Over 150 million people are estimated to be infected with the Hepatitis C virus. During the early stages of infection, the majority of people are free of symptoms but a significant number will later develop cirrhosis and possibly liver cancer.
Treatment is currently a combination of pegylated interferon-α and ribavirin, although several alternative therapies are being developed. Some of the more promising amongst these directly target essential viral enzymes such as the viral protease and polymerase.
The non-structural protein NS4B is an integral membrane protein that also plays a critical role in viral replication.
A new report shows that NS4B binds to viral RNA and describes the use of high-throughput microfluidic screening to identify compounds that inhibit this binding. 18 compounds that substantially reduced NS4B binding to its target RNA were discovered, and one of these compounds, clemizole, was found to inhibit replication of Hepatitis C virus in cell culture whilst showing little cellular toxicity.
Clemizole is an H1 histamine receptor antagonist and, because it has already been tested in people, it could be rapidly evaluated as a treatment for Hepatitis C infection.