Vertex: Phase 1b trial of VX-950 with pegylated interferon shows rapid drop in hepatitis C viral levels

By E. Janene Geiss

Philadelphia, Jan. 9 - Vertex Pharmaceuticals Inc. said Monday that new data show that VX-950, an investigational oral hepatitis C virus protease inhibitor, dosed in combination with pegylated interferon alfa-2a achieved a rapid and dramatic reduction in plasma viral RNA levels in patients with chronic genotype 1 hepatitis C infection.

In the phase 1b study, the combination of VX-950 and peg-IFN produced an initial median reduction in plasma viral RNA of more than 3 log10 in the first two days, followed by continued decline to a median 5.5 log10 reduction in RNA at day 14, which equates to a 300,000-fold reduction in viral levels, according to a company news release.

The majority of patients, six out of eight, receiving the combination achieved viral RNA levels below the limit of quantitation at 14 days, with four out of eight patients achieving viral RNA levels below the limit of detection, officials said.

The antiviral activity of the combination through 14 days was significantly greater than the activity of VX-950 administered as a single agent and much greater than peg-IFN alone. In addition, officials said VX-950 appeared to be well-tolerated when dosed alone and in combination with pegylated interferon in the study.

The full data set will be presented at a medical conference later this year, officials said.

"These data show that VX-950, in combination with pegylated interferon, produced a very rapid viral response in each of these genotype 1 patients, who are historically the most difficult to treat effectively," Henk W. Reesink, associate professor of medicine at Academic Medical Center in Amsterdam and a lead investigator for the study, said in the release.

The 14-day, randomized, blinded, placebo-controlled phase 1b study enrolled 20 treatment-naïve patients with genotype 1 HCV, the most prevalent and difficult-to-treat form of hepatitis C infection.

Patients were randomized to receive a new tablet formulation of VX-950 at a dose of 750 mg every eight hours in combination with a standard dose of pegylated interferon, the same dose of VX-950 administered alone or a standard dose of pegylated interferon alone, officials said.

A preliminary safety review has been conducted that indicates that the treatment was well-tolerated, officials said. All patients completed dosing and no serious adverse events were reported.

Vertex said it is conducting a broad phase 2 development program designed to establish the safety and antiviral activity of VX-950 in studies of up to three months duration.

In the next few months, Vertex said it expects to initiate a three-month phase 2 trial with more than 200 participants that will study VX- 950 dosed in combination with pegylated interferon, both with and without ribavirin, another standard hepatitis C treatment. This study will include a comparison to the current standard of care in hepatitis C treatment.

Additionally, a 12-patient, 28-day phase 2 trial of VX-950 plus pegylated interferon and ribavirin has now completed enrollment and preliminary data from this study are anticipated in the first quarter, officials said.

In December 2005, VX-950 received Fast Track designation from the U.S. Food and Drug Administration.

Vertex is a Cambridge, Mass., biotechnology company focused on the development of small molecule drugs for serious diseases.

© 2015 Prospect News.
All content on this website is protected by copyright law in the U.S. and elsewhere. For the use of the person downloading only.
Redistribution and copying are prohibited by law without written permission in advance from Prospect News.
Redistribution or copying includes e-mailing, printing multiple copies or any other form of reproduction.