Location · California
Clinical trials recruiting in California
1900 recruiting studies have at least one site in California; 700 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.
1,900 recruiting studiesSource: ClinicalTrials.gov, refreshed October 27, 2026How we list studies
More recruiting studies (pay not posted)
- RecruitingHealthy volunteers
Combatting HIV Or Other STIs Early (CHOOSE)
Westat
- Location
- San Francisco, CA + 5 other US sites
- Eligibility basics
- Ages 13–24 · Men only
- RecruitingHealthy volunteers
Voices Illuminating Solutions for Outdoor Workers' Needs and Safety
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Tear Fluid for the Detection of Tumor-associated Extracellular Vesicles in Glioblastoma Patients
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
ARTFL LEFFTDS Longitudinal Frontotemporal Lobar Degeneration (ALLFTD)
Mayo Clinic
- Location
- Los Angeles, CA + 22 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Nicotinamide Mononucleotide Supplementation for Exercise Tolerance Improvement in Healthy Older Adults
Scott Silveira
- Location
- Beverly Hills, CA
- Eligibility basics
- Ages 60–80
- RecruitingHealthy volunteers
Surgical Thromboprophylaxis Practices in Oncology Patients Within the NCORP Network, STOP-VTE Study
Wake Forest University Health Sciences
- Location
- Oakland, CA + 101 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 4
Prescription of Letrozole for Uterine Myoma
University of California, San Francisco
- Location
- Los Angeles, CA + 4 other US sites
- Eligibility basics
- Ages 21–53 · Women only
- RecruitingHealthy volunteers
The Vanguard Study: Testing a New Way to Screen for Cancer
National Cancer Institute (NCI)
- Location
- Pleasanton, CA + 44 other US sites
- Eligibility basics
- Ages 45–75
- RecruitingHealthy volunteers
Efficacy of mHealth Applications in Weight Management in a Population Affected by Overweight or Obesity
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 18–64
- RecruitingHealthy volunteers
Efficacy of mHealth Apps for Health in a Low-income, Type II Diabetic, Hispanic Population
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 18–64
- RecruitingHealthy volunteers
Collecting Blood Samples From Patients With and Without Cancer to Evaluate Tests for Early Cancer Detection
Alliance for Clinical Trials in Oncology
- Location
- Arroyo Grande, CA + 612 other US sites
- Eligibility basics
- Ages 40–75
- RecruitingHealthy volunteers
Exercise in Child Health
University of California, Irvine
- Location
- Irvine, CA
- Eligibility basics
- Ages 10–17
- RecruitingHealthy volunteers
Efficacy of Using Mobile Health Applications for Health
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 18–64
- RecruitingHealthy volunteers
Smoking Cessation CM for Veterans With or at Risk for Cancer
VA Office of Research and Development
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Promoting Physical Activity and Fitness Among Underserved Latino Families Living in U.S.-Mexico Border Regions
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 6+
- RecruitingHealthy volunteers
Gauging Outcomes of Total Milk Ingestion on Lipid and gControl
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
A Multi-level Mother-daughter Physical Activity Intervention for Pre- Adolescent Latinas
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 8–65 · Women only
- RecruitingHealthy volunteers
Testing an Enhanced Digital Delivery Model for Inherited Cancer Genetic Testing in Young Adults With Cancer
Alliance for Clinical Trials in Oncology
- Location
- Arroyo Grande, CA + 319 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Family Communications After Genetic Testing
Alliance for Clinical Trials in Oncology
- Location
- Arroyo Grande, CA + 347 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Studying the PAGODA Algorithm for Chemotherapy Dose Changes to Prevent Unplanned Treatment Delays
Alliance for Clinical Trials in Oncology
- Location
- Arroyo Grande, CA + 350 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Cognitive Neurocomputational Task Reliability & Clinical Applications Consortium (CNTRACS): Study 1
Washington University School of Medicine
- Location
- Irvine, CA + 4 other US sites
- Eligibility basics
- Ages 18–59
- RecruitingHealthy volunteers
Buprenorphine Implementation at Syringe Service Programs to Reduce Overdoses
Montefiore Medical Center
- Location
- Los Angeles, CA + 7 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Improving Productive Community Integration in Homeless-experienced Veterans
VA Office of Research and Development
- Location
- West Los Angeles, CA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 4
Bupivacaine With Epinephrine Over Diaphragm in Laparoscopy
Cedars-Sinai Medical Center
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18+ · Women only