Telaprevir Treatment Decays Hepatitis C Virus Faster in Blood than Liver

A recent study found that the hepatitis C virus decays during treatment faster in the bloodstream than it does in the liver, a discovery that could help pinpoint how long a patient needs to take medicine to rid the virus from the body.

The study was conducted by Andrew Talal, MD, and other researchers at Weill Cornell Medical College in New York City and the findings published in Hepatology. It was the first time scientists traced in real time how the drug telaprevir inhibits viral replication in the liver and clears the virus from the cells and plasma of infected patients, study authors said in a release.

The study looked at results from 15 patients who had genotype 1 chronic hepatitis C virus (HCV) and were treated with an FDA-approved telaprevir-based triple regimen that also included pegylated interferon alfa, and ribavirin. Researchers measured viral kinetics, resistance patterns, plasma concentrations, and host transcription profiles.

One way to determine how quickly the virus can be eradicated is by tracking the rate of decay for viral ribonucleic acid (RNA). Researchers used fine needle aspirations to get liver samples at various time points before and after treatment with the telaprevir, according to the release.

“We found that HCV RNA decay in the liver lagged behind that in the peripheral blood, which has implications for how long the virus may persist in the body and the possible duration of treatment needed,” Talal said in the statement. Higher levels of telaprevir were also found in blood when compared to the liver.

Before this study, there was no precise definition of treatment duration based upon serial measurements of the virus in the liver, according to Talal.

“This is the first time serial measurements in the liver have been performed during antiviral therapy,” Talal said. “Our findings begin to define for how long patients may need to be treated in order to achieve viral eradication.”

Approved by the FDA in 2011, telaprevir is a protease inhibitor and one of four drugs cleared to be marketed in the US in recent years for treatment of HCV, for which there is no vaccine.

Drug companies racing to develop better, quicker treatments for the virus have continued in recent months to file more applications with regulatory agencies that if approved would allow them access to a worldwide market of people infected with HCV.

Health officials estimate that at least 3 million people in the US and 150 million globally have chronic infection of the virus, which can live in the body for years without symptoms. They encourage screening for the bloodborne virus among all baby boomers born from 1945 to 1965, as well as high-risk populations that include injection drug users who could spread the virus via tainted needles.

The study was sponsored by Vertex Pharmaceuticals, the maker of Incivek (telaprevir).