Treatment of hepatitis C in children

Breakthroughs and challenges in the management of pediatric viral hepatitis

Chronic infections by hepatitis B virus (HBV) and hepatitis C virus (HCV) major causes of advanced liver disease and mortality worldwide. Although regarded as benign infections in children, their persistence through adulthood is undoubtedly of concern. Recent advances in HCV treatment have restored the visibility of these conditions and raised expectations for HBV treatment, which is currently far from being curative. Herein we describe direct-acting antivirals available for pediatric HCV (sofosbuvir/ledipasvir, sofosbuvir/velpatasvir, glecaprevir/pibrentasvir) and their real-world use. A critical review of the HBV pediatric classification is provided. Anti-HBV investigational compounds are reviewed in light of the pathophysiology in the pediatric population, including capsid assembly modulators, antigen secretion inhibitors, silencing RNAs, and immune modifiers. Recommendations for screening and management of immunosuppressed children or those with other risk factors or comorbidities are also summarized.

Epidemiology and natural history of hepatitis C virus infection among children and young people

BACKGROUND & AIMS

Chronic hepatitis C virus (HCV) infection is a global health burden. Although HCV infection rarely contributes to morbidity during childhood, most HCV-infected children develop chronic HCV with a lifetime risk of liver disease. Little is known about the development of long-term liver disease and the effect of treatment in patients infected with HCV in childhood.

METHOD

This study was a retrospective review of patients infected with HCV in childhood enrolled in HCV Research UK. A total of 1,049 patients were identified and included.

RESULTS

The main routes of infection were intravenous drug use (53%), blood product exposure (24%) and perinatal infection (11%). Liver disease developed in 32% of patients, a median of 33 years after infection, irrespective of the mode of infection. Therefore, patients with perinatal exposure developed cirrhosis at an earlier age than the rest of the risk groups. The incidence of hepatocellular carcinoma (HCC) was 5%, liver transplant 4% and death occurred in 3%. Overall, 663 patients were treated (55% with interferon/pegylated interferon and 40% with direct-acting antivirals). Sustained virological response (SVR) was achieved in 406 (75%). There was a higher mortality rate among patients without SVR vs. those with SVR (5% vs. 1%, p = 0.003). Treatment was more effective in patients without cirrhosis and disease progression was less frequent (13%) than in patients with cirrhosis at the time of therapy (28%) p < 0.001. Patients with cirrhosis were more likely to develop HCC, require liver transplantation, or die.

CONCLUSION

HCV infection in young people causes significant liver disease, which can now be prevented with antiviral therapy. Early treatment, especially before development of cirrhosis is essential. Detection of HCV should be aimed at relevant risk groups and antiviral therapy should be made available in childhood to prevent long-term liver disease and spread of HCV.

LAY SUMMARY

Chronic hepatitis C virus (HCV) infection is a global health problem, which can now be treated with potent direct-acting antiviral drugs. This study demonstrates that HCV infection in childhood causes serious liver disease in 32% of patients, a median of 33 years after infection, irrespective of age, mode and route of infection. Disease outcomes were better in patients treated before the development of advanced liver disease. Antiviral therapy should be made available in childhood to prevent long-term liver disease and the spread of HCV.

Hepatitis C Viral Infection in Children: Updated Review

Hepatitis C virus (HCV) infection is a major medical challenge affecting around 200 million people worldwide. The main site of HCV replication is the hepatocytes of the liver. HCV is a positive enveloped RNA virus from the flaviviridae family. Six major HCV genotypes are implicated in the human infection. In developed countries the children are infected mainly through vertical transmission during deliveries, while in developing countries it is still due to horizontal transmission from adults. Minimal nonspecific and brief symptoms are initially found in approximately 15% of children. Acute and chronic HCV infection is diagnosed through the recognition of HCV RNA. The main objective for treatment of chronic HCV is to convert detected HCV viremia to below the detection limit. Children with chronic HCV infection are usually asymptomatic and rarely develop severe liver damage. Therefore, the benefits from current therapies, pegylated-Interferon plus ribavirin, must be weighed against their adverse effects. This combined treatment offers a 50-90% chance of clearing HCV infection according to several studies and on different HCV genotype. Recent direct acting antiviral (DAA) drugs which are well established for adults have not yet been approved for children and young adults below 18 years. The most important field for the prevention of HCV infection in children would be the prevention of perinatal and parenteral transmission. There are areas of focus for new lines of research in pediatric HCV-related disease that can be addressed in the near future.

Treatment of Hepatitis C Virus Infection in Children Less than 12 Years of Age in Developing Countries

The treatment of hepatitis c virus (HCV) infection in children is difficult as few options are available. The standard therapy is combination pegylated interferon (PEG-IFN) α-2a or 2b and ribavirin, and the duration of therapy depends on HCV genotype. New oral drug therapies available for adults have still not been approved for treatment in children. Here, we review the causes of HCV infection in children, the therapeutic options for children, and the side effects of these treatments. The problems faced by physicians managing HCV infection in children less than 12 years of age in a developing country are also discussed.

Safety and efficacy of Hansenula-derived PEGylated-interferon alpha-2a and ribavirin combination in chronic hepatitis C Egyptian children

AIM: To investigate the safety and efficacy of a Hansenula-derived PEGylated (polyethylene glycol) interferon (IFN)-alpha-2a (Reiferon Retard) plus ribavirin customized regimen in treatment-naïve and previously treated (non-responders and relapsers) Egyptian children with chronic hepatitis C infection.

METHODS: Forty-six children with chronic hepatitis C virus (HCV) infection were selected from three tertiary pediatric hepatology centers. Clinical and laboratory evaluations were undertaken. Quantitative polymerase chain reaction (PCR) for HCV-RNA was performed before starting treatment, and again at 4, 12, 24, 48, 72 wk during treatment and 6 mo after treatment cessation. All patients were assigned to receive a weekly subcutaneous injection of PEG-IFN-alpha-2a plus daily oral ribavirin for 12 wk. Thirty-four patients were treatment-naïve and 12 had a previous treatment trial. Patients were then divided according to PCR results into two groups. Group I included patients who continued treatment on a weekly basis (7-d schedule), while group II included patients who continued treatment on a 5-d schedule. Patients from either group who were PCR-negative at week 48, but had at least one PCR-positive test during therapy, were assigned to have an extended treatment course up to 72 wk. The occurrence of adverse effects was assessed during treatment and follow up. The study was registered at www.ClinicalTrials.gov (NCT02027493).

RESULTS: Only 11 out of 46 (23.9%) patients showed a sustained virological response (SVR), two patients were responders at the end of treatment; however, they were lost to follow up at 6 mo post treatment. Breakthrough was seen in 18 (39.1%) patients, one patient (2.17%) showed relapse and 14 (30.4%) were non-responders. Male gender, short duration of infection, low viral load, mild activity, and mild fibrosis were the factors related to a better response. On the other hand, patients with high viral load and absence of fibrosis failed to respond to treatment. Before treatment, liver transaminases were elevated. After commencing treatment, they were normalized in all patients at week 4 and were maintained normal in responders till the end of treatment, while they increased again significantly in non-responders (P = 0.007 and 0.003 at week 24 and 72 respectively). The 5-d schedule did not affect the response rate (1/17 had SVR). Treatment duration (whether 48 wk or extended course to 72 wk) gave similar response rates (9/36 vs 2/8 respectively; P = 0.49). Type of previous treatment (short acting IFN vs PEG-IFN) did not affect the response to retreatment. On the other hand, SVR was significantly higher in previous relapsers than in previous non-responders (P = 0.039). Only mild reversible adverse effects were observed and children tolerated the treatment well.

CONCLUSION: Reiferon Retard plus ribavirin combined therapy was safe. Our customized regimen did not influence SVR rates. Further trials on larger numbers of patients are warranted.

Efficacy of pegylated interferon α-2b and ribavirin in chronic hepatitis C virus (genotypes 1 and 4) infection

BACKGROUND AND OBJECTIVE

The course of chronic hepatitis C in children is often mild or asymptomatic, but may lead to liver cirrhosis and neoplasm. The aim of our study was retrospective evaluation of treatment efficacy using pegylated interferon (IFN)-α2b with ribavirin in children and adolescents with chronic hepatitis C, both treatment naïve and re-treated.

METHODS

The study comprised 79 patients with chronic hepatitis C ages 8 to 18 years (43 patients re-treated; 54 infected with genotype 1 hepatitis C virus and 25 with genotype 4), treated with pegylated IFN-α2b (1.5 μg · kg⁻¹ · week⁻¹) plus ribavirin (15 mg · kg⁻¹ · day⁻¹) for 48 weeks. The primary endpoint was sustained virologic response (SVR).

RESULTS

Early viral response (EVR) was observed in 43.1% and end-of-treatment response in 47.9% of patients. In 44.3% of patients, SVR was achieved, which was maintained for at least the next 6 months. Patients not treated before significantly more frequently attained EVR, end-of-treatment response, and SVR (64%, 65.6%, and 63.9%, respectively) as compared with re-treated patients (30%, 33.3%, and 27.9%, respectively). Among 28 patients who attained EVR, 23 achieved SVR. In 2 patients, despite lack of EVR, SVR was observed. There were numerous adverse effects. They were not so severe as to discontinue therapy.

CONCLUSIONS

Combined therapy with pegylated IFN-α2b and ribavirin in patients with chronic hepatitis C, infected with hepatitis C virus genotypes 1 and 4, was more effective in treatment-naïve patients (63.9%) as compared with re-therapy cases (27.9%). SVR was maintained for at least the next 6 months in all of the patients. The applied treatment has limited efficacy and evokes numerous adverse effects; thus, search for new methods of treatment is mandatory.

Evaluating progression of liver disease from repeat liver biopsies in children with chronic hepatitis C: a retrospective study

Clinical and histologic progression of liver disease in untreated children with chronic hepatitis C virus (HCV) infection is poorly documented. The aim of this retrospective study was to characterize changes in liver histology over time in a cohort of HCV-infected children who had more than one liver biopsy separated by over 1 year. Forty-four untreated children without concurrent liver diseases, who had repeat liver biopsies at eight U.S.-based medical centers, were included. Biopsies were scored by a single pathologist for inflammation, fibrosis, and steatosis and were correlated with demographic data including age at biopsy, time from infection to biopsies, and laboratory values such as serum alanine aminotransferase (ALT). Mode of transmission was vertical in 25 (57%) and from transfusions in 17 children (39%). Genotype 1 was present in 30/35 (84%) children. The mean age at first and final biopsy was 8.6 and 14.5 years, respectively, and the mean interval between biopsies was 5.8 ± 3.5 years. Duration of infection to biopsy was 7.7 and 13.5 years, respectively. Laboratory values did not change significantly between the biopsies. Inflammation was minimal in about 50% at both timepoints. Fibrosis was absent in 16% in both biopsies, limited to portal/periportal in 73% in the first biopsy, and 64% in the final biopsy. Between the two biopsies, the proportion of patients with bridging fibrosis/cirrhosis increased from 11% to 20% (P = 0.005).

CONCLUSION

Although in aggregate this cohort did not show significant histologic progression of liver disease over 5 years, 29.5% (n = 13) of children showed an increase in severity of fibrosis. These findings may have long-term implications for the timing of follow-up biopsies and treatment decisions.

Impact of IL-28B polymorphisms on pegylated interferon plus ribavirin treatment response in children and adolescents infected with HCV genotypes 1 and 4

IL-28B polymorphisms are predictors of response to therapy in adults infected with hepatitis C. We do not know whether they are markers of response to therapy in children and adolescents. The aim of this study was to determine whether single-nucleotide polymorphisms (SNPs) in the IL-28B gene could influence the probability of response to therapy compared with other known baseline prognostic factors and correlate with clinical findings in pediatric patients infected with hepatitis C virus (HCV) genotypes 1 or 4. We determined three SNPs of IL-28B (rs12979860, rs12980275, and rs8099917) in 82 patients with chronic HCV infection treated with pegylated interferon alpha and ribavirin (peg-IFNα/RBV). Treatment response and clinical data were analyzed. Overall, sustained virological response (SVR) was achieved by 45 % of patients infected with difficult-to-treat HCV genotypes 1 and 4. Except for IL-28B polymorphisms, there was no association of SVR with any other clinical data. IL-28B rs12979860 CC [odds ratio (OR), 6.81; p = 0.001] and rs8099917 TT (OR, 3.14; p = 0.013) genotypes were associated with higher SVR rates. IL-28B rs12980275 was not significantly associated with SVR (p = 0.058). Only the distribution between CC and CT-TT genotypes of rs12979860 significantly differentiated patients achieving early virological response (EVR) (OR, 10.0; p = 0.011). Children with the rs12979860 CC genotype had significantly higher baseline viral load compared with CT-TT patients (p = 0.010). In children and adolescents chronically infected with HCV genotypes 1 and 4, IL-28B rs12979860 and rs8099917 polymorphisms were the only predictors of response to peg-IFN/RBV.

Current treatment options and response rates in children with chronic hepatitis C

Vertical transmission has become the most common mode of transmission of hepatitis C virus (HCV) in children. The rate of perinatal transmission from an HCV-infected mother to her child ranges from 2% to 5% and the prevalence of HCV in children in developed countries ranges between 0.1% and 0.4%. Spontaneous viral clearance seems to be dependent on the genotype and has been reported between 2.4%-25%. For chronically infected patients, treatment with recombinant polyethylene glycol (PEG)-interferon α-2b and daily ribavirin has now been approved as standard treatment for children 2-17 years of age. In five large prospective studies, a total of 318 children and adolescents aged 3-17 years were treated either with subcutaneous PEG-interferon α-2b at a dose of 1-1.5 μg/kg or 60 μg/m² once a week in combination with oral ribavirin (15 mg/kg per day) or PEG-interferon α-2a with ribavirin. Subjects with genotype 1 and 4 received the medication for 48 wk and individuals with genotype 2 and 3 mainly for 24 wk. Overall sustained viral response (SVR) was achieved in 193/318 (60.7%) of treated patients. Stratified for genotype; 120/234 (51%) with genotype 1, 68/73 (93%) with genotype 2/3, and 6/11 (55%) with genotype 4 showed SVR. Relapse rate was between 7.7% and 17%. Overall, treatment was well tolerated; however, notable side effects were present in approximately 20%. According to recent experiences in the treatment of chronic hepatitis C in children and adolescents, a combination of PEG-interferon α with ribavirin has been found to be well tolerated and highly efficacious, particularly in individuals with genotype 2/3. Thus, this treatment can be recommended as standard of care until more effective treatment options will become available for genotype 1 patients.

Management of chronic hepatitis C in childhood: the impact of therapy in the clinical practice during the first 2 decades

BACKGROUND AND AIM

Treatment of chronic hepatitis C in children is controversial and its role in the clinical practice is unknown. We retrospectively investigated the impact of treatment in a large cohort of children with chronic hepatitis C over the past 20 years.

METHODS

376 hepatitis C virus RNA positive children were recruited consecutively in five Italian centres since 1990 and followed for 1-17 years.

RESULTS

86 (23%) subjects were treated: 73 with recombinant interferon alone and 13 with pegylated-interferon and ribavirin. Sustained clearance of hepatitis C virus RNA was observed in 25% of the former, in 92% of the latter and in 9% of untreated cases (p < 0.001). Loss of viraemia was recorded in all children with genotype 2-3 and in 6 of 7 with hepatitis C virus genotype 1 treated with combination therapy. At last evaluation 45% of patients were young adults and 15% had cleared viraemia. Overall, 152 (40%) were putative candidates to therapy.

CONCLUSIONS

Few Italian children with chronic hepatitis C have been treated in the past 20 years. The poor propensity to spontaneous clearance of viraemia and the efficacy of combination therapy should encourage to consider treatment in attempt to shorten the duration of viral replication.

Chronic hepatitis C virus infection in children and adolescents: Epidemiology, natural history, and assessment of the safety and efficacy of combination therapy

Hepatitis C virus (HCV) is the most common cause of chronic liver disease of infectious etiology in children. Most of the children infected with HCV are asymptomatic, and only a few of them develop signs and symptoms of end-stage liver disease early in life. It is not possible to predict either in which patients HCV infection will have a bad outcome or the critical time in early adulthood when disease progression will accelerate. The experiences with therapy in children with chronic hepatitis C are based on earlier and continuing data from adult trials. The currently recommended treatment for chronic HCV infection in adults is the combination of peginterferon-á and ribavirin. The choice of this regimen is based on the results of randomized clinical trials that demonstrated the superiority of this combination treatment over standard interferon-á and ribavirin. Recently, results of pivotal, multicenter, interventional open-label studies on combined treatment with peginterferon-á and ribavirin in children have been published, and the US Food and Drug Administration and the European Medicines Agency have approved the combination therapy in those older than 3 years. The aim of this review is to evaluate critically the available data regarding the safety and efficacy of combination treatment with peginterferon-á and ribavirin in children.