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Clinical Research Directory

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91 clinical studies listed.

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Healthy Subjects

Tundra lists 91 Healthy Subjects clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.

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NOT YET RECRUITING

NCT07872579

Mass Balance Study of [¹⁴C]FXS4640 in Healthy Adult Males

A Single-center, Non-randomized, Open-label, Single-dose Mass Balance Study of \[14C\]FXS4640 in Healthy Adult Male Participants

Gender: MALE

Ages: 18 Years - 45 Years

Updated: 2026-10-13

1 state

Healthy Subjects
RECRUITING

NCT07782593

Satiety, Microbiome, Appetite Regulation, and Tracking Energy Across Targeted Snacks: Chronic Study

The goal of this clinical trial is to learn how eating different snack foods affects long term hunger and gut health in healthy adults. The study will be conducted remotely over 7 weeks. The main questions it aims to answer are: 1. Does eating a snack bar intervention for 5-weeks change how hungry participants feel throughout the day compared to a control? 2. Does eating a snack bar intervention change gut microbiome, bowel habits, digestive symptoms, and other health measures compared to a control over 5 weeks? Researchers will compare an intervention snack bar to a control snack bar to see if the intervention improves hunger, gut microbiome, digestive symptoms and other health measures. Participants will: * Eat 2 snack bars in place of their usual snacks every day for 4 weeks * Complete health measurements at the start and end of the study: a health questionnaire, 3-day food diary, 3-day hunger \& satiety survey, body measurements, and a stool sample * Fill out a short online survey (under 5 minutes) once a week

Gender: All

Ages: 35 Years - 65 Years

Updated: 2026-10-13

Healthy Participants
Healthy Adult Subject
Healthy Subjects
+2
COMPLETED

NCT00001258

Studies of Frontal Lobe Brain Functioning in Schizophrenia

The purpose of this study is to use brain imaging technology to investigate the role of the frontal lobe of the brain in the thinking of individuals with schizophrenia and other neuropsychiatric disorders and healthy volunteers. Participants in this study will undergo a positron emission tomography (PET) scan of the brain while performing neuropsychological tests. Some of the tests involve cognitive operations that depend upon the frontal cortex. Interactions between frontal lobe activation, cognitive behavior, and neuropharmacology will be assessed by measuring regional cerebral blood flow (rCBF) during treatment with drugs that may affect frontal lobe physiology....

Gender: All

Ages: 18 Years - 90 Years

Updated: 2026-10-13

1 state

Healthy Subjects
Schizophrenia
Parkinson Disease
RECRUITING

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: 2026-10-13

1 state

Immunosuppression
Periodontal Disease
Healthy Subjects
+1
RECRUITING

NCT07776418

Satiety, Microbiome, Appetite Regulation, and Tracking Energy Across Targeted Snacks: Acute Postprandial Study

The goal of this clinical trial is to learn how eating different snack foods affects acute hunger, energy intake and eating behaviour in healthy adults. The study will be conducted remotely over 5 days. The main questions it aims to answer are: 1. Does eating a snack bar intervention change how hungry participants feel later in the same day? 2. Does eating a snack bar intervention change participants' energy intake, nutrient intake and eating behaviour on the same day? 3. Does eating a snack bar intervention change participants mood, energy levels and alertness later in the same day? Researchers will compare an intervention snack bar to a control snack bar to see if the intervention improves hunger, energy intake, eating behaviour, and other subjective measures. Participants will: * Eat 2 snack bars for breakfast on 2 separate days, with 2 days in between * Not eat anything after 9pm the night before each test day * Fill out short online surveys (under 5 minutes) before breakfast and at set times over the next 3 hours * Not eat for 3 hours after breakfast * Write down everything they eat that day

Gender: All

Ages: 35 Years - 65 Years

Updated: 2026-10-07

Healthy Participants
Healthy Adult Subject
Healthy Subjects
+2
TERMINATED

NCT06315725

Effect of Artificial Sweetener (AFS) on Glucose Metabolism in Patients With Type 1 Diabetes (T1D)

The goal of this randomized crossover study is to test the prediction that consuming carbohydrates will affect insulin release differently depending on whether Non-Nutritive Sweeteners (NNSs) are consumed simultaneously. We aim to determine whether the predicted effects are associated with oral or post-oral sweet taste receptor signaling,. Our study will focus on patients diagnosed with type 1 diabetes (T1D) who are using an artificial pancreas (AP) system, as it allows us to monitor glucose and insulin levels over time. Participants will drink four different flavored beverages, some with sweet taste blockade and some without, in a counter-balanced order. They will then rate the sweetness of each beverage, and we will collect data from their AP system to monitor insulin and glucose level. To achieve this, we will conduct a pilot study to assess the effectiveness and best timing of sweet taste blockade in healthy individuals. Insights gained from the pilot study will inform the main study. Sucralose will be used as the NNS, maltodextrin as the carbohydrate, and Gymnema Sylvestre (GS) as the sweet taste receptor blocker.

Gender: All

Ages: 18 Years - 45 Years

Updated: 2026-10-06

1 state

Type 1 Diabetes (T1D)
Healthy Subjects
NOT YET RECRUITING

NCT07856706

A Single Ascending Dose, and Food Effect Study of ABBV-7828 in Healthy Adults

This study is to evaluate safety, tolerability, pharmacokinetics and effect of food on ABBV-7828 compared to placebo in healthy adult participants.

Gender: All

Ages: 18 Years - 65 Years

Updated: 2026-10-05

1 state

Healthy Subjects
COMPLETED

NCT07856446

ABVN Phase 2 - PENFS

The vagus nerve is a nerve that controls many bodily functions, including stomach function. Investigators hope that electrically stimulating the nerve around the external ear will also stimulate the internal vagus nerve. If it does, then investigators hope that this may lead to additional treatment options for patients with nausea and vomiting and disordered stomach function. The overall purpose of the ABVN Phase 2 grant is to expand on previous work evaluating the effects of noninvasive stimulation on vagal nerve function. This will be accomplished through several independent, but related, studies. In this study, investigators will evaluate the effect of percutaneous electrical field stimulation on the vagus nerve in healthy subjects. \[This study was originally described in NCT06491758, however a separate record has been created to more accurately reflect the independence of the individual studies supported by the ABVN 2 grant.\]

Gender: All

Ages: 18 Years - 80 Years

Updated: 2026-10-02

1 state

Healthy Subjects
COMPLETED

NCT02777268

Comparison of Pharmacokinetics of Infacort® Versus Immediate-release Hydrocortisone

This was a single centre, open-label, randomised, 5-way crossover study.

Gender: MALE

Ages: 18 Years - 60 Years

Updated: 2026-10-02

Healthy Subjects
COMPLETED

NCT02610465

High Image Matrix CT Reconstruction

Background: Computed Tomography (CT) scans make detailed pictures of the body in seconds. CT scans make pictures by passing x-rays through a person. CT scans are common. In 2011, around 85.3 million of them occurred in the United States. Researchers think CT images can be made better using new techniques. Higher resolution images can be derived from the original scan. Objective: To learn if new ways of obtaining and processing pictures of the body from a regular CT scan can produce images with higher resolution (pixels) and more information than standard methods. Eligibility: People ages 18 and older who are scheduled to have a CT scan and are not pregnant Design: Participants will be screened with a review of their medical records. Participants will have their scheduled CT scan. The CT scanner used in this study provides enhanced images of inside the body. Researchers may use the CT scanner in a research mode to test and improve the pictures. Images from the CT scan will be reviewed. Any clinical findings from the CT test will be shared with the participant s doctor. Participants will continue to receive their medical care from their regular doctor. The CT images will be entered into an NIH research database. In the future, they may be used for research purposes.

Gender: All

Ages: 18 Years - 99 Years

Updated: 2026-10-02

1 state

Healthy Subjects
Pulmonary-Related Conditions
Cardiac-Related Conditions
RECRUITING

NCT07428785

Pulmonary and Total Blood Volume in COPD

Background Patients with chronic obstructive lung disease (COPD) suffer from a progressive loss of lung function that leads to poor quality of life, and often invalidity and early death. This is markedly affected by a reduced exercise capacity and dyspnoea, but the underlying mechanisms are unknown. In the present study, we aim to investigate whether this may involve a reduced pulmonary blood volume secondarily to a reduced total blood volume. Methods Design: Prospective matched comparative study Intervention: None Outcomes: The primary outcome is pulmonary blood volume estimated to total blood volume ratio between patients with COPD and healthy controls individually matched for age, sex, and height. Statistical design: All statistical analyses will be performed using R statistical software version 4.1.1 (R Project for Statistical Computing) within RStudio statistical software version 1.4.1717 (RStudio), and a two-tailed p\<0.05 will be considered statistically significant. Inspection of normality and variance homogeneity will be done by creating qq-plots and histogram. Regulatory considerations: This study will be submitted for approval by Regional Ethical Committee. Perspective: This study will help uncover fundamental aspects of the pathophysiology of COPD.

Gender: All

Ages: 45 Years - 80 Years

Updated: 2026-10-02

COPD (Chronic Obstructive Pulmonary Disease)
Healthy Subjects
COMPLETED

NCT07856459

ABVN Phase 2 - EDS Wearable Device

The vagus nerve is a nerve that controls many bodily functions, including stomach function. Investigators hope that electrically stimulating the nerve around the external ear will also stimulate the internal vagus nerve. If it does, then investigators hope that this may lead to additional treatment options for patients with nausea and vomiting and disordered stomach function. The overall purpose of the ABVN Phase 2 grant is to expand on previous work evaluating the effects of noninvasive stimulation on vagal nerve function. This will be accomplished through several independent, but related, studies. In this study, investigators will evaluate autonomic responses in Ehlers-Danlos Syndrome patients and healthy participants during transcutaneous electrical stimulation of the vagus nerve and during normal daily activities.

Gender: All

Ages: 18 Years - 80 Years

Updated: 2026-10-02

1 state

Ehlers-Danlos Syndrome
Healthy Subjects
RECRUITING

NCT02417714

Prospective Evaluation of Next Generation CT Reconstruction (NextGenIR)

Background: \- Computed Tomography (CT) is a scan that makes detailed pictures of the body. It uses radiation to do that. In 2011, about 85.3 million CT scans were done in the United States. But there is growing concern about the health effects of radiation. There are new and different ways to make CT pictures that use less radiation. Researchers want to learn whether these new methods create images that are similar to images from a traditional CT. Objective: \- To learn if new CT imaging methods with less radiation make images that are similar to traditional ways. Eligibility: \- Adults 18 years of age and older who are scheduled for a CT of the chest, abdomen and pelvis with contrast. Design: * Researchers will review participants medical records to see if they can be in this study. * Participants may have blood drawn from an arm vein by a needle stick. The blood will be used to make sure they can be in this study and that it is safe for them to have contrast. * During the participants CT scan appointment, one extra scan will be done using low radiation methods. * During a CT scan, the participant lies on a table. A large x-ray machine takes pictures of the body.

Gender: All

Ages: 18 Years - 99 Years

Updated: 2026-10-02

1 state

Healthy Subjects
COMPLETED

NCT07584304

Bioequivalence Study Between YHP2508C and YHR2603 in Healthy Subjects

An open-label, randomized, fasting, single-dose, oral administration, 2-sequence, 4-period, replicate crossover study to evaluate bioequivalence between YHP2508C and YHR2603 in healthy subjects

Gender: All

Ages: 19 Years - 54 Years

Updated: 2026-10-01

1 state

Healthy Subjects
ACTIVE NOT RECRUITING

NCT03029806

Lysine-specific Demethylase 1 and Salt-sensitivity in Humans

The purpose of this study is to investigate the role dietary salt plays in epigenetic regulation of blood pressure, focusing on the salt-sensitive regulatory enzyme Lysine-specific demethylase 1.

Gender: All

Ages: 25 Years - 45 Years

Updated: 2026-09-29

1 state

Healthy Subjects
RECRUITING

NCT07395609

High Frequency Stimulation to Improve Cognition, Mobility, and Affect in Individuals With and Without Subjective Cognitive Decline

The goal is to determine whether three months of at least three times / week of sensory flicker stimulation improves cognition, mobility, and affect in healthy older adults and older adults with and without Subjective Cognitive Decline (SCD). Investigators will also determine whether the intervention slows cortical thinning and declines in brain functional network segregation and changes in blood biomarkers of Alzheimer's Disease (AD).

Gender: All

Ages: 65 Years - 89 Years

Updated: 2026-09-23

1 state

Subjective Cognitive Decline (SCD)
Healthy Subjects
RECRUITING

NCT07015437

A Recovery and Lifespan Study Using INTERCEPT Red Blood Cells Prepared Using the INTERCEPT Blood System for RBCs With AS-1

The objective of this trial is to assess the post-infusion viability of INTERCEPT RBCs by measuring the 24-hour post-infusion recovery and lifespan of autologous RBCs prepared with the INTERCEPT Blood System for RBC with AS-1 after 35 days post collection storage in comparison to untreated AS-1 RBCs stored for 35 days.

Gender: All

Ages: 18 Years - Any

Updated: 2026-09-21

2 states

Healthy Subjects
COMPLETED

NCT07218120

In-Person Recruitment of Individuals to the Alzheimer's Prevention Trial (APT) Webstudy

Women, older adults, individuals from communities of color, particularly Black and Latino persons, and individuals with lower socioeconomic status are historically underrepresented in clinical research. This is true across a range of clinical areas but no more so than in Alzheimer's Disease Research. The purpose of this study is to assess whether offering small $25 financial incentives can increase enrollment of diverse community members to the Alzheimer's Prevention Trial (APT) Webstudy, a memory concerns registry meant to accelerate clinical trials, relative to non-monetary incentives such as a reusable grocery bag. To do this we will test in-person recruitment efforts at community events and locations, such as Northgate Gonzalez Market locations and local food bank events. We also aim to compare the relative cost of recruiting an additional person to the APT Webstudy.

Gender: All

Ages: 50 Years - Any

Updated: 2026-09-15

1 state

Memory Decline
Healthy Subjects
RECRUITING

NCT07222020

Phase 1 Study of Intravaginal KB15A

The goal of this clinical trial is to determine the safety and mucosal pharmacokinetics of KB15A, a vaginal film containing an anti-sperm monoclonal antibody, in healthy adult women. Researchers will compare KB15A use to placebo use, primarily to see if KB15A is associated with adverse events, and also to understand the local and systemic distribution of the KB15A monoclonal antibody following use of the vaginal film. Participants will be assessed for the genital, mucosal and systemic safety and pharmacokinetics of KB15A in a preliminary single-dose phase of the study, where they will receive two single doses of either KB15A or placebo vaginal film, and again in a multiple-dose phase of the study, where they will receive 14 daily doses of either KB15A or placebo vaginal film.

Gender: FEMALE

Ages: 18 Years - 45 Years

Updated: 2026-09-14

1 state

Healthy Subjects
RECRUITING

NCT06014515

Single-tracer Multiparametric PET Imaging

The overarching goal of this project is to develop and evaluate a single-tracer multiparametric positron emission tomography (PET) imaging solution for simultaneous imaging of blood flow and glucose metabolism using 18F-fluorodeoxyglucose (FDG) alone. The investigators working hypothesis is that quantitative blood flow can be extracted from dynamic 18F-FDG PET data by use of tracer kinetic modeling, in addition to glucose metabolism that 18F-FDG is conventionally used for.

Gender: All

Ages: 18 Years - Any

Updated: 2026-09-14

1 state

Healthy Subjects
Cardiovascular Disease
COMPLETED

NCT00756080

"Effects of Oral Citrulline on Protein Metabolism in Healthy Humans: a Prospective, Randomized, Double-blind , Cross-over Study" (Citrugrêle)

The specific aim of this study is to determine whether oral citrulline administration enhances whole body protein synthesis in healthy humans in the postabsorptive state. Protein metabolism will be assessed using an intravenous infusion of stable isotope labeled leucine. The investigators hypothesize that citrulline supplementation will decrease leucine oxidation without altering proteolysis, and consequently stimulate protein synthesis .

Gender: All

Ages: 18 Years - 45 Years

Updated: 2026-09-14

Healthy Subjects
NOT YET RECRUITING

NCT07818330

A Repeat Dose Study of the Dexmedetomidine Transdermal System in Healthy Subjects

This Phase 1, 16-day Repeat dose study will evaluate the safety of a Dexmedetomidine Transdermal System (DMTS) skin system in healthy adults Subjects. Participants will receive the patch for four consecutive 4-day treatment periods. Researchers will monitor safety, drug levels in the blood, sedation effects, skin irritation, and how well the patch stays attached to the skin.

Gender: All

Ages: 18 Years - Any

Updated: 2026-09-14

Healthy Subjects
RECRUITING

NCT07181369

A Phase 1 Study of GTX-B001 in Healthy Subjects and Patients With Chronic Inducible Urticaria

This is a first-in-human study aimed at determining the safety of a single dose of GTX-B001 in healthy participants and in people with chronic inducible urticaria.

Gender: All

Ages: 18 Years - 75 Years

Updated: 2026-09-09

Healthy Subjects
Cold Urticaria
Symptomatic Dermographism
+1
RECRUITING

NCT07232459

[18F]FT8 PET Imaging in Immunoglobulin Light Chain Amyloidosis

\[18F\]FT8, a derivative of 1-(4-pyridyl)-4-piperazinyl arene (\[18F\]TPZA), exhibits high affinity for AL amyloid in myocardial tissue sections and shows no significant binding to transthyretin amyloid. By comparing its diagnostic performance against established clinical methods, including echocardiography, contrast-enhanced MRI, and relevant laboratory tests, this study aims to establish \[18F\]FT8 as the basis for a robust PET protocol for the direct visualization and differential diagnosis of AL amyloidosis . The study preimarily evaluates the safety and diagnostic efficacy of \[18F\]FT8 PET imaging in human subjects.

Gender: All

Ages: 18 Years - Any

Updated: 2026-09-08

3 states

Amyloid
Cardiac Amyloidosis
Amyloidosis
+1