Once-Daily
BI201335 Ups Response to Interferon for Hepatitis C
SUMMARY:
Boerhinger Ingelheim's experimental HCV protease inhibitor
BI201335 added to pegylated interferon and ribavirin improved
sustained response rates for both treatment-naive and treatment-experienced
genotype 1 patients, researchers reported at EASL 2011. |
By
Liz Highleyman
Direct-acting antiviral agents that target various steps of
the hepatitis C virus (HCV) lifestyle are expected to bring
about a new paradigm in treatment for chronic
hepatitis C, especially for patients with hard-to-treat
HCV genotype 1. To date, most experimental drug candidates have
been added to standard therapy consisting of pegylated
interferon (Pegasys or PegIntron) plus ribavirin, but investigators
have started to look at all-oral regimens.
At
the European Association for the Study of the Liver's International
Liver Congress (EASL 2011) this month
in Berlin, researchers presented results from SILEN-C1 and SILEN-C2,
which evaluated the NS3/4A protease inhibitor BI201335
in people starting treatment for the first time and in those
who did not respond to prior therapy, respectively.
SILEN-C1:
Treatment-naive
The Phase 2b SILEN-C1 trial included 429 chronic hepatitis C
patients with HCV genotype 1 who had not received prior interferon-based
therapy. Just over half were men, more than 80% were white,
and the average age was about 45 years.
Participants were randomly allocated into 4 arms. The first
2 arms added either 120 mg or 240 mg once-daily BI201335 after
a 3-day lead-in period taking pegylated interferon alfa-2a (Pegasys)
plus weight-adjusted ribavirin. The third group started 240
mg once-daily BI201335 and pegylated interferon/ribavirin at
the same time with no lead-in. The final control group received
standard therapy consisting of pegylated interferon/ribavirin
plus placebo.
All groups received BI201335 for 24 weeks. The 120 mg BI201335
and placebo groups then continued pegylated interferon/ribavirin
through week 48. Patients in the 240 mg BI201335 arms who had
an extended rapid virological response (eRVR; HCV viral load
< 25 IU/mL at week 4 and weeks 8-20) were randomized again
to either stop all therapy at week 24 or continue interferon/ribavirin
through week 48.
Results
 |
All
groups receiving BI201335 had significantly better response
than those receiving standard therapy plus placebo. |
 |
The
highest rapid and sustained virological response (SVR) rates
were seen in participants who received 240 mg once-daily
BI201335 without the lead-in. |
|
 |
Extended
RVR: |
|
 |
240
mg BI201335 without lead-in: 87%; |
 |
240
mg BI201335 with lead-in: 78%; |
 |
120
mg BI201335 with lead-in: 80%; |
 |
Standard
therapy: 16%. |
|
 |
SVR: |
|
 |
240
mg BI201335 without lead-in: 83%; |
 |
240
mg BI201335 with lead-in: 73%; |
 |
120
mg BI201335 with lead-in: 71%; |
 |
Standard
therapy: 56%. |
|
|
 |
Among
participants in the 240 mg BI201335 arms randomized to different
treatment durations, response rates were as follows: |
|
 |
240
mg with lead-in: 82% for 24 weeks vs 96% for 48 weeks,
a significant difference; |
 |
240
mg without lead-in: 93% for 24 weeks vs 90% for 48
weeks, not significant; |
|
 |
Relapse
rates were about 8% in the 240 mg BI201335 without lead-in
arm vs 14% in the standard therapy arm. |
 |
Overall adverse event rates were higher in the BI201335
arms, though most were mild to moderate. |
 |
Severe
adverse event rates were 12% and 16% in the 120 mg and 240
mg BI201335 with lead-in arms and 13% in the 240 mg BI201335
without lead-in arm, compared with 4% in the standard therapy
arm. |
 |
Rates
of discontinuation due to adverse events were 4%, 12%, 5%,
and 1%, respectively. |
 |
Patients
taking BI201355, especially the 240 mg dose, were more likely
to experience nausea and vomiting. |
 |
About
20% of patients taking the higher BI201335 dose developed
jaundice, compared with about 1% in the control arm; there
were no severe cases. |
 |
Patients
taking the higher BI201335 dose were more likely to experience
skin rash, including moderate and severe (about 4%) rash. |
 |
Mean
ALT levels improved in all BI201335 arms compared with placebo. |
The
investigators concluded that BI201335 once-daily with pegylated
interferon/ribavirin "achieved high efficacy with good
tolerability and safety at all dose levels."
In the 240 mg BI201335 without lead-in arm, 87% achieved SVR,
and continuing pegyalted interferon/ribavirin for an additional
24 weeks did not improve outcomes. The 3-day pegyalted interferon/ribavirin
lead-in was associated with reduced response rates and more
adverse events.
SILEN-C2:
Treatment-experienced
The Phase 2b SILEN-C2 study looked at the efficacy of BI201335
among genotype 1 chronic hepatitis C patients who did not respond
to a prior course of at least 12 weeks of pegyalted interferon/ribavirin.
This study included 288 participants. About two-thirds were
men, about 90% were white, and the mean age was about 50 years.
About half were prior null responders -- meaning they never
had a substantial (at least 1 log) decrease in HCV RNA during
treatment -- and about one-third were prior partial responders
(more than 1 log decrease, but never undetectable); prior relapsers
were not included.
Participants were randomly assigned to receive 240 mg BI201355
either once or twice daily, and if once-daily, with or without
a 3-day pegylated interferon/ribavirin lead-in period. Again,
everyone stopped BI201335 at week 24. The 240 mg once-daily
lead-in group was further randomized to stop pegylated interferon/ribavirin
at the same time or continue through week 48.
Results
 |
The
arms with and without the lead-in had similar extended RVR
rates, but the once-daily arm without lead-in pulled ahead
for SVR. |
 |
Extended
RVR rates were as follows: |
|
 |
240
mg BI201335 twice-daily with lead-in: 47%; |
 |
240
mg BI201335 once-daily with lead-in: 43%; |
 |
240
mg BI201335 once-daily without lead-in: 45%; |
|
 |
SVR
rates were as follows: |
 |
240
mg BI201335 twice-daily with lead-in: 31%; |
 |
240
mg BI201335 once-daily with lead-in: 27%; |
 |
240
mg BI201335 once-daily without lead-in: 41%; |
|
 |
50%
of prior partial responders and 35% of null responders achieved
SVR in the once-daily without lead-in arm. |
 |
Among
patients in the once-daily with lead-in group, those treated
for 48 weeks had a significantly higher SVR rate than those
treated for 24 weeks (72% vs 40%, respectively). |
 |
Participants
receiving twice-daily BI201335 had about double the rate
of severe adverse events compared with once-daily recipients
(28% vs 14%, respectively). |
 |
About
15% of patients in the twice-daily lead-in arm, but only
1% in the once-daily without lead-in arm, discontinued due
to adverse events. |
 |
About
6% of patients in the twice-daily lead-in arm experienced
severe skin rash vs 1% in the once-daily without lead-in
arm. |
 |
There
were no cases of severe jaundice in any arm. |
The
investigators concluded that 240 mg BI201335 given once-daily
with pegylated interferon/ribavirin "showed high efficacy
and good tolerability in this very difficult-to-treat patient
population with non-response to previous [pegylated interferon/ribavirin]
therapy."
Again, the 3-day pegylated interferon/ribavirin lead-in was
associated with decreased virological response. In contrast
with the treatment-naive patients in SILEN-C1, however, prior
non-responders did significantly better with 48 weeks compared
with 24 total weeks of treatment.
Investigator affiliations:
SILEN-C1: Johns Hopkins University, Baltimore, MD; Dr. Victor
Babes Hospital for Infectious and Tropical Diseases, Bucharest,
Romania; Hôpital Beaujon, Clichy Cedex, France; Prof.
Dr. Matei Bals Institute of Infectious Diseases, Bucharest,
Romania; Quest Clinical Research, San Francisco, CA; Medical
University of Vienna, Vienna, Austria; Hospital Francisco J.
Muniz, Uspallata, Arhentina; Hospital Provincial Del Centenario,
Rosario, Argentina; Royal Brisbane & Women's Hospital, Brisbane,
Queensland, Australia; Instituto CAICI, Rosario, Argentina;
Center for HIV and Hepatogastroenterology, Düsseldorf,
Germany; Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT;
Boehringer Ingelheim Pharma, Biberach, Germany.
SILEN-C2: Johns Hopkins University, Baltimore, MD; Hôpital
Saint Joseph, Marseille, France; Hôpital de Brabois, Vandoeuvre
Cedex, France; Prof. Dr. Matei Bals Institute of Infectious
Diseases, Bucharest, Romania; Hôpital Beaujon, Clichy,
France; Hôpital Henri Mondor, Créteil, France;
University of Alberta, Edmonton, Alberta, Canada; Hôpital
Cochin, Paris, France; Center for HIV and Hepatogastroenterology,
Düsseldorf, Germany; Hôpital Saint-Eloi, Montpellier,
France; Boehringer Ingelheim Pharma, Biberach, Germany; Boehringer
Ingelheim Pharmaceuticals, Ridgefield, CT.
4/15/11
References
M Sulkowski, E Ceasu, T Asselah, et al. SILEN-C1: Sustained
Virologic Response (SVR) and safety of BI201335 combined with
peginterferon alfa-2a and ribavirin (P/R) in treatment-naive
patients with chronic genotype 1 HCV infection. 46th Annual
Meeting of the European Association for the Study of the Liver
(EASL 2011). Berlin. March 30-April 3. Abstract
60/324.
M Sulkowski, M Bourliere, J-P Bronowicki, et al. SILEN-C2: Sustained
Virologic Response (SVR) and safety of BI201335 combined with
peginterferon alfa-2a and ribavirin (P/R) in chronic HCV genotype-1
patients with non-response to P/R. 46th Annual Meeting of the
European Association for the Study of the Liver (EASL 2011).
Berlin. March 30-April 3. Abstract
66/330.
Other Source
Boehringer-Ingelheim. Positive Phase 2 results reported with
Boehringer Ingelheim's investigational HCV protease inhibitor
in both previously treated and untreated patients. Press release.
April 1, 2011.