| Experimental
HCV Protease Inhibitor VX-950 Demonstrates Potent Anti-HCV Activity
Interim
results of a Phase Ib study indicate that the experimental
hepatitis C virus protease inhibitor VX-950 has potent
anti-HCV activity and is well tolerated, according to an announcement
from drug maker Vertex Pharmaceuticals. Within three days
of treatment, the median reduction in HCV-RNA was greater
than 3 log10 in all three VX-950 dose groups.
As
an oral drug that shows potency and no serious adverse side
effects, VX-950 has the potential to become a breakthrough
therapy for chronic hepatitis C.
The
study enrolled 34 patients with chronic genotype 1 HCV infection
who were treated for 14 days with placebo or one of three
dose regimens of VX-950. HCV
genotype1 infection is the most difficult strain of HCV
to treat and the most prevalent strain in the United States,
Western Europe and Japan.
Every
patient receiving VX-950 achieved greater than a 2 log10 reduction
in HCV-RNA within the first three days of treatment, according
to Vertex.
Complete
results from the study will be presented on May 17 at DDW
2005 in Chicago. In accordance with the DDW embargo policy
of the meeting, the specific data from the trial beyond what
is described in today’s announcement from Vertex will not
be disclosed until the DDW presentation. HIV and Hepatitis.com
will post daily reports from DDW 2005, beginning Monday, May
16, 2005.
Study Design
The Phase Ib clinical trial was a double-blind, randomized
placebo-controlled study designed to evaluate the tolerability,
pharmacokinetics
and effect on viral
kinetics of three doses of VX-950 -- 450 mg every 8 hours,
1250 mg every 12 hours, or 750 mg every 8 hours -- over a
period of 14 days, with additional post-treatment follow-up.
A
key goal of the study was to assess different dosing levels
and frequencies for VX-950 to provide
insight into dose selection for future monotherapy and combination
therapy studies. Thirty-four patients with chronic genotype
1 hepatitis C virus infection were enrolled in the study;
six patients received placebo and 28 patients received VX-950.
The study was conducted at three centers in Europe. The trial
included treatment-experienced and treatment-naive HCV-infected
patients.
Results
Principal results of the Phase Ib clinical trial are as follows:
· VX-950
was well-tolerated across all three dose groups with no
serious adverse events reported, and no treatment discontinuations.
· Treatment
with VX-950 also resulted in significant reductions
in plasma HCV-RNA. Within three days of treatment, the
median reduction in HCV-RNA was greater than 3 log10 in
all three VX-950 dose groups.
· In
the dose group receiving 750 mg of VX-950 every 8 hours,
there was a further reduction in viral levels between days
3 and 14 of treatment, with mean and median HCV-RNA reductions
of greater than 4 log10 at day 14.
· Trough
plasma concentrations of VX-950 were highest in the 750
mg every 8 hour dose group. In the 450 mg q8h and 1250 mg
q12h dose groups, maximal effects were seen between days
3 and 7 of treatment.
· Subsequently,
there was an increase of approximately 1 log10 in median
HCV-RNA between days 7 and 14 evident in both groups.
Full
analysis of the study, including a detailed pharmacokinetic
and viral sequencing evaluation, is underway.
"Vertex
is committed to developing innovative compounds for the treatment
of chronic HCV infection. VX-950, one of the most advanced
agents in a promising new class of direct antivirals, underscores
that commitment," said Joshua Boger, Ph.D., Chairman
and Chief Executive Officer of Vertex. "The demonstration
of antiviral activity in this early clinical study is highly
encouraging, and we look forward to sharing these data in
greater detail at DDW next week."
Based
on the results of the Phase Ib clinical study, the Company
plans to explore the development of VX-950 as monotherapy
and in combination with other HCV treatments. Vertex plans
to consult with the US FDA and European regulatory authorities
on the Company's development plans.
Vertex
expects to file an investigational new drug (IND) application
in the second half of 2005
to support Phase II clinical development of VX-950 in the
United States. In collaboration with Vertex, Mitsubishi Pharma
Corporation is developing VX-950 in Japan and certain Far
East countries.
About Vertex
Vertex
Pharmaceuticals Incorporated is a global biotechnology company
committed to the discovery and development of breakthrough
small molecule drugs for serious diseases. The Company's strategy
is to commercialize its products both independently and in
collaboration with major pharmaceutical companies. Vertex's
product pipeline is principally focused on viral diseases,
inflammation, autoimmune diseases and cancer. Vertex co-promotes
the HIV protease inhibitor fosamprenavir (Lexiva) with GlaxoSmithKline.
05/11/05
Sources
PR Newswire-FirstCall.
May 10, 2005.
http://www.vrtx.com
|
