Victrelis (boceprevir), the first licenced medication to directly target the hepatitis virus was launched today in the United Kingdom. Victrelis is said to help clear the virus in nearly three times as many patients who did not respond properly to prior treatment, and nearly twice as many treatment naïve patients, compared to just current therapy.
Victrelis is for adult patients suffering from chronic hepatitis C (CHC) genotype 1 infection. It has been approved for use alongside standard therapy - peginterferon alfa and ribavirin. It is indicated for patients with compensated liver disease who either did not respond to previous therapy, or have not yet been treated (treatment naïve).
Clinical trials reported that:
- Adding boceprevir to standard therapy multiplied by 2.8 the number of patients who achieved SVR (sustained virologic response, i.e. cleared the virus), compared to those who were on just standard therapy.
- In treatment naïve patients (never been treated before), adding boceprevir multiplied by 1.7 the number of patients achieving SVR, compared to those on just standard treatment.
Dr Ashley Brown, Consultant Hepatologist of St Mary's & Hammersmith Hospitals, said:
"Over the last 10 years there has been little development in the treatment of HCV and a significant proportion of patients fail to respond to current standard of care. 'Victrelis' is the first licensed drug to directly target the virus. It offers improved outcomes for genotype 1 patients and new hope for those in whom previous treatment has been unsuccessful."
Approximately one-quarter of a million individuals in the UK are chronically infected with hepatitis C. Diagnosis is commonly delayed because a considerable number of people are infected for a long time before they experience any symptoms. Hence, it is sometimes called the silent epidemic. An average GP (general practitioner, primary care physician) with a list of 1,800 patients will typically have between 8 and 20 patients with hepatitis C infection.
Hepatitis C, caused by a blood-borne virus, can eventually lead to liver inflammation and scarring (fibrosis) of liver tissue. It can eventually progress to cirrhosis and liver cancer.
There are different genotypes (strains) of the virus. In the UK, genotype 1 affects between 40% and 50% of infected individuals. Genotype 1 is also the hardest to clear, with a 40% SVR rate on current treatment. SVR rates for genotypes 2, 3 and 9 are about 80%.
Two pivotal Phase III studies - known as HCV RESPOND-2 and HCV SPRINT-2 - investigated adding boceprevir to standard therapy. They included 403 patients who had not responded to prior therapy and 1,097 who had never been treated. Both studies included a response guided therapy arm which looked at shortened treatment duration. Some of the previously untreated patients could have stopped at 28 weeks, rather than the 48 weeks of standard therapy alone.
Boceprevir interferes with the hepatitis C virus' ability to replicate. It inhibits a key viral enzyme. Current standard therapy works by boosting the patient's immune system to elicit a response.
The most common adverse events linked to boceprevir included anemia, dysgeusia (metallic taste), headache, nausea, and fatigue. Side effects, when they do occur are said to be manageable.
Written by Christian Nordqvist