California Paid Clinical Trials

A listing of 5602 clinical trials in California actively recruiting volunteers for paid trials and research studies in various therapeutic areas.

Home

All Clinical Trials

California

Show Filters

Match to Clinical Trials

Access to cutting-edge treatments

Latest clinical trials

Find trials in your area

Start Matching

Filter by Location

Filter by Age

California is currently home to 5602 active clinical trials, seeking participants for engagement in research studies. These trials take place at a variety of cities in the state, including Los Angeles, San Francisco, San Diego and Sacramento. Whether you're a healthy volunteer interested in paid medical research or someone seeking trials related to a specific condition, the state offers a diverse array of opportunities in your vicinity.

Featured Trial

Healthy Participants Needed (Colonoscopy + Cancer Screening)

Recruiting

Earn $325 - $475 in electronic payment card compensation for your time and effort by participating in a clinical study to develop a blood test that may one day help screen for colon cancer. Take a quick quiz to see if you qualify.

Conditions:

Healthy

Healthy Volunteers

Healthy Subjects

Healthy Volunteer

Healthy Participants

Learn More

Featured Trial

Paid Clinical Studies Nationwide

Recruiting

Nationwide clinical trials offered in your area. Some trials offering up to several thousand dollars in compensation for participation.

Conditions:

Healthy

Healthy Volunteer Study

Learn More

Featured Trial

Buy Retatrutide Online Through Celia

Recruiting

Retatrutide (formerly M25) is an investigational peptide being studied for its potential in supporting weight management and metabolic health. It acts on GLP-1, GIP, and glucagon receptors to influence appetite, energy regulation, and fat metabolism.

Conditions:

Healthy

Learn More

Featured Offer

Find the Best GLP-1 Weight Loss Providers (2025)

Recruiting

Cutting-edge GLP-1 treatments like semaglutide and tirzepatide are helping thousands lose weight with medically guided support. But with so many online providers, how do you know which programs are trusted, affordable, and right for you?

We reviewed the top GLP-1 brands of 2025 — comparing pricing, prescription process, shipping, pharmacy partners, and real user ratings — to help you find a safe, convenient, and effective path toward your weight-loss goals.

- 100% online programs
- Licensed U.S. clinicians
- Fast shipping & flexible payments

See the rankings & choose the GLP-1 provider that fits your life.

Conditions:

Overweight

Overweight and Obesity

Obesity

Weight Loss

Morbid Obesity

Learn More

Featured Trial

Depression Clinical Trial

Recruiting

Join us in researching a potential investigational treatment for Depression. Reimbursement for study-related expenses may be available to you.

Qualifying participants:
•Are between 18-65
•Have been experiencing a major depressive episode for at least a month

Conditions:

Depression

Major Depressive Disorder

Depressive Disorder

Depressive Symptoms

Depressive Disorder

Learn More

A Study to Evaluate the Effectiveness and Safety of Dysport® for the Prevention of Episodic Migraine in Adults

NCT06047457

Recruiting

The purpose of this study is to understand the safety and effectiveness of the study drug, Dysport® when compared with placebo in preventing episodic migraine. A migraine is a headache with severe throbbing pain or a pulsating sensation, usually on one side of the head, and is often accompanied by feeling or being sick and a sensitivity to bright lights and sound. Episodic Migraine is defined as having less than 15 days of headache a month with at least 6 days with migraine headaches. Migraines are caused by a series of events which cause the brain to get stimulated / activated, which results in the release of chemicals that cause pain. Dysport® is a formulation of Botulinum toxin type A (BoNT-A), a medication that stops the release of these chemical messengers. The study will consist of 3 periods: 1. A 'screening period' of 6 to 12 weeks to assess whether the participant can take part to the study and requires 1 visit. 2. A first Treatment Phase of 24 weeks. On Day 1 and at Week 12 of the first Treatment Phase, participants will receive injections into various muscles across the head, neck, face and shoulders. The injections will contain either a dose "A" or a dose ''B'' of Dysport® or a placebo (an inactive substance or treatment that looks the same as, and is given in the same way as, an active drug or intervention/treatment being studied). Participants will make 4 visits to the clinic in person and have 4 remote (online) visits. 3. A second Treatment Phase of 24 weeks (extension phase). At Week 24 and at Week 36, all participants will get Dysport® (dose "A" or dose "B"). There will be 3 in person visits and 4 remote visits. Participants will need to complete an e-diary and questionnaires throughout the study. Participants will undergo blood samplings, urine collections, physical examinations, and clinical evaluations. They may continue some other medications, but the details need to be recorded. The total study duration for a participant will be up to 60 weeks (approx. 14 months). Read Less

Gender:

ALL

Ages:

18 years and above

Trial Updated:

07/29/2025

Locations: Hope Clinical Research, LLC, Canoga Park, California

Conditions: Episodic Migraine

Learn More ›

A Study to Evaluate the Effectiveness and Safety of Dysport® for the Prevention of Chronic Migraine in Adults

NCT06047444

Recruiting

The purpose of this study is to understand the safety and effectiveness of the study drug, Dysport® when compared with placebo in preventing chronic migraine. A migraine is a headache with severe throbbing pain or a pulsating sensation, usually on one side of the head, and is often accompanied by feeling or being sick and a sensitivity to bright lights and sound. Chronic migraine is defined as having at least 15 days of headache a month with at least 8 of those days being migraine headache days. Migraines are caused by a series of events which cause the brain to get stimulated/activated, which results in the release of chemicals that cause pain. Dysport® is a formulation of Botulinum toxin type A (BoNT-A), a medication that stops the release of these chemical messengers. The study will consist of 3 periods: 1. A 'screening period' of 6 to 12 weeks to assess whether the participant can take part to the study and requires 1 visit. 2. A first Treatment Phase of 24 weeks. On Day 1 and at Week 12 of the first Treatment Phase, participants will receive injections into various muscles across the head, neck, face and shoulders. The injections will contain either a dose "A" or dose "B" of Dysport® or a placebo (an inactive substance or treatment that looks the same as, and is given in the same way as, an active drug or intervention/treatment being studied). Participants will make 4 visits to the clinic in person and have 4 remote (online) visits. 3. A second Treatment Phase of 24 weeks (extension phase). At Week 24 and at Week 36, all participants will get Dysport® (dose "A" or dose "B"). There will be 3 in person visits and 4 remote visits. Participants will need to complete an e-diary and questionnaires throughout the study. Participants will undergo blood samplings, urine collections, physical examinations, and clinical evaluations. They may continue some other medications, but the details need to be recorded. The total study duration for a participant will be up to 60 weeks (approx. 14 months). Read Less

Gender:

ALL

Ages:

18 years and above

Trial Updated:

07/29/2025

Locations: Hope Clinical Research, LLC, Canoga Park, California

Conditions: Chronic Migraine

Learn More ›

A Long-Term Study of Elafibranor in Adult Participants With Primary Biliary Cholangitis

NCT06016842

Recruiting

The participants of this study will have confirmed Primary Biliary Cholangitis (PBC) and cirrhosis (scarring of the liver). PBC is a slowly progressive disease, characterised by damage to the bile ducts in the liver, leading to a build-up of bile acids which causes further damage. The liver damage in PBC may lead to cirrhosis. PBC may also be associated with multiple symptoms. Many patients with PBC may require liver transplant or may die if the disease progresses and a liver transplant is not... Read More

Gender:

ALL

Ages:

18 years and above

Trial Updated:

07/29/2025

Locations: Southern California Research Center, Coronado, California

Conditions: Primary Biliary Cholangitis (PBC)

Learn More ›

A Study to Investigate the Safety, Tolerability, Drug Levels and Drug Effects of BMS-986326 in Adult Participants With Different Forms of Lupus

NCT06013995

Recruiting

The purpose of this study is to evaluate safety, drug levels and drug effects on cells and organs of the body, after receiving multiple increasing doses of BMS-986326 via intravenous (IV) infusion or subcutaneous (SC) injection, in participants with different forms of lupus.

Gender:

ALL

Ages:

Between 18 years and 75 years

Trial Updated:

07/29/2025

Locations: Local Institution - 0048, San Diego, California

Conditions: Lupus

Learn More ›

NLP-Based Feedback to Improve Risk Comms and Informed Shared Decision Making

NCT05923684

Recruiting

In this pilot study, the investigators will show feasibility of the NLP-based feedback system in 20 consultations of men with newly diagnosed prostate cancer. The investigators will recruit from the practices of up to 10 physicians who typically see these patients. The investigators will report the top five sentences from each consultation across key content areas (cancer prognosis, life expectancy, erectile dysfunction, urinary incontinence, and irritative urinary symptoms) to both patients and... Read More

Gender:

MALE

Ages:

18 years and above

Trial Updated:

07/29/2025

Locations: Cedars-Sinai Medical Center, Los Angeles, California

Conditions: Prostate Cancer

Learn More ›

Project 2: Optimizing Engagement and Outcomes in STAND Digital Therapy

NCT05908565

Recruiting

The goal is to optimize peer coaching in order to optimize engagement and outcomes in digital therapy. The unmet mental health needs of community college students are staggering and a growing body of research demonstrates that therapy provided digitally with the assistance of trained community members without advanced degrees in mental health is an effective and scalable way to address these needs. Despite being effective for improving symptoms and functioning in those who engage in it, uptake a... Read More

Gender:

ALL

Ages:

Between 18 years and 40 years

Trial Updated:

07/29/2025

Locations: East Los Angeles College, Los Angeles, California

Conditions: Depression, Anxiety

Learn More ›

Using Indoor Air Filtration to Slow Atherothrombosis Progression in Adults With Ischemic Heart Disease History

NCT05867381

Recruiting

This double-blind, randomized, crossover trial aims to test the hypothesis that longer-term indoor air filtration intervention can slow atherothrombosis progression by reducing indoor fine particulate matter (PM2.5) exposure in adults with ischemic heart disease history.

Gender:

ALL

Ages:

Between 65 years and 84 years

Trial Updated:

07/29/2025

Locations: Keck School of Medicine, University of Southern California, Los Angeles, California

Conditions: Air Pollution, Atherosclerosis

Learn More ›

Carboplatin Chemotherapy Before Surgery for People With High-Risk Prostate Cancer and an Inherited BRCA1 or BRCA2 Gene Mutation

NCT05806515

Recruiting

This phase II trial tests how well carboplatin before surgery works in treating patients with high-risk prostate cancer and an inherited BRCA1 or BRCA2 gene mutation. Carboplatin is in a class of medications known as platinum-containing compounds. It works in a way similar to the anticancer drug cisplatin, but may be better tolerated than cisplatin. Carboplatin works by killing, stopping, or slowing the growth of tumor cells. Giving carboplatin before surgery may shrink tumors in patients with h... Read More

Gender:

MALE

Ages:

18 years and above

Trial Updated:

07/29/2025

Locations: Mission Hope Medical Oncology - Arroyo Grande, Arroyo Grande, California

Conditions: Prostate Adenocarcinoma, Stage IIIB Prostate Cancer AJCC v8, Stage IIIC Prostate Cancer AJCC v8

Learn More ›

Atezolizumab Immunotherapy With or Without Tiragolumab for Patients With Unresectable Stage III NSCLC

NCT05798663

Recruiting

This is a phase II trial of neoadjuvant and adjuvant atezolizumab with or without tiragolumab in conjunction with chemoradiotherapy for unresectable stage III NSCLC.

Gender:

ALL

Ages:

18 years and above

Trial Updated:

07/29/2025

Locations: University of California San Diego Moores Cancer Center, La Jolla, California

Conditions: NSCLC

Learn More ›

Study of VGA039 in Healthy Volunteers and Patients With Von Willebrand Disease (VIVID)

NCT05776069

Recruiting

The VIVID study is structured in a master protocol format comprised of multiple parts that evaluate intravenous (IV) and subcutaneous (SC) VGA039 in healthy volunteers and subjects with von Willebrand Disease (VWD) and other bleeding disorders.

Gender:

ALL

Ages:

Between 12 years and 60 years

Trial Updated:

07/29/2025

Locations: Orthopedic Institute for Children (UCLA), Los Angeles, California

Conditions: Von Willebrand Diseases

Learn More ›

HEPA, PM2.5, and Cardiometabolic Health

NCT05718245

Recruiting

The goal of this randomized, double-blind, crossover trial is to test the hypothesis that a longer-term indoor HEPA filtration intervention can improve cardiometabolic profiles by reducing indoor PM2.5 exposures in at-risk individuals.

Gender:

ALL

Ages:

Between 65 years and 84 years

Trial Updated:

07/29/2025

Locations: Keck School of Medicine, University of Southern California, Los Angeles, California

Conditions: Air Pollution, Cardiometabolic Health

Learn More ›

S.T.A.N.D. Alacrity Center Signature Project

NCT05591937

Recruiting

The purpose of this study is to evaluate clinical decision-making algorithms for (a) triaging to level of care and (b) adapting level of care in a low income, highly diverse sample of community college students at East Los Angeles College (ELAC). The target enrollment is 200 participants per year, for five years (N=1000). Participants are between the ages of 18 and 40 years and will be randomized into either symptom severity decision-making (SSD) or data-driven decision-making (DDD). Participan... Read More

Gender:

ALL

Ages:

Between 18 years and 40 years

Trial Updated:

07/29/2025

Locations: East Los Angeles College, Los Angeles, California

Conditions: Depression, Anxiety

Learn More ›

Kaiser Permanente houses over 6,000 physicians in southern California and it is also one of the largest research centers on the state. On its clinical trial division, Kaiser Permanente conducts clinical trials of almost every specialty funded by pharmaceutical companies, government, and foundations.

The Cedars-Sinai Medical Center located in Los Angeles is one of the largest research centers owned and operated by a private hospital in the United States. Focusing on biomedical, cancer, and heart research among other specialties, you can find almost any type of clinical trials for both health and non-healthy volunteers at the research division of Cedar-Sinai Medical Center.

There are around 100,000 clinical trials happening every year across the United States about almost every condition out there. While most clinical trials are testing drugs or medical devices there are also many behavioral and observational trials going on at any point in time. Many paid research studies are held at these California locations.

Clinical trials are incredibly important for making new medical and scientific discoveries, finding new and better methods for diagnosing medical conditions early, testing new interventions, and even developing safer and more effective surgical procedures.

In order for all these discoveries to me made available to the general population they need to go through years of rigorous testing both in healthy and non-healthy volunteers. During those years, medical professionals follow a protocol that has been previously approved by the FDA or other regulatory agency to test the effectiveness and safety of their discovery.

Other people choose to participate in a clinical trial because they feel it is a good way to contribute to the advancement of medical knowledge and that their participation can help many people in the future. The following lists of trials are broken down by condition, and to find a specific clinical trial in your area click through to clinicaltrials.gov.