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 volunteers
Lung Macrophage Populations and Functions in Chronic Obstructive Pulmonary Disease (COPD)-Susceptible Smokers
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 40–75
- RecruitingHealthy volunteersPhase 2
Investigating the Use of Intravenous Tranexamic Acid in Gender Affirming Mastectomy
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+ · Women only
- RecruitingHealthy volunteersPhase 4
Immune Spatial Features of Guselkumab Cutaneous Response
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
The Society for Obstetric Anesthesia and Perinatology Research Network General Anesthesia Registry
Yale University
- Location
- San Francisco, CA + 32 other US sites
- Eligibility basics
- Ages 15–55 · Women only
- RecruitingHealthy volunteers
Analysis of Lumbar Spine Stenosis Specimens for Identification of Transthyretin Cardiac Amyloidosis
Columbia University
- Location
- Beverly Hills, CA + 4 other US sites
- Eligibility basics
- Ages 50+
- RecruitingHealthy volunteersPhase 2
Investigating the Interaction of Psilocybin and Context of Its Administration in Healthy Volunteers
Robin Carhart-Harris, PhD, MA
- Location
- San Francisco, CA
- Eligibility basics
- Ages 21–70
- RecruitingHealthy volunteers
Healthy Family Project: Tobacco Use and Smoke Exposure in Asian American Communities
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
SPIROMICS Study of Early COPD Progression (SOURCE)
University of Massachusetts, Worcester
- Location
- Los Angeles, CA + 13 other US sites
- Eligibility basics
- Ages 30–55
- RecruitingHealthy volunteers
Multisite Implementation of COMPRENDO
University of California, San Diego
- Location
- San Diego, CA + 3 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 2
Glutide for Ending Methamphetamine
San Francisco Department of Public Health
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 4
Vancomycin in TKAs
University of California, San Diego
- Location
- San Diego, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Effect of Gerofit Exercise on Cognition in Older Veterans
VA Office of Research and Development
- Location
- West Los Angeles, CA + 1 other US site
- Eligibility basics
- Ages 65+
- RecruitingHealthy volunteers
Breast Cancer Screening Adherence for Women at Moderate Risk for Breast Cancer
University of Southern California
- Location
- Los Angeles, CA + 1 other US site
- Eligibility basics
- Ages 30–75 · Women only
- RecruitingHealthy volunteers
Effectiveness of Cognitive Training in Older and Younger Adults
University of Wisconsin, Madison
- Location
- Riverside, CA + 2 other US sites
- Eligibility basics
- Ages 18–85
- RecruitingHealthy volunteers
The INSPIRE -Faith Study: Intervention Strategies for Preserving Intellectual Resilience and Engagement
Healthy Minds Initiative
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 55–85
- RecruitingHealthy volunteers
Comparing Two School-Based Sleep Health Interventions To Promote Sleep Quality in Youth
Children's Hospital Los Angeles
- Location
- Los Angeles, CA + 1 other US site
- Eligibility basics
- Ages 12–18
- RecruitingHealthy volunteers
Online Pivotal Response Treatment Training in Autism Spectrum Disorder
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 2–5
- RecruitingHealthy volunteers
Tumor Genomics, Individual Risk Factors, and External Drivers of Health on Health Outcomes for Patients With Meningioma
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Milk-Tot Study: Impact of Whole Versus Low-fat Milk on Child Health
University of California, Davis
- Location
- Oakland, CA
- Eligibility basics
- Ages 1–4
- RecruitingHealthy volunteers
Blood Flow Restriction Training as a Targeted Intervention for Rowers With Back Pain.
Loma Linda University
- Location
- Loma Linda, CA
- Eligibility basics
- Ages 13–20
- RecruitingHealthy volunteers
Prostate Cancer Screening for People at Genetic Risk for Aggressive Disease, PATROL Study
University of Washington
- Location
- Duarte, CA + 6 other US sites
- Eligibility basics
- Ages 40+ · Men only
- RecruitingHealthy volunteers
Detection of EEG-Based Biomarkers of Chronic Low Back Pain
Stanford University
- Location
- Palo Alto, CA
- Eligibility basics
- Ages 18–80
- RecruitingHealthy volunteers
Variations in Ketone Metabolism
Ohio State University
- Location
- Novato, CA + 1 other US site
- Eligibility basics
- Ages 20–70
- RecruitingHealthy volunteers
Cardiac-Control Affecting Learning Through Mindfulness (CALM)
University of Southern California
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 50–70