Withdrawal of Therapy After Long-Term Antiviral Treatment for Chronic Hepatitis B

Background: \- Chronic infection with the hepatitis B virus may lead to cirrhosis, liver disease, and cancer of the liver. There is no cure for the infection, but several drugs have been approved to treat it. These drugs can keep the virus levels low. They seem to be safe for short-term use. But the drugs have not yet been approved for long-term use because some of them can have serious side effects. However, stopping treatment too soon can make the infection worse and may lead to more serious forms of liver disease. Researchers have not been able to determine a when to stop treatment. They want to study people with chronic hepatitis B infection to find out the best time to stop treatment and prevent the disease from causing further liver damage. Objectives:

• To study the safety and effectiveness of withdrawing antiviral treatment for chronic hepatitis B after at least 4 years of treatment.
• To determine whether stopping long-term antiviral treatment for chronic hepatitis B makes the infection worse. Eligibility: \- People who are at least 18 years of age; have been taking antiviral drugs to treat chronic hepatitis B for at least 4 years; and are being evaluated to stop treatment. Design:
• Those in the study will be screened with a physical exam, medical history, questionnaire, and blood tests. They will remain under the care of their regular doctor during the study.
• They will have an abdominal ultrasound to study scarring in the liver, if they have not had one in the past year.
• Those without detectable levels of the hepatitis B virus in their blood will stop antiviral treatment. They will have monthly blood tests for the first 6 months to check virus levels, and then every 3 months afterward.
• Those whose blood tests show an increase in virus levels will restart antiviral treatment as directed by the study doctors and their personal doctor.
• All those in the study will be monitored until the end of the study.