Immune activation in HIV-infected infants might herald more disease progression. Further study of the use of this subpopulation in early infancy to predict ILTNP status is warranted.

Morbidity and mortality during the first two years of life among uninfected children born to human immunodeficiency virus type 1-infected women: the women and infants transmission study.

OBJECTIVE: We evaluated morbidity and mortality during the first 2 years of life among children born to human immunodeficiency virus-(HIV) type 1-infected women enrolled in the Women and Infants Transmission Study (WITS) during an 11-year period (1990-2001). DESIGN AND METHODS: As part of WITS, evaluations were performed at birth and at 1, 2, 4, 6, 9, 12, 18 and 24 months of age. Growth, hospitalization and the incidence of clinical disease were assessed regularly. RESULTS: Data regarding 1118 children born to HIV-infected women (955 HIV-uninfected children and 163 HIV-infected children) were analyzed. Fewer changes in the caretaker of the child and fewer in utero exposures to drugs, tobacco and alcohol occurred in the latter periods of the study (all P values for time trend analyses <0.01). The percentages of HIV-uninfected children with poor weight gain (44 of 767; 5.7%), short stature (32 of 703; 4.5%) and wasting (27 of 792; 3.4%) were higher than expected for the general population. Two or more changes in caretaker were associated with all growth deficiencies except wasting, and fetal exposure to tobacco was associated with height abnormalities. Anemia was common and was associated with receipt of zidovudine prophylaxis. Morbidity and mortality decreased during the study period. For the uninfected children, a decrease in class A events (Kaplan-Meier rates: group 1, 22.3%; group 2, 6.8%; group 3, 4.2%; P < 0.001) and class C events and death (Kaplan- Meier event rates: group 1, 2.0%; group 2, 1.7%; group 3, 0.2%; P = 0.062) during the first 2 years of life account for the differences in the curves over time. CONCLUSIONS: During an 11-year period, morbidity and mortality during the first 24 months of life decreased substantially for children born to HIV-infected women.

Immune parameters and morbidity in hard drug and human immunodeficiency virus-exposed but uninfected infants.

OBJECTIVE: To examine the association of maternal hard drug use (injection drugs, cocaine, and opiates) on lymphocyte subsets and clinical morbidity in uninfected infants who are born to human immunodeficiency virus-infected mothers who were enrolled in the Women and Infants Transmission Study (1990-2000). METHODS: Maternal hard drug use was identified by self-report and/or urine toxicology. Infant evaluations occurred at birth and at 1, 2, 4, 6, 9, 12, 18, and 24 months of age. RESULTS: A total of 401 (28%) of the 1436 uninfected infants were born to drug-using mothers. Maternal CD4 lymphocyte percentage and RNA at delivery were not significantly different between drug users and nonusers. Infants who were born to drug-using mothers had lower mean gestational age (37.8 vs 38.5 weeks) and birth weight (2.9 vs 3.1 kg). Infants with intrauterine drug exposure had lower CD4 lymphocyte percentage over the first 4 months of life after adjusting for covariates and higher natural killer lymphocyte percentage. When the analysis was stratified by time period of entry, the incidence of clinical events was not different between infants who were born to drug users versus nonusers. CONCLUSION: Maternal hard drug use is associated with immunologic changes in infants early in life, although these changes did not seem to be associated with increased risk of infections.

Mother-to-child transmission of HIV-1: strong association with certain maternal HLA-B alleles independent of viral load implicates innate immune mechanisms.

The transmission of HIV-1 from mother to child during pregnancy is unlike other types of HIV-1 transmission because the child shares major histocompatibility complex (MHC) genes with the mother during a time while the mother is induced to tolerate the paternally derived fetal MHC molecules, in part through natural killer (NK) recognition of MHC polymorphisms. The relevance of these immune mechanisms to HIV-1 transmission was assessed by determining the HLA-B alleles of mother and infant. Almost half (48%) of mothers who transmitted with low viral loads had HLA-B*1302, B*3501, B*3503, B*4402, or B*5001 alleles, compared with 8% of nontransmitting mothers (P=0.001). Conversely, 25% of mothers who did not transmit despite high viral loads had B*4901 and B*5301, vs. 5% of transmitting mothers (P=0.003), a pattern of allelic involvement distinct from that influencing HIV-1 infection outcome. The infant's HLA-B alleles did not appear associated with transmission risk. The HLA-B*4901 and B*5301 alleles that were protective in the mother both differed respectively from the otherwise identical susceptibility alleles, B*5001 and B*3501, by 5 amino acids encoding the ligand for the KIR3DL1 NK receptor. These results suggest that the probable molecular basis of the observed association involves definition of the maternal NK recognition repertoire by engagement of NK receptors with polymorphic ligands encoded by maternal HLA-B alleles, and that the placenta is the likely site of the effect that appears to protect against transmission of maternal HIV-1 through interrelating adaptive and innate immune recognition.

Long-term effects of protease-inhibitor-based combination therapy on CD4 T-cell recovery in HIV-1-infected children and adolescents.

BACKGROUND: There is limited evidence about longer-term effects of combination antiretroviral therapy that includes protease inhibitors (PIs) on the immunological status of HIV-1-infected children. Better understanding might help to resolve questions on when to initiate treatment. METHODS: The change in percentage of CD4-positive T lymphocytes (CD4%) was investigated in 1012 previously treated HIV-1-infected children (aged 0-17 years) who were enrolled in research clinics in the USA before 1996 and followed up to 2000. 702 started PI-based combination therapy. Data analyses ignored subsequent treatment changes. FINDINGS: Among the 1012 children, the median CD4% increased from 22% to 28% between 1996, when PIs were first prescribed, and 2000. For the 702 who started PI-based therapy, the mean CD4% increase after 3 years was largest among participants with the greatest immunosuppression (15.7%, 10.6%, 5.1%, and 2.0% for participants with CD4% before therapy of <5%, 5-14%, 15-24%, and >25%; p<0.0001). After adjustment for pre-PI CD4%, the mean increase was largest among the youngest participants (9.2%, 8.0%, and 4.3% for ages <5 years, 5-9 years, and >10 years; p=0.001). However, only a minority of significantly immunocompromised participants (33%, 26%, and 49% of those with pre-PI CD4% of <5%, 5-14%, or 15-24%) achieved CD4% values above 25%, whereas 84% of those with pre-PI values above 25% maintained such values. INTERPRETATION: Although PI-based therapy was associated with substantial improvements in CD4%, initiation before severe immunosuppression and at younger ages may be more effective for recovery or maintenance of normal CD4%. Randomised investigation of when to start combination therapy in children, particularly infants, is needed.

Forty-eight-week evaluation of lopinavir/ritonavir, a new protease inhibitor, in human immunodeficiency virus-infected children.

BACKGROUND: Lopinavir/ritonavir has demonstrated antiviral activity in the HIV-infected adult. SUBJECTS: The objective of this study was to investigate a liquid coformulation of lopinavir/ritonavir, in combination with reverse transcriptase inhibitors, in HIV-infected children. METHODS: One hundred antiretroviral (ARV)-naive and ARV-experienced, nonnucleoside reverse transcriptase inhibitor-naive children between 6 months and 12 years of age participated in this Phase I/II, open label, multicenter trial. Subjects initially received either 230/57.5 mg/m(2) or 300/75 mg/m(2) lopinavir/ritonavir twice daily; ARV-naive subjects also received stavudine and lamivudine, whereas ARV-experienced subjects also received nevirapine and one or two nucleoside reverse transcriptase inhibitors. Lopinavir/ritonavir pharmacokinetics, safety and efficacy were evaluated. RESULTS: All subjects were escalated to the 300/75 mg/m(2) twice daily dose based on results from an interim pharmacokinetic and safety evaluation. The pharmacokinetics of lopinavir did not appear to be dependent on age when dosing was based on body surface area but were decreased on coadministration with nevirapine. Overall 79% of subjects had HIV RNA levels <400 copies/ml at Week 48 (intent-to-treat: missing = failure). Mean increases in absolute and relative (percent) CD4 counts from baseline to Week 48 were observed in both ARV-naive subjects (404 cells/mm(3); 10.3%) and ARV-experienced subjects (284 cells/mm(3); 5.9%). Only one subject prematurely discontinued the study because of a study drug-related adverse event. CONCLUSIONS: The liquid coformulation of lopinavir/ritonavir demonstrated durable antiviral activity and was safe and well-tolerated after 48 weeks of treatment in HIV-infected children.

Combination antiretroviral strategies for the treatment of pregnant HIV-1-infected women and prevention of perinatal HIV-1 transmission.

CONTEXT: The Women and Infants Transmission Study is a prospective natural history study that has been enrolling HIV-1-infected pregnant women and their infants since 1989. OBJECTIVE: To evaluate the impact of different antiretroviral regimens on perinatal HIV-1 transmission at the population level. DESIGN: Prospective cohort study. Plasma HIV-1 RNA levels were serially measured in 1542 HIV-1-infected women with singleton live births between January 1990 and June 2000. MAIN OUTCOME MEASURE: HIV-1 status of the infant. RESULTS: HIV-1 transmission was 20.0% (95% confidence interval [CI], 16.1%-23.9%) for 396 women who not receiving prenatal antiretroviral therapy; 10.4% (95% CI, 8.2%-12.6%) for 710 receiving zidovudine monotherapy; 3.8% (95% CI, 1.1%-6.5%) for 186 receiving dual antiretroviral therapy with no or one highly active drug (Multi-ART); and 1.2% (95% CI, 0-2.5%) for 250 receiving highly active antiretroviral therapy (HAART). Transmission also varied by maternal delivery HIV RNA level: 1.0% for <400; 5.3% for 400 to 3499; 9.3% for 3500 to 9999; 14.7% for 10,000 to 29,999; and 23.4% for >30,000 copies/mL (p =.0001 for trend). The odds of transmission increased 2.4-fold (95% CI, 1.7-3.5) for every log10 increase in delivery viral load. In multivariate analyses adjusting for maternal viral load, duration of therapy, and other factors, the odds ratio for transmission for women receiving Multi-ART and HAART compared with those receiving ZDV monotherapy was 0.30 (95% CI, 0.09-1.02) and 0.27 (95% CI, 0.08-0.94), respectively. CONCLUSION: Levels of HIV-1 RNA at delivery and prenatal antiretroviral therapy were independently associated with transmission. The protective effect of therapy increased with the complexity and duration of the regimen. HAART was associated with the lowest rates of transmission.