New treatments for hepatitis B and C in children and adolescents

Abstract

The treatment of chronic viral hepatitis is a rapidly evolving field. Therapy for chronic hepatitis B is indicated at times of high viral replication, as long as the patient’s aminotransferase levels are increased by more than twice the norm, and when hepatitis B e antigen (HBeAg) is positive. The treatment options for chronic hepatitis B include interferon-alpha and the nucleoside analogues lamivudine and adefovir dipivoxil. Between 26% and 38% of patients respond to treatment with interferon-alpha and nucleoside analogues; from 17% to 36% respond with antibodies to HBeAg (anti-HBe) seroconversion after 1 year. With seroconversion, HBeAg disappears and there is a dramatic decrease in HBV-DNA and usually in the aminotransferases. Further development of nucleoside analogues promises to increase the effectiveness of the therapy. Complete recovery, with conversion to antibodies to hepatitis B surface antigen (anti-HBs), occurs in about 5% of patients only after interferon-alpha therapy. The success of treatment is influenced by factors such as the origins of infection, the viral load before therapy, and the intensity of liver inflammation. Without therapy, the rate of seroconversion to anti-HBe ranges from 2.5% to 11% a year. It is becoming evident that patients with fulminant hepatitis B benefit from treatment with lamivudine. In contrast to hepatitis B, the treatment goal for chronic hepatitis C is the patient’s full recovery. Currently, depending on the HCV genotype, the combination therapy of interferon-alpha and ribavirin administered for 6–12 months has proven effective. Approximately 80% of children are infected with genotype 1a or 1b. They have a recovery rate of 45%. Genotypes 2 or 3 respond much better to treatment. More than 84% of patients can be successfully treated. Genotype 4 is relatively rare and appears to respond to treatment like genotype 1. Under certain circumstances, unsuccessfully treated patients can be treated a second time, after a number of years, with another interferon-alpha, e.g., natural human alpha interferon (Multiferon®) or consensus interferon (Inferax®) plus ribavirin. In addition, new medications such as protease and polymerase inhibitors are currently being tested in adult patients and should be available in the next few years.