| [ Summary ] |
Pegylated intefferon (PEG-IFN) has the advantage that its plasma half-life is prolonged, which induces high anti-viral activity and low rates of symptomatic adverse events. PEG-IFN alpha 2 a monotherapy has been performed on Japanese chronic hepatitis C patients since December, 2003. There were high sustained virological responses in genotype 2 a and 2 b infected patients, HCV RNA rates were negative at 6 weeks after starting administration of PEG-IFN. SVR rates were over 80% in spite of 24 week treatments. In genotype 1 b infections, however, it is possible to achieve SVR in patients with high viral loads at a rate of only 10 %, which is less frequent compared to the SVR for genotype 2 a and 2 b infections. In spite of achieving low SVR rates, PEG-IFN monotherapy is effective in preventing progression to cirrhosis or development of hepatocellular carcinoma, because serum ALT may be kept within twice the upper limit and serum alfa-fetoproteins may be reduced. Interstitial peumonitis and thrombocytopenia are frequently observed during administration of PEG-IFN, thus close follow up is necessary during administration. |