The Food and Drug Administration (FDA) on Monday approved the second drug in two weeks for the treatment of hepatitis C. The new drug, called Incivek, is designed to be used in conjunction with standard therapy with interferon and ribavirin.
Incivek (telaprevir) works the same way as Merck & Co’s Victrelis (boceprevir), which was approved by the FDA on May 13. The two competing drugs are the first new treatments for hepatitis C in two decades. Both block the replication of an enzyme that is crucial for the hepatitis C virus to reproduce. While the virus would quickly become resistant to either drug used alone, the drugs are successful when combined with standard interferon/ribavirin treatment, WebMD reports.
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In trials, both drugs increased patients’ chances of being cured, or achieving “sustained virologic response”; although the virus itself cannot be completely eliminated, a sustained virologic response means that the virus is no longer detectable in the blood and that the chances of complications from hepatitis C disease (including cirrhosis and liver cancer) are eliminated.
Incivek, marketed by Vertex Pharmaceuticals, was approved based on results of clinical trials that involved more than 2,000 adults. The patients were treated with a combination of Incivek and standard therapies for 12 weeks; typical interferon-only therapy lasts 48 weeks. Adding Incivek produced a sustained viral response in 79% of previously untreated patients, a 45% higher rate of cure than in the standard-care only group.
When including all patients — those who had and had not been previously treated for hepatitis C — sustained virologic response for patients treated with Incivek was between 20% and 45% higher than those receiving standard of care.
Sustained virologic response was also achieved faster with Incivek, and 60% of previously untreated patients were able to stop treatment after 24 weeks, compared with 48 weeks for those on the traditional treatment.
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“With the approval of Incivek, there are now two important new treatment options for hepatitis C that offer a greater chance at a cure for some patients with this serious condition,” said Edward Cox, FDA’s director of antimicrobial products, in a statement. “The availability of new therapies that significantly increase responses while potentially decreasing the overall duration of treatment is a major step forward in the battle against chronic hepatitis C infection.”
An estimated 3.2 million Americans are infected with hepatitis C, according to the Centers for Disease Control and Prevention. The virus, which can be transmitted through blood or sex, causes liver inflammation that can lead to liver failure.
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Incivek should be given for the first 12 weeks of combination treatment and taken three times a day with food. The most common side effects reported by patients included rash, anemia, nausea, fatigue, headache, diarrhea, itching, and anal or rectal irritation and pain.
Reuters reports that the approval of this “highly anticipated” drug sets up a ”head-to-head marketing battle” with Merck & Co. in a profitable market. Some analysts predict that Incivek’s sales will top $5 billion a year.