Clinical trials · California
Breast cancer clinical trials in California
We’re tracking 237 recruiting breast cancer studies with a site in California — including Phase 1, Phase 1/Phase 2 and Phase 2 studies, each written for real people, not researchers.
Recruiting studies in California
- NCT06774027Recruiting
Breast cancer antibody-drug conjugate treatment registry
This study tracks how well antibody-drug conjugates (ADCs) work for breast cancer that has spread. You may join if you are about to start your first or second ADC for hormone receptor-positive/HER2-negative or triple-negative breast cancer.
San Francisco, CaliforniaAges 18 years+ - NCT06780176Recruiting
Breast cancer risk study for people in Florida
This study looks at breast cancer risk factors and outcomes by inviting people who are getting breast biopsies or are new breast patients at certain Florida hospitals to complete a survey. It aims to better understand what affects breast cancer risk and treatment results.
Los Angeles, CaliforniaAges 18 years+ - NCT06797635RecruitingPhase 2
Study of Patritumab Deruxtecan and Pembrolizumab for High-Risk Early Breast Cancer
This trial tests a combination of targeted therapies (patritumab deruxtecan plus pembrolizumab) along with other anticancer drugs for people with a high-risk type of early-stage breast cancer that is either triple-negative or has very low hormone receptors and is HER2-negative. The goal is to see if this approach can help prevent the cancer from coming back.
Santa Monica, CaliforniaAges 18 years+ - NCT06860815RecruitingPhase 2
Cemiplimab with liver radiation for breast cancer that spread to the liver
This trial tests a combination of a drug called cemiplimab (an immunotherapy that helps your immune system fight cancer) and a type of targeted radiation (Y-90 SIR-Spheres) given directly to liver tumors. It is for people with breast cancer that has spread to the liver and who have already had at least one type of chemotherapy.
Duarte, CaliforniaAges 18 years+ - NCT06896474Recruiting
Breast cancer treatment choice help for women 70 and older
This study tests a decision aid to help women 70 and older with early stage breast cancer choose their treatment. It looks at whether the tool helps patients and their doctors make a confident treatment choice.
Los Angeles, CaliforniaAges 18 years+ - NCT06910761RecruitingPhase 2
Radiation for cancer spread to brain lining
This trial tests whether a precise type of radiation to the brain and spine (craniospinal irradiation) can help control cancer that has spread to the lining of the brain and spinal cord (leptomeningeal disease) in people with breast cancer or non-small cell lung cancer. The goal is to improve symptoms and slow disease progression.
Irvine, CaliforniaAges 18 years+ - NCT06943521RecruitingPhase 1/Phase 2
Study of MT-4561 for advanced solid tumors
This trial tests a new drug called MT-4561 in people with advanced solid tumors that have not responded to prior treatments. It aims to see if the drug can help shrink tumors or slow their growth.
Los Angeles, CaliforniaAges 18 years+ - NCT06954831RecruitingPhase 2
Short-course radiation for early-stage breast cancer
This trial tests a shorter, more intense radiation schedule for people with stage I-III breast cancer after lumpectomy. It aims to find if giving a higher daily dose over fewer sessions is safe and effective.
Arcadia, CaliforniaAges 40 years+ - NCT06966453RecruitingPhase 1/Phase 2
Study of disitamab vedotin for HER2-positive advanced breast cancer
This study tests a new drug called disitamab vedotin for people with advanced breast cancer that has a certain amount of HER2 protein. Depending on your HER2 and hormone receptor status, you may be eligible for one of three groups, each with different prior treatment requirements.
Anaheim, CaliforniaAges 18 years+ - NCT07029399RecruitingPhase 1
Study of NKT5097 for advanced solid tumors
This trial tests an experimental oral drug (NKT5097) for people with advanced solid tumors that have not responded to other treatments. It may also be an option for people with a specific type of breast cancer (HR+/HER2-). The goal is to see if the drug is safe and effective.
La Jolla, CaliforniaAges 18 years+ - NCT07054190RecruitingPhase 2
Testing Inavolisib in early-stage breast cancer with PIK3CA mutation
This trial is testing a drug called Inavolisib (a type of targeted therapy) given before surgery for people with early-stage, hormone receptor-positive, HER2-negative breast cancer that has a specific genetic change (PIK3CA mutation). The goal is to see if adding Inavolisib to standard endocrine therapy can shrink the tumor more effectively.
Los Angeles, CaliforniaAges 18 years+ - NCT07208084Recruiting
A support program for Black women with breast cancer
This study tests a program called Project SOAR that offers group support and education for Black American women with breast cancer. It aims to help them feel more empowered and connected during their journey.
Los Angeles, CaliforniaAges 18 years+ - NCT07211178Recruiting
Tracking cancer DNA in blood to detect early return of breast cancer
This study tracks tiny traces of cancer DNA in the blood over time to see if it can find early signs of breast cancer coming back. It looks at different types of breast cancer and at different points in a patient's treatment journey.
Whittier, CaliforniaAges 18–99 - NCT07227233RecruitingPhase 2
AI-guided retrial of CDK4/6 inhibitors for advanced breast cancer
This trial tests whether an artificial intelligence (AI) tool can help doctors decide if it is safe and effective to give you a second course of a CDK4/6 inhibitor drug (like palbociclib, ribociclib, or abemaciclib) plus hormone therapy for advanced (unresectable or metastatic) HR+/HER2- breast cancer. The goal is to only treat people whose cancer is likely to respond based on a special AI analysis of their tumor tissue.
La Jolla, CaliforniaAges 18 years+ - NCT07059884Recruiting
Exercise program to help people with cancer stay active
This trial tests a distance-based exercise program designed to help people on chemotherapy maintain their physical function and prevent disability. It is for patients with certain cancers who are working full-time and can participate in moderate physical activity.
Dublin, CaliforniaAges 18 years+ - NCT07524322RecruitingPhase 1
RGT-490 for Advanced Cancers With PIK3CA Mutations
This study tests a new drug called RGT-490 in patients with advanced solid tumors (cancers that have spread or cannot be removed by surgery) that have a specific genetic change called a PIK3CA mutation. The drug is designed to block a protein involved in cancer cell growth.
Los Angeles, CaliforniaAges 18 years+ - NCT01042379RecruitingPhase 2
Adaptive drug trial for newly diagnosed breast cancer
This study tests personalized, changing treatment plans (given before surgery) to find better options for your specific breast tumor. You may be asked for extra breast-tissue testing to help match you with the most suitable study drug(s).
San Francisco, CaliforniaAges 18 years+ - NCT01035112Recruiting
MRI check for suspicious breast changes
This study uses a breast MRI scan to look at suspicious areas in the breast. It may help doctors better tell which breast changes need closer follow-up like a biopsy.
Stanford, CaliforniaAges 21 years+ - NCT01766297RecruitingPhase 2
Proton radiation after lumpectomy for early breast cancer
This trial studies a type of radiation made with protons to treat only part of the breast after surgery (lumpectomy) for early-stage breast cancer. It may help control the cancer while aiming to reduce radiation to surrounding tissues.
San Diego, CaliforniaAges 50 years+ - NCT02620852Recruiting
Wisdom Study: Women’s breast cancer screening decisions
This study looks at how to decide the best breast cancer screening (like mammograms) based on your personal risk. It may help by testing a smarter way to match screening to your risk level.
Los Angeles, CaliforniaAges 30–74 - NCT05377996RecruitingPhase 1/Phase 2
Study drug for advanced solid tumors with tumor tissue testing
This early-stage study tests emiltatug leda-dotin (Emi-Le) in people with advanced or recurring solid cancers. It aims to see how the drug works and how safely it can be given, using tumor tissue testing to help understand who may benefit.
Santa Monica, CaliforniaAges 18 years+ - NCT07505797Recruiting
Ultrasound imaging study for suspicious breast lesions
This study is testing a new ultrasound device (ATUSA) to see how well it can image breast lesions that have been classified as suspicious (BI-RADS 4 or 5). If you have a recent finding that needs further evaluation, this research might help improve detection methods.
Sacramento, CaliforniaAges 18–94 - NCT06583395Enrolling by invitation
Meditation retreat study with fitness tracker
This trial studies people attending a 7-day meditation retreat to see how meditation affects well-being. You will wear a fitness tracker and answer surveys.
Palm Desert, CaliforniaAges 21 years+ - NCT03424005RecruitingPhase 1/Phase 2
Testing new drug combinations for advanced breast cancer
This study tests how well and how safely different combinations of cancer drugs work for people with metastatic or inoperable locally advanced breast cancer. It may help by finding a better treatment option and collecting information to guide future care.
Duarte, CaliforniaAges 18 years+
Breast cancer trials by city in California
Where these studies are running in California
Institutions with a site for the recruiting breast cancer studies listed above.
- City of Hope Comprehensive Cancer Center · 7 studies
- University of California, San Francisco · 4 studies
- City of Hope Orange County Lennar Foundation Cancer Center · 3 studies
- University of California San Diego Health · 3 studies
- University of California, Los Angeles (UCLA) · 3 studies
- Los Angeles Cancer Network · 2 studies
- Stanford Cancer Institute · 2 studies
- UC San Diego Moores Cancer Center · 2 studies
What taking part in a breast cancer 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.
Breast cancer trials in other states
Common questions
- Are there breast cancer clinical trials in California?
- Yes. We're currently tracking 237 recruiting breast cancer 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 breast cancer 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 breast cancer 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 breast cancer 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.