Clinical Research Directory

BPL-1357 Against H1N1 Influenza Virus Challenge

Background: Influenza (flu) infections are a serious global health threat. Each year, between 3 and 5 million people get the flu, and up to 500,000 die from it. Current vaccines protect against seasonal flus, but broader vaccines are needed to protect against potential flu pandemics. Objective: To test an experimental flu vaccine. Eligibility: Healthy people aged 18 to 55 years. Design: The study will last 5 to 8 months and has 2 phases, A and B. The study vaccine will be given either as a shot in the arm or as a nasal spray. Participants will receive 1 of 3 combinations: (1) study vaccine in the nose and placebo in the arm; (2) placebo in the nose and study vaccine in the arm; or (3) placebo in the nose and placebo in the arm. A placebo is just like the real vaccine but contains no active ingredients. Phase A: Participants will have 5 clinic visits over 56 days. They will receive a shot and a nasal spray at 2 of the visits, 28 days apart. At each visit, they will have a physical exam, with tests of their blood, urine, and nasal secretions. They will check their temperature at home and record any symptoms for 7 days after each vaccine. Phase B: Participants will stay in the hospital for at least 9 days. They will be infected with a flu virus. They will provide blood, urine, and nasal fluid samples. They will have tests of their heart function. They will remain in the hospital until they test negative for the flu 2 days in a row. They will have 2 follow-up visits, 4 and 8 weeks after leaving the hospital. ...

Flu COVID Vaccine Views

This study addresses a critical evidence gap relevant to implementation strategies for combination vaccines in health care settings. This study will specifically investigate healthcare worker (HCWs) attitudes around and willingness to receive combination influenza/COVID-19 vaccines. Findings will identify determinants of hesitancy and acceptance among HCWs and support effective rollout strategies and communication approaches. Cross-sectional surveys and qualitative interviews will be conducted with healthcare workers to characterize HCW willingness to be vaccinated and to identify demographic, attitudinal, and structural predictors of vaccination.

Safety and Immunogenicity of Chimeric Hemagglutinin mRNA Vaccine Candidates

This is a Phase 1, randomized, controlled, dose-ranging clinical trial to assess the safety and immunogenicity of novel influenza A Group 1 and influenza A Group 2 mRNA chimeric hemagglutinin (HA) vaccine candidates given as intramuscular injections alone and in combination. A total of 60 healthy men and non-pregnant, non-breastfeeding women aged 18 through 59 years will be enrolled in one of 6 study arms. The 6 arms will consist of: 1) Sequential influenza A Group 1 mRNA chimeric hemagglutinin: cH8/1 (25 µg) followed by cH5/1 (25 µg), 2) Sequential influenza A Group 2 mRNA chimeric hemagglutinin: cH15/3 (25 µg) followed by cH4/3 (25 µg), 3) Sequential combined influenza A Group 1 and Group 2 mRNA chimeric hemagglutinin: cH8/1 + cH15/3 (25 µg) followed by cH5/1 + cH4/3 (25 µg), 4) A single dose of combined influenza A Group 1 and Group 2 mRNA chimeric hemagglutinin: cH8/1 + cH15/3 (50 µg) followed by placebo, 5) A single dose of combined influenza A Group 1 and Group 2 mRNA chimeric hemagglutinin: cH5/1 + cH4/3 (50 µg) followed by placebo, 6) Sequential combined influenza A Group 1 and Group 2 mRNA chimeric hemagglutinin: cH8/1 + cH15/3 (50 µg) followed by cH5/1 + cH4/3 (50 µg). The primary objectives are to evaluate safety and immunogenicity: 1) To assess the safety and reactogenicity of one or two doses of monovalent or bivalent Group 1 and 2 study products and 2) To describe the Group 1 and 2 anti-HA stalk IgG antibody responses of one or two doses of monovalent or bivalent Group 1 and 2 study products by ELISA.

Longitudinal Deep Phenotyping of Central Mechanisms in Dysosmia: A Pilot Study Using Electrobulbogram (EBG), Functional MRI (fMRI), and Diffusion-Weighted Imaging (DWI)

Background: Loss of the sense of smell can seriously affect a person's quality of life. The ability to smell can be damaged by many factors, including illnesses, injuries, and exposure to toxic chemicals. The effects can vary, including complete loss of smell, partial loss, and parosomia, which is when things smell differently than they should. Objective: To study how brain function changes in people with different types of smell disorders. Also, to look at how smell loss affects quality of life over time. Eligibility: People aged 18 years or older with a disorder that affects their sense of smell. Healthy volunteers are also needed. Design: Participants will have 5 study visits over 1 year. They will have various tests and procedures: Smell tests. They will have several tests that involve smelling different items and answering questions. Questionnaires. They will answer questions about their health, mood, sense of smell, and daily habits. Magnetic resonance imaging (MRI) scans. They will lie on a bed that slides into a tube. Padding will hold their head still. They will smell different odors while in the scanner. Electrobulbogram (EBG). They will wear a soft cap with sensors that measure brain activity. They will smell different odors while wearing the cap. Nasal endoscopy. A flexible tube will be inserted into a nostril to view the inside of the nose. Biopsy. A numbing substance will be sprayed into the nose. Then a scissor-like tool will be used to collect a sample of tissue from one or both nasal passages. Samples of blood, urine, and nasal fluid will be taken.

pH1N1 Blinded Challenge Study

This protocol describes a clinical trial to develop and validate a Controlled Human Infection Model (CHIM) for influenza A/Arkansas/08/2020 (pH1N1). The study is designed to determine the optimal infectious dose of the pH1N1 challenge strain for use in future clinical trials evaluating influenza countermeasures. The study will enroll and challenge adult volunteers with the pH1N1 influenza virus challenge or sham inoculations. Given the adaptive design of this trial, the potential number of participants can vary. Depending on the pathway recommended by the PSRT and followed in the Trial Schema, the study population can range from around 30 to 99. The anticipated final sample size will be approximately 90 receiving pH1N1 challenge product plus and 6 persons receiving a sham inoculation. Participants will be pre-screened for health and for serological HAI antibody titers of \</1:40 against the challenge strain. Eligible participants will be enrolled sequentially into challenge cohorts and will be randomly assigned to receive a single dose of either sham inoculation or the interventional study product at a dose between 10\^6 to 10\^7 TCID50 (or 10\^5 TCID50 if needed). Dose titration will be conducted under an adaptive escalation schedule whereby dosing will start at 10\^6 TCID50 and escalate to the next dose if a pre-determined symptomatic influenza attack rate and clinical symptom score thresholds are not met and if the dose is determined to be safe with no pre-defined halting criteria being met. The primary objectives of this study are to determine the optimal infectious dose of a pH1N1 viral challenge to cause laboratory-confirmed clinical influenza and to assess the safety profile of pH1N1 viral challenge.

Safety and Immunogenicity of GPO Seasonal Tetravalent Inactivated Split Virion Influenza Vaccine in Healthy Thais

The study is aim to evaluate the safety and immunogenicity of one dose TetraFluvac TF vaccine (15 μg HA per strain per dose) of the GPO seasonal quadrivalent inactivated split virion influenza vaccine in healthy adults aged 18 years and above over 90 days post-injection.

Light-based Immunomodulation for Guarding Against Human Respiratory Tract Infections

The purpose of trial is to determine if daily usage of a photobiomodulation device will decrease the incidence of upper respiratory tract infections (URI) due to COVID, influenza or other viruses.The RD-X10 device is handheld, can be self-administered, and has been shown to be safe in invivo studies.

A Clinical Study to Investigate the Safety and Immunogenicity in Relation to Product Attributes of mRNA-1083 (Severe Acute Respiratory Syndrome Coronavirus 2 [SARS-CoV-2] and Influenza Vaccine)

The purpose of this study is to evaluate the safety, reactogenicity, and immunogenicity in relation to the product attributes of mRNA-1083 vaccine when administered as a single intramuscular (IM) injection in adults ≥50 to \<65 years of age.

High vs. Standard Dose Influenza Vaccine in Adult SOT Recipients

The influenza virus is a significant cause of morbidity in adult solid organ transplant (SOT) recipients. However, these individuals show a suboptimal response to vaccines including the standard-dose (SD) inactivated influenza vaccine (IIV). Recent studies have investigated two strategies to overcome poor immune responses in SOT recipients: (1) administration of high-dose (HD)-IIV compared to SD-IIV and (2) two doses of SD-IIV compared to one dose of SD-IIV in the same influenza season. The first study compared HD-IIV vs. SD-IIV in adult SOT and noted HD-IIV was safe and reported higher immunogenicity; however, the median post-transplant period was 38 months. In another phase II trial of adult SOT recipients, two doses of SD-IIV a month apart compared to one-dose SD-IIV revealed increased immunogenicity, with a median post-transplantation period of 18 months. Therefore, these studies lack evaluation in the early post-transplantation period in this vulnerable population when influenza disease is most severe. The administration of two-doses of HD-IIV in the same influenza season has also not been studied in SOT recipients. Moreover, the vast majority of SOT influenza vaccinations studies have not substantively evaluated prolonged immunogenicity. Thus, the optimal immunization strategy for SOT recipients less than 12 months post-transplant is poorly-defined. In addition, the immunologic predictors and correlates of influenza vaccine immunogenicity in SOT recipients have not been defined. The investigators hypothesize that adult solid organ transplant recipients that are 1-11 months out from transplant and are receiving high-dose inactivated influenza vaccine will have higher hemagglutination inhibition (HAI) geometric mean titers to influenza A antigens compared to adult SOT recipients receiving standard-dose inactivated influenza vaccine. To test this hypothesis and address the above critical knowledge gaps, The investigators propose to conduct a phase II multicenter randomized controlled trial comparing either two doses HD-IIV, two doses of SD-IIV, or one-dose of HD-IIV in adult kidney, heart, and liver SOT recipients 1-11 months post-transplantation. The results of this study will address significant gaps in knowledge regarding influenza vaccine strategies and immune responses in adult SOT recipients and will guide vaccine recommendations in this vulnerable population.

Clinical Outcomes and Pharmacotherapy Effectiveness in the VA Health Care System (COPE-VA)

The purpose of this study is to comprehensively describe the temporal and geographic utilization of COVID-19 therapies used for mild to moderate disease during different periods of SARS-CoV-2 variant circulation as well as to compare demographic and clinical characteristics of Veterans who are treated or do not receive these different therapies. The investigators will also perform similar descriptive epidemiology for other respiratory viruses, including RSV and influenza and other infectious diseases. This first phase will critically inform feasibility and direction of the second phase, in which the investigators will use target trial emulation design to study the comparative effectiveness of therapies and vaccines for COVID-19, respiratory viruses, including RSV, and influenza, and other infectious diseases.

Equity Evaluation of Fact Boxes on Informed COVID-19 and Influenza Vaccination Decisions - Study Protocol

The study aims to evaluate whether evidence-based fact boxes on COVID-19 and influenza vaccination contribute to the decision making of laypeople from different social backgrounds in different educational settings (e.g. medical practices, outreach work). Furthermore, the study will investigate whether evidence-based fact boxes can contribute to more equitable health care by improving shared decision-making.

Communication Intervention to Improve Influenza Vaccination Rates Among Elderly in Can Tho

This study evaluates the effectiveness of a multi-component community-based communication intervention to increase influenza vaccination rates among adults aged above 65 years in Can Tho City, Vietnam. Using a cluster randomised controlled trial design with stratified lottery randomisation, four study sites were selected from eight sites surveyed in a prior study: O Mon Ward and Truong Thanh Commune (intervention); Phuoc Thoi Ward and Truong Xuan Commune (control). The intervention includes community health education sessions, healthcare worker training, household visits, health communication banners, and Zalo-based vaccination reminders, delivered over 12 months (September 2025 to September 2026). Effectiveness is assessed by comparing pre- and post-intervention outcomes using Difference-in-Differences (DID) analysis.

High vs.Standard Dose Influenza Vaccine in Pediatric Solid Organ Transplant (SOT) Recipients

Influenza virus is a significant pathogen in pediatric solid organ transplant (SOT) recipients. However, these individuals respond poorly to standard-dose (SD) inactivated influenza vaccine (IIV). Recent studies have investigated two strategies to overcome poor immune responses in SOT recipients: (1) administration of high-dose (HD)-IIV compared to SD-IIV and (2) two doses of SD-IIV compared to one dose of SD-IIV in the same influenza season. One study compared HD-IIV vs. SD-IIV in adult SOT recipients and noted that HD-IIV was safe and more immunogenic; however, the median post-transplant period was 38 months. A phase I pediatric study comparing a single dose of HD-IIV vs. SD-IIV was safe with higher immunogenicity, but the study was limited by small sample size and median post-transplant vaccine administration was 26 months. In another phase II trial of adult SOT recipients, two doses of SD-IIV one month apart compared to one-dose of SD-IIV revealed modestly increased immunogenicity when given at a median of 18 months post-transplant. Therefore, these studies lack both evaluation in the early post-transplant period and substantive pediatric populations. Additionally, the administration of two-doses of HD-IIV in the same influenza season has not been evaluated in pediatric SOT recipients. Thus, the optimal immunization strategy for pediatric SOT recipients less than 24 months post-transplant is unknown. In addition, immunologic predictors and correlates of influenza vaccine immunogenicity in pediatric SOT recipients have not been well-defined. The central hypothesis of our proposal is that pediatric SOT recipients 1-23 months post-transplant who receive two doses of HD-quadrivalent inactivated influenza vaccine (QIV) will have similar safety but higher Hemagglutination Inhibition (HAI) geometric mean titers (GMTs) to influenza antigens compared to pediatric SOT recipients receiving two doses of SD-QIV.

A Surveillance Study of Susceptibility to Baloxavir Marboxil in Pediatric Participants With Influenza and Transmission of Influenza to Household Contacts

This study consists of two parts: Part A Surveillance and Part B Transmission. The main purpose of Part A is to evaluate the prevalence of pre-dose and treatment-emergent amino acid substitutions in pediatric participants' \<12 years with influenza treated with baloxavir marboxil. Part B will include a subset of Part A participants who have household contacts (HHCs) recruited to the study. Part B will evaluate the incidence of onward influenza transmission from pediatric index participants (IPs) under 5 years of age and those aged 5 to under 12 years, treated with baloxavir marboxil, to their HHCs. Participants will no longer be enrolled to Part B Transmission as per protocol version 3.

Immune Responses to Dengue and Sepsis

The goal of this research study is to help the investigators better understand serious dengue disease. The investigators will collect clinical information and up to four blood samples from participants with dengue, influenza, sepsis, or healthy people. The investigators will perform multiple analyses on the blood samples and compare results between dengue patients and those with influenza or sepsis and healthy people.

Phase I Clinical Trial of Influenza Vaccine (Split Virion), Inactivated (High Dose)

This is a randomized, double-blind, active-controlled Phase I clinical trial to evaluate the safety and immunogenicity of Influenza Vaccine (Split Virion), Inactivated (High Dose) developed by Sinovac.

Screening for LID Clinical Studies Unit Healthy Volunteer Protocols

Background: * The Laboratory of Infectious Diseases (LID) Clinical Studies Unit (CSU) enrolls healthy volunteers into clinical studies to study infectious diseases. * Viruses can be highly infectious and contagious. They cause considerable illness in the United States each year and a good example of this is influenza (the flu). The LID CSU performs clinical studies to learn about these viral infections and assist in the development of vaccines and treatments for the infections. These clinical studies include influenza "challenge studies" as well as natural history studies and phase I trials involving vaccines for viruses carried by mosquitos such as Zika or Dengue virus. * In influenza challenge studies studies, doctors expose a person to a flu virus. Then they study the flu through the body's natural healing process. This information will help to find better ways to prevent the flu and may also improve treatments for the flu. * Natural history studies and phase I trials of new vaccines are performed so the researchers can learn how some viral infections occur and if new vaccines are safe and potentially effective in preventing the infections. In some of these studies, participants experience insect bites with special clean (non-infected) insects (such as mosquitos) to better understand the role of insects in these infections. Objectives: \- To screen healthy volunteers for future CSU studies. Eligibility: \- Healthy people between the ages of 18 and 65 Design: * The 3- to 5-hour screening exam includes the following: * Medical history and physical exam * Standard blood tests including pregnancy, Hepatitis B and C, and HIV tests * Standard urine drug testing * Electrocardiogram (ECG) to test heart rhythm and function * Chest x-ray * Eligible volunteers are enrolled in the study for up to 1 year, until they take part in a CSU study or are found to be ineligible to participate. * Volunteers may withdraw from the study pool at any time.

H1ssF Flu Vaccine Clinical Trial

This is a two-arm, open-label, randomized, phase 1, controlled clinical trial intended to evaluate the safety and immunologic response to the experimental vaccine H1ssF (H1 stabilized stem ferritin nanoparticle) and the seasonal flu vaccine Flucelvax.

Cellular and Molecular Characterization of the Immune Response in Healthy NIH Employees atBaseline, and After Immunization With the H1N1 or Seasonal Influenza Vaccines

Background: \- Seasonal influenza is a major health problem whose impact is typically reduced by vaccination. The H1N1 (swine flu) influenza virus is an emerging pathogen that has the potential to cause devastating illness and even death in the coming months. Currently, there are limited data on the cellular and molecular immune responses in adult recipients of either the seasonal or the H1N1 influenza vaccines. Objectives: \- To obtain blood and nasal wash samples and perform laboratory studies to characterize the immune response in healthy adult volunteers at baseline and after immunization with the seasonal or H1N1 influenza vaccines. Eligibility: \- Adult employees at least 18 years of age of the NIH Clinical Center who are deemed healthy by a brief medical history and physical examination and routine blood testing. Design: * Before the start of the influenza season, volunteers will receive either the seasonal influenza vaccine or the H1N1 vaccine when it becomes available. If the H1N1 vaccine is available at the start of the season, volunteers will receive both the seasonal vaccine and the H1N1 vaccine. * Blood will be drawn over an 8-week period. Volunteers must not eat anything for 8 hours prior to the blood draw. The sequence of the blood draws is as follows: 2 weeks before vaccination; right before vaccination; and 1, 7, 14, 28, and 60 days after vaccination. * Two to four nasal washings will be collected by a nurse before volunteers receive the vaccination(s) and 28 days after the vaccination. * Prevaccine and postvaccine blood and nasal wash samples will be compared to determine volunteers immune responses. * Research samples will be stored indefinitely and will be used strictly for laboratory experiments.

A Study to Evaluate the Safety and Efficacy of MK-1406/CD388 for Prevention of Influenza (MK-1406-005/CD388.SQ.3.06)

Approximately one billion cases of seasonal influenza occur annually. Of these, 3 to 5 million illnesses are severe and responsible for up to 650,000 deaths per year (WHO 2025). Yearly administration of an influenza vaccine for the prevention of influenza is currently recommended. However, the real-world vaccine effectiveness varied from 10% to 60% in the general population across the years of 2004 to 2024, with effectiveness in most years below 50% (CDC 2025) and decreasing to as low as 5% in immunocompromised individuals (Hughes 2021). The goal of this study is to learn whether MK-1406 (CD388) can help prevent the flu in people who are at higher risk of becoming seriously ill from influenza. Researchers want to find out if MK-1406 dosed at a single study visit can provide protection against influenza compared with placebo. The study will include adolescents and adults who may be more vulnerable to complications from influenza because of their age, health conditions, or weakened immune systems. Researchers will also evaluate the safety of MK-1406 and how well participants tolerate the study medicine.

Comparative Immunogenicity of Respiratory Virus Vaccines (CIRV2) Study

CIRV2 is a Phase IV randomized, open-label, trial of FDA-approved COVID-19 and/or influenza vaccines (no more than minimal risk) with longitudinal follow-up. In 2026 CIRV2 will compare immunogenicity and reactogenicity of the recombinant Novavax COVID-19 vaccine and the mRNA Pfizer-BioNTech COVID-19 vaccine.

Observational Digital Biomarker Discovery in Respiratory Virus Challenge Studies

Background: Respiratory viruses circulate throughout the year and around the globe. Wearable and sensor devices, like smartwatches, may be able to help monitor infectious diseases. Researchers want to use them to learn how respiratory viruses affect people in different ways. Objective: To use digital devices to collect data from participants in challenge studies that could indicate subtle changes in health during an infection that might otherwise go unnoticed. Eligibility: Healthy adults who have enrolled, were recently enrolled, or are scheduled to enroll in a challenge study. Design: Participants will stay at NIH for the duration of the challenge study (at least 9 days) and then will have outpatient follow-up visits (2-4). While at NIH, participants will wear a smartwatch at all times. It will record data like temperature, heart rate, breathing rate, and movements. Participants will have a smartphone that records at all times to listen for coughing and changes in voice. Participants will perform tasks every 4 hours during the daytime. They will record themselves coughing, breathing in deeply, and reading aloud. They will take videos of their face. They will play a game to test their reflexes and focus. They will measure their head temperature with their smartwatch. For outpatient visits, participants will use one smartphone and the smartwatch to complete the above tasks. Participants will be sent a smartwatch to wear at home at night to collect additional healthy data. Participation will last the duration of each challenge study, and may range from 10 weeks to 2 years.

Comparative Immunologic Mechanisms and Microbiome Interactions Following Different Influenza Vaccine Formulations in Older Adults

This prospective, randomized, open-label clinical study aims to evaluate the immunogenicity and underlying immune mechanisms of different influenza vaccine formulations in adults aged ≥65 years. Additionally, the study investigates the role of the gut microbiome in modulating vaccine-induced immune responses and durability.

High vs. Standard Dose Influenza Vaccine in Lung Allograft Recipients

Lung allograft recipients have a higher burden of influenza disease and greater associated morbidity and mortality compared with healthy controls. Induction and early maintenance immunosuppression is thought to impair immunogenicity to standard dose inactivated influenza vaccine. This early post-transplant period is when immunity is most desirable, since influenza disease during this time frame is associated with adverse consequences. Thus, strategies to reduce severe influenza disease in this highly susceptible population are critical. No trials in lung transplant recipients have evaluated two doses of HD-IIV within the same influenza season as a strategy to improve immunogenicity and durability of influenza prevention. Furthermore, no influenza vaccine trials have focused on enrollment of subjects at early post-transplant timepoints. Very few studies have been performed in solely lung allograft recipients. Immunosuppression intensity is highest in lung patients, thereby limiting comparisons to recipients of heart, liver, and kidney transplants. Therefore, studies to assess both HD-IIV and two-dose strategies in the same influenza season in post-lung transplant recipients are greatly needed. The central hypothesis of our proposal is that lung allograft recipients who are 1-35 months post-transplant and receiving two doses of HD-quadrivalent inactivated influenza vaccine (QIV) will have higher HAI geometric mean titers (GMT) to influenza antigens compared to those receiving two doses of SD-QIV. To test this hypothesis and address the above critical knowledge gaps, we propose to conduct a phase II, multi-center, randomized, double-blind, controlled immunogenicity and safety trial comparing the administration of two doses of HD-QIV to two doses of SD-QIV in lung allograft recipients 1-35 months post-transplant. The results of this clinical trial will address significant knowledge gaps regarding influenza vaccine strategies (e.g., one vs. two doses and HD-QIV vs. SD-QIV) and immune responses in lung transplant recipients and will guide vaccine recommendations during the post-transplant period.