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NCT06148025
The goal of this clinical trial is to examine immune responses to the BCG vaccine in healthy adults who have, or who have not, taken antibiotics to deplete their gut bacteria prior to vaccination. The main question it aims to answer is: does depletion of the gut microbiota lead to impaired BCG-induced protection against specific and non-specific to challenges to the immune system?
NCT06821100
The goal of this research is to learn more about ZADAXIN® (trade name; thymalfasin generic; Ta1 for short) and determine if Ta1 has any benefit in increasing the immune response to the COVID-19 vaccine. Ta1 has been shown to stimulate the immune system to fight infections. This research study will test the safety and possible harms of Ta1 when it is given to people at different dose levels before COVID-19 vaccination.
NCT05060991
Immunocompromised individuals, such as solid organ transplant (SOT) recipients are at high risk of COVID-19 associated complications and mortality. Retrospective studies so far have shown that a majority of SOT recipients did not develop appreciable anti-spike antibody response after a first, second, or even third dose of mRNA vaccine. Treatment with antimetabolites was associated with poor vaccine response. The goal of this study is 1) examine whether transient immunosuppression reduction improves the immune response to a third dose of SARS-CoV-2 mRNA vaccine in kidney transplant recipients and 2) to assess the safety of immunosuppression reduction before and after third dose SARS-CoV-2 mRNA vaccination.
NCT06827873
The aim of this clinical trial is to explore the efficacy of fatty acid and bile acid based supplements on enhancing influenza vaccine immune response in adults aged 60-70 years. The objectives of this study are: 1. To explore the efficacy of fatty acid and bile acid based supplements on enhancing flu vaccine immune response. 2. To evaluate the safety of fatty acid and bile acid use in elders. 3. To explore the potential role of microbiota in regulating immune response. This study will conduct a randomized clinical trial to compare the efficacy of fatty acid / bile acid (Tauro Ursodesoxy Cholic Acid, TUDCA)supplements on enhancing vaccine immune response. The antibody's titer and safety indicators after influenza vaccination will be evaluated. Study process are: 1. Participants will be required to intake the assigned supplement or placebo daily for 25 days; 2. Receive a influenza vaccine on day 4; 3. Provide blood samples three times and stool samples twice at base line and endpoint respectively; 4. The antibody's titer and safety indicators will be analyzed and compared among groups. This study aims to establish a theoretical foundation for utilizing nutritional strategies to enhance vaccine-induced immune responses and to provide a scientific framework for developing oral vaccine boosters.
NCT06635525
The aim of this observational study is to determine if and how kidney failure affects the development of protective immune responses following vaccination in patients on chronic dialysis. Researchers will compare the effectiveness of the influenza vaccine in inducing protective antibodies between hemodialysis patients and subjects without chronic kidney disease. Participants will: * Be enrolled at the time of influenza vaccination * Visit the clinic at 7, 14, 30, 60, and 120 days after vaccination * Be asked to provide relevant clinical information and a blood sample at each visit
NCT05116748
Background: ISHLT and AASLD guidelines recommend SARS-CoV2 vaccination in all individuals undergoing lung and liver transplantation, but there are currently scarce data on the safety and efficacy of these vaccines in this population. In Italy, immunocompromised patients have received the indication to be administered mRNA vaccines only. Primary outcome: safety and reactogenicity Secondary outcomes: immunogenicity and prevention of COVID19 Visits and timepoints: * T0: before first dose administration: visit and venous sampling to assess baseline COVID19 serum status * Telephone calls to assess safety and reactogenicity 1 and 2 days after each dose of vaccination * T21 or 28 (based on vaccine; mRNA BNT162b2 and mRNA-1273, respectively): visit, venous sampling to assess immunogenicity * Follow up visits after 60, 120, 180 and 365 from T0: visit and venous sampling to assess immunogenicity
NCT05791851
The goal of this natural history study is to examine the immune responses to the Heplisav-B vaccine in Veterans living with HIV who were non-responders to prior HBV vaccination. A comparison group of HBV vaccine nonresponders without HIV infection will be enrolled to characterize the HIV-associated immune alterations that affect vaccine response. The investigators hypothesize that TLR9-mediated innate immune stimulation with Heplisav will elicit HBV seroprotection despite prior vaccination failures in persons living with HIV, compared to HIV uninfected individuals. Participants eligible for Heplisav-B vaccination will be asked to provide blood samples at multiple timepoints before and after their vaccination.
NCT03855176
Though HAV is mainly transmitted through the fecal-oral route, infection by sexual intercourse and blood transfusion is also possible. Injection drug users (IDUs) and men who have sex with men (MSM) have a higher risk of acquiring HAV due to their behaviors. Reemerging threat of hepatitis A among MSM in Taiwan has been reported recently. Based on the guidelines for the diagnosis and treatment of HIV/AIDS and the Advisory Committee on Immunization Practices (ACIP), Taiwan, vaccination of individuals against HAV with any of the following indications is recommended: HIV patients, adults with chronic hepatic disease, hemophilia, liver transplantation, occupational exposure, MSM, persons who use injection or noninjection illicit drugs, or persons traveling to or working in countries that have endemicity of HAV. In HIV-infected patients, the immunogenicity to HAV vaccination is sub-optimal in HIV-infected patients and the seroconversion rate is estimated 68-90% after administration of 2 or 3 doses of HAV vaccine. Furthermore, the antibody titers of HIV-infected patients following HAV vaccination are significantly lower compared to those of HIV-uninfected persons. The sub-optimal response among HIV-infected subjects remains an unresolved problem. In this study, the investigators aim to determine the to conduct a randomized clinical trial to compare the immunogenicity of 2 different doses of HAV vaccination (1 dose versus 2 doses) in HIV-infected patients who failed to achieve serologic response in the primary vaccination. This proposal will provide the solid evidence to elucidate the role of booster HAV vaccination in HIV-infected patients without response to primary HAV vaccination.
NCT03930017
As the global availability of vaccines increases, and reaches areas disproportionately affected by arsenic and malnutrition, resolving questions about potential environmental and biologic barriers to maternal immunization has become increasingly urgent. It is not known whether arsenic, a known developmental toxicant, can alter maternal immune responses to vaccination and whether exposure to arsenic during pregnancy can impair the transfer of maternal vaccine-induced antibody to the newborn. Moreover, factors known to affect arsenic metabolism and toxicity outcomes, particularly micronutrients critical in one-carbon metabolism, have not been evaluated in studies of arsenic immunotoxicity and vaccine-induced protection in mothers and their newborns. The objective in this study is to investigate whether maternal arsenic exposure and one-carbon metabolism micronutrient deficiencies alter maternal and newborn measures of vaccine-induced protection, respiratory morbidity, and systemic immune function following influenza vaccination during pregnancy.
NCT04743947
This is a prospective, multi-center, observational study that will enroll patients receiving dialysis (hemodialysis or peritoneal dialysis) or patients with kidney transplantation who will be vaccinated against COVID-19.
NCT04059991
Viruses with high mutation rates, such influenza or HIV, pose a major challenge for vaccine design. The current influenza vaccination strategy of yearly vaccination with adapted strains aims to maximally diversify the antibody immune response to prevent viral escape. There is, however, growing evidence, that repeated vaccination with very similar viral proteins might limit, instead of broaden, diversification and thereby reduce vaccine efficacy. The ARIVA Study prospectively studies the immunological impact of repeated influenza vaccination on viral variant recognition and antibody responses in healthy subjects cross-sectionally and over three consecutive vaccination seasons.
NCT05019248
The primary objective of this study is to characterize the antibody response to seasonal influenza vaccine, in patients with active RRMS, treated with cladribine, compared to control individuals with basic immunomodulatory treatment. Serum antibody titers against the respective pathogen will be assessed prior to and 6 to 8 months following vaccination.
NCT04910971
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic presents a great challenge to global health. The first case was identified in December 2019 in Wuhan, China and since has infected nearly 100 million people and claimed almost 2 million lives worldwide. In response, the medical community and scientists have worked hard to develop effective therapies and guidelines to treat a wide range of symptoms including the use of the antiviral drug remdesivir, convalescent plasma, antibiotics, steroids, and anticoagulant therapy. To prevent the spread of the disease, multiple vaccines based on mRNA and DNA technologies that include inactivated viral components have been developed and millions of doses are currently being administered worldwide. Early analysis of data from the phase III Pfizer/BioNTech and Moderna vaccine trials suggested the vaccine was more than 90% effective in preventing the illness with a good safety profile (Polack et al., 2020). However, there are still many unknowns regarding the long-term safety of these newer vaccine technologies and the level and duration of immunogenicity. SARS-CoV-2 infection results in seroconversion and production of anti-SARS-CoV-2 antibodies. The antibodies may suppress viral replication through neutralization but might also participate in COVID-19 pathogenesis through a process termed antibody-dependent enhancement (Lu et al., 2020). Rapid progress has been made in the research of antibody response and therapy in COVID-19 patients, including characterization of the clinical features of antibody responses in different populations infected by SARS-CoV-2, treatment of COVID-19 patients with convalescent plasma and intravenous immunoglobin products, isolation and characterization of a large panel of monoclonal neutralizing antibodies and early clinical testing, as well as clinical results from several COVID-19 vaccine candidates. In this study, we plan to assess the effic of both vaccines on the healthcare workers. As healthcare workers begin to receive their first vaccination dosage, we will start looking for traces of antibodies within the blood and saliva. The data provided will help us determine the efficacy of the vaccine over a period of 1 year, identify any difference in efficacy amongst different populations (gender, age, and ethnicities) differences among vaccine types, demographics and follow-up on any potential side effects. We will collaborate with Nirmidas Biotech Inc. based in Palto Alto, California, a Stanford University spinoff on this project. Nirmidas Biotech. Inc is a young diagnostic company that have received several FDA EUA tests for COVID-19. We will perform IgG/IgM antibody detection by the NIRMIDAS MidaSpot™ COVID-19 Antibody Combo Detection Kit approved by FDA EUA for POC testing in our hospital site for qualitative antibody testing. We will then send dry blood spot and saliva to Nirmidas for the pGOLD™ COVID-19 High Accuracy IgG/IgM Assay to quantify antibody levels and avidity, both of which are important to immunity. The pGOLD assay is a novel nanotechnology assay platform capable of quantifying antibody levels and binding affinity to viruses. We collaborated recently with Nirmidas on this platform and published a joint paper in Nature Biomedical Engineering on COVID-19 Ab pGOLD assay (Liu et al., 2020). It is also capable of detecting antibodies in saliva samples and could offer a non-invasive approach to assessing antibody response for vaccination.
NCT01989533
Background: \- Vaccines create resistance to disease. This study tests experimental human immunodeficiency virus (HIV) vaccines that use an adenovirus as a transporter. Transporters may help vaccines stimulate an immune response against HIV. This means the body works to fight infection. Researchers want to see if different ways of giving the vaccines cause different immune responses. They also want to see if the vaccines adenovirus is contagious. Adenoviruses cause cold symptoms or mild eye infections. Participants cannot get HIV from these vaccines. But they can get the adenovirus, so their entire household and intimate contacts must participate. Objective: \- To test the safety of experimental HIV vaccines. Eligibility: \- Healthy adults 18-49 years old. Design: * Participants will be screened with medical history, physical exam, and blood and urine tests. * Participants will receive the vaccine 3 times over 6 months. Each time, they will have a physical exam and blood and urine tests. Samples will be taken from their nose, rectum, and cervix. * Some participants will receive the vaccine by swallowing 11 capsules with water. Clinic staff will observe them for 1 hour. * Some participants will receive the vaccine swabbed in their throat. They will get dose 1 at the hospital and stay there for 1 week. They will have medical tests and nose swabs. Doses 2 and 3 will not require a hospital stay. * Participants will have 7 follow-up visits over 6 months, with a physical exam and blood tests. Samples will be taken from their nose, throat, and rectum. * Household and intimate contacts will have 4 clinic visits over 8 months, with a physical exam and blood tests.