The use of recombinant CD4-IgG2 in pediatric human immunodeficiency virus type 1 (HIV-1) infection was evaluated by single and multidose intravenous infusions in 18 children in a phase 1/2 study. The study drug was well tolerated, and dose proportionality was observed in terms of area under time-concentration curve and peak serum concentration. Acute decreases of >0.7 log(10) copies/mL in serum HIV-1 RNA concentration were seen in 4 of the 6 children treated with 4 weekly 10 mg/kg doses. At 14 days after treatment, 3 children had sustained reductions in serum HIV-1 RNA; the other children had rebounded to baseline levels or above. By 28 days after therapy, the peak HIV-1 cellular infectious units was reduced in all 6 children, including the 2 who had experienced an earlier transient increase in values. Thus, recombinant CD4-IgG2 treatment of HIV-1-infected children appears to be well tolerated and capable of reducing HIV-1 burden.

Children represent a significant proportion of the global tuberculosis (TB) burden, and may be disproportionately more affected by its most severe clinical manifestations. Currently available treatments for pediatric drug-susceptible (DS) and drug-resistant (DR) TB, albeit generally effective, are hampered by high pill burden, long duration of treatment, coexistent toxicities, and an overall lack of suitable, child-friendly formulations. The complex and burdensome nature of administering the existing regimens to treat DS TB also contributes to the rise of DR TB strains. Despite the availability and use of these therapies for decades, a dearth of dosing evidence in children underscores the importance of sustained efforts for TB drug development to better meet the treatment needs of children with TB. Several new TB drugs and regimens with promising activity against both DS and DR TB strains have recently entered clinical development and are in various phases of clinical evaluation in adults or have received marketing authorization for adults. However, initiation of clinical trials to evaluate these drugs in children is often deferred, pending the availability of complete safety and efficacy data in adults or after drug approval. This document summarizes consensus statements from an international panel of childhood TB opinion leaders which support the initiation of evaluation of new TB drugs and regimens in children at earlier phases of the TB Drug development cycle.

Objectives To determine safety, efficacy and genotypic-specific dose requirements of EFV in children aged 3 – < 36 months of age with HIV infection with or without TB co-infection. Design IMPAACT P1070 was a 24 week prospective cohort trial of EFV (as open capsules) plus two nucleoside reverse transcriptase inhibitors in children with HIV infection 3–<36 months without tuberculosis (Cohort 1). Methods CYP2B6 G516T genotype was determined and intensive PK’s were performed at week 2. EFV dose was adjusted if outside the target area under the curve (AUC) 35–180 mcg*hr/mL. PK and CYP2B6 G516T genotype data were used to model EFV exposures based on FDA-approved doses. Results Forty-seven participants, median age 19 months, initiated the study regimen with 24 weeks median follow up; 38 516GG/GT and 9 516TT genotypes. Initially, median EFV AUC was higher in 516TT versus 516GG/GT (median 490 vs 107 p =0.0001) with all 516TT above AUC target. Following an amendment that reduced the 516TT EFV dose by 75%, PK modeling predicted that 83% of participants met the AUC target (31/38 516GG/GT, 8/9 516TT). In contrast, modeling using P1070 data predicted that FDA-approved doses would produce sub-therapeutic AUCs in almost one third of participants with 516GG/GT and excessive AUCs in >50% with 516TT genotypes. Conclusion CYP2B6 G516T genotype strongly influences EFV exposures in this age group. Genotype-directed dosing yields therapeutic EFV concentrations and appears to out-perform other dosing approaches.

Infants born to human immunodeficiency virus type 1 (HIV-1)-infected mothers were immunized at birth and at ages 4, 12, and 20 weeks with low-, medium-, or high-dose recombinant gp120 vaccine with MF59 adjuvant (HIV-1(SF-2); n=52) or with MF59 alone as a placebo (n=9). An accelerated schedule (birth and ages 2, 8, and 20 weeks) was used for an additional 10 infants receiving the defined optimal dose and for 3 infants receiving placebo. At 24 weeks, anti-gp120 ELISA titers were greater for vaccine-immunized than for placebo-immunized infants on both schedules, and 87% of vaccinees had a vaccine-induced antibody response. At 12 weeks, antibody titers of infants on the accelerated vaccine schedule exceeded those of infants receiving placebo (4949 vs. 551; P=.01), and 63% of the vaccinees met the response criteria. Thus, an accelerated schedule of gp120 vaccinations generated an antibody response to HIV-1 envelope distinct from transplacental maternal antibody by age 12 weeks. These results provide support for further studies of vaccine strategies to prevent mother-to-infant HIV-1 transmission.

Summary Background Raltegravir is an integrase inhibitor approved for use in adults and children with HIV-1 infection, but there are no data on the long-term use of this medication in children. We aimed to assess the long-term safety, tolerability, pharmacokinetics, and efficacy of multiple raltegravir formulations in children aged 4 weeks to 18 years with HIV-1 infection. Methods In this phase 1/2 open-label multicentre trial (IMPAACT P1066), done in 43 IMPAACT network sites in the USA, South Africa, Brazil, Botswana, and Argentina, eligible participants were children aged 4 weeks to 18 years with HIV-1 infection who had previously received antiretroviral therapy (ART), had HIV-1 RNA higher than 1000 copies per mL, and no exposure to integrase inhibitors. Participants were separated into five age groups and enrolled in six cohorts. Three formulations of open-label raltegravir—adult tablets, chewable tablets, and granules for oral suspension—were added to individualised optimised background therapy, according to the age and weight of participants. The primary outcome at 48 weeks has been previously reported. In the 240-week follow-up, outcomes of interest included graded clinical and laboratory safety of raltegravir formulations during the study and virological efficacy (with virological success defined as HIV-1 RNA reduction of >1 log10 from baseline or HIV-1 RNA <400 copies per mL) at week 240. The primary analysis group for safety and efficacy comprised patients treated only with the final selected dose of raltegravir. This trial is registered with ClinicalTrials.gov, number . Findings Between August, 2007, and December, 2012, 220 patients were assessed for eligibility, and 153 were enrolled and treated. Of these patients, 122 received only the final selected dose of raltegravir (63 received adult tablets, 33 chewable tablets, and 26 oral granules), and one was not treated. There were few serious clinical or laboratory safety events noted, with two patients having a drug-related adverse event (skin rash), which led one patient to discontinue the study treatment. The addition of raltegravir to an individually optimised ART regimen resulted in virological success at week 240 in 19 (44·2%, 95% CI 29·1–60·1) of 43 patients receiving 400 mg tablets, 24 (77·4%, 58·9–90·4) of 31 patients receiving the chewable tablets, and 13 (86·7%, 59·5–98·3) of 15 patients receiving oral granules. Among patients with virological failure, raltegravir resistance was noted in 19 (38%) of 50 patients who had virological rebound after initial suppression and had samples at virological failure available for testing. Interpretation Our study suggests that raltegravir can be used for the treatment of HIV-1 infection in children as young as 4 weeks, with the expectation of long-term safety and efficacy, but should be used with caution among older children who had previous extensive antiretroviral therapy. Funding National Institute of Allergy and Infectious Diseases, National Institute of Child Health and Human Development, Nation...

The use of therapeutic proteins, such as Ig-based fusion proteins, is assuming an important place in medicine. 1,2 Because of the IgG Fc region of these proteins, there is a possibility that interactions with Fc receptors may interfere with dose-dependent therapeutics. 3 PRO 542 (CD4-IgG 2) is a tetravalent fusion protein designed to prevent the attachment of the virus through its glycoprotein 120 to the CD4 molecule on monocytes/macrophages and T cells. 4, 5 Our first study of PRO 542 in HIV-1-infected children documented that it was a safe therapeutic; exhibited linear dose-concentration pharmacokinetic behavior in 0.2, 1.0, 5.0, and 10.0 mg/kg studies; and possessed antiviral properties as assessed by plasma HIV-1-RNA

Objective To describe the pharmacokinetics of atazanavir (ATV) and ritonavir-boosted ATV/r in children ages 91 days to 21 years. Design Phase I/II, open label, multicenter study of once daily ATV and ATV/r as part of combination antiretroviral treatment in HIV-infected treatment experienced and naïve children. Setting Sites in the United States and South Africa. Subjects 195 children enrolled; 172 had evaluable ATV pharmacokinetics on day seven. Intervention Children were entered in age, dose and formulation (powder or capsule) cohorts. Intensive pharmacokinetic sampling occurred seven days after starting ATV. ATV doses were increased or decreased if the 24-hour area under the concentration time curves (AUC0–24hr) were <30 or >90 mcg*hr/mL, respectively. Main outcomes Cohorts satisfied protocol-defined pharmacokinetic criteria if the median ATV AUC0–24hr ≤60 mcg*hr/mL, and AUC0–24hr and ATV concentrations 24 hours post-dose (C24) were >30 mcg*hr/mL and ≥60 ng/mL, respectively, in ≥ 80% of children, with no individual AUC0–24hr <15 mcg*hr/mL. Results Unboosted ATV capsules satisfied pharmacokinetic criteria at a dose of 520 mg/m2 for those >2 to ≤ 13 years and 620 mg/m2 for those >13 to ≤ 21 years. ATV/r capsules satisfied criteria at a dose of 205 mg/m2 for those >2 to ≤ 21 years. ATV/r powder satisfied criteria at a dose of 310 mg/m2 for those >2 to ≤ 13 years, but pharmacokinetics in those ≤ 2 years were highly variable. Conclusions Body surface area-determined doses of ATV capsules and ATV/r powder and capsules provide ATV exposures in children >2 years that approximate values in adults receiving ATV/r.

Background: CYP2B6 516 genotype-directed dosing improves efavirenz (EFV) exposures in HIV-infected children younger than 36 months, but such data are lacking in those with tuberculosis (TB) coinfection. Methods: Phase I, 24-week safety and pharmacokinetic (PK) study of EFV in HIV-infected children aged 3 to <36 months, with or without TB. CYP2B6 516 genotype classified children into extensive metabolizers (516 TT/GT) and poor metabolizers [(PMs), 516 TT]. EFV doses were 25%–33% higher in children with HIV/TB coinfection targeting EFV area under the curve (AUC) 35–180 μg × h/mL, with individual dose adjustment as necessary. Safety and virologic evaluations were performed every 4–8 weeks. Results: Fourteen children from 2 African countries and India with HIV/TB enrolled, with 11 aged 3 to <24 months and 3 aged 24–36 months, 12 extensive metabolizers and 2 PMs. Median (Q1, Q3) EFV AUC was 92.87 (40.95, 160.81) μg × h/mL in 8/9 evaluable children aged 3 to <24 months and 319.05 (172.56, 360.48) μg × h/mL in children aged 24–36 months. AUC targets were met in 6/8 and 2/5 of the younger and older age groups, respectively. EFV clearance was reduced in PM's and older children. Pharmacokinetic modeling predicted adequate EFV concentrations if children younger than 24 months received TB-uninfected dosing. All 9 completing 24 weeks achieved viral suppression. Five/14 discontinued treatment early: 1 neutropenia, 3 nonadherence, and 1 with excessive EFV AUC. Conclusions: Genotype-directed dosing safely achieved therapeutic EFV concentrations and virologic suppression in HIV/TB-coinfected children younger than 24 months, but further study is needed to confirm appropriate dosing in those aged 24–36 months. This approach is most important for young children and currently a critical unmet need in TB-endemic countries.