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
Understanding Allergies and Sensitizations in Healthy and Allergic Individuals
Stanford University
- Location
- Palo Alto, CA
- Eligibility basics
- Ages 0 mo–90
- RecruitingHealthy volunteers
Virtual Reality for ICU Delirium Prevention
Cedars-Sinai Medical Center
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Sleep Well Firefighters: An App-based Program to Improve Sleep, Cognition, and Behavioral Health in Firefighters
California Polytechnic State University-San Luis Obispo
- Location
- San Luis Obispo, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 4
Safety of RSV Preventive Monoclonal Antibody
Duke University
- Location
- Oakland, CA + 4 other US sites
- Eligibility basics
- Ages 1 mo–7 mo
- RecruitingHealthy volunteers
Treatment of Ocular Discomfort in Glaucoma Patients Using Multiple Topical Medications
University of California, Los Angeles
- Location
- Fountain Valley, CA
- Eligibility basics
- Any age listed
- RecruitingHealthy volunteers
Risk Assessment Evaluation for Identifying Participants at High Risk for Stomach Cancer
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Ages 40–80
- RecruitingHealthy volunteersPhase 2
Effect of Novel Exhalational Delivery System With Fluticasone (EDS-FLU) on Eustachian Tube Dysfunction (ETD)
Cedars-Sinai Medical Center
- Location
- Los Angeles, CA + 3 other US sites
- Eligibility basics
- Ages 18–80
- RecruitingHealthy volunteersPhase 2/Phase 3
Using Navigation to Improve Accuracy of Maxillary Balloon Sinusotomy
Cedars-Sinai Medical Center
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Transcutaneous Spinal Cord Stimulation for Chronic Low Back Pain
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 21–85
- RecruitingHealthy volunteersPhase 4
TReating Incontinence for Underlying Mental and Physical Health
University of California, San Francisco
- Location
- Palo Alto, CA + 1 other US site
- Eligibility basics
- Ages 60+ · Women only
- RecruitingHealthy volunteers
Students Rising Above: Offsetting the Health and Mental Health Costs of Resilience
University of California, Los Angeles
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 13+
- RecruitingHealthy volunteers
Fructose Intestinal Gluconeogenesis
Touro University, California
- Location
- Vallejo, CA
- Eligibility basics
- Ages 20–55
- RecruitingHealthy volunteers
Chronic Infections and Inflammation in ME/CFS: An Observational Study
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Enhancing Capacity in Churches to Implement PA Programs
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 18–65 · Women only
- RecruitingHealthy volunteers
Telephone-based Physical Activity Coaching or Self Monitored Physical Activity to Improve Physical Function in Older Adults Who Are Undergoing Surgery for Lung Cancer and Their Caregivers
City of Hope Medical Center
- Location
- Davis, CA + 15 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Testing & Refinement of CarePair: An Assessment and Referral Platform to Support Family Caregivers of Alzheimer's Disease and Related Dementias.
University of Southern California
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Evaluating AI-Generated Plain Language Summaries on Patient Comprehension of Ophthalmology Notes Among English-Speaking Patients
University of California, Los Angeles
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Brain Stimulation to the Hippocampus in Schizophrenia
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteers
Digital vs. Parent Modeled Toothbrushing
University of Southern California
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 3–6
- RecruitingHealthy volunteers
Parent-Mediated Intervention Targeting Insistence on Sameness for Autistic Children
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 6–11
- RecruitingHealthy volunteers
Multidisciplinary Low-Barrier and Mobile HIV Care to Improve Retention and Viral Suppression: Stakeholder-Engaged Design and Evaluation
University of California, San Francisco
- Location
- Oakland, CA + 4 other US sites
- Eligibility basics
- Ages 15+
- RecruitingHealthy volunteers
Health Properties of Pecan Nut Consumption
University of California, Davis
- Location
- Davis, CA
- Eligibility basics
- Ages 45–75
- RecruitingHealthy volunteers
An 8-Week Study Evaluating Gut and Digestive Health After Use of a Dietary Supplement System
SF Research Institute, Inc.
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–80
- RecruitingHealthy volunteers
Zinc and Iron Absorption From Common Beans in Young Adult Women
University of California, Davis
- Location
- Davis, CA
- Eligibility basics
- Ages 19–24 · Women only