%0 Journal Article %T Direct Acting Antivirals for the Treatment of Chronic Viral Hepatitis %A Peter Karayiannis %J Scientifica %D 2012 %I Hindawi Publishing Corporation %R 10.6064/2012/478631 %X The development and evaluation of antiviral agents through carefully designed clinical trials over the last 25 years have heralded a new dawn in the treatment of patients chronically infected with the hepatitis B and C viruses, but not so for the D virus (HBV, HCV, and HDV). The introduction of direct acting antivirals (DDAs) for the treatment of HBV carriers has permitted the long-term use of these compounds for the continuous suppression of viral replication, whilst in the case of HCV in combination with the standard of care [SOC, pegylated interferon (PegIFN), and ribavirin] sustained virological responses (SVRs) have been achieved with increasing frequency. Progress in the case of HDV has been slow and lacking in significant breakthroughs.This paper aims to summarise the current state of play in treatment approaches for chonic viral hepatitis patients and future perspectives. 1. Introduction Conservative estimates of the number of individuals worldwide who are thought to be chronically infected with either HBV or HCV are placed at over 350 [1] and 200 [2] million, respectively. It has long been established through epidemiological surveys that these patients are at increased risk of developing cirrhosis, hepatic decompensation, and hepatocellular carcinoma (HCC). About 1 million people die per year as a result of HBV-related liver pathologies [3]. In resource-limited countries, HBV infection accounts for 30% of cirrhotic patients and 53% of those with HCC [4]. On the other hand, HCV is responsible for approximately 350000 deaths every year [5]. The only means of preventing these un-necessary deaths is therapeutic intervention through the use of immune modulators and direct acting antivirals (DDAs). The ultimate goals of treatment are to achieve a sustainable suppression of replication and remission of liver disease in the case of HBV, and complete eradication of the virus from the liver in the case of HCV. For many years, the only choice for treatment was interferon alpha (IFN¦Á), lymphoblastoid initially and recombinant subsequently, both of which have more recently been superceded by the pegylated form (PegIFN), which requires intramuscular injection only once a week as opposed to three times a week with the previous forms. Interferon has not only immunomodulatory, but also antiproliferative and antiviral effects. It acts by promoting cytotoxic T-cell activity for lysis of infected hepatocytes and by stimulating cytokine production for control of viral replication. DDAs on the other hand constitute a more recent development based on increasing %U http://www.hindawi.com/journals/scientifica/2012/478631/