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 volunteersEarly Phase 1
Contribution of UGT2B17 to the Pharmacokinetics of Diclofenac
Washington State University
- Location
- Spokane, WA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 1
Quadrivalent Influenza HA Stem Vaccine VRC-FLUMOS0122-00-VP (SteMos1) With and Without ALFQ Adjuvant in Healthy Adults
National Institute of Allergy and Infectious Diseases (NIAID)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 18–50
- RecruitingHealthy volunteersPhase 1
Impact of Early ADL Education on Outcomes Post DRF ORIF
George Washington University
- Location
- Washington, VA
- Eligibility basics
- Ages 18–110
- RecruitingHealthy volunteersPhase 1/Phase 2
Suvorexant for Alcohol Use Disorder (AUD): Neural Mechanisms
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 18–75
- RecruitingHealthy volunteersPhase 1
Army-SPRING Army-Suicide Prevention Research
University of Pennsylvania
- Location
- Philadelphia, PA
- Eligibility basics
- Any age listed
- RecruitingHealthy volunteersPhase 1
Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of Fx-5A in Healthy Volunteers
National Heart, Lung, and Blood Institute (NHLBI)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 18–99
- RecruitingHealthy volunteersPhase 1/Phase 2
Phase I/II Study to Reduce Post-transplantation Cyclophosphamide Dosing for Older or Unfit Patients Undergoing Bone Marrow Transplantation for Hematologic Malignancies
National Cancer Institute (NCI)
- Location
- Bethesda, MD + 1 other US site
- Eligibility basics
- Ages 12–85
- RecruitingHealthy volunteersPhase 1/Phase 2
Donor Lymphocyte Infusion After Allogeneic Hematopoietic Cell Transplantation for High-Risk Hematologic Malignancies
National Cancer Institute (NCI)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 12–120
- RecruitingHealthy volunteersPhase 1/Phase 2
The Lowest Effective Dose of Post-Transplantation Cyclophosphamide in Combination With Sirolimus and Mycophenolate Mofetil as Graft-Versus-Host Disease Prophylaxis After Reduced Intensity Conditioning and Peripheral…
National Cancer Institute (NCI)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 12–120
- RecruitingHealthy volunteersPhase 1/Phase 2
Trial of Allogeneic Reduced-Intensity, HLA-Haploidentical Allogeneic Hematopoietic Cell Bone Marrow Transplantation Followed by Graft-versus-Host-Disease (GVHD) Prophylaxis With Cyclophosphamide, Bortezomib and…
National Cancer Institute (NCI)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 12–120
- RecruitingHealthy volunteersPhase 1/Phase 2
Topical Netarsudil for the Prevention of Proliferative Vitreoretinopathy in Patients With Retinal Detachment
Massachusetts Eye and Ear Infirmary
- Location
- Boston, MA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1
pH1N1 Blinded Challenge Study
National Institute of Allergy and Infectious Diseases (NIAID)
- Location
- Baltimore, MD + 1 other US site
- Eligibility basics
- Ages 18–55
- RecruitingHealthy volunteersPhase 1
Safety Study of MucoCept-CVN
Craig Cohen, MD, MPH
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–45 · Women only
- RecruitingHealthy volunteersEarly Phase 1
Sleep, Dreaming, and Virtual Reality for Mental Health
Northwestern University
- Location
- Evanston, IL + 1 other US site
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1
Writing About Experiences and Health in Older Adults II
University of California, Los Angeles
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 65+
- RecruitingHealthy volunteersPhase 1
Danvatirsen Monotherapy Followed by Combination With Venetoclax in Relapsed/Refractory MDS & AML
Montefiore Medical Center
- Location
- The Bronx, NY + 1 other US site
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1/Phase 2
SV2A & TSPO PET Imaging Measures to Reveal Mechanisms of HIV Neuropathogenesis During Antiretroviral Therapy
Yale University
- Location
- New Haven, CT
- Eligibility basics
- Ages 18–80
- RecruitingHealthy volunteersPhase 1
Use of Pulsatile Intravenous FSH to Mitigate Reprometabolic Syndrome
University of Colorado, Denver
- Location
- Aurora, CO
- Eligibility basics
- Ages 19–37 · Women only
- RecruitingHealthy volunteersPhase 1
Membrane Potential Mapping with18F-TPP
Yale University
- Location
- New Haven, CT
- Eligibility basics
- Ages 21–80
- RecruitingHealthy volunteersPhase 1
Acute Effects of THC in Older Adult
Yale University
- Location
- West Haven, CT
- Eligibility basics
- Ages 21+
- RecruitingHealthy volunteersPhase 1/Phase 2
Safety and Immunogenicity of Recombinant Varicella Zoster Virus Vaccine in People With HIV Who Have a CD4 Count Less Than 300 or Greater Than or Equal to 300 and a Healthy Control Population
National Institute of Allergy and Infectious Diseases (NIAID)
- Location
- Bethesda, MD
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1
Pilot Study on the Effects of Psilocybin on Belief Updating and Insight Formation
Brown University
- Location
- Providence, RI
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1
Investigating the Utility of Demyelination Tracer [18F]3F4AP in Controls and Multiple Sclerosis Subjects
Massachusetts General Hospital
- Location
- Boston, MA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 1
Validation of Nanosensor Oxygen Measurement
Children's Hospital of Philadelphia
- Location
- Philadelphia, PA
- Eligibility basics
- Ages 18–65
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.