Posted: 14-Dec-2006 << BACK
Vertex Pharmaceuticals today announced results from a
planned interim safety analysis from PROVE 1, an ongoing Phase 2b clinical
trial of the investigational hepatitis C virus (HCV) protease inhibitor
telaprevir (VX-950):
* In the telaprevir dosing arms, the incidence of treatment
discontinuations due to adverse events was 9% and the incidence of
serious adverse events was 3%.
* At week 12, 65 of the 74 patients (88%) for whom data was available in
the telaprevir groups demonstrated undetectable HCV RNA (less than 10
IU/mL; Roche Taqman).
Interim Safety and Antiviral Results
In accordance with the PROVE 1 study design, an interim safety and
antiviral activity analysis has been conducted, and the data have been
reviewed by the independent data monitoring committee overseeing the trial.
A total of 250 patients were enrolled and in addition to Peg-interferon
alfa-2a (peg-IFN) + ribavirin (RBV) received at least one dose of
telaprevir or placebo in the study. In the data reported, patients in all
three telaprevir containing groups were pooled together (n=175) and the
results were compared to the results in the control arm of peg-IFN + RBV
and placebo (n=75). At the time of the data cut-off for the safety
analysis, approximately 100 patients had completed 12 weeks on-study and
more than 200 patients had completed 8 weeks.
The most common adverse events were similar in type between the two
groups and were characteristic of the known side effects of interferon and
ribavirin. Of these, the adverse events that were more commonly reported in
the telaprevir groups included gastrointestinal disorders and rash. In the
telaprevir groups, as of the cut-off date, 9% of patients had discontinued
treatment due to adverse events, compared to 3% of patients in the control
arm. The difference between the two groups is due to the greater number of
discontinuations due to rash, gastrointestinal disorders, and anemia in the
telaprevir arms compared to the control arm. Three percent (3%) of patients
in the telaprevir arms discontinued due to rash, the most common adverse
event leading to treatment discontinuation in the study. Serious adverse
events were noted in 3% of patients in the telaprevir groups and 1% of
patients in the control group.
The table below summarizes available HCV RNA results at week 12:
Of the 74 patients in the telaprevir groups for whom data were
available at the end of 12 weeks, 65 (88%) demonstrated undetectable HCV
RNA (less than 10 IU/mL; Roche Taqman), compared to 17 of 33 (52%) of
patients in the control arm. Vertex expects that further results for the
PROVE 1 clinical trial will be presented at a medical forum in 2007.
About the PROVE 1 Study
PROVE 1 is a four-arm, double-blind, placebo-controlled Phase 2b
clinical trial of telaprevir (VX-950) in treatment-naive patients with
genotype 1 HCV infection. The protocol placed no restriction on patient
entry into the trial based on weight, race/ethnicity or baseline viral
load. In the trial, telaprevir was dosed in combination with pegylated
interferon-2a (peg-IFN-2a) and ribavirin (RBV). The primary objective of
PROVE 1 is to assess the proportion of patients in each study arm who
achieve a sustained viral response (SVR), defined as undetectable (less
than 10 IU/mL, as measured by the Roche TaqMan assay) HCV RNA 24 weeks
after the completion of dosing. The study was fully enrolled in September
2006 and is ongoing at approximately 35 centers in the U.S. All subjects
will have completed telaprevir dosing by the third week of December 2006. A
full description of the PROVE 1 trial design can be found in Vertex's May
23, 2006 press release.
About Telaprevir (VX-950)
Telaprevir (VX-950) is an investigational oral inhibitor of HCV
protease, an enzyme essential for viral replication, and is one of the most
advanced investigational agents in development that specifically targets
HCV. Vertex is conducting a global Phase 2b clinical development program
for telaprevir consisting of three large clinical trials that are expected
to enroll approximately 1000 patients with HCV at clinical centers in the
United States and Europe. The U.S.-based PROVE 1 trial is fully enrolled
and ongoing. The PROVE 2 study is underway in Europe and is expected to
complete enrollment with approximately 320 patients within the next few
weeks. Also in the next few weeks, Vertex expects to initiate PROVE 3, a
clinical trial of telaprevir that will enroll more than 400
treatment-experienced patients. In clinical trials, telaprevir is being
dosed as 750 mg every eight hours in combination with pegylated interferon
alfa-2a (Pegasys(R)), both with and (in the PROVE 2 study) without
ribavirin (Copegus(R)).
