Adding a new antiviral treatment to standard therapy nearly doubles the response rate for hepatitis C patients, according to a new study.

Hepatitis C virus affects about 170 million people worldwide. Genotype 1 is the most common form that is prevalent in North America and Europe. It is also the most difficult to treat.

The standard regimen for genotype 1 hepatitis C consists of peginterferon and ribavirin, but fewer than half of patients given the treatment achieve a sustained response. Researchers wanted to know if adding the NS3 protease inhibitor known as boceprevir would improve outcomes for patients.

Results from the trial, which was conducted in 67 sites in the U.S., Canada and Europe, showed adding boceprevir to the standard regimen improved rates of sustained virological response (SVR). However, those who received boceprevir had higher rates of anemia and were more likely to have a distorted sense of taste.

"The results of this phase 2 trial have shown that an optimum dose of boceprevir (800 mg three times a day), when added to the standard of care for treatment of chronic genotype 1 hepatitis C virus, significantly increased SVR in both 28-week and 48-week regimens compared with the control of peginterferon alfa-2b and ribavirin," authors of the study concluded.

The researchers say, in most patients, adding boceprevir to standard therapy is safe and effective for use up to 48 weeks.

SOURCE: The Lancet, August 8, 2010