The Hepatitis C Drug Development Pipeline (Hcv Pipeline‪)‬

Current hepatitis C treatment has many drawbacks, including significant side effects, high cost, and the need for injections of pegylated interferon. While the major clinical trials of pegylated interferon and ribavirin show about a 50% success rate in clearing the virus--deemed a sustained virologic response (SVR)--in real-life clinical settings, SVR rates are frequently lower. Moreover, treatment outcomes are poorer for African-Americans and for people with genotype 1, high viral loads, and/or HIV co-infection. Because of toxicities, including psychiatric side effects, treatment is often contraindicated for many people with hepatitis C. As a result, many people avoid or delay hepatitis C treatment, and only a relatively small proportion of people with hepatitis C--perhaps 10%--have been treated to date, with many failing to achieve an SVR. Thus, there is an urgent need for new, more effective, and better-tolerated treatments. The hepatitis C virus (HCV) offers a number of potential targets for drug development. HCV undergoes a relatively simple replication cycle: cell entry; translation and cleavage of viral proteins; replication of viral RNA; and assembly and release of new viruses. Each of these stages in the replication cycle are, in theory, susceptible to inhibition by new drugs, though some aspects of replication--particularly cell entry and assembly and release--are still not well understood. In addition, novel treatments could stimulate more effective immune responses targeting HCV and facilitating viral clearance. Finally, in lieu of eradicating HCV, new drugs could benefit people who do not respond to current therapy by slowing or ameliorating liver damage.