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53 clinical studies listed.
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Tundra lists 53 Healthy Adults clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.
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NCT07605520
An Experimental Medicine Multicenter Trial to Evaluate the Safety and Immunogenicity of Experimental Versus Authorized SARS-CoV-2 Vaccine Candidates as a Booster Dose in Healthy Participants Previously Vaccinated With Authorized mRNA SARS-CoV-2 Vaccines.
The SOLVE-01 trial is a study evaluating four SARS-CoV-2 vaccines as booster injections: two experimental vaccines (CD40.RBDv and CD40.Pan.CoV, both combined with the Hiltonol® adjuvant) and two authorised vaccines (Comirnaty® and NuvaxovidTM). This trial is designed for healthy adults aged 18 to 65 at the time of signing the informed consent form. The main objectives of this trial are: * to evaluate the safety of the two experimental vaccines, * to determine the antibody response induced by the vaccines and its durability. Participants will: * Receive one injection of vaccine and two intradermal skin tests * Come to the hospital 10 visits for medical exams and blood and saliva sample collection * Keep a diary of their symptoms and the treatments taken
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-05-26
NCT07594600
The Effect of Low or High Dietary Fiber Diet on Volatile Organic Compounds in Exhaled Breath of Healthy Individuals
The aim of this crossover intervention study is to evaluate the volatile organic compounds (VOCs) present in participants at baseline and how these levels change after consuming either a low- or high-dietary fiber diet for three days. This study will involve adults, 18-65 years old, without any gastrointestinal diseases. The primary objectives are to characterize baseline VOC profiles, assess changes in these profiles after a short-term dietary fiber intervention, determine if specific VOC patterns correlate with dietary fiber intake, and identify the time points at which VOC levels peak. This information will help establish the optimal timing for breath sampling and potentially provide insight into how VOC patterns relate to dietary fiber consumption and degradation. The expected outcome is that a high-dietary fiber diet will produce a VOC profile enriched in metabolites associated with fiber fermentation compared to a low-dietary fiber diet, and that these VOCs will be consistent with those identified in vitro during fecal fermentation. Each participant will serve as an internal control, enabling within-subject comparisons of VOC levels at baseline and following the dietary fiber intervention. Participants will receive a whole-food product that is rich in dietary fiber and will consume either a low-fiber diet (10 g/day) or a high-fiber diet (40 g/day) for three days. On the first day of each intervention, participants will also ingest a pH capsule to monitor gastrointestinal pH continuously throughout the three days. After a three-week washout period, participants will cross over to the other intervention arm and undergo another round of gastrointestinal pH monitoring. In addition to the dietary intervention, participants will complete food and health questionnaires to assess habitual fiber intake and dietary habits. Fecal samples will be collected for in vitro fermentation to functionally profile the gut microbiota by assessing fecal VOCs, short-chain fatty acids (SCFA), and the microbial enzymatic activity and its pH-dependent modulation.
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-05-26
NCT07597928
A Study to Learn How Different Forms of the Study Medicine Called PF-08049820 Are Absorbed and Eliminated in Healthy Adults
The purpose of this study is to learn how different forms of the study medicine called PF-08049820 are absorbed and eliminated in healthy adults. The study will assess whether the study medicine is absorbed differently when taken with or without food. It will also assess absorption when the study medicine is taken with another medicine called rabeprazole. Rabeprazole is an FDA approved medicine that reduces stomach acid. The study has two parts. In Part A, participants will take three forms of study medicine, one after the other. They will take each form either with or without food for a total of five doses. Each dose will be separated by a few days. Participants will stay in the clinic for about two weeks. They will receive a telephone follow-up call about a month after the last dose. In Part B, participants will take three forms of study medicine. They will take each one with or without food, and with or without another medicine called rabeprazole. This means they will take a total of six doses of study medicine. Each dose will be separated by a few days. Participants will stay at the clinic for about three weeks, and about a month after their last dose. They will get a follow-up phone call. Part B may or may not be conducted depending on the results from Part A. The study is seeking participants who: 1. Are males or females, 2. Are at least 18 years of age, 3. Have a body mass index (BMI) 16 to 32 kilograms per meter squared (kg/m2). Have a total body weight of more than 50 kilograms (kg) (110 pounds).
Gender: All
Ages: 18 Years - Any
Updated: 2026-05-20
1 state
NCT07103291
Effects of Isocapnic Respiratory Muscle Endurance Training in Healthy Adults
Respiratory muscle training (RMT) strengthens breathing muscles and may improve exercise performance and reduce breathlessness. However, different training methods and devices create controversy in the field. Two main types of RMT exist: inspiratory muscle training (IMT) and respiratory endurance training, like voluntary isocapnic hyperpnea (VIH). While IMT is well-studied, the impact of VIH on breathlessness remains unclear. This study will use the Canadian-developed BreathWayBetter device to examine how 5 weeks of VIH affects breathing discomfort and muscle function. Findings may help personalize RMT for athletes and clinical patients, improving respiratory care and exercise tolerance.
Gender: All
Ages: 18 Years - 55 Years
Updated: 2026-05-15
1 state
NCT06811545
Evaluating the Effects of an Electrical Stimulator on Improving the Walking Ability of Children With Cerebral Palsy
The goal of this study is to see if gentle electrical stimulation can help children with cerebral palsy (CP) walk more easily. This stimulation, called neuromuscular electrical stimulation (NMES), sends small pulses to muscles to help them activate. Researchers will test different ways of using NMES to find out which method works best. Participants will walk on a treadmill at a comfortable speed while NMES is applied to leg muscles. The study will compare different stimulation settings to see which one helps the most.
Gender: All
Ages: 7 Years - 40 Years
Updated: 2026-05-08
1 state
NCT07431853
A Study to Learn About mRNA Vaccines Against Influenza in Adults
The purpose of this study is to learn about safety in participants taking the study vaccine (mRNA-based vaccine) and the ability of the study vaccine to trigger the body's immune response, targeting the flu virus (influenza virus). This study is seeking healthy participants 18 years of age or older. All participants in this study will receive only 1 dose in their arm, to deliver one of the experimental flu vaccines or one of the approved flu vaccines used for comparison. Participants will take part in this study for about 6 months, and participants will need to visit the study site at least 3 times. A blood sample will be taken at each of the 3 planned study visits and a swab from inside the nose will be taken at the first study visit.
Gender: All
Ages: 18 Years - Any
Updated: 2026-05-06
13 states
NCT07567261
Efficacy and Safety of Repetitive Transcranial Magnetic Stimulation and Expressive Writing for Post-Traumatic Stress
The goal of this clinical trial is to learn if a combined treatment using repetitive transcranial magnetic stimulation (rTMS) and expressive writing works to reduce symptoms of post-traumatic stress in adults. It will also study how safe this treatment is and whether the timing of rTMS changes how well it works. The main questions it aims to answer are: * Does this combined treatment lower symptoms of post-traumatic stress? * Does it work better when rTMS is given before or after expressive writing? Researchers will compare three groups to see which approach works best: * rTMS given before expressive writing * rTMS given after expressive writing * Sham stimulation (a look-alike procedure that does not provide real stimulation) Participants will: * Take part in sessions that include expressive writing about emotional experiences * Receive either real rTMS or sham stimulation * Complete questionnaires about post-traumatic stress, anxiety, depression, and mood * Have their heart rate and skin responses measured during the sessions * Be assessed before the study, after the sessions, and one month later This study includes adults aged 18 to 65 who have experienced at least one traumatic or highly stressful event and report symptoms of post-traumatic stress.
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-05-05
1 state
NCT06116838
Transcutaneous Spinal Cord Stimulation in Healthy Adults
The goal of this study is to understand how transcutaneous spinal cord stimulation (tSCS) waveform, modulation frequency, and stimulation location impact lower extremity muscle activation and participant comfort in adults without neurologic conditions.
Gender: All
Ages: 18 Years - 75 Years
Updated: 2026-04-27
1 state
NCT06570330
Adult HMO Supplementation and the Gut Microbiome
The goal of this study is to assess the impact of Layer Origin's SuperHMO prebiotic formulation on the healthy adult gut microbiome. Over the course of 30 days, intervention participants will take SuperHMO prebiotic formulation daily. Control participants will take a placebo daily. We will measure all participants\' gut microbiome using a gut health test before taking SuperHMO prebiotic or placebo and after 30 days of taking the supplement. We hypothesize that taking the SuperHMO prebiotic will improve gut health measurements such as the potential to produce short-chain fatty acids.
Gender: All
Ages: 18 Years - 40 Years
Updated: 2026-04-24
1 state
NCT07493460
Longitudinal Tracking of Bone Marrow Plasma Cell Responses to Licensed Human Vaccines
This study is being done to understand and measure how the immune system responds to and remembers different types of vaccines. To do this, four vaccines approved by the U.S. Food and Drug Administration (FDA) will be given simultaneously to participants. Participants will be volumteers who are healthy adults (18 years old or older) and willing to receive the yearly trivalent inactivated influenza vaccine (TIV), the tetanus, diphtheria, and acellular pertussis vaccine (Tdap), the nonvalent HPV (HPV) vaccine, hepatitis A virus (HAV) vaccine and undergo study procedures. Procedures will include: * medical history relevant to the study, including medications and vaccines received. * Vitals (blood pressure, pulse) and temperature * Height and weight. * Physical exams. * Receive the TIV, Tdap, HPV, and HAV vaccines. * Blood samples collected for immunologic tests and genetic analysis. * Donate bone marrow by needle aspiration at a maximum of seven visits. * Complete memory aid every evening for 7 days after vaccination Optional Procedures include: * Donate bone marrow core biopsies at the same visits * Ultrasound of lymph nodes and fine needle aspirates of lymph nodes in both arm pits at a maximum of eight separate visits There will be a screening visit and and a Day 1 where vaccinations will occur and subsequent visits at Day 8, Day 14, Day 29, Day 57, Day 121, Day 181, Day 366, Day 546, and Day 731. At each of these visits health status, vital signs and blood collection will occur. A bone marrow aspirate and lymph node aspirate will be collected at screening. The six additional bone marrow aspirates will be repeated at D29, D91, D181, D366, D546, and D731. The optional bone marrow core biopsy will also be repeated at that time. Up to seven separate visits will be scheduled for the follow-up lymph node aspirates (D29, D57, D91, D181, D366, D546, and D731) Study participation will be 24 months.
Gender: All
Ages: 18 Years - Any
Updated: 2026-04-22
1 state
NCT04677920
The Healthy Cookie Energy Study: Understanding How Healthy Cookies Affect Mitochondrial Biology
The proposed research is an intervention and feasibility pilot trial designed to determine if short-term consumption of healthy cookies made with an oil rich in linoleic acid can influence mitochondria biology in white blood cells and muscle. The hypothesis of the study is that consuming 1 healthy cookie rich in linoleic acid each day for two weeks will improve mitochondrial biology in white blood cells and muscle.
Gender: All
Ages: 18 Years - Any
Updated: 2026-04-21
1 state
NCT02841618
The Healthy Cookie Study: Understanding How Healthy Cookies Affect Fat in the Blood,
The purpose of this study is to understand how consuming healthy cookies every day for two weeks will affect different types of fat in the blood. Specifically, the overall goal of this study is to find out if the healthy cookies can increase a polyunsaturated fat called linoleic acid in plasma, red blood cells and white blood cells.
Gender: All
Ages: 18 Years - 80 Years
Updated: 2026-04-21
1 state
NCT06656338
Phase 2 Seattle Dietary Biomarkers Development Center
The Seattle Dietary Biomarker Development Center (S-DBDC) aims to advance the science of measuring dietary intake by identification and validation of dietary biomarkers that improve upon self-reported diet. To accomplish this mission, the Seattle DBDC will carry out controlled feeding studies in healthy human volunteers. Metabolomics assays will be conducted on blood and urine specimens collected during the feeding studies for biomarker identification. Stool samples will be collected and archived.
Gender: All
Ages: 18 Years - Any
Updated: 2026-04-13
1 state
NCT07518758
Acute Effect of Polyphenols Supplementation on Endothelial Function and Exercise Related Markers, in Physically Active Healthy Volunteers.
To evaluate the effect of acute polyphenols supplementation on vasodilation and related markers along with exercise related markers (notably performance, respiratory exchanges, perceived exertion), before, during and after a hypoxic moderate-intensity exercise in healthy recreative volunteers.
Gender: All
Ages: 35 Years - 55 Years
Updated: 2026-04-13
NCT07499180
A Study on Body Posture and Eye Movements During Screen Usage on Adults Aged 18 to 65 Wearing Various Types of Eyeglasses
The goal of this clinical study is to evaluate how adults aged 18 to 65 move their bodies and eyes when they use screens, with various eyeglasses. The main questions it aims to answer are : * How the behaviour between young and presbyopes is different while performing visual tasks on digital devices ? * How the behaviour while performing visual tasks changes according to different types of eyeglasses ? Participants will be asked to take part in an eye exam and do simple visual tasks on digital devices.
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-04-13
NCT07513467
3T Magnetic Resonance Neurography
The goal of this observational study is to evaluate whether optimized high-resolution MRI can better visualize very fine nerves in the cervical spine and neck region compared to standard MRI. The main question it aims to answer is: Can high-resolution MRI reliably show small nerves and potentially detect their injuries or diseases that are often invisible on conventional MRI scans? Participants will come once to Balgrist University Hospital for a one-hour visit. They will fill out a questionnaire and have a single 30-minute MRI scan of the cervical spine without contrast.
Gender: All
Ages: 18 Years - Any
Updated: 2026-04-07
NCT06133530
Human Milk Oligosaccharides (HMOs) and Gut Microbiota, Immune System in Antarctica
Human milk oligosaccharides (HMOs) are the third-most abundant component in mothers' milk and are an important prebiotic factor for the development of the gut microbiota of infants, promoting the growth of certain beneficial bacterial strains and providing protection against many bacterial and viral infections. HMOs induce immunomodulatory activity by affecting immune cell populations and functions. In a simulator of the adult human intestinal microbial ecosystem, fermentation of HMOs led to an increase of bifidobacteria in parallel with an increase in short-chain fatty acids as well as a reduction in inflammation markers, supporting the potential of HMOs to provide health benefits also in adults. Long-term stay in microgravity induces many physiological responses, including diminished immune function and impaired glucose tolerance which may lead to rather severe consequences. Similarly, hypoxia conditions as in the Concordia station, affects the immune system and may lead to impaired glucose tolerance and insulin resistance. The hypothesis is that HMOs as a prebiotic supplement will mitigate changes in immune function, glucose tolerance, lipid homeostasis, and neurotransmitter production. It is expected that HMO supplementation will * Modulate gut microbiota composition and function * Improve inflammation status * Improve immune function * Improve glucose tolerance * Improve nutritional status * Prevent changes in neurotransmitters associated with anxiety and depression. During the stay in Antarctica an HMO blend will be supplemented to the verum group of volunteers. The control group will receive a placebo. Experiment days with blood drawing, an oral glucose tolerance test, saliva sampling, and feces samples are planned once before, about every second month in Concordia, and once after return.
Gender: All
Ages: 18 Years - 65 Years
Updated: 2026-03-31
NCT07473570
A Study(Phase I)of GS3-007a Dry Suspension in Healthy Chinese Adults
This study consists of two parts: the first part is a single-dose escalating(SAD) and food effect (FE)study, and the second part is a multiple-dose (14-day) escalating(MAD) study. Both phases are designed as randomized, double-blind, dose-escalation, placebo-controlled clinical studies.
Gender: All
Ages: 18 Years - 45 Years
Updated: 2026-03-16
1 state
NCT07462715
Statins Against Bushfire Smoke
The goal of this clinical trial is to test whether statins can protect the heart and brain from the biological stress and inflammatory responses caused by breathing bushfire smoke in healthy adult volunteers aged 18-64 years. The main questions it aims to answer are: 1. Does short-term statin use (2 days) reduce bushfire smoke-induced changes in heart rate variability, blood pressure, arterial stiffness, inflammation and oxidative stress markers, and cognitive function? 2. Does long-term statin use (≥12 months) reduce bushfire smoke-induced changes in heart rate variability, blood pressure, arterial stiffness, inflammation and oxidative stress markers, and cognitive function? The study includes two streams: Stream 1:short-term statin use (2 days) where participants receive either statin tablets (80mg atorvastatin) or placebo; Stream 2: long-term statin use (≥12 months) where participants include those already taking statins (≥12 months) with statin-naïve individuals. Participants will: * Attend two 3½-hour visits to a Climate Hut, which are approximately 4 weeks apart, where they will spend 2 hours exposed to either filtered air or simulated dilute bushfire smoke (average particulate matter (PM2.5) concentration of 300μg/m\^3) in randomised order; * Have continuous heart monitoring with ECG leads and blood pressure checks every 15 minutes during each visit * Provide urine, saliva, and nose swab samples before and after each exposure, plus follow-up samples the next morning * Complete cognitive tests (reaction time, memory tasks) and postural balance measurements during exposure * Complete questionnaires about anxiety levels, symptoms, diet, and health status * Have blood samples collected and pulse wave velocity measurements (assessing arterial stiffness) immediately after each exposure session. Potential risks include time commitment, muscle pain from statins, eye irritation or throat discomfort from smoke exposure, and minor discomfort from blood collection.
Gender: All
Ages: 18 Years - 68 Years
Updated: 2026-03-10
1 state
NCT07454551
The Comparison of Different Passive Warm-Up Methods Prior to Exercise
This randomized controlled trial aims to investigate the acute effects of two passive warm-up methods-infrared heating and therapeutic massage-on vertical jump, horizontal jump, dynamic balance, static balance, and lower extremity muscle flexibility in healthy adults.
Gender: All
Ages: 18 Years - 35 Years
Updated: 2026-03-06
NCT07227259
Health Properties of Pecan Nut Consumption
The main goal of this clinical study is to see if consuming pecan nuts will result in improvements in overall body metabolism such as in blood lipids, markers of inflammation, blood pressure, cognitive performance and changes in bacteria living in the gut in adults 45 to 75 years of age. Participants will take part in two 3-month intervention periods, separated by 4-6 weeks, in random order ( a total of approximately 7 months). During one intervention period, they will include pecan nuts in their diet each day, while during the other intervention period they will avoid pecans in their diet. There will be an initial screening visit to evaluate eligibility and four study visits to the clinic. Participants will be asked to complete some questionnaires about their diet, physical and cognitive health, and provide blood and stool samples, and have their blood pressure measured.
Gender: All
Ages: 45 Years - 75 Years
Updated: 2026-02-24
1 state
NCT06815991
Phase 1a Single Ascending Dose Study of MIB-725 in Healthy Adults
This is a single center, open label (i.e. participants and study staff will not be masked to the intervention) single ascending dose study to evaluate the safety, tolerability, pharmaokinetics and pharmacodynamics of MIB-725 in community dwelling, healthy adults. Up to 4 successive groups (cohorts) of 8 subjects each will be enrolled in this trial. This study will determine the safety and tolerability of orally administered single ascending (increasing) doses (100, 200, 400, and 800 mg) of MIB-725 in healthy adults. The safety will be assessed by evaluating physical examination that includes an external eye examination, vital signs, adverse events, and changes in blood counts, EKG, urinalysis, coagulation measures, and blood chemistries, including but not limited to blood glucose, electrolytes, creatinine, liver function tests, uric acid, and creatine kinase.
Gender: All
Ages: 19 Years - 60 Years
Updated: 2026-02-19
1 state
NCT07416786
Validation of NAD+ Measurements for Human Clinical Studies
The purpose of this study is to determine nicotinamide adenine dinucleotide (NAD) levels in healthy adult subjects before and after supplementing with over-the counter nicotinamide riboside (NR) using magnetic resonance spectroscopy (MRS).
Gender: All
Ages: 18 Years - 110 Years
Updated: 2026-02-18
1 state
NCT07216781
Safety and Efficacy of Injectable Klotho Plasmid Gene Therapy in Humans
The purpose of this study is to investigate the safety and efficacy of a gene therapy for Klotho, delivered via a nonviral plasmid in healthy adult volunteers. Additionally, this study seeks to understand the cognitive and health benefits of the Klotho gene therapy.
Gender: All
Ages: 23 Years - 90 Years
Updated: 2026-02-17
2 states