View clinical trials related to Hepatitis B.
Filter by: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.
The purpose of this study is to determine if 2 doses of Pneumococcal Conjugate Vaccine (PCV) followed by 1 dose of Pneumococcal Polysaccharide Vaccine (PPV) in HIV-infected children on anti-HIV therapy is helpful and safe in fighting pneumococcal infections in this group of children. This study will also look at the protection provided by childhood vaccination against measles, pertussis, and hepatitis B virus. Pneumococcal infections are the most common AIDS-related infection in HIV-infected children. PCV may help reduce the chances of HIV-infected children getting pneumococcal infections. This study will look at whether pneumococcal vaccines are safe and effective in HIV-infected children receiving HAART. It will look at whether HIV-infected children are protected by childhood vaccines received previously and if more doses are safe and improve protection.
This study will evaluate the safety and effectiveness of adding the experimental drug adefovir dipivoxil to lamivudine for treating hepatitis B virus (HBV) infection in HIV-infected patients with liver cirrhosis. Adefovir inhibits HBV by interfering with replication of the virus's genetic material. In some people, the drug has been active against strains of HBV that are resistant to lamivudine; it may also have some activity against HIV. HIV-infected patients 21 years of age and older with chronic hepatitis B infection and liver cirrhosis who have received lamivudine treatment for at least 1 year may be eligible for this 48-week study. Candidates will be screened with a complete medical history, blood tests and a 24-hour urine collection. Blood tests include HLA typing (a test of genetic markers on white blood cells that permit specialized immunology studies). Within 4 weeks, candidates who appear eligible for the study will have a physical examination and medical history, an abdominal ultrasound (imaging test using sound waves) to check for cancer of the liver, chest X-ray and electrocardiogram (EKG). Blood and urine tests will also be done, and women who can become pregnant will have a pregnancy test. Patients who meet the study criteria and decide to participate will then start treatment with one 10-mg adefovir pill per day by mouth. In addition, patients will continue to take all other medications prescribed by their doctor. Follow-up clinic visits will be scheduled as follows: - Days 1, 3, 5, 7, 10 and 21 - Blood will be drawn for specialized immunology tests and to measure blood levels of HIV and HBV. - Weeks 2, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 - Blood and urine (single sample) tests will be done to determine the side effects of adefovir and its effect on the HBV infection. - Week 48 or early termination (end of study) - Blood tests (including tests for hepatitis C and D), abdominal ultrasound and a 24-hour urine collection to evaluate kidney function will be done. - Monthly visits beyond week 48 - Based on the HBV response to treatment and the availability of the drug from the sponsor, patients may be offered to extend their treatment with adefovir. Those who continue will have monthly follow-up visits for blood and urine (single sample) tests.
This study will evaluate hepatitis C virus (HCV) infection in blood donors who test positive for antibodies to this virus. Most HCV-infected people do not become ill and are not aware that they have hepatitis or have had it in the past. Some infected people recover completely, whereas others remain chronically infected. The study will try to define infectivity of anti-HCV positive individuals, routes of transmission of the virus, and the number of HCV-infected persons who have evidence of liver disease. Blood donors at the NIH Clinical Center or the Central Maryland Chapter of the American Red Cross who test positive for HCV may be eligible for this study. Participants will have a physical examination and history, including questions about socioeconomic status and current sexual practices. They will have 100 milliliters (ml) (6 tablespoons) of blood drawn at the first visit and 50 ml (3 tablespoons) drawn 3, 6, 9 and 12 months after the initial visit. Some participants may undergo plasmapheresis, a procedure for collecting additional plasma (the liquid portion of the blood). For this procedure, whole blood is collected through a needle placed in an arm vein. The blood circulates through a machine that separates it into its components. The plasma is then removed, and the red and white cells and platelets are returned to the body, either through the same needle used to draw the blood or through a second needle placed in the other arm. In some individuals, other body fluids (saliva, urine or semen) may also be collected. Participants may be asked to bring their household contacts and sexual partners to NIH for interview and blood testing for evidence of HCV infection and liver disease. Although this is not required for participation in the study, it would provide additional valuable information. Participants found to have chronic viral infection will be seen more often and will provide additional blood samples for routine medical care. Further medical evaluation may include X-rays or liver scans and referral to a specialist for additional tests or therapy. Ten people in this study will be recruited to participate in a secondary investigation to analyze changes in the level of HCV and the immune response to it, and to relate these changes to the degree of liver damage. In addition to blood collected for the primary study, participants in this investigation will have an additional 50 ml (3 tablespoons) of blood drawn from an arm vein every week for 10 weeks to measure levels of virus, ALT (a liver enzyme), and immune response.
Following guidelines issued by the Centers for Disease Control, the Clinical Center implemented a Universal Precautions policy in November 1987 in an attempt to reduce healthcare workers' risks for occupational exposures to bloodborne pathogens. All hospital personnel whose jobs entailed potential exposure to patients' blood and body substances were required to attend a training session and complete a written examination. Based on data from surveys conducted before and twelve months after training in Universal Precautions, the frequency of cutaneous exposure to blood decreased by 50% in temporal association with implementation of Universal Precautions. Staff at the Clinical Center are required to take a refresher course in Universal Precautions annually. The prevalence of bloodborne infections is high in Japan; however, Universal Precautions are not widely practiced in Japan. This study is designed: 1) to evaluate and compare nurses' knowledge of the epidemiology, pathogenesis, occupational risks, and appropriate prevention strategies for managing patients infected with bloodborne pathogens in the healthcare setting in seven university hospitals in Japan and at the Clinical Center of the National Institutes of Health in the US; 2) to compare self-reported levels of compliance with existing infection control recommendations designed to limit risk for exposure to bloodborne pathogens in all four institutions; 3) to compare self-reported frequencies of cutaneous exposures to blood at the four hospitals in the study; and 4) to evaluate the effect of educational intervention on nurses perceived compliance with recommendations and on the frequency of self-reported exposures to blood.
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.
To determine the tolerance of HIV-infected patients to TID oral doses of FIAU syrup at 4 different dose levels. To determine the peak and trough blood levels of FIAU and its metabolites during two weeks of oral dosing with FIAU. The pyrimidine nucleoside analog FIAC and its primary deaminated uracil metabolite FIAU are highly and specifically active compounds in vitro against several herpes group viruses, particularly herpes simplex virus (HSV) types 1 and 2, varicella zoster (VZV), and cytomegalovirus (CMV), as well as hepatitis B virus (HBV). Since FIAU is the primary metabolite of FIAC and the administration of FIAU simplifies the metabolism of FIAC, it is anticipated from clinical studies of FIAC that FIAU will be tolerated at least as well as FIAC. A single-dose, pharmacokinetic (blood level) study showed that FIAC, when taken orally, is readily absorbed into the bloodstream, and most of it is converted to FIAU. Daily oral doses are expected to provide concentrations of FIAU exceeding the in vitro minimum inhibitory concentration for nearly all the herpes group viruses.
To determine the efficacy of a hepatitis vaccine in preventing hepatitis B.
To evaluate whether hepatitis B immune globulin with a high level of antibody against the hepatitis B antigen would be capable of interrupting maternal-fetal transmission of hepatitis B virus, the single most important route of hepatitis spread in the entire Third World.