Location · California
Clinical trials recruiting in California
1898 recruiting studies have at least one site in California; 701 accept healthy volunteers. Studies that need a specific condition are included too, so check each listing.
Want the research companies that run paid Phase 1 studies for healthy volunteers? Paid clinical trial companies in California.
1,898 recruiting studiesSource: ClinicalTrials.gov, refreshed October 26, 2026How we list studies
More recruiting studies (pay not posted)
- RecruitingHealthy volunteersPhase 1
A Study to Evaluate the Effect of Food on the Bioavailability of AJ201, and Safety, Tolerability, and Pharmacokinetics of AJ201 in Japanese and White Healthy Male Participants
AnnJi Pharmaceutical Co., Ltd.
- Location
- Los Alamitos, CA
- Eligibility basics
- Ages 18–55 · Men only
- RecruitingHealthy volunteersPhase 1/Phase 2
A Trial to Learn if ALN-PNP is Safe and Well Tolerated in Healthy Adults and Adult Participants With Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)
Regeneron Pharmaceuticals
- Location
- Los Angeles, CA + 4 other US sites
- Eligibility basics
- Ages 18–75
- RecruitingHealthy volunteersPhase 1
A First-in-Human Single and Multiple Ascending Dose Study of MT-251
Mirador Therapeutics, Inc.
- Location
- San Diego, CA
- Eligibility basics
- Ages 19–55
- RecruitingHealthy volunteersPhase 1
Evaluate the Pharmacokinetics, Safety, and Tolerability of NSHO-101 in Healthy Participants
Ensho Therapeutics, Inc.
- Location
- Anaheim, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersEarly Phase 1
Single and Multiple Ascending Doses of NTX-253 in Healthy Participants and Participants With Stable Schizophrenia
Neurosterix
- Location
- Los Alamitos, CA
- Eligibility basics
- Ages 18–55
- RecruitingHealthy volunteersPhase 1
A Study to Evaluate the Safety, Tolerability, and Drug Levels of BMS-986521 in Healthy Participants.
Bristol-Myers Squibb
- Location
- Anaheim, CA
- Eligibility basics
- Ages 18–80
- RecruitingHealthy volunteersPhase 1
A First-in-Human Single and Multiple Ascending Dose Study of MT-201
Mirador Therapeutics, Inc.
- Location
- San Diego, CA
- Eligibility basics
- Ages 19–55
- RecruitingHealthy volunteersPhase 1/Phase 2
Study of VGA039 in Healthy Volunteers and Patients With Von Willebrand Disease (VIVID)
Vega Therapeutics, Inc
- Location
- Los Angeles, CA + 9 other US sites
- Eligibility basics
- Ages 12–60
- RecruitingHealthy volunteersPhase 1/Phase 2
Safety, PK and Biodistribution of 18F-OP-801 in Patients With ALS, AD, MS, PD and Healthy Volunteers
Ashvattha Therapeutics, Inc.
- Location
- San Francisco, CA + 2 other US sites
- Eligibility basics
- Ages 18–80
- RecruitingHealthy volunteersPhase 1/Phase 2
Spermatogonial Differentiation Via Testicular Organoid
CellARTs Inc.
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–60 · Men only
- RecruitingHealthy volunteersPhase 1
A Phase 1 Study to Evaluate Safety, Tolerability and Pharmacokinetics of TIX100 in Healthy Subjects
TIXiMED, Inc.
- Location
- Chula Vista, CA
- Eligibility basics
- Ages 18–70
- RecruitingHealthy volunteersPhase 1/Phase 2
Mesenchymal Stem Cells for the Treatment of Various Chronic and Acute Conditions
Thomas Advanced Medical LLC
- Location
- Culver City, CA
- Eligibility basics
- Ages 18+
- RecruitingPhase 1Overnight stay mentioned
A Study of GNTI-122 in Adults Recently Diagnosed With T1D
GentiBio, Inc
- Location
- Duarte, CA + 8 other US sites
- Eligibility basics
- Ages 18–55
- RecruitingPhase 1/Phase 2Overnight stay mentioned
Study is to Assess the Safety and Tolerability of VTx-002 in Participants With ALS
Vector Y Therapeutics
- Location
- San Diego, CA + 3 other US sites
- Eligibility basics
- Ages 18+
- RecruitingPhase 1Overnight stay mentioned
A Study of LTX-001 In Adult Participants With Acute Exacerbation of Schizophrenia
Leal Therapeutics, Inc
- Location
- Los Alamitos, CA + 9 other US sites
- Eligibility basics
- Ages 18–55
- RecruitingPhase 1Overnight stay mentioned
Determining Efficacy and Safety of BXCL501 in Agitation Associated With Pediatric Schizophrenia and Bipolar Disorder
BioXcel Therapeutics Inc
- Location
- Anaheim, CA + 3 other US sites
- Eligibility basics
- Ages 10–17
- RecruitingHealthy volunteersPhase 1
A Vaccine (CMV-MVA Triplex Vaccine) for the Enhancement of CMV-Specific Immunity and the Prevention of CMV Viremia in Patients Undergoing Haploidentical Hematopoietic Stem Cell Transplant
City of Hope Medical Center
- Location
- Duarte, CA + 2 other US sites
- Eligibility basics
- Ages 18–75
- RecruitingHealthy volunteersPhase 1
Safety Study of MucoCept-CVN
Craig Cohen, MD, MPH
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–45 · Women only
- 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 volunteersEarly Phase 1
Entire-body PET Scans for Multiple Sclerosis
Brain Health Alliance
- Location
- Ladera Ranch, CA
- Eligibility basics
- Ages 25–55
- RecruitingHealthy volunteersPhase 1
Inflammatory Challenge and Fear
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–65
- 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
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 volunteersEarly Phase 1
Single-tracer Multiparametric PET Imaging
University of California, Davis
- Location
- Sacramento, CA
- Eligibility basics
- Ages 18+