Therapy Free of Side Effects of Other HCV Drugs

An investigational protease inhibitor (PI) led to viral cures in about four out of five hepatitis C virus (HCV) patients, a researcher reported here.

In a phase III study, either of two doses of faldaprevir combined with pegylated interferon and ribavirin significantly outperformed placebo, according to Peter Ferenci, MD, of the Medical University of Vienna.

But importantly, Ferenci told MedPage Today during the meeting of the European Association for the Study of the Liver, they did so without the side effects associated with earlier drugs in the class.

The efficacy results are "indeed very good," commented Mark Thursz, MD, of St. Mary's Hospital in London, who was not involved in the study but who moderated a press conference at which some details were discussed.

But the most important aspect of the results, Thursz said, is the safety profile of the drug. "This will be far better tolerated by our patients in the clinic than the earlier PIs," he told reporters.

Two protease inhibitors – telaprevir (Incivek) and boceprevir (Victrelis) – have been approved for patients with the difficult-to-treat HCV genotype 1, but they have been associated with serious and sometimes dangerous adverse events.

Both, for instance, cause significant anemia, and telaprevir has been associated with life-threatening rash that in at least two cases led to death.

But they are the only drugs so far approved that directly target HCV; the companion medications, pegylated interferon and ribavirin, are respectively an immune booster and a viral replication inhibitor.

That was the context when the industry-sponsored trial was designed, Ferenci told MedPage Today - the earlier protease inhibitors were regarded as the competitors, with interferon (given intravenously) and ribavirin alone as the standard of care.

Action Points Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal. An investigational protease inhibitor (faldaprevir) led to viral cures in about four out of five hepatitis C virus (HCV) patients, a study found. Note that faldeprevir was well-tolerated without the side effects associated with earlier protease inhibitor drugs.

Since then, he said, there has been a "revolution" in HCV, with a host of oral direct-acting agents under investigation and clinicians hoping that interferon and perhaps ribavirin can be banished from the clinic.

Indeed, Ferenci noted, research is underway to see if faldaprevir, in combination with other oral direct-acting HCV drugs, can be effective in the absence of interferon and possibly without interferon or ribavirin.

In the current study, investigators enrolled 652 patients with genotype 1 HCV and randomly assigned them for 24 weeks to get placebo or either 120 or 240 milligrams of faldaprevir daily. All patients also got then-standard therapy with interferon and ribavirin.