Clinical trials · California
Breast cancer clinical trials in California
We’re tracking 244 recruiting breast cancer studies with a site in California — including 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
- NCT05856773RecruitingPhase 3
Comparing two proton therapy schedules for breast cancer
This trial compares two ways of giving proton therapy to the breast or chest wall and nearby lymph nodes after surgery. The goal is to see if a shorter course of treatment works just as well as the standard longer course, while possibly reducing side effects.
San Diego, CaliforniaAges 19 years+ - NCT05646862RecruitingPhase 3
Comparing two treatments for advanced breast cancer with a PIK3CA mutation
This trial tests whether a new drug combo (inavolisib plus fulvestrant) works better than an existing one (alpelisib plus fulvestrant) for people with a specific type of advanced breast cancer that has a PIK3CA mutation. It aims to find a treatment that may help control the cancer longer.
Los Angeles, CaliforniaAges 18 years+ - NCT00477100Recruiting
Breast cancer tissue and data registry for research
This trial helps create a research “tissue registry” by collecting breast cancer tissue samples and medical information. It may help doctors better understand inflammatory or invasive breast cancer and improve future studies.
La Jolla, CaliforniaAges 18 years+ - NCT05005403RecruitingPhase 1
Testing azirkitug for lung, head/neck, and other solid cancers
This Phase 1 study tests how a new medicine (azirkitug) behaves in the body and how safe it is, given by IV infusion alone or with other cancer drugs. It may help people with several advanced solid tumor cancers, especially after standard treatments have stopped working.
Duarte, CaliforniaAges 18 years+ - NCT06934239RecruitingPhase 4
AI-assisted vs. standard mammograms for breast cancer screening
This trial compares standard mammograms with mammograms aided by artificial intelligence (AI) to see if AI helps find breast cancer more accurately and reduces unnecessary callbacks. If you're 18 or older and getting a routine screening mammogram at one of the six participating health systems, you may be eligible.
Los Angeles, CaliforniaAges 18 years+ - NCT04020575RecruitingPhase 1
CAR T cells made from your blood for advanced breast cancer
This Phase 1 trial tests CAR T cells made from your own immune cells to target advanced breast cancer. The cells are designed to recognize a specific cancer marker (called MUC1*), with the goal of shrinking tumors or keeping them under control.
Duarte, CaliforniaAges 18 years+ - NCT06764940RecruitingPhase 2
Utidelone and capecitabine for HER2-negative breast cancer with brain metastases
This trial tests if the combination of Utidelone and capecitabine can shrink brain metastases in people with HER2-negative breast cancer. It is designed for those whose cancer has spread to the brain and who have not had many prior treatments.
San Diego, CaliforniaAges 18 years+ - NCT06422455Recruiting
Genetic testing for underserved cancer patients
This study offers free genetic testing to cancer patients and their healthcare providers. It aims to help people who may not have easy access to genetic testing understand their cancer risk.
Los Angeles, CaliforniaAges 18 years+ - NCT07109726RecruitingPhase 1/Phase 2
Testing TER-2013 for advanced tumors with AKT/PI3K/PTEN changes
This trial tests a new drug called TER-2013, alone or combined with another drug (fulvestrant), for people with advanced solid tumors that have specific genetic changes in the AKT/PI3K/PTEN pathway. It aims to see if the drug is safe and effective.
Irvine, CaliforniaAges 18 years+ - NCT07671937Recruiting
Sharing patient feedback in cancer care team meetings
This study gathers your feedback (like symptoms and quality of life) and shares it with your cancer care team during their group meetings, so they can better tailor your care. It is for people recently diagnosed with pancreatic, breast, or gynecologic cancer and aims to make sure your voice is heard in treatment decisions.
Los Angeles, CaliforniaAges 18 years+ - NCT04888975Recruiting
Device study for one-arm swelling after lymph surgery
This study tests a medical device (Dayspring Technology) to reduce swelling in the arm caused by breast cancer treatment and lymph surgery. You may be eligible if you have one-sided arm swelling after lymphatic surgery and meet safety checks for the device.
Palo Alto, CaliforniaAges 18 years+ - NCT07062965RecruitingPhase 3
PF-07248144 with fulvestrant for HR+ HER2- advanced breast cancer
This trial tests a new study medicine (PF-07248144) combined with fulvestrant in people with a certain type of advanced breast cancer (HR-positive, HER2-negative) that has worsened after previous treatments. It may be an option if you've already tried a CDK4/6 inhibitor and endocrine therapy.
Camarillo, CaliforniaAges 18 years+ - NCT05645536Enrolling by invitationPhase 3
Safety follow-up for hormone-positive, HER2-negative breast cancer
This trial studies the safety of continuing endocrine therapy with ovarian suppression (for women) after you finish the earlier OVELIA study. It may help doctors confirm that the treatment remains safe for longer-term use.
Greenbrae, CaliforniaAges 18–51 - NCT04802759RecruitingPhase 1/Phase 2
Testing drug combinations for recurrent or advanced ER-positive breast cancer
This early-phase trial tests several combinations of cancer medicines to slow or control ER-positive breast cancer that has returned or progressed. It also checks safety and whether tumor or blood biomarkers can help match the right treatment to the right person.
Duarte, CaliforniaAges 18 years+ - NCT04722341Recruiting
Time-limited eating for people with certain breast or rectal cancers
This study tests whether eating only within a shorter daily time window can improve cancer outcomes in people with specific breast or rectal cancers. It also looks at how this affects the body (such as metabolism) and who is most likely to benefit.
West Hollywood, CaliforniaAges 18 years+ - NCT07546331Recruiting
Body Composition and Breast Reconstruction Outcomes
This study measures body composition (muscle and fat distribution) in patients undergoing breast reconstruction after mastectomy to understand how these measurements relate to surgical outcomes and recovery. Understanding these connections may help doctors better predict and optimize results for future patients.
San Francisco, CaliforniaAges 18 years+ - NCT05386108RecruitingPhase 1/Phase 2
Test abemaciclib plus elacestrant for breast cancer brain spread
This trial studies whether the combination of abemaciclib and elacestrant can slow or shrink ER-positive, HER2-negative breast cancer that has spread to the brain. It is designed for people whose cancer has progressed despite prior hormone (endocrine) treatment.
Fullerton, CaliforniaAges 18 years+ - NCT04981119Recruiting
Test apheresis for CAR T manufacturing in HLA-A2 solid tumors
This trial studies how a process called apheresis is used to make CAR T cells for people with certain solid tumors. It is designed for tumors that have lost a specific immune marker (HLA-A*02), which may affect how well CAR T therapies work.
Santa Monica, CaliforniaAges 18 years+ - NCT06726148RecruitingPhase 1/Phase 2
Study of ECI830 for advanced breast cancer and solid tumors
This trial is testing a new drug called ECI830, either alone or with another drug, for people with advanced breast cancer or other solid tumors that have not responded to standard treatments. It may be an option if you have HR+/HER2- breast cancer, small cell lung cancer, or a tumor with a specific gene change (CCNE1 amplification).
Los Angeles, CaliforniaAges 18–100 - NCT04503265RecruitingPhase 1/Phase 2
AMXI-5001 study for advanced cancers that won’t respond
This Phase 1/2 trial tests AMXI-5001 in people with advanced cancers that have progressed or stopped responding to standard treatments. It’s mainly designed to find the safest dose and see early signs the treatment might work.
Los Angeles, CaliforniaAges 18 years+ - NCT07629206Recruiting
Freezing therapy for small, early-stage breast cancer
This study tests whether freezing a small breast tumor (cryoablation) is a safe and effective treatment option for older adults with early-stage, hormone-receptor-positive breast cancer. Instead of surgery, the goal is to destroy the tumor by freezing it in place.
Glendale, CaliforniaAges 70 years+ - NCT05879926RecruitingPhase 3
Testing chemo after hormone therapy in premenopausal early breast cancer
This Phase 3 trial checks whether adding chemotherapy after standard hormone-blocking treatment works better for some premenopausal women with early-stage, ER-positive, HER2-negative breast cancer. It targets patients with limited lymph node spread and a lower-to-intermediate tumor “recurrence” risk score.
San Francisco, CaliforniaAges 18–60 - NCT05872295RecruitingPhase 1
Study drug for HER2-positive advanced cancers
This Phase 1 trial tests IKS014 to see how safe it is and how well it works in advanced solid tumors that have HER2. You may be eligible if your tumor is HER2-positive (including certain “low HER2” types) and your body’s blood counts and organ function are strong enough.
Newport Beach, CaliforniaAges 18 years+ - NCT07218003Enrolling by invitationPhase 1
Study of RNDO-564 alone or with pembrolizumab for bladder cancer
This trial tests an experimental drug, RNDO-564, either by itself or combined with another drug (pembrolizumab), for people with advanced bladder cancer or other solid tumors that have stopped responding to standard treatments. The goal is to see if it can shrink tumors or slow cancer growth.
San Francisco, 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 · 5 studies
- Cedars-Sinai Medical Center · 2 studies
- Scripps Health · 2 studies
- Stanford University · 2 studies
- USC Norris Comprehensive Cancer Center · 2 studies
- Alta Bates Summit Medical Center-Herrick Campus
- California Pacific Medical Center
- California Protons Cancer Therapy Center
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.