Healthy volunteers · California
Studies for healthy volunteers in California
701 studies have at least one recruiting site in California. These studies say in their official record that they accept healthy volunteers. Many are Phase 1 studies that test how a new medicine is absorbed and tolerated; others recruit healthy people as a comparison group alongside patients.
701 recruiting studiesSource: ClinicalTrials.gov, refreshed October 26, 2026How we list studies
More recruiting studies (pay not posted)
- 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
- RecruitingHealthy volunteersPhase 4
Study of a Recombinant Spike COVID-19 Vaccine With Matrix-M in Older Adults and People at Increased Risk of Severe COVID-19
Sanofi
- Location
- Fair Oaks, CA + 19 other US sites
- Eligibility basics
- Ages 12+
- RecruitingHealthy volunteersPhase 3
A Phase 3 Study of Revaccination in Subsequent Pregnancies With Bivalent RSV Vaccine and Duration of Protection of a Single Dose
Pfizer
- Location
- Los Angeles, CA + 76 other US sites
- Eligibility basics
- Ages 0 mo+
- RecruitingHealthy volunteersPhase 3
A Study to Assess the Safety, Tolerability, and Immunogenicity of 3 Lots of a Multivalent Pneumococcal Conjugate Vaccine Administered to Adults
Pfizer
- Location
- Lake Forest, CA + 36 other US sites
- Eligibility basics
- Ages 18–49
- RecruitingHealthy volunteersPhase 3
A Study to Learn About a Clostridioides Difficile Vaccine in People 65 Years of Age and Older
Pfizer
- Location
- Daly City, CA + 138 other US sites
- Eligibility basics
- Ages 65+
Who these studies look for
“Healthy” is decided at screening, not by you. Sites usually check vital signs, blood and urine tests, an ECG, your medications and sometimes your BMI or smoking status. A study can still turn you away for reasons that have nothing to do with being unwell, such as timing or a full roster.
Matching a page like this one never means you qualify. Each research team decides eligibility at screening.
Questions
Do healthy volunteer studies pay?
Many do, because volunteers give up time and follow strict schedules, but amounts are set by each study and are usually only confirmed by the research site. When a record states an amount we show the exact wording; otherwise we say compensation is not disclosed.
What happens at a screening visit?
Expect consent paperwork first, then a health questionnaire, vital signs, blood and urine samples and often an ECG. You can ask questions and withdraw at any time, before or after you sign.