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
PET Imaging Study of 64Cu-GRIP B for Patients Receiving CD19-directed CAR-T Therapy
Michael Randall
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersEarly Phase 1
Precision Dosing of Metformin in Youth With T2D
University of California, San Francisco
- Location
- Oakland, CA + 1 other US site
- Eligibility basics
- Ages 10–21
- RecruitingHealthy volunteersPhase 1
THC and CBD: A Controlled Human Study Probing a Harm Reduction Strategy
University of California, Los Angeles
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 21–55
- RecruitingHealthy volunteersPhase 1
Delayed Immunological Tolerance in Patients With Well-functioning Pre-existing HLA-matched Kidney Transplants
University of California, Los Angeles
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1
Investigating the Persisting Effects of a Single Dose of Psilocybin on Structural Plasticity in Healthy Older Adults
University of California, Berkeley
- Location
- Berkeley, CA
- Eligibility basics
- Ages 60–85
- RecruitingHealthy volunteersEarly Phase 1
Vocal Emotion Communication With Cochlear Implants
Father Flanagan's Boys' Home
- Location
- Los Angeles, CA + 2 other US sites
- Eligibility basics
- Ages 6–80
- RecruitingHealthy volunteersPhase 1
1726-nm Laser for Acne Inversa (Hidradenitis Suppurativa)
Wynn Medical Center
- Location
- Rosemead, CA
- Eligibility basics
- Ages 18–60
- RecruitingHealthy volunteersPhase 1
Azithromycin Before Induction
Arrowhead Regional Medical Center
- Location
- Colton, CA
- Eligibility basics
- Ages 18–45 · Women only
- RecruitingHealthy volunteersOvernight stay mentioned
Effects of Using a Storybook, to Explain Leukemia to Children Versus the Standard Child Life Intervention, on Parental Stress.
Children's Hospital Los Angeles
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 3+
- RecruitingHealthy volunteersPhase 1
PET Imaging of Radiolabeled Anti-HIV-1 Envelope Monoclonal Antibody (VRC01)
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 1/Phase 2
First-in-Human Evaluation of an Astrocytic Glutamate Transporter (EAAT2) PET Tracer in Dementia
David Wilson
- Location
- San Francisco, CA
- Eligibility basics
- Ages 40–75
- RecruitingHealthy volunteersPhase 1
Imaging Synapses With [11C] UCB-J in the Human Brain
Davidzon, Guido, M.D.
- Location
- Palo Alto, CA + 1 other US site
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 1
CogT pSOPT Intervention Study
Stanford University
- Location
- Palo Alto, CA
- Eligibility basics
- Ages 60+
- RecruitingHealthy volunteersPhase 1
Treating Primary Sclerosing Cholangitis and Biliary Atresia With Vancomycin
Sacramento Pediatric Gastroenterology
- Location
- Sacramento, CA
- Eligibility basics
- Ages 0 mo–40
- RecruitingHealthy volunteers
Prospective Multi-Center Trial for FemBloc Permanent Birth Control
Femasys Inc.
- Location
- Palo Alto, CA + 11 other US sites
- Eligibility basics
- Ages 21–50 · Women only
- RecruitingHealthy volunteersPhase 3
A Study to Learn About How a New Pneumococcal Vaccine Works in Infants.
Pfizer
- Location
- Anaheim, CA + 101 other US sites
- Eligibility basics
- Ages 1 mo–7 mo
- RecruitingHealthy volunteersPhase 3
A Study of Aleniglipron in Adults With Obesity or Overweight and Type 2 Diabetes Mellitus (ACCOMPLISH-2)
Gasherbrum Bio, Inc., a wholly owned subsidiary of Structure Therapeutics
- Location
- Fountain Valley, CA + 55 other US sites
- Eligibility basics
- Ages 18–79
- RecruitingHealthy volunteers
IgG Binding Protein LT in Support of a Healthy Gut on the Go
Bactolife A/S
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18–70
- RecruitingHealthy volunteers
Galleri® in the Medicare Population.
GRAIL, Inc.
- Location
- Auburn, CA + 70 other US sites
- Eligibility basics
- Ages 50+
- RecruitingHealthy volunteersPhase 3
A Study to Evaluate the Efficacy and Safety of CBL-514 Injection for Reducing Subcutaneous Fat
Caliway Biopharmaceuticals Co., Ltd.
- Location
- Encinitas, CA + 5 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
GUT-FEELINGS: Using Citizen Science for Large-Scale Prebiotic Clinical Trials for Mental Wellness in Adults
Holobiome, Inc.
- Location
- Del Mar, CA
- Eligibility basics
- Ages 21–80
- RecruitingHealthy volunteers
Scaling Effective Behavioral Interventions With MPC Avatar-Based Virtual Training
dfusion Inc
- Location
- Scotts Valley, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Safety and Tolerability Evaluation of IgG Binding Protein LT
Bactolife A/S
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18–70
- RecruitingHealthy volunteersPhase 4
Study to Assess Safety and Tolerability of KarXT With Administration of Antiemetics in Healthy Volunteers
Karuna Therapeutics, Inc., a Bristol Myers Squibb company
- Location
- Los Alamitos, CA + 3 other US sites
- Eligibility basics
- Ages 18–65