Clinical Research Directory
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131 clinical studies listed.
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Tundra lists 131 Healthy Volunteer clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.
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NCT00001620
Screening for Hematology Branch Protocols
This study allows the evaluation of subjects in order to determine their ability to safely participate in other active research studies. After subjects complete the screening process, they will be offered the opportunity to participate in an active research study, or if no appropriate studies are available information and recommendations will be provided for other treatment options....
Gender: All
Ages: 2 Years - 100 Years
Updated: 2026-05-29
1 state
NCT07313787
Effects of Meal Macronutrients on Postprandial Lipids
Background: Abnormal fats in the blood can lead to many problems, including heart disease. Researchers want to learn more about how eating meals with different levels of nutrients affects fats in the blood. Specifically, they want to study people with too much body fat, too little body fat, and a kidney problem called nephrotic syndrome. Objective: To learn more about how different types of foods affect fat levels in the blood. Eligibility: People aged 18 years or older with a health condition that affects how their body handles fats. Healthy volunteers are also needed. Design: Participants will have 2 overnight stays in the clinic within 6 months. At each visit, after staying overnight, they will eat a breakfast casserole. At 1 visit, breakfast will be a high-fat, low carbohydrate meal. At the other, it will be a high-carbohydrate, low-fat meal. Participants will have a tube inserted into a vein in their arm. They will have blood drawn via the tube 12 times in 8 hours: 2 times before they eat the breakfast and 10 times after. Participants will have other tests during their stays: * A resting metabolic test captures the air they exhale and measures how much energy they use at rest. * A dual energy X-ray absorptiometry (DXA) scan measures how much fat and muscle they have. * A Fibroscan is a special type of ultrasound of the liver. * A body surface scan uses lasers to measure the total area of the body. * A bioelectric impedance (BIS) exam measures how fast small electric currents move through their body. Participants may opt to have a third visit. At this visit, the breakfast will be high in protein....
Gender: All
Ages: 18 Years - 120 Years
Updated: 2026-05-29
1 state
NCT02327884
Characterization of Diseases With Salivary Gland Involvement
Background: \- Salivary glands in and around the mouth and throat make saliva. Salivary gland disorders can affect a person s quality of life. Studying people who have a disease that affects their salivary gland(s) may teach researchers about the disorders and their genetics. Objectives: \- To study salivary gland diseases and disorders. To collect data and samples from people with salivary gland problems and their relatives. Eligibility: * People more than 4 years old who have or are suspected to have a disease involving salivary glands. * Their relatives more than 4 years old. * Healthy volunteers 18 years or older. Design: * Participants may be screened with: * Medical history * Physical exam * Blood and urine tests * General oral and dental history and exam * Saliva collection * Eye exam and test for dry eyes * Health questionnaires (adults) * Biopsy of some minor salivary glands. A small incision will be made on the inside of the lower lip and several tiny salivary glands will be removed. * Participants will have 2-3 visits. These may include: * Repeats of some screening tests * Ultrasounds of some glands. Researchers will put some gel on the face, then press on it with a smooth wand. * Adults may have other biopsies * A small catheter inserted into the opening of the parotid gland duct on the inside of the cheek. A saline solution (in a syringe) will fill the duct. * Swishing a saltwater solution in the mouth for 10 seconds and then spitting into a cup * Scrapings collected from teeth, tongue, and cheeks
Gender: All
Ages: 4 Years - 100 Years
Updated: 2026-05-29
1 state
NCT00004577
Study of New Magnetic Resonance Imaging Methods of the Brain
The purpose of this investigation is to develop improved magnetic resonance imaging (MRI) techniques and hardware for studying brain function. MRI is a diagnostic tool that provides information about brain chemistry and physiology. This study will evaluate new MRI methods for monitoring blood flow to regions of the brain in response to simple tasks. The MRI machine used in this study is more powerful than those in most hospitals, permitting a higher visual resolution. Normal healthy volunteers over 18 years old may be eligible for this study. Candidates will be screened with a medical history and questionnaire, and a neurological examination. Study participants will have a yearly MRI scan. For this procedure, the subject lies on a stretcher that is moved into a donut-shaped machine with a strong magnetic field. A lightweight circular or rectangular coil-a device that improves the quality of the images-may be placed on the head. The scan time varies from 20 minutes to 3 hours; most scans last between 45 and 90 minutes. During the scan, the subject may perform simple tasks, such as listening to tapes, tapping a finger, moving a hand, watching a screen, or smelling a fragrance. More complex tasks may require thinking about tones or pictures and responding to them by pressing buttons. Information from this study will be used to develop better imaging methods that will, in turn, permit a greater understanding of normal and abnormal brain behaviors. ...
Gender: All
Ages: 18 Years - 120 Years
Updated: 2026-05-29
1 state
NCT01934660
Links Between Inflammation and Cardiometabolic Diseases
Background: \- Cardiometabolic diseases are a combination of medical disorders that, when they occur together, increase the risk of heart disease and diabetes. Researchers want to learn if there is a relationship between these diseases and inflammation (redness, swelling, and pain). Inflammation affects the entire body. Researchers will study this relationship in people with heart disease and diabetes, and compare it to healthy people. Objectives: \- To learn if there are links between inflammation and cardiometabolic diseases. Eligibility: * Adults 18 years of age or older with heart disease or diabetes. * Healthy volunteers 18 years of age or older. Design: * Participants will have up to six study visits. There will be first visit, then an optional visit 12 months after the first visit. * At the study visits they will have: * Blood taken with a needle in their arm. * An electrocardiogram. Small patches are stuck to the chest and limbs. A machine measures electrical signals of the heart. * Completed a number of questionnaires. * A body scan called an FDG PET/CT. A substance will be injected through a tube in their arm. They will lie on a special bed that will move in and out of the PET/CT scanner. The PET/CT scanner will take pictures of the body. The scan will last up to 30 minutes. * Some participants will have other body scans ( FDG PET/MRI). The procedures are similar to the FDG PET/CT scan. These other scans will last about 30 minutes total. * Some participants will also have a CT scan of their heart. A substance will be injected through a tube in their arm. They will lie on a table in a large, donut-shaped machine. An X-ray tube will move around their body, taking many pictures. This procedure can last up to 2 hours. * Some participants will have tests that measures blood pressure and how the blood moves through the body. * Some participants will have small samples of skin and fat tissue taken.
Gender: All
Ages: 18 Years - 100 Years
Updated: 2026-05-29
1 state
NCT07566468
Role of Theta Frequency Oscillations in Proactive and Reactive Control Processes in Youth With Attention Deficit Hyperactivity Disorder (ADHD) and Obsessive Compulsive Disorder (OCD)
Background: Attention deficit hyperactivity disorder (ADHD) is common in children. It can cause problems with attention and the ability to control actions and impulses. Obsessive compulsive disorder (OCD) is less common in children but not rare. It involves ongoing thoughts, urges, impulses, and repeated behaviors. Researchers want to study differences in brain activity between healthy children, those with ADHD, and those with OCD. Objective: To learn more about how the brain controls thinking and behavior. Eligibility: People aged 12 to 17 years with ADHD, OCD, or neither. Design: Participants will have 3 to 10 clinic visits in up to 1 year. Each visit will last 2 to 3 hours. Three visits are required: Behavioral. Participants will complete a computer task. Their mood, memory, attention, and thinking skills will be tested. EEG. Participants will undergo electroencephalography (EEG) to measure signals in their brain. Small electrodes will be placed on the scalp. A cap will be stretched over the head. Signals will be recorded while participants rest or do tasks on a computer. MRI. Participants will have a magnetic resonance imaging scan (MRI). They will lie on a table that rolls into a tube. The MRI will take pictures of their brain while they do tasks on a computer. Seven more visits are optional. These include 2 more EEG visits and 2 more MRI visits. Three will be magnetoencephalography (MEG) visits: MEG measures small magnetic field changes in the brain. A helmet with sensors will be placed on the head. Brain changes will be recorded while participants rest or do tasks on a computer.
Gender: All
Ages: 10 Years - 17 Years
Updated: 2026-05-29
1 state
NCT06690294
Assessing the Impact of Perceptions of Unpredictability on Objective Measures of Food Consumption and Metabolism
Background: Many people in the United States are overweight or obese. This natural history study will look into how life events during childhood can impact eating behaviors and weight gain as adults. Objective: To explore how childhood experiences affect adult eating behaviors. Eligibility: Healthy people aged 18 to 60 years. Design: Participants will have 3 clinic visits. They will be screened with blood tests. They will answer questions about their alcohol and tobacco use. At the next visit, participants will undergo these activities: Parts of their body (such as waist, neck, and thighs) will be measured with a tape. They will have an imaging scan to find out how much body fat they have. They will start wearing a device like a wristwatch that measures their physical activity. They will wear this device for up to 10 days. They will wear a device on their upper arm or belly that measures blood glucose (sugar) levels. Participants will wear this for 7-10 days. They will answer questions about their education, childhood, and routines. They will receive a kit to collect a stool sample at home. At the last visit, participants will have these tests: Participants will relax and breathe normally while wearing a clear, plastic canopy that fits over their entire head. Blood samples will be taken before and after participants drink a sugary drink. Participants will be offered a large selection of foods for lunch. They will eat as much as they want. Then they will answer questions about how they feel about food and themselves.
Gender: All
Ages: 18 Years - 60 Years
Updated: 2026-05-29
1 state
NCT06989320
Endogenous Oxalate Synthesis in Idiopathic Calcium Oxalate Kidney Stone Disease
The goal of this clinical trial study is to test if patients with idiopathic calcium oxalate kidney stones have an increased production of oxalate by the body, which would lead to increased urinary excretion of oxalate. The study will recruit adult patients with a history of calcium oxalate kidney stones and healthy volunteers without kidney stones. Participants will ingest fixed diets containing low amounts of oxalate for 5 days ingest a soluble form of glycolate and vitamin C collect urine, blood, stool during the dietary and oral dosing portions of the study and also collect breath sample during the oral glycolate test
Gender: All
Ages: 18 Years - 80 Years
Updated: 2026-05-29
2 states
NCT06274749
Effects of Urolithin A Supplementation on Glucose Metabolism in Healthy Adults 55 >= Years Old: A Randomized Triple-Masked Controlled Clinical Trial
Background: As people age, the cells in the pancreas that produce insulin begin to release less of this hormone, and levels of blood glucose (sugar) rise. This can lead to illnesses such as diabetes. Urolithin A (UA) is a natural nutritional supplement that may improve how the body controls blood glucose. Objective: To learn if UA improves levels of insulin and other hormones that help control blood glucose. Eligibility: People aged 55 years and older with a body mass index of 27 or higher. Design: Participants will have 6 clinic visits over 8 weeks. Participants will be screened. They will have a physical exam with blood and urine tests and a test of their heart function. UA gelcaps are taken by mouth every morning at home. Half of participants will take UA. The other half will take a placebo. The placebo looks like the study drug but does not contain any medicine. Participants will not know which they are taking. Participants will have tests during the study including: Oral glucose tolerance: Participants will drink a sweet liquid. Blood will be drawn at intervals over the next 3 hours. Continuous glucose monitor: A sensor with a needle that goes just under the skin will be placed on the upper arm. Participants will wear this sensor throughout the study. Exercise. Participants will walk on a treadmill while their heart rate, hearth rhythm, and blood pressure are monitored. They will walk in a hallway at normal and fast paces. Imaging scans of the thigh; scans of the brain are optional....
Gender: All
Ages: 55 Years - 100 Years
Updated: 2026-05-29
1 state
NCT05652478
Early Metabolic Effects of Antiretroviral Drugs in Healthy volUnteers: a Phase 2 Randomized Study
Background: People with HIV take drugs to keep the amount of virus in their body low. One type of these drugs, called integrase strand transfer inhibitors (INSTIs), can cause weight gain over time. Weight gain can cause diabetes, heart disease, and other serious issues. Researchers want to understand how INSTIs cause weight changes. Objective: To characterize the change in plasma metabolite profile that 4 weeks of each treatment may induce in the absence of HIV infection Eligibility: Healthy people aged 18 to 55. Design: Participants will be screened in the outpatient clinic. They will have a physical exam and blood tests. They will have a nutritional assessment and tests of their heart function. Participants will be randomized to one of four oral treatments: Tenofovir Disoproxil Fumarate TDF/Viread, Tenovovir Alafenamide TAF/Vemlidy, Dolutegravir DTG/Tivicay, or both TAF and DTG taken together for 4 weeks. Participants will have a Day 0 visit for the Lead-In Baseline visit for an exam and blood tests and continuous glucose monitor placement. Participants will return in 2wks or Day 14/Wk 2 for a DEXA (dual-energy X-ray absorptiometry). DEXA is a kind of X-ray that measures body fat and bone density. Optional adiopse (fat) tissue biopsy in the abdomen, and optional microbiome specimen collections. Continuous glucose monitor changed. Oral once a day dose medication will be started with education. Participants will return in 2wks or Day 28/Wk 4 for exam, labs, and continuous glucose monitor changed. Participants will return in 2wks or Day 42/Wk 6 for final exam, labs, repeat DEXA scan, repeat adipose tissue biopsy, and microbiome specimen collections.
Gender: All
Ages: 18 Years - 55 Years
Updated: 2026-05-29
1 state
NCT01266577
Development of Magnetic Resonance Spectroscopic Imaging Techniques for Imaging Metabolites in Human Brain and Muscle
Background: \- Magnetic resonance imaging (MRI) is a widely used scanning technique to obtain images of the human body and evaluate activity in the brain. A particular MRI method called magnetic resonance spectroscopy (MRS) can be used to study brain chemistry as well, which may help researchers who are studying new treatments for psychiatric illnesses. Researchers are interested in improving current MRI and MRS techniques, as well as developing new MRI and MRS techniques to view and measure brain chemicals and brain activity. Objectives: \- To implement, develop, and optimize brain chemistry imaging techniques using magnetic resonance imaging and magnetic resonance spectroscopy. Eligibility: \- Healthy individuals between 18 and 65 years of age. Design: * This study will involve a screening visit and a scanning visit at the National Institutes of Health Clinical Center. * Participants will be screened with a full medical and physical examination, blood and urine tests, and neurological testing. * During the second visit, participants will have an MRI scan of the brain. (Participants who have received an MRI within the past year will not need to have a second one; the images of the previous scan will be used for this study.) All participants will then have an MRS scan using the same scanning equipment.
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-05-29
1 state
NCT07570147
A Study to Evaluate the Pharmacokinetics, Safety, and Tolerability of Single Ascending Doses of ABBV-1451 Infusions and Injections in Healthy Adult Participants
The objective of this study is to assess the pharmacokinetic (PK), immunogenicity, safety, and tolerability of ABBV-1451 after single ascending doses in healthy adult volunteers.
Gender: All
Ages: 18 Years - 60 Years
Updated: 2026-05-28
1 state
NCT07253246
ENX-205 SAD/PET Study in Healthy Adults
This is a two-part study designed to evaluate the safety, tolerability, pharmacokinetics (PK), and receptor occupancy (RO) of ENX-205 in healthy adult participants in a double-blind placebo-controlled, single ascending dose (SAD) study (Part 1) and an open-label, single-dose, positron emission tomography (PET) study (Part 2).
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-05-28
1 state
NCT07554365
A Trial to Assess Safety, Tolerability, and Pharmacokinetics of AN01 Inhalation Powder in Healthy Participants
AN01 is a selective small-molecule dual inhibitor of phosphodiesterase 3 and 4 (PDE3/4). As a potential new therapy for COPD, AN01 is expected to serve either as a monotherapy for COPD or as adjunctive therapy to current inhaled standard treatments, potentially generating synergistic complementary effects in patients requiring additional therapeutic options. The primary objective of this study is to evaluate the safety, tolerability, and pharmacokinetics of multiple doses of AN01 in healthy participants.
Gender: All
Ages: 18 Years - 60 Years
Updated: 2026-05-28
1 state
NCT06819189
Role of Metal Ion Transporter ZIP8 in Alcohol-Related Behaviors
Background: Alcohol use disorder (AUD) can damage people s health, work, and family. Researchers want to know more about why some people are more vulnerable to AUD than others. The ZIP8 gene may be linked to an increased risk of AUD. Researchers want to find out how different forms of the ZIP8 gene affect how healthy people drink alcohol and how alcohol affects their brain. Objective: To study how genes may affect how people drink alcohol and how it affects their brain. Eligibility: Healthy people aged 21 to 60 years. They must not smoke, and they must have no history of AUD. They must have European ancestry and be enrolled in Natural History Protocol (14-AA-0181). Design: Participants will have 2 study visits. At the first visit, participants will be given alcohol; it will be infused through a tube attached to a needle inserted into a vein. They may self-administer each dose by pressing a button. Over time, they will have to press the button an increasing number of times to receive more alcohol. The infusion period will last 2.5 hours. Participants will have blood samples taken and breath measurments, and they will do computer tasks and complete questionnaires during and after the infusion. After the infusion, they will remain in the clinic until their breath alcohol levels drop to a safe level. At the second visit, participants will have an imaging scan of their brain. They will do tasks and play games on a computer screen during the scan. Some participants may have an extra visit for screening. A mid-study visit may also be needed if more than 6 months pass between the 2 study visits....
Gender: All
Ages: 21 Years - 60 Years
Updated: 2026-05-28
1 state
NCT07600762
A Study to Assess Adverse Events, Tolerability and How a Single Oral Dose of Nacresertib Moves Through the Body In Healthy Adult Japanese Participants
A Study to Assess Adverse Events, Tolerability and How a Single Oral Dose of Nacresertib Moves Through the Body In Healthy Adult Japanese Participants
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-05-26
1 state
NCT06500793
Single Dose Study, Pharmacokinetics of Oxycodone and PF614 Co-Administered With Nafamostat (PF614-MPAR-102)
A single dose dose study to assess the pharmacokinetics (PK) of oxycodone, when PF614 is administered alone and with nafamostat as an immediate-release (IR) solution and/or extended-release(ER) capsule prototypes.
Gender: All
Ages: 18 Years - 55 Years
Updated: 2026-05-26
1 state
NCT06741657
A Study to Find Out How Litifilimab is Processed in the Body in Healthy Participants When Given Under the Skin in 3 Different Ways
In this study, researchers will learn how the body processes litifilimab when it is given under the skin in 3 different ways. Currently, ongoing studies utilize pre-filled syringes (PFS) that can deliver litifilimab subcutaneously (SC), also known as under the skin. In this study, researchers want to learn more about new ways of delivering litifilimab SC using either an autoinjector (AI) or an on-body injector (OBI): Both devices are designed to deliver litifilimab in an automatic way, especially helping patients who may not be able to use their hands very well, or who may be afraid of needles. While the AI is handheld, the OBI device works by being placed on the skin and can help deliver the highest amount of litifilimab through a single injection. The main objective of this study is to learn how the body processes litifilimab after using the AI device or the OBI device, as compared to using the PFS method. The main questions researchers want to answer are: * What is the highest amount of litifilimab found in the blood after dosing? How much total litifilimab is found in the blood throughout the study? Researchers will also learn more about: Any medical problems the participants have during the study * Any injection site pain or reactions the participants may have. Any skin reactions to the OBI device * Any changes in the participants' overall health after receiving litifilimab. This study will be done as follows: * Participants will be screened to check if they can join the study. The screening period will be up to 4 weeks, after which selected participants will check into their study research center. * Participants will be randomly assigned to be in Part 1 or Part 2 of the study: * Part 1: Participants will receive SC injection(s) of litifilimab through either the AI device or through PFS. * Part 2: Participants will receive SC injection(s) of litifilimab through the OBI device or through PFS. * Participants will remain at their study research center for the first 8 days. After that, there will be a follow-up period for 17 weeks during which participants return to the center a total of 6 times. Each participant will be in the study for about 22 weeks.
Gender: All
Ages: 18 Years - 55 Years
Updated: 2026-05-26
2 states
NCT00090662
Collection of Data and Samples From Healthy Donors for Use in Translational Research
Increased numbers of white blood cells called eosinophils can cause disease. To investigate this disease, researchers need blood, urine, sputum, stool, cerebrospinal fluid, skin and/or bone marrow samples to compare to samples from patients with this problem. Some of the samples will be used for genetic testing or future research. This study will last for about 10 years and will include a maximum of 50 paid volunteers ages 18 to 65.
Gender: All
Ages: 18 Years - 85 Years
Updated: 2026-05-22
1 state
NCT00001367
Diagnosis and History Study of Patients With Different Neurological Conditions
This protocol is a screening and natural history protocol, which allows for evaluation of patients and families where neurological conditions are present for enrollment into other studies and will also be used to screen healthy volunteers to create a pool of potential future HV matches for HMCS protocols. Through diagnostic evaluations, data will be collected for research use in this study.
Gender: All
Ages: 2 Years - 100 Years
Updated: 2026-05-22
1 state
NCT01568697
Oral Bacteria and Immune System Problems Involved in Gum Disease (Periodontitis)
Background: \- Gum disease is a condition in which the tissue around the tooth root becomes swollen and infected. This condition can cause tooth loss if it is not treated. Who gets gum disease and how bad it will be depends on (1) the different bacteria in the mouth and (2) how the immune system of an individual handles these bacteria. Researchers want to look at the oral bacteria and genetic immune problems of different people to learn how these affect gum disease and other conditions of the mouth. Objectives: \- To study how immune system problems may lead to problems in the mouth, including gum disease. Eligibility: * Children and adults at least 7 years of age who have genetic problems with their immune system. * Healthy adults that have periodontal disease * Health adults that do not have periodontal disease Design: * This study will involve a screening visit and a study visit. * Participants will be screened with a medical history, blood work and a full oral and dental exam, including dental x-rays and photos. * The study visit will involve collection of blood, urine, and other samples, including saliva, plaque, and gum swabs. Any abnormal tissue will sampled for a biopsy. Additional oral and dental exams will be performed. Participants will also answer questions about any current medical or dental problems.
Gender: All
Ages: 7 Years - 100 Years
Updated: 2026-05-22
1 state
NCT00001505
The Acquisition of Blood and Skin Samples From Normal Volunteers to Support Research Activities on Dermatologic Diseases
Background: -This protocol is concerned with the acquisition of blood, skin, or mucosal samples from healthy volunteers or patients with selected skin diseases to support the basic science and clinical research activities of the Dermatology Branch and other intramural Laboratories and Branches at the NIH Clinical Research Center. Objectives: (Primary) -To allow collection of blood, skin, or mucosal samples from healthy volunteers or patients with selected skin or systemic diseases as needed to support the research activities of our Branch and other Laboratories and Branches. Eligibility: * Healthy individuals (including employees and other patients) and patients with selected skin or other diseases, including individuals of both genders and all racial/ethnic groups. * Patient volunteers must be willing to undergo blood drawing and/or skin/mucosal biopsies. Design: -This is dependent upon the particular investigation for which these samples are needed.
Gender: All
Ages: 18 Years - 100 Years
Updated: 2026-05-22
1 state
NCT00001360
Studies of Blood Flow to the Brain During Thought
The purpose of this study is to use brain imaging technology to measure changes in blood flow to areas in the brain as individuals perform intellectual tasks. This study will use functional magnetic resonance imaging (fMRI) to examine blood flow to areas of the brain as participants engage in tasks associated with visual perception, visual recognition, and memory.
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-05-22
1 state
NCT06739707
Subcutaneously Administered MD-18 for the Treatment of Obesity and Diabetes
A Multiple Dose, Randomized, Placebo-controlled, Dose-escalating Study to Evaluate Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Subcutaneously Administered MD-18 for healthy subjects with overweight or obesity
Gender: All
Ages: 18 Years - 70 Years
Updated: 2026-05-20
1 state