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 3
A Study to Evaluate the Immune Response and Safety of a Vaccine Against Influenza in Adults 18-64 Years of Age
GlaxoSmithKline
- Location
- San Diego, CA + 11 other US sites
- Eligibility basics
- Ages 18–64
- RecruitingHealthy volunteers
Contraceptive Efficacy Study of Ovaprene
Daré Bioscience, Inc.
- Location
- Newhall, CA + 3 other US sites
- Eligibility basics
- Ages 18–40 · Women only
- RecruitingHealthy volunteersPhase 3
Fertilo In Vitro Research Study and Trial
Gameto, Inc.
- Location
- Clovis, CA + 15 other US sites
- Eligibility basics
- Ages 18–35 · Women only
- RecruitingHealthy volunteers
BoxX-NoAF Clinical Trial
AtriCure, Inc.
- Location
- San Diego, CA + 30 other US sites
- Eligibility basics
- Ages 65+
- RecruitingHealthy volunteers
ProACT Post-Approval Study
Uromedica
- Location
- Los Angeles, CA + 13 other US sites
- Eligibility basics
- Ages 50+ · Men only
- RecruitingHealthy volunteers
Impact of Two Iron Formulations on Iron Biomarkers and Quality of Life
Qualia Life Sciences
- Location
- Carlsbad, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteersPhase 3
Lot-to-lot Consistency Study of a 21-valent Pneumococcal Conjugate Vaccine in Healthy Infants From 2 Months of Age
Sanofi
- Location
- Huntington Park, CA + 13 other US sites
- Eligibility basics
- Ages 1 mo–2 mo
- RecruitingHealthy volunteers
Efficacy of Qualia Testosterone+ on Testosterone Levels in Adult Males
Qualia Life Sciences
- Location
- Carlsbad, CA
- Eligibility basics
- Ages 28–65 · Men only
- RecruitingHealthy volunteers
The Impact of Qualia Vitamin C+ on Individuals With Suboptimal and Adequate Vitamin C Levels
Qualia Life Sciences
- Location
- Carlsbad, CA
- Eligibility basics
- Ages 25–75
- RecruitingHealthy volunteers
Positron Emission Tomography/Computed Tomography (PECT/CT) Double-Scanning Study
GE Healthcare
- Location
- Stanford, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
A Study to Assess Deucravacitinib Safety in Pregnancy
Bristol-Myers Squibb
- Location
- La Jolla, CA
- Eligibility basics
- Any age listed · Women only
- RecruitingHealthy volunteers
Observational Study of Decentralized Urine Optical Interaction Patterns Associated With Environmental Microplastic and Nanoplastic Exposure
Ecotera Health LLC
- Location
- San Francisco, CA + 50 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
A Randomized Comparison of Stage-Based Care Versus Risk Factor-Based Care for Prevention of Cardiovascular Events
Cleerly, Inc.
- Location
- Beverly Hills, CA + 121 other US sites
- Eligibility basics
- Ages 55+
- RecruitingHealthy volunteersPhase 3
BEATRIX: A Study to Learn About a Group B Streptococcus Vaccine in Healthy Pregnant Women and Their Babies
Pfizer
- Location
- Lancaster, CA + 111 other US sites
- Eligibility basics
- Ages 0 mo–49
- RecruitingHealthy volunteers
Multi-strain Probiotic Supplement for Digestive Comfort and Well-being in Healthy Women
Daily Nouri
- Location
- San Francisco, CA
- Eligibility basics
- Ages 25–45 · Women only
- RecruitingHealthy volunteersPhase 3
A Study on the Efficacy of a Vaccine Against Influenza in Adults ≥65 Years of Age
GlaxoSmithKline
- Location
- Dublin, CA + 130 other US sites
- Eligibility basics
- Ages 65+
- RecruitingHealthy volunteers
An Open-Label, Two-Arm Pilot Study of the Tolerability, Consumer Acceptability, and Exploratory Well-Being Outcomes of a Multi-Ingredient Protein Formula in Two Flavors in Healthy Adults
Qualia Life Sciences
- Location
- Carlsbad, CA
- Eligibility basics
- Ages 21–65
- RecruitingHealthy volunteers
This Study Evaluates the ALPCO Syphilis-T and Syphilis-NT CLIA Kits for Detecting Syphilis Antibodies in Serum and Plasma. Samples From At-risk, HIV-positive, Pregnant, and Healthy Individuals Will Assess Assay…
American Laboratory Products Company
- Location
- Lancaster, CA + 5 other US sites
- Eligibility basics
- Ages 13+
- RecruitingHealthy volunteers
The Happiest Baby, Inc. SNOO Postmarket Surveillance Study
Happiest Baby, Inc.
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Observational, Non-Interventional Study Supporting Validation of eVO2peak Using Results in Patients Receiving Standard of Care Cardiopulmonary Exercise Tests (CPET)
Prolaio
- Location
- Palo Alto, CA + 10 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Effects of P24 on Postprandial Aminoacidemia
Amplifye
- Location
- Davis, CA
- Eligibility basics
- Ages 45–75
- RecruitingHealthy volunteers
A Study to Test the AdaptDx Pro Agreement in Rod Intercept Time With the AdaptDx in Healthy Subjects With Normal Vision (FlashBack)
AdaptDx, Inc.
- Location
- San Diego, CA
- Eligibility basics
- Ages 22–49
- RecruitingHealthy volunteersPhase 3
Study to Learn About Safety, Tolerability, and Immune Response of a Catch-up Pneumococcal Vaccine in Children and Adolescents
Pfizer
- Location
- Fair Oaks, CA + 49 other US sites
- Eligibility basics
- Ages 1–17
- RecruitingHealthy volunteers
(CIRRUS-2023-1) CLINICAL CLIN Assessment of PathFinder 1.0 on the CIRRUS 6000 and the CIRRUS 5000
Carl Zeiss Meditec-Dublin CoCe
- Location
- Mountain View, CA + 4 other US sites
- Eligibility basics
- Ages 18+
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.