View clinical trials related to Cytomegalovirus Infections.
Filter by:Objectives of this trial are to: Evaluate the kinetics and magnitude of the CMV-specific immune response post-Towne challenge (3000 pfu) in healthy CMV-seronegative volunteers who receive VCL CT02 administered (1 mg weekly x 3) 3 months previously compared to randomized controls who do not receive VCL CT02 as measured by: 1. antibody titers for gB; 2. T-cell IFN-g ELISPOT; 3. T-cell proliferation assays for IE1, pp65, and/or gB; and 4. cytokine and phenotypic flow cytometry responses to pp65, IE1, and/or gB. Evaluate the safety safety of Towne challenge in healthy CMV-seronegative adult subjects who have previously been immunized with a trivalent pDNA CMV vaccine (VCL-CT02) administered intramuscularly. Our hypothesis is that the immune response to Towne vaccine 3000 pfu challenge after VLC-CT02 priming will be greater than that after Towne vaccination alone.
Study Phase: IV Study Type: Open-label, multicenter, randomised clinical trial with two arms stratified for an intensified immunosuppressive regimen in patients at high risk for acute rejection. Study Description: 148 kidney transplant recipients at risk for CMV disease were randomized and treated with ganciclovir capsules for 3 months (Group A, prophylaxis, N=74) or received ganciclovir IV only in case of proven CMV viral load (Group B, preemptive therapy, N=74). Initially, a 2 months follow up was planned in this trial. However, the study group decided to offer a longterm follow up to all patients and amended the protocol, respectively. The aim of the study was to identify the most efficacious way to prevent renal transplant recipients from CMV disease and to find out, if one of these two strategies may increase graft or patient survival. Therefore, both wellknown approaches of CMV prevention were compared in two study groups: Prophylaxis (Group A): Oral primary prophylaxis with ganciclovir capsules was started directly after transplantation and performed until day 90. In case of CMV infection (proven CMV viral load) or symptomatic CMV disease, treatment with ganciclovir IV was initiated. Preemptive Therapy (Group B): No oral primary prophylaxis was given. Treatment with ganciclovir IV was given to patients with proven CMV viral load (CMV infection or CMV disease) only.
This 2 arm study will compare the efficacy of 100 days of Valcyte (900mg po daily) prophylaxis with that of no prophylaxis, under the condition of pre-emptive therapy of active CMV infection, in CMV positive renal transplant recipients. The influence of the two prevention concepts on the occurrence of direct and indirect effects of active CMV infections will be compared. The anticipated time on study treatment is 3 months-1 year, and the target sample size is 100-500 individuals.
Objectives of this trial are to: 1. Evaluate the kinetics and magnitude of the CMV-specific immune response post-Towne challenge (3000 pfu) in healthy CMV-seronegative volunteers who received VCL CT02 administered ID or IM 9 to 15 months previously as measured by: 1) ELISA and/or virus-neutralizing antibody titers for gB; 2) T-cell IFN-g ELISPOT; 3) T-cell proliferation assays (CFSE) for IE1, pp65, and/or gB; and possibly 4) cytokine and phenotypic flow cytometry responses to pp65, IE1, and/or gB. 2. Evaluate the safety safety of Towne challenge in healthy CMV-seronegative adult subjects who have previously been immunized with a trivalent pDNA CMV vaccine (VCL-CT02) administered intramuscularly (IM) or intradermally (ID). Our hypothesis is that the immune response to Towne vaccine 3000 pfu challenge after VLC-CT02 priming will be greater than that after Towne vaccination alone (concurrent controls will be administered Towne alone in a concurrent, companion trial).
This study will evaluate the safety and effectiveness of a new vaccine, ALVAC-pp65, in boosting immunity to cytomegalovirus (CMV) infection in stem cell transplant donors. CMV is a member of the herpesvirus group, which includes herpes simplex virus types 1 and 2, varicella-zoster virus (which causes chickenpox), and Epstein-Barr virus (which causes infectious mononucleosis). Most adults are infected with CMV, but a healthy immune system keeps the virus in check, so that it does not cause harm. In people with a weakened immune system, such as transplant recipients, the virus can become reactivated. Medications for treating the infection may cause low blood counts and kidney damage, and, in some cases, the virus may cause death. The ALVAC-pp65 vaccine is intended to improve immunity against CMV in stem cell donors and thereby prevent its reactivation in recipients. It is made from a virus that ordinarily infects canaries. The virus is weakened so that it cannot infect the person who receives it, and it is modified to carry a copy of a CMV gene called pp65. This gene instructs cells to make CMV proteins that the vaccine recipient's immune system can produce antibodies to, thus conferring immunity to the disease. Persons 18 years of age or older who are scheduled to donate stem cells for a patient in an NIH protocol and who are not allergic to eggs, egg products, or other vaccines, may be eligible for this study. Candidates are screened with a medical history, physical examination, and blood tests. Participants receive three vaccinations one week apart beginning at least 3 weeks before the scheduled stem cell donation. They are observed for 30 minutes after each vaccination to look for any immediate side effects of the vaccine. Approximately 3 tablespoons of blood are drawn before each vaccination and 1 week after the last vaccination to evaluate vaccine safety. Blood samples are also collected at the screening evaluation, 3 weeks after the start of vaccination, and 3 months after the last vaccination to check for CMV immunity. Participants keep a diary, recording any reactions to the vaccine and any change in medications. They are contacted by telephone for follow-up 3 months after the last vaccination to report any additional symptoms.
The purpose of this study is to find out more about cytomegalovirus (CMV) and how it is spread between people. One thousand adolescent males ages 12-17 years will participate in this study. Participants will be given a questionnaire about risk factors for CMV. A small blood sample (2-3 teaspoons) will be taken to test for CMV infection. Subjects that are CMV seronegative may participate in the second part of this study, which will involve returning to the clinic at regularly scheduled visit times to provide blood, urine, and saliva (spit) samples. This part of the study will take at least 24 months to complete. Subjects that test positive for CMV during the 2nd portion of the study will be invited to participate in the 3rd part of the study. This part of the study will require 8 regularly scheduled visits to provide blood, urine and saliva samples, over a 12-month period. The maximum amount of time a subject will participate in the study is 36 months.
Patients who receive transplants are at increased risk of developing serious cytomegalovirus (CMV) infections because they have a decreased immune system. The purpose of this study is to evaluate the safety and immune response of a CMV vaccine in patients (18 years old and older) who are awaiting a transplant. Following immunization with vaccine or placebo (inactive substance), patients will be followed for the development of immune responses to CMV and for evidence of CMV infection following transplantation. One hundred forty eligible patients will receive 3 injections of the CMV gB vaccine or 3 doses of placebo during 5 visits. Participants will participate in the study for approximately 7 months (if they do not undergo a transplant) or 10 months (if they undergo a transplant).
This study will determine the relative efficacy and safety of up to 100 days Valcyte prophylaxis relative to up to 200 days Valcyte prophylaxis when given for the prevention of CMV disease in high-risk (D+/R-) kidney allograft recipients. The anticipated time on study treatment is 3-12 months and the target sample size is 100-500 individuals.
Human cytomegalovirus (HCMV) has remained a major cause of morbidity and mortality following allogeneic bone marrow or peripheral blood stem cell transplantation (SCT). The most reliable virological predictive marker for disease development is the presence of HCMV viremia. It has been further recognized that viral load, and viral load kinetics are important determinants of pathogenesis. Prior to the preventive use of antiviral agents, CMV disease occurred in 15-45% of at-risk patients and carried a high mortality rate. In the last decade, major advances in the prevention of CMV disease have occurred with the application of pp65 antigenemia and qualitative/quantitative polymerase chain reaction (PCR) assays for the rapid and sensitive diagnosis of HCMV infection, combined with preemptive antiviral treatment targeted to patients with viremia. The prevalence of early CMV disease has declined to 3% to 6% with intense antiviral drug use. All antiviral drugs currently used for the treatment of systemic HCMV infection, including ganciclovir, foscarnet, and cidofovir, target the HCMV DNA polymerase. Ganciclovir is the most widely used drug for preemptive treatment. However, ganciclovir treatment is often complicated by bone marrow toxicity with the occasional development of potentially life-threatening thrombocytopenia, granulocytopenia, and graft failure, associated with secondary bacterial and fungal infection. Another limitation of preemptive ganciclovir therapy is the requirement for intravenous administration. The currently available oral valganciclovir is not yet approved for preemptive therapy in SCT recipients, and is associated with high treatment cost. Additionally, prolonged or repeated ganciclovir treatment may lead to the development of drug resistance. The use of foscarnet and cidofovir is limited by considerable nephrotoxicity, low oral bioavailability, and high cost. Thus, there is an increasing need for new effective non-toxic, low-cost anti-HCMV drugs with high oral bioavailability. Recently, the anti-malaria drug artesunate, which is widely used in the treatment of severe malaria, has been shown to be a highly effective inhibitor of HCMV in vitro. Artesunate exhibited similar antiviral activity (same micromolar range) to that of ganciclovir, while demonstrating no cytotoxicity. Importantly, its antiviral activity has been further demonstrated in vivo in a rat CMV model. No significant side effects were demonstrated in a number of pre-clinical and clinical studies, and artemisinin and its derivatives have been shown to be well-tolerated and safe in adults and children. Several million people have taken artemisinins to date, with no significant adverse or treatment-limiting effects being reported. Although neurotoxicity has been reported with supraphysiological doses in animals, it has not been documented in humans. Meta-analyses of malaria patients treated with artemisinins demonstrated that this drug class is safe. In rare cases, however, slight changes to haematology values have been seen, including a reduction in the number of reticulocytes as well as a slight increase in transaminase levels. These signs, however, do not generally give rise to any noticeable clinical manifestations. In rare cases, a slight but transient reduction in sinus heart rate has been observed. Abdominal cramps and mild diarrhoea have been reported at elevated doses. Thus, one might expect a similarly high degree of safety for the potential use of artesunate as an antiviral drug for HCMV infection. Thus, oral therapy with artesunate could be a beneficial option to the current therapies for the preemptive treatment of HCMV disease in SCT recipients.
This study is being done in stem cell transplant recipients to see if taking the drug valganciclovir can prevent or reduce serious cytomegalovirus (CMV) infections that can occur 100 days or later after transplant.