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New treatments for Hepatitis C |
Treatment for chronic Hepatitis C
from the Hepatitis C Council of Australia
Until recently the treatment for chronic hepatitis C has been standard
interferon alone or standard interferon combined with ribavirin. People
treated have responded differently to these treatment regimes. A number of
factors influence response rates.
People more likely to respond are those who
- have genotype 2 or 3 of the virus
- have lower levels of virus in their blood (viral load) before they start
- treatment
- are 40 years old or younger
- became infected with hepatitis C at a younger age
- are female
- have less liver scarring (fibrosis) on liver biopsy
What is Interferon
Interferons are small proteins made by the body to help fight infections such as those caused by viruses. The body produces different types of interferon in
response to different infections.
Treatments for Hepatitis C
The standard interferon used to treat hepatitis C is a synthetic copy of the
interferons naturally produced by the body in response to infection. It is given as an injection under the skin up to three times a week.
Pegylated Interferon
Pegylated interferon is an altered form of interferon recently developed and
now available for use in certain circumstances, primarily when a person cannot
tolerate the ribavirin component of combination therapy. A chemical called
polyethylene glycol (PEG) is attached to interferon, which prolongs the effect of the drug in the body. There are two reasons for this
- PEG protects the interferon molecule from the normal de-activation processes of the body the size of PEG-interferon is larger than standard interferon, which means it stays longer in the circulation
There are two types of pegylated interferon, made by different drug companies
- PegIntron alpha 2b is made by Schering-Plough
- PEG Interferon alpha 2a is made by Roche
Both of these pegylated interferons are given once a week, as a subcutaneous
(under the skin) injection.
How do we know if treatmentis effective
Currently successful treatment for hepatitis C is considered to be treatment that results in a sustained viral response (SVR). A sustained viral response is when there is no detectable hepatitis RNA in a person's blood 6 months after stopping treatment. Medical researchers are cautious about calling this a “cure”. However, recent research in which people have been followed for 4 years after successful treatment suggests that a relapse is unlikely once viral clearance has been maintained for six months
Non Responce or Relapse following Treatment
Relapsers' are described as people who have a good response to treatment
during therapy, but within six months of stopping treatment the virus can be
detected again in their blood.
`Non-responders' are those who do not response to treatment, in that the virus is still detectable in the blood and the liver function tests (particularly
for ALT) are abnormal. Combination therapy with pegylated interferon and
ribavirin may result in a higher response rate for these people.
Pegylated Interferon Therapyas a monotherapy
The effectiveness of both types of pegylated interferon as a monotherapy (by them selves) has been studied, and the results are similar. Treatment for 48 weeks resulted in a doubling of sustained response rates compared with standard interferon. However, relapse rates were the same as with regular interferon. People with genotype 1 did not respond any better to therapy with pegylated interferon. It seems that pegylated interferon alone will not replace the use of interferon ribavirin combination therapy.
Combination Pegylate Interferon and Riboviron
When pegylated interferon and ribavirin are combined the results are more
positive, especially for people with genotype 1.
Treatments for Hepatitis C The Future
Clarifying effective treatment regimes for hepatitis C remains a high priority on the research agenda. While much of the research is focused on combination
therapies using interferon and ribavirin, some people are unable to tolerate hese medications. Other drugs and treatment regimes that may be more effective and have fewer side effects are being assessed. This research is at varying stages of development.
more.
Hepatitis C council of Australia
the Australian Hepatitis Council
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