Clinical trials · California
Gut Microbiome clinical trials in California
We’re tracking 8 recruiting gut microbiome studies with a site in California, each written for real people, not researchers.
Recruiting studies in California
- NCT04359836Recruiting
Study of gut bacteria in early COVID-19
This trial studies how gut bacteria (“gut flora”) may affect COVID-19 after a recent infection. If you test positive for COVID-19 soon enough, the study may help researchers understand why some people get better faster or have different symptoms.
Ventura, CaliforniaAges 18 years+ - NCT07567794Recruiting
Gut-Brain Connection Study in Parkinson's Disease
This research examines how the gut and brain are connected in Parkinson's disease and aims to better understand the disease. You'd participate in visits and tests over three years, including some involving your digestive system.
Stanford, CaliforniaAges 21–80 - NCT06800833Recruiting
Mango or cookie study for gut, mental, sexual, and skin health
This study is testing whether eating mangoes or low-fat cookies every day for 4 weeks can improve your gut health, and in turn affect your mood, sex life, and skin. If you are generally healthy, not pregnant, and not taking certain medications or supplements, you may be able to join.
San Diego, CaliforniaAges 18–50 - NCT06221800Recruiting
Gut bacteria and lung cancer treatment side effects study
This study looks at how the bacteria in your gut (microbiome) might affect how well your lung cancer treatment works and what side effects you experience. The goal is to learn if certain gut bacteria can predict treatment response or side effects for people with advanced non-small cell lung cancer.
Orange, CaliforniaAges 18 years+ - NCT03325855Recruiting
Fecal transplant registry for patients and donors
This study is a national “registry” that collects information from people who get fecal microbiota transplant (a stool-based treatment) and from people who donate stool. It helps researchers understand who receives these treatments and how they do over time.
Ventura, CaliforniaAges Any age - NCT04775355Recruiting
Track urine and gut changes during prostate cancer treatment
This study looks at how your urine and gut (intestine) microbes change while you undergo prostate cancer treatments, including hormone therapy (androgen deprivation) and/or radiation. The goal is to better understand these biological changes, which may help improve future treatment planning.
Duarte, CaliforniaAges 18 years+ - NCT06361524Enrolling by invitation
Gut bacteria study in chronic heart failure
This study looks at the bacteria in your gut (your 'gut microbiome') and how it relates to chronic heart failure. It may help doctors understand why some people with heart failure do better than others and could lead to better treatments in the future.
Stanford, CaliforniaAges 18–75 - NCT07437911Recruiting
Can a Supplement Help with Nutrient Gaps for GLP-1 Users?
This study tests whether a daily supplement can help fill nutrient gaps and improve gut health for people who are already taking GLP-1 weight-loss medications (like Ozempic or Wegovy). Participants must be on a stable dose for at least 8 weeks and be generally healthy without other chronic conditions.
Santa Monica, CaliforniaAges 18–59
Where these studies are running in California
Institutions with a site for the recruiting gut microbiome studies listed above.
- Stanford University · 3 studies
- Children's Hospital Los Angeles
- Citruslabs
- City of Hope Comprehensive Cancer Center
- ProgenaBiome
- San Diego State University
- Sutter Roseville Medical Center
- University of California, Irvine Medical Center / UC Irvine Health
What taking part in a gut microbiome study involves
A screening visit first
Before anything else, the study team checks whether you fit — usually a visit with some tests. You can stop at any point, and screening is typically free.
Care at a nearby site
Study visits happen at a clinic or hospital taking part. Many studies cover the cost of the study treatment and related visits, and some reimburse travel.
You stay in control
Taking part is voluntary and you can leave a study at any time, for any reason, without affecting your regular care.
The team decides eligibility
Our fit check is a helpful first read, not a decision. The study team makes the final call after reviewing your health history.
Gut Microbiome trials in other states
Common questions
- Are there gut microbiome clinical trials in California?
- Yes. We're currently tracking 8 recruiting gut microbiome studies with a site in California, each rewritten in plain language so you can see what it's testing and who it's for.
- How do I find out if I qualify for a gut microbiome study in California?
- Each study lists its eligibility rules — age, diagnosis, prior treatments. On every trial page we explain these in plain language and offer a short, optional pre-screen for a fit read. The study team makes the final decision.
- Do I have to live in California to take part?
- Not necessarily. These studies have a site in California, but eligibility is about your health, not your address — some people travel to take part, and a few studies reimburse travel. The study team can tell you what's required.
- Does it cost anything to join a gut microbiome trial?
- Using Clin2 is always free. Many trials cover the study treatment and related visits; some reimburse travel. The study team explains exactly what's covered before you decide.
Not the right time?
New gut microbiome studies open in California regularly. Set up a health profile and we’ll quietly watch for studies that fit you and email you when one opens.
Clin2 helps you find and understand clinical trials and does not provide medical advice. Study data comes from ClinicalTrials.gov. Talk with your doctor about whether a specific trial is right for you.