Elbasvir/grazoprevir in children aged 3-18 years with chronic HCV genotype 1 or 4 infection: a pharmacokinetic modeling study

BACKGROUND

Approximately 3.5 million children and adolescents worldwide are chronically infected with HCV. This study uses pharmacokinetic modeling to identify pediatric doses of elbasvir/grazoprevir (EBR/GZR) that achieve plasma concentrations similar to those seen in adults receiving the approved fixed-dose combination regimen of EBR/GZR.

PATIENTS AND METHODS

We conducted a nonrandomized, single-arm, multicenter, open-label phase 2b trial in children and adolescents aged 3 to <18 years with chronic HCV genotype 1 or 4 infection (NCT03379506). Pharmacokinetic data were used to bridge efficacy and safety data from adults to children in a stepwise (oldest to youngest) manner. A total of 57 participants were enrolled: cohort 1 (aged 12 to <18 y), n=22; cohort 2 (aged 7 to <12 y), n=17; and cohort 3 (aged 3 to <7 y), n=18.

RESULTS

Steady-state plasma exposures were achieved by week 4 for EBR and GZR in all cohorts and daily dosing achieved geometric mean steady-state area under the concentration-time curve at 0-24 hours that fell within comparability bounds established for adults. All participants achieved sustained virologic response 12 weeks after completing treatment (ie, undetectable HCV RNA 12 wk following completion of treatment). Headache (n=4), fatigue (n=4), and nausea (n=2) were the most common treatment-related adverse events (all mild or moderate); no participant discontinued because of an adverse event.

CONCLUSIONS

Pediatric EBR/GZR pharmacokinetic models were successfully developed based on complex adult population pharmacokinetic models. At appropriate age-related doses, EBR/GZR is safe and effective in pediatric and adolescent participants with HCV infection.

Immunogenicity and safety of different schedules of the meningococcal ABCWY vaccine, with assessment of long-term antibody persistence and booster responses - results from two phase 2b randomized trials in adolescents

The meningococcal serogroup B (MenB) protein vaccine, 4CMenB, combined with MenA, MenC, MenW and MenY polysaccharide-protein conjugates for a pentavalent MenABCWY vaccine, can potentially protect against most causative agents of invasive meningococcal disease worldwide. Two phase 2b, randomized, multicenter studies were conducted (NCT02212457, NCT02946385) to assess the immunogenicity and safety of the MenABCWY vaccine as well as antibody persistence and response to a booster dose 2 years after the last vaccination, compared to 4CMenB vaccination. Participants (10 − 18 years), randomized (3:3:2:2:2:2), received the 4-component 4CMenB vaccine according to a 0–2 month (M) schedule or MenABCWY according to a 0–2, 0–6, 0-2-6, 0–1, or 0–11 M schedule. All participants received 5 injections (at M0, M1, M2, M6 and M12) with either the study vaccines or placebo/hepatitis A vaccine. Follow-on participants (4CMenB-0-2, MenABCWY-0-2, MenABCWY-0-6 and MenABCWY-0-2-6 groups) received one dose of either 4CMenB (4CMenB-0-2 group) or MenABCWY and newly enrolled, age-matched, meningococcal vaccine-naïve adolescents (randomized 1:1) received 2 doses (0–2 M) of either 4CMenB or MenABCWY. MenABCWY vaccination was immunogenic against MenB test strains. Non-inferiority for all 4 components of the 4CMenB vaccine could not be demonstrated for the 0–2 M schedule. Antibodies persisted up to 2 years post-MenABCWY vaccination and a booster dose induced an anamnestic response as higher titers were observed in follow-on participants compared to the first-dose response in vaccine-naïve participants. MenABCWY had a clinically-acceptable safety profile, not different from that of 4CMenB.

13-valent pneumococcal conjugate vaccine (PCV13) in preterm versus term infants

OBJECTIVES

This study evaluated the immune response and safety profile of 13-valent pneumococcal conjugate vaccine (PCV13) in preterm infants compared with term infants.

METHODS

This Phase IV, open-label, 2-arm, multicenter, parallel-group study enrolled 200 healthy infants (preterm, n = 100; term, n = 100) aged 42 to 98 days. All subjects received PCV13 at ages 2, 3, 4 (infant series), and 12 (toddler dose [TD]) months, together with routine vaccines (diphtheria-tetanus-acellular pertussis, hepatitis B, inactivated poliovirus, and Haemophilus influenzae type b vaccine and meningococcal group C conjugate vaccine).

RESULTS

Most subjects achieved an anticapsular immunoglobulin G (IgG) antibody concentration ≥ 0.35 μg/mL for all serotypes: >85% after the infant series (except preterm infants for serotypes 5, 6A, and 6B) and >97% after TD (except for serotype 3). Preterm infants had overall lower IgG geometric mean concentrations compared with term infants; however, geometric mean fold increases after TD were similar for all serotypes. Opsonophagocytic activity results were consistent with IgG results and titers increased after TD in both groups for all serotypes, including serotype 3. PCV13 was generally well tolerated, with similar safety profiles in all preterm subgroups.

CONCLUSIONS

Immune responses were lower in preterm infants than in term infants. However, the majority of subjects in both groups achieved both pneumococcal serotype-specific IgG antibody levels after the infant series that exceeded the World Health Organization-established threshold of protection and functional antibody responses. Responses were uniformly higher after TD, reinforcing the importance of a timely booster dose. PCV13 was well tolerated regardless of gestational age.

Expression of microRNA-155 precursor in peripheral blood mononuclear cells from Hepatitis C patients after antiviral treatment

Chronic hepatitis caused by Hepatitis C virus (HCV) is the main source of liver cirrhosis, hepatocellular carcinoma, and extra-hepatic diseases. After treatment-induced resolution of hepatitis C, the persistence of HCV RNA in serum and peripheral blood mononuclear cells (PBMCs) is often observed. An expression of the precursor of microRNA-155 (miR-155) called BIC can be the factor responsible for a course of HCV infection. Therefore, we assessed the relationship between BIC expression and HCV RNA status in sera and PBMCs samples of 64 hepatitis C patients treated with interferon alpha(IFN-alpha)+ribavirin. High expression of BIC in PBMCs was determined in 100% of patients that harbored HCV RNA in serum and PBMCs. Further, we found that 83% of PBMCs samples were BIC-positive in a group of patients that eliminated HCV RNA only from serum. The lowest expression of BIC was found in patients that eliminated HCV RNA from both serum and PBMCs.

Mevalonate pathway modulation is associated with hepatitis C virus RNA presence in peripheral blood mononuclear cells

Peripheral blood mononuclear cells (PBMC) constitute the main extrahepatic reservoir of hepatitis C virus (HCV). Lipid metabolism of host seems to play important role in HCV infection. The relationship between HCV presence in PBMC and the expression of mevalonate pathway has not been elucidated. The aim of this study was to investigate the association between mevalonate pathway and HCV RNA presence in PBMC after anti-HCV treatment. 67 serum and corresponding PBMC samples were collected from patients at the end of interferon alpha and ribavirin treatment. Serum total cholesterol, HDL-C and LDL-C fractions, triglycerides, as well as intracellular cholesterol and expression level of HMG-CoA reductase, geranylgeranyl pyrophosphate synthase in PBMC were measured and matched for the HCV RNA presence or absence in sera/PBMC. HCV RNA elimination from sera and PBMC was associated with higher serum cholesterol (118.5mg/dL) and LDL-C (66.42mg/dL) levels, compared to the group, where HCV RNA was detected only in PBMC (100.94 and 53.22mg/dL) or the group, where HCV RNA was found in both sera and PBMC (86.79 and 43.79mg/dL) after treatment. Increased expression of geranylgeranyl pyrophosphate synthase was found in the majority of PBMC samples that harbored HCV RNA after elimination of HCV RNA from sera. The expression of mevalonate pathway after antiviral treatment seems to be modulated depending on HCV RNA status in peripheral blood mononuclear cells.

Immunogenicity of inactivated hepatitis A vaccine in children with chronic liver disease

One and 6 months after vaccination with hepatitis A virus vaccine (HAVRIX 720 Junior), immunologic responses (anti-hepatitis A virus >/=20 mIU/ml) in children with chronic hepatitis C infection seroprotection were 92% (23/25) and 75% (9/12) in children with chronic hepatitis B infection 87% (21/24) and 88% (15/17) and in healthy children 91% (20/22) at both times. A booster dose induced seroprotection in all children.

The correlation between the numbers of some bacteria in human oral cavity and blood neutrophil count

The correlation between the number of blood polymorphonuclear granulocytes (PMNs) and the counts of oral bacteria in 92 children (33 girls and 59 boys), aged 4-15 was investigated. The groups of children comprised 44 healthy individuals and 48 children suffering from acute lymphoblastic leukaemia who were given intensive antileukaemic chemotherapy. It was found that while the number of PMNs in blood decreased, the counts of Streptococcus spp., Staphylococcus spp., mutans streptococci, Lactobacillus spp., and Actinomyces spp. in the saliva tended to increase. The similar reciprocal correlation between the number of blood PMNs and the counts of these bacteria in the saliva was found in the group of healthy children. We concluded that the blood PMNs, by influencing the number of oral PMNs which control bacteria in this habitat, influence also the number of some groups of bacteria there.