Core: healthy volunteers
Phase 1 clinical trials recruiting now
Phase 1 (and early Phase 1) trials are usually the first time a medicine is studied in people. They are typically small, closely monitored, and many are run in dedicated research units, sometimes with overnight stays.
934 recruiting studiesSource: ClinicalTrials.gov, refreshed October 27, 2026How we list studies
Studies
- RecruitingHealthy volunteersPhase 1
A Clinical Trial to Evaluate the Safety and Immunogenicity of rVSV∆G-MARV-GP Vaccine in Adults in Good General Health
International AIDS Vaccine Initiative
- Location
- Washington D.C., DC + 1 other US site
- Eligibility basics
- Ages 18–50
- RecruitingHealthy volunteersPhase 1/Phase 2
Brain Network Changes Accompanying and Predicting Responses to Pharmacotherapy in OCD
Yale University
- Location
- New Haven, CT
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 1/Phase 2
Human Immune Response to Ixodes Scapularis Tick Bites
National Institute of Allergy and Infectious Diseases (NIAID)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 18–99
- RecruitingHealthy volunteersPhase 1
Inflammatory Challenge and Fear
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 1
A Clinical Study to Investigate the Safety and Immunogenicity of rVSV∆G-SUDV-GP, a Sudan Virus (SUDV) Vaccine for the Prevention of SUDV Disease in Adults in Good General Health
International AIDS Vaccine Initiative
- Location
- Washington D.C., DC + 2 other US sites
- Eligibility basics
- Ages 18–50
- RecruitingHealthy volunteersPhase 1
PET Imaging of Cyclooxygenases in Neurodegenerative Brain Disease
National Institute of Mental Health (NIMH)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 18–99
- RecruitingHealthy volunteersPhase 1
Clinical Trial to Evaluate the Safety and Immunogenicity of Hiltonol, Poly-ICLC-adjuvanted CD40.HIVRI.Env (VRIPRO) in Adult Participants Who Previously Participated in HVTN 706
National Institute of Allergy and Infectious Diseases (NIAID)
- Location
- San Francisco, CA + 3 other US sites
- Eligibility basics
- Ages 18–60
- RecruitingHealthy volunteersPhase 1
Effects of Various Cannabis Strains on Perceptual, Subjective and Objective Use Outcomes
Johns Hopkins University
- Location
- Baltimore, MD
- Eligibility basics
- Ages 21–55
- RecruitingHealthy volunteersPhase 1
The Impact of Light Exposure on Cognitive Function in Classrooms
Michigan State University
- Location
- East Lansing, MI
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersEarly Phase 1
Imaging Mitochondrial Complex-I in Alcohol Use Disorder
Rajesh Narendran
- Location
- Pittsburgh, PA
- Eligibility basics
- Ages 18–55
- RecruitingHealthy volunteersPhase 1
Safety and Tolerability Trial of Psilocybin in Healthy Older Adults
University of Colorado, Denver
- Location
- San Francisco, CA + 5 other US sites
- Eligibility basics
- Ages 65–85
- RecruitingHealthy volunteersPhase 1/Phase 2
Assessing Pulmonary Changes in HSCT
Children's Hospital Medical Center, Cincinnati
- Location
- Cincinnati, OH
- Eligibility basics
- Ages 3+
- RecruitingHealthy volunteersPhase 1
Gamma Oscillations as a Prognostic Marker for Ketamine Therapy in Treatment Resistant Depression
Texas A&M University
- Location
- Houston, TX + 1 other US site
- Eligibility basics
- Ages 21–45
- RecruitingHealthy volunteersPhase 1
PRoMiSS: Psilocybin and the Role of Music in Set and Setting
Johns Hopkins University
- Location
- Baltimore, MD
- Eligibility basics
- Ages 21–75
- RecruitingHealthy volunteersPhase 1/Phase 2
Use of Hyperpolarized 129Xe MR Lung Imaging in Adults for Calibration
Children's Hospital Medical Center, Cincinnati
- Location
- Cincinnati, OH
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersEarly Phase 1
Single-tracer Multiparametric PET Imaging
University of California, Davis
- Location
- Sacramento, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1
Iadademstat + SBRT With Atezo in ES-SCLC
Yale University
- Location
- New Haven, CT
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersEarly Phase 1
Psilocybin Administration With 5-HT1a Blockade
Johns Hopkins University
- Location
- Baltimore, MD
- Eligibility basics
- Ages 21–60
- RecruitingHealthy volunteersEarly Phase 1
Imaging Mitochondrial Complex-I in Cocaine Use Disorder: a [F-18]BCPP-EF PET Study
Rajesh Narendran
- Location
- Pittsburgh, PA
- Eligibility basics
- Ages 18–45
- RecruitingHealthy volunteersPhase 1/Phase 2
Annatto-derived GG for Statin-associated Myopathy
Texas Tech University Health Sciences Center
- Location
- Lubbock, TX
- Eligibility basics
- Ages 40+
- RecruitingHealthy volunteersPhase 1
OMAR Opioid Use Disorder
Yale University
- Location
- New Haven, CT
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersEarly Phase 1
Impact of Early Aging and Menopause on the Vascular Responses to Hypoxia
University of Missouri-Columbia
- Location
- Columbia, MO
- Eligibility basics
- Ages 18–70 · Women only
- RecruitingHealthy volunteersPhase 1/Phase 2
Study of Cannabidiol and Neuroimaging on Stress
Icahn School of Medicine at Mount Sinai
- Location
- New York, NY
- Eligibility basics
- Ages 18–25
- RecruitingHealthy volunteersEarly Phase 1
Beta3-adrenergic Receptors and Cardiovascular Function in Aging Women
University of Missouri-Columbia
- Location
- Columbia, MO
- Eligibility basics
- Ages 18–70 · Women only
Who these studies look for
Phase 1 studies often have narrow eligibility: specific age and weight ranges, no recent participation in another study, no nicotine, and limits on medications. Some Phase 1 studies recruit patients rather than healthy volunteers, so check each listing.
Matching a page like this one never means you qualify. Each research team decides eligibility at screening.
Questions
Are Phase 1 trials riskier?
Every study carries risk. Phase 1 studies involve less human data about the product, which is why they are closely monitored. The informed consent document explains the known risks; read it carefully and ask questions before signing.
Why do some Phase 1 studies include overnight stays?
Staying in the unit lets staff dose on a precise schedule and collect samples around the clock. Where a record mentions an inpatient stay we flag it on the listing.