View clinical trials related to Chronic Hepatitis B.
Filter by:The purpose of this clinical research study is to assess the safety effectiveness of entecavir, as compared to lamivudine, in the treatment of adults with chronic hepatitis B infection who are hepatitis B e antigen positive.
This study will evaluate the safety and effectiveness of adefovir plus lamivudine for chronic hepatitis B infection in people with and without HIV infection. Lamuvidine, an FDA-approved treatment for hepatitis B infection, also works against HIV. In some patients, the hepatitis B virus (HBV) continues to reproduce despite lamivudine treatment. Adefovir is an experimental drug that inhibits HBV replication and may work against some strains of the virus that have become resistant to lamivudine. Patients 21 years of age or older with active hepatitis B infection despite treatment with lamivudine for at least 1 year may be eligible for this 48-week study. Patients both with or without HIV infection may participate. Candidates will be screened with a medical history, blood and urine tests, liver ultrasound exam, electrocardiogram (EKG) and chest X-ray. Participants will have a physical examination, review of their medical history, blood tests, and a 24-hour urine collection. They will be admitted to the hospital for a liver biopsy to determine if they can receive the study drug. For this procedure, the patient is given a sedative for relaxation. The skin over the biopsy is numbed with an anesthetic and the biopsy needle is passed rapidly into and out of the liver to collect a tissue specimen. Patients are monitored in the hospital overnight for possible complications. After discharge, they return home and begin taking the study medications. Patients will be randomized to two treatment groups. One group will take 10 milligrams/day of adefovir by mouth, and the other will take a placebo-a lookalike pill with no active ingredient. Both groups will also take 150 mg lamivudine by mouth and L-carnitine pills or liquid. Patients with HIV infection will continue to take antiretroviral therapy as well. Patients will be followed in the clinic at study weeks 2, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40 and 44 for blood and urine tests to determine the safety of the drug and to evaluate the response to treatment. On week 48, a repeat 24-hour urine test and repeat liver biopsy will be done. At the end of the 48 weeks, patients may continue to receive adefovir for another 48 weeks and possibly longer. All those who participate in this extension phase will receive active adefovir, regardless of whether they had previously taken adefovir or placebo. All patients will have the option to enroll in a separate study to examine the levels of HBV (and levels of HIV in HIV-infected patients) in the blood immediately after starting treatment and to determine if these initial levels can predict later outcome. This involves seven additional visits, for which participants will be compensated. At these visits, blood will be drawn on study days 0 (before starting drug treatment), 1, 3, 5, 7, 10 and 21 for HIV and HBV viral loads and specialized immunology tests.
Chronic hepatitis B is a disease of the liver caused by the hepatitis B virus. It affects nearly 1 million Americans. Approximately 25% of patients with chronic hepatitis B will develop liver cirrhosis and 5% of patients will develop liver cancer. Presently, two medications have been shown effective in the treatment of hepatitis B: lamivudine and alpha interferon. Alpha interferon (an antiviral drug that acts through the immune system) is given by injection once daily or three times a week for four to six months. Lamivudine (also known as 3-thiacytidine: 3TC) is an antiviral medication given as a pill once a day for twelve months. These treatments have been known to provide long-term improvement in one third of patients receiving them. In previous research, the drug lamivudine was shown to stop the growth of the hepatitis B virus and to lead marked decreases in the levels of hepatitis B virus and to improvements in the disease in 50 to 70% of patients. However, once lamivudine therapy was discontinued the virus returned to levels noted before the therapy began. In those studies lamivudine was given for 3 to 12 months then discontinued. This study will investigate the safety and effectiveness of long-term therapy with lamivudine. This study will select 60 patients diagnosed with hepatitis B. After a thorough medical examination and liver biopsy, subjects will be given lamivudine. The drug will be taken by mouth in tablet form (100 mg) once a day for up to 5 years. Subjects will undergo regular check-ups and after 1 year of therapy be admitted to the Clinical Center for another medical examination and liver biopsy to assess progress. Patients who have benefitted from the therapy will continue taking the medication for up to 5 years. A third liver biopsy will be done during the last year of treatment. The effectiveness of lamivudine will be determined by whether levels of hepatitis B virus decrease in the blood, whether liver enzymes improve, and whether inflammation and scarring decreases in the liver biopsies.