Clinical trials · California
Breast cancer clinical trials in California
We’re tracking 244 recruiting breast cancer studies with a site in California — including Early Phase 1, Phase 1, Phase 1/Phase 2, Phase 2, Phase 3 and Phase 4 studies, each written for real people, not researchers.
Recruiting studies in California
- NCT06022029RecruitingPhase 1
Study of injected ONM-501 alone or with cemiplimab for advanced cancers
This trial tests an injected study drug (ONM-501) alone or with another drug (cemiplimab) for people with advanced solid tumors or lymphomas that haven't responded to other treatments. It aims to find a safe dose and see if the combination helps shrink or control the cancer.
Los Angeles, CaliforniaAges 18 years+ - NCT07046923RecruitingPhase 1
A study of LY4175408 for advanced cancer
This trial tests a new targeted drug (LY4175408) for people with certain advanced solid tumors (lung, endometrial, or triple negative breast cancer) who have already tried standard treatments. The goal is to see if the drug is safe and effective.
Stanford, CaliforniaAges 18 years+ - NCT07357597RecruitingPhase 4
Preventing mouth sores during breast or lung cancer treatment
This trial tests whether a steroid mouthwash can prevent mouth sores caused by the drug Datopotamab Deruxtecan (Dato-DXd). It is for people with certain types of advanced breast cancer or lung cancer who are about to start Dato-DXd for the first time.
Glendale, CaliforniaAges 18 years+ - NCT04049214Recruiting
Mindfulness program during breast cancer surgery
This trial tests whether a structured mindfulness program before and after breast cancer surgery can reduce stress and improve how patients feel and cope. You may be offered mindfulness materials to use around the time of your operation.
Newport Beach, CaliforniaAges 18 years+ - NCT07677839Recruiting
Study using ultrasound to look at normal lymph nodes before breast surgery
This study uses a special type of ultrasound (UHFUS) to take detailed images of your lymph nodes before and during breast cancer surgery. The goal is to better understand normal lymph node anatomy, which may help prevent lymphedema (swelling) after surgery.
Sacramento, CaliforniaAges 18 years+ - NCT07616856Recruiting
Evaluating LumiSystem for cancer surgery margins
This study tests a device called LumiSystem that helps doctors check if all cancer cells are removed during breast cancer surgery. The goal is to see if using it improves surgery outcomes.
Palo Alto, CaliforniaAges 18 years+ - NCT07071896Recruiting
Video exercise program for breast cancer survivors
This study tests a video-based exercise program for people who recently had breast cancer surgery. It aims to help with recovery by providing guided exercises you can do at home.
San Diego, CaliforniaAges 18 years+ - NCT06993844RecruitingPhase 1/Phase 2
Study of ETX-636 for advanced solid tumors with PIK3CA mutation
This trial tests an experimental drug called ETX-636 in people whose cancer has a specific gene change (PIK3CA mutation) and has not responded to at least one prior treatment. The goal is to see if the drug can shrink tumors or stop them from growing.
Newport Beach, CaliforniaAges 18 years+ - NCT06908928RecruitingPhase 1
Study of Bulumtatug Fuvedotin for advanced triple-negative breast cancer
This study tests a new drug called bulumtatug fuvedotin for people with triple-negative breast cancer that has spread or come back. It's for those who have already tried certain other treatments, including a taxane and a specific type of antibody-drug conjugate.
La Jolla, CaliforniaAges 18 years+ - NCT06648278Recruiting
Support and technology study for breast cancer patients
This trial tests a program called PONTS 2.0 that uses phone texts and online tools to support breast cancer patients through their treatment. It aims to make it easier for patients to get the help they need.
San Francisco, CaliforniaAges 18 years+ - NCT03053193Recruiting
Testing gene activity to guide breast cancer treatment
This study links breast tumor test results from MammaPrint and optional BluePrint (and full genetic data) with real-world clinical information to understand which new gene activity patterns matter. It may help future patients by improving how doctors use these tests to guide care.
Bakersfield, CaliforniaAges 18 years+ - NCT06458712RecruitingPhase 1
Testing a new drug for advanced cancers with gene changes
This study tests a new oral drug, DSB2455, for people with advanced breast, prostate, ovarian, or pancreatic cancers that have certain gene changes. It aims to see if the drug is safe and whether it helps shrink or control the cancer.
Sacramento, CaliforniaAges 18 years+ - NCT06393374RecruitingPhase 3
Study of a new drug combination for residual TNBC after initial treatment
This trial tests a new combination of two drugs (sacituzumab tirumotecan and pembrolizumab) compared to standard chemotherapy for people with triple-negative breast cancer that did not fully respond to initial treatment. It aims to see if this combination helps prevent cancer from coming back.
Fountain Valley, CaliforniaAges 18 years+ - NCT06377852RecruitingPhase 3
CDK4/6 inhibitor dosing study for older adults with metastatic breast cancer
This study tests two targeted therapy drugs, palbociclib and ribociclib, combined with hormone therapy for people aged 60 or older with hormone receptor-positive, HER2-negative metastatic breast cancer. The goal is to see how well this treatment works and to gather information that may help improve dosing for older adults.
Eureka, CaliforniaAges 60 years+ - NCT06353997RecruitingPhase 2
Neoadjuvant INBRX-106 with pembrolizumab for early-stage triple-negative breast cancer
This trial tests whether adding an experimental drug called INBRX-106 to the standard immunotherapy (pembrolizumab) and chemotherapy before surgery can improve outcomes for patients with early-stage triple-negative breast cancer. The goal is to shrink the tumor and potentially reduce the risk of the cancer coming back.
Los Angeles, CaliforniaAges 18 years+ - NCT06123286RecruitingEarly Phase 1
Tart cherry and omega-3s for joint pain from hormone therapy
This study tests whether taking tart cherry and omega-3 supplements can help reduce joint pain and stiffness caused by aromatase inhibitors (a common breast cancer treatment). If you have bothersome joint pain while on this hormone therapy, you may be able to join.
Torrance, CaliforniaAges 18 years+ - NCT05768139RecruitingPhase 1/Phase 2
Testing a new targeted drug for advanced solid tumors with PI3Kα mutation
This trial tests tersolisib, a new targeted medicine, in adults with advanced or hard-to-remove solid cancers. It focuses on tumors that have a specific genetic change (PI3Kα mutation) to see how well the treatment works and what side effects it causes.
Los Angeles, CaliforniaAges 18 years+ - NCT05366699Recruiting
Procedure to help prevent arm swelling after breast surgery
This trial studies a new procedure meant to lower the chance of getting lymphedema (arm swelling) after breast cancer surgery that removes lymph nodes in the armpit. It may help patients reduce the risk of long-term arm swelling, especially after lymph node dissection.
San Francisco, CaliforniaAges 18–75 - NCT05232916RecruitingPhase 3
Vaccine for HER2-positive breast cancer after standard treatment
This trial tests a vaccine (GLSI-100) that may help prevent the return of HER2-positive breast cancer. It is given to patients who still had cancer cells after initial treatment with trastuzumab, or who had stage III disease and achieved a complete response.
Duarte, CaliforniaAges 18–100 - NCT05059444Recruiting
Blood test to catch cancer early after treatment
This study looks for signs of cancer left in the body after treatment using a simple blood test (called a liquid biopsy). It aims to see if the test can catch cancer that might come back earlier than regular scans.
Sacramento, CaliforniaAges 18 years+ - NCT07114601RecruitingPhase 1
Study of LY4257496 for people with GRPR-positive solid tumors
This trial tests a new drug, LY4257496, in people with certain types of cancer that have a protein called GRPR on their cells. The study aims to see if the drug can help shrink tumors or slow the cancer's growth.
Duarte, CaliforniaAges 18 years+ - NCT06995898Recruiting
Blood test study for early cancer detection
This study is testing a new blood test that may help find cancer early. You will give blood samples over a year, and researchers will check them for signs of cancer.
Pleasanton, CaliforniaAges 45–75 - NCT05978128Recruiting
Use advocates to boost lung cancer screening
This trial tests whether trained advocates and supporters can help people who are eligible for lung cancer screening actually get screened. It may help you (and others) by making screening easier to plan and complete.
Los Angeles, CaliforniaAges 40–80 - NCT06418204Recruiting
Cannabis use among cancer patients in community clinics
This study looks at how cancer patients use cannabis (marijuana) and cannabis products to manage symptoms during chemotherapy or immunotherapy. The goal is to learn about the benefits and risks so doctors can better guide patients.
Antioch, 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.
- Hoag Memorial Hospital Presbyterian · 3 studies
- Providence Medical Foundation - Santa Rosa · 3 studies
- City of Hope · 2 studies
- Kaiser Permanente-Oakland · 2 studies
- Kaiser Permanente-Roseville · 2 studies
- Kaiser Permanente-Vallejo · 2 studies
- Kaiser Permanente-Walnut Creek · 2 studies
- Adventist Health - Bakersfield
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 244 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.