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
Evaluation of Geriatric Assessment and Management for Older Adults With Non-small Cell Lung Cancer Receiving Chemotherapy Radiation Therapy
City of Hope Medical Center
- Location
- Duarte, CA + 1 other US site
- Eligibility basics
- Ages 60+
- RecruitingHealthy volunteers
Brain Health in Breast Cancer Survivors
Jonsson Comprehensive Cancer Center
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 35–65 · Women only
- RecruitingHealthy volunteers
Early Onset Colorectal Cancer Detection
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Ages 18–50
- RecruitingHealthy volunteers
Early Detection of Advanced Adenomas and Colorectal Cancer
City of Hope Medical Center
- Location
- Monrovia, CA + 1 other US site
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
A Noninvasive and Screening miRNA Signature for Gastrointestinal Cancer
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Liquid Biopsy for Early Detection of Colorectal Cancer Using Circular RNA
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Integrated Cf-miRNA and Exosomal miRNA Signature for Early Detection of Esophageal Squamous Cell Carcinoma
City of Hope Medical Center
- Location
- Monrovia, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
PEP/PrEP Via Pharmacist-Prescribing Implementation (PEPPI)
EMPOWERX INC
- Location
- Del Mar, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Immunomodulatory Effects of Fasting in Healthy Adults
University of California, Davis
- Location
- Sacramento, CA
- Eligibility basics
- Ages 20–40
- RecruitingHealthy volunteers
Gender Disparities in Voice Outcomes After Tracheoesophageal Puncture in Total Laryngectomy Patients (UC Davis)
University of California, Davis
- Location
- La Jolla, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Magnetic Resonance Imaging of Breast Cancer
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 21+ · Women only
- RecruitingHealthy volunteers
Project for Multi-Omics-Based Early Detection of Hepatocellular Carcinoma (PROMETHEA Study)
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Blossom® Smart Expander Device for Tissue Expander/Implant-Based Breast Reconstruction
Stanford University
- Location
- Palo Alto, CA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteers
Molecular Genetics Studies of Cancer Patients and Their Relatives
City of Hope Medical Center
- Location
- Concord, CA + 33 other US sites
- Eligibility basics
- Any age listed
- RecruitingHealthy volunteers
The Actuate-CBC Study
University of Pennsylvania
- Location
- Orange, CA + 2 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Developing a Nutritional Supplement to Increase Collagen Synthesis in People
University of California, Davis
- Location
- Davis, CA
- Eligibility basics
- Ages 18–30
- RecruitingHealthy volunteers
Practice Facilitation as a Strategy to Improve Alcohol Treatment Adoption and Implementation in HIV Care
Johns Hopkins University
- Location
- San Diego, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Early Introduction and Sustained Ingestion (EISI) Using Two Educational Opportunities in Infants
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 4 mo–11 mo
- RecruitingHealthy volunteers
Modified Pivotal Response Treatment for Insistence on Sameness in Autistic Youth
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 4–17
- RecruitingHealthy volunteers
Better Breaks: Strength Breaks vs Walk Breaks for Sedentary Behavior Breaks
Stanford University
- Location
- Palo Alto, CA
- Eligibility basics
- Ages 30+
- RecruitingHealthy volunteers
Teen Helpline Motivational Interviewing Study
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 13+
- RecruitingHealthy volunteers
Circulating Biomarkers in the Development of Type 1 Diabetes
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Any age listed
- RecruitingHealthy volunteers
Investigating the Feasibility and Acceptability of an Innovative Interdisciplinary Supportive Care Program: Couples Coping Together Against Cancer
City of Hope Medical Center
- Location
- Duarte, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Sleep TMS for Depression
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 18–65