(brand name Victrelis) is a new
medication used to treat hepatitis C. It was approved in Europe
in July 2011 for treatment of adults with genotype 1 chronic hepatitis C in
combination with pegylated interferon and ribavirin.
triple therapy cures about two-thirds of people who take it, but it works
better for some groups than others. Successful treatment reduces the risk of
long-term complications of hepatitis C such as liver cancer or needing a liver
Boceprevir is no longer available in the United States. Boceprevir
is still licensed in the European Union but is no longer recommended as an
appropriate treatment for hepatitis C by the European Association for the Study
of the Liver, owing to a higher rate of side-effects and a lower cure rate when
compared to newer interferon-free treatments licensed since 2014.
How does boceprevir work?
Boceprevir is one of
the new direct-acting antiviral drugs that target different steps of the
hepatitis C virus (HCV) lifecycle. It is an HCV protease inhibitor, meaning it
blocks the protease enzyme which the virus must use to reproduce. Boceprevir
must be used with two older drugs: pegylated interferon, which stimulates the
body's own immune response against the virus, and ribavirin, which improves the
effectiveness of interferon.
Who can use boceprevir?
indicated for use by adults with chronic hepatitis C, meaning infection lasting
more than six months. It is approved for people with HCV genotype 1, which is
the most common type in Europe and considered the hardest to treat. It is not
approved and should not be used to treat other HCV genotypes.
Boceprevir can be used
by people being treated for hepatitis C for the first time (known as
'treatment-naive') and for retreatment of people who were not cured with
previous interferon-based therapy.
Boceprevir has also
been tested in people with HIV and HCV co-infection. Response rates and side-effects
are similar to those of HIV-negative people. However, boceprevir should not be
used with certain HIV medications due to drug interactions. People with HIV and HCV
co-infection who want to take boceprevir should do so under the care of a doctor
who has experience treating both infections.
Boceprevir can be used
by people with all stages of compensated liver disease including cirrhosis, but
it works better for people with less advanced liver damage. Also, people with
cirrhosis who take boceprevir may experience more serious side-effects.
Boceprevir triple therapy can be dangerous and therefore should not be used by
people with decompensated liver disease, or liver failure.
How is boceprevir taken?
Boceprevir is taken as
four capsules three times daily with a light meal or snack. It must be used
with weekly pegylated interferon injections and twice-daily ribavirin pills.
Boceprevir is not effective if taken alone, and this can lead to drug resistance.
Treatment starts with
a 'lead-in' period of pegylated interferon and ribavirin taken alone for 4
weeks. Then boceprevir plus pegylated
interferon and ribavirin are taken together as triple therapy for 24 to 44
additional weeks. Some people will then continue on pegylated interferon/ribavirin
alone for several more weeks. Treatment duration will depend on early response,
previous treatment history and extent of liver damage. This is known as
How effective is boceprevir?
works better for some people than for others. Several factors predict how well
someone will respond. Boceprevir is only approved for genotype 1 hepatitis C.
It is not effective for other genotypes including 2, 3 or 4. Different
direct-acting antivirals work better against these other genotypes.
One of the most
important factors is previous treatment history. People who are new to
treatment, and those who relapsed after finishing previous treatment, have the
best chance of being cured with boceprevir. Boceprevir triple therapy does not
work as well for people who had only a partial response or no response to prior
- Sustained responder: a person who was successfully treated and
cured of hepatitis C.
- Relapser: a person who reached undetectable HCV viral load with previous
interferon-based therapy, but relapsed, or saw the virus return, after
- Partial responder: a person who had some decrease in HCV viral
load with previous treatment, but did not reach an undetectable level.
- Null responder: a person who had little or no decrease in HCV
viral load with previous treatment.
People with less
advanced liver damage respond better to treatment. People with cirrhosis are
less likely to be cured with boceprevir triple therapy and they may have more
problems with drug side-effects.
Because they are more
difficult to treat, previous null responders and people with cirrhosis should
receive boceprevir triple therapy for a full 44 weeks if they can tolerate the
Boceprevir treatment response
People who experience
a rapid drop in HCV viral load soon after starting treatment are more likely to
be cured. Undetectable viral load at week 8 and week 24 of boceprevir triple
therapy is a good predictor of who will be cured. This will make some patients
eligible for shorter treatment. But people who do not respond well after the
first 12 or 24 weeks should stop treatment, as it is unlikely to work if
People with sustained
virological response, who still have undetectable viral load at 12 or 24 weeks
after finishing treatment (known as 'SVR12' or 'SVR24'), are considered cured.
A clinical study
called SPRINT-2 tested boceprevir triple therapy in previously untreated patients.
Up to 66% of people who took boceprevir were cured, compared with 38% of those
who took only pegylated interferon and ribavirin.
Another study called
RESPOND-2 tested boceprevir triple therapy in previously treated people. Up to
75% of prior relapsers who took boceprevir were cured, compared with 29% who
took only pegylated interferon and ribavirin. The boceprevir sustained response
rate was lower for previous partial responders (up to 52%). This trial did not include previous null responders, but another study
showed they had a cure rate of about 40%.
Boceprevir has also
been tested in people with HIV and HCV co-infection, showing response rates and
side-effects similar to those of people with hepatitis C alone. In one study, 61%
of previously untreated patients with co-infection who took boceprevir triple therapy
were cured, compared with 27% who took only pegylated interferon and ribavirin.
effectiveness in 'real world' use is somewhat lower than cure rates seen in
clinical trials, in part because patients may be sicker or have other
conditions that can make treatment more complicated.
therapy has been tested in people with advanced liver disease, including people
who are awaiting or have received liver transplants. Sustained response rates
are higher than those of pegylated interferon/ribavirin alone, but people with
advanced disease often have trouble tolerating treatment side-effects.
What are the side-effects of boceprevir?
Boceprevir causes some
side-effects of its own, but many symptoms in people taking triple therapy are
due to pegylated interferon or ribavirin. The most common side-effects of
boceprevir are anaemia (low haemoglobin level), nausea, fatigue, headache and
unusual taste sensations (known as 'dysgeusia'). Anaemia is the most likely
serious side-effect. Some people also develop neutropenia (low white blood cell
interferon include headache, fatigue, muscle and joint aches and depression.
Ribavirin also causes anaemia, which can be worse when combined with
boceprevir. Ribavirin can cause birth defects and should not be used by
pregnant women or their male partners.
Does boceprevir interact with other drugs?
interact with other drugs that are processed by the same enzymes in the liver.
These include some antiretroviral drugs for HIV, heart disease drugs and
psychiatric medications. Sometimes drug doses can be adjusted to overcome these
interactions, but some medications should not be used together with boceprevir.
Information about specific drug interactions is available online at www.hep-druginteractions.org.
How can I get boceprevir?
available by prescription in European Union countries to treat genotype 1
hepatitis C. Ask your GP or liver specialist if boceprevir combination therapy
may be a good option.
When to start
treatment will depend on a number of factors, including severity of liver
damage (as determined by FibroScan or
a liver biopsy). People with mild liver disease may be able to wait, and new
more effective and better-tolerated hepatitis C medications that can be used
without interferon are coming soon. However, the decision to wait must take
into account how fast your liver disease might progress – which is hard to predict – and how soon new treatments will be approved
in your country.