FDA Approves Telaprevir for Treatment of hepatitis C

The US Food and Drug Administration (FDA) has approved telaprevir (Incivek, Vertex) for the treatment of hepatitis C virus (HCV) infection. The approval comes 1 week after the approval of boceprevir (Victrelis, Merck), also for HCV, and is the second drug to be approved for HCV in 20 years.

Telaprevir is approved for the treatment of chronic hepatitis C genotype 1 infection, in combination with peginterferon alfa and ribavirin, in patients aged 18 years and older with compensated liver disease, including cirrhosis, who are treatment-naive or who have been previously treated with interferon-based treatment.

The FDA’s approval on May 23 was based on the Antiviral Drugs Advisory Committee’s unanimous 18 to 0 vote on April 28 recommending that telaprevir should receive FDA approval for this indication.

Trial data were collected from three phase 3 randomized trials, conducted in about 2250 previously treated and untreated patients (1797 patients who received telaprevir combination treatment and 493 who received peginterferon alfa and ribavirin alone). Two of the trials were in treatment-naive patients and 1 was in previously treated patients (relapsers, partial responders, and null responders).

In the studies, telaprevir was administered at a dose of 750 mg every 8 hours; the peginterferon alfa-2a dose was 180 µg/week, and the ribavirin dose was 1000 mg/d in patients weighing less than 75 kg or 1200 mg/d in patients weighing 75 kg or more.

Compared with the control group, receiving ribavirin plus pegylated interferon, the patients who also received telaprevir had a significantly higher rate of sustained virologic response of about 80% or more. The sustained virologic response rate for patients treated with telaprevir across all studies, and across all patient groups, was 20% to 45% higher than the current standard of care.

“Major Step Forward”

“With the approval of [telaprevir], there are now 2 important new treatment options for hepatitis C that offer a greater chance at a cure for some patients with this serious condition,” Edward Cox, MD, MPH, director, Office of Antimicrobial Products in FDA’s Center for Drug Evaluation and Research, said in an agency news release. “The availability of new therapies that significantly increase responses while potentially decreasing the overall duration of treatment is a major step forward in the battle against chronic hepatitis C infection.”

It may be possible to shorten telaprevir treatment from 48 weeks to 24 weeks in most patients, the FDA news release states. Among previously untreated patients, 60% achieved an early response and received only 24 weeks of treatment (compared to the standard of care of 48 weeks). The sustained virologic response for these patients was 90%.

Common adverse events with telaprevir when used in combination with ribavirin and pegylated interferon include anemia, nausea, fatigue, headache, diarrhea, pruritus, and anal or rectal irritation and pain.

“Telaprevir will likely be very well received as a treatment option in addition to ribavirin and peginterferon alfa for patients with genotype 1 HCV previously unresponsive to the standard of care,” said McKenzie C. Ferguson, PharmD, assistant professor of pharmacy practice at the Drug Information & Wellness Center, Southern Illinois University, Edwardsville, Illinois.

“Additionally, studies in previously untreated patients have demonstrated that we can now treat genotype 1 patients for shorter durations (based on early virologic response) to achieve sustained virologic response or ‘cure,'” she told Medscape Medical News. “This is a dramatic improvement as many of the challenges to treating HCV is battling adherence issues and adverse drug effects for long durations of treatment.”

Dr. Ferguson said she believes both drugs will show similar therapeutic effect profiles, but as use of these agents increases, more insight will be available regarding which to use in certain patients. “At this point, serious skin reactions with telaprevir are a concern and have not been observed to the same extent with boceprevir,” she said.

Both telaprevir and boceprevir interfere with the ability of the HCV to replicate by inhibiting a key viral enzyme (NS3/4A serine protease).