Merck secures approval, debuts new hepatitis C drug
SILVER SPRING, Md.—Merck's drug candidate Victrelis (boceprevir) secured U.S. Food and Drug Administration (FDA) approval this month, amking it the first hepatitis C drug to gain approval in 20 years. Victrelis is approved to treat adults with chronic hepatitis C who still retain some liver function and who have either failed previous drug therapy or have not undergone such treatment. The drug is approved for combined use with peginterferon alfa and ribavirin.
"Victrelis is an important new advance for patients with hepatitis C," says Edward Cox, M.D., director in the Office of Antimicrobial Products in the FDA's Center for Drug Evaluation and Research. "This new medication provides an effective treatment for a serious disease, and offers a greater chance of cure for some patients' hepatitis C infection compared to currently available therapy."
Victrelis' safety and effectiveness were evaluated in two Phase III clinical trials with 1,500 adult patients. In both trials, two-thirds of patients who received Victrelis together with pegylated interferon and ribavirin experienced a significantly increased sustained virologic response, meaning that the hepatitis C virus was not detected in the blood 24 weeks after treatment ended, compared to those who received pegylated interferon and ribavirin alone, which is the current method of treatment. A sustained virologic response after treatment is completed suggests that the HCV infection has been cured. A sustained virologic response can result in decreased complications of liver disease, decreased cirrhosis (scarring of the liver), decreased rates of liver cancer (hepatocellular carcinoma) and decreased mortality.
Victrelis is taken orally three times a day with food, and falls into the class of drugs known as protease inhibitors, as it works by binding to the hepatitis virus and preventing it from multiplying. The common side effects reported from those taking Victrelis include nausea, headache, fatigue, low red blood cell count (anemia) and taste distortion (dysgeusia).
Hepatitis C is a contagious liver disease that can vary in intensity from an illness that lasts for a few weeks after infection (acute hepatitis C virus infection) to a lifelong illness that constantly attacks the liver (chronic hepatitis C virus infection). According to the U.S. Centers for Disease Control and Prevention (CDC), acute infection will lead to chronic infection in approximately 75 to 85 percent of people who become infected with hepatitis C. The CDC notes that an estimated 3.2 million people in the U.S. have chronic hepatitis C, though numbers for this disease are difficult to pin down exactly since most people don't know they are infected since they do not feel sick. Many people with hepatitis don't display any symptoms until liver damage occurs, something that could take years. Hepatitis C is spread through the blood and can be transmitted by sharing needles with an infected person or being born to a mother with HCV. There is no vaccine for hepatitis C.
A majority of the liver transplants in the U.S. are required because of progressive liver disease caused by a hepatitis C infection. Some people suffering from chronic hepatitis C infection will develop cirrhosis, or scarring, of the liver after several years, which can lead to liver damage and complications such as jaundice, bleeding, infections, fluid accumulation in the abdomen or liver cancer.