Clinical trials · California
HER2-negative Breast Cancer clinical trials in California
We’re tracking 37 recruiting her2-negative breast cancer studies with a site in California — including Phase 1, Phase 1/Phase 2, Phase 2 and Phase 3 studies, each written for real people, not researchers.
Recruiting studies in California
- NCT07391774RecruitingPhase 3
Hormone therapy with or without chemo for early breast cancer
This trial tests whether skipping chemotherapy and using only hormone therapy with a drug called ribociclib works as well as chemotherapy followed by hormone therapy with ribociclib for certain early breast cancers that have a low risk of coming back.
Auburn, CaliforniaAges 18 years+ - NCT04893109RecruitingPhase 2
Study compares two HER2 breast cancer treatments after surgery
This Phase 2 study tests two different medicines given after breast surgery to reduce the risk of cancer coming back. It is only for people with early-stage HER2-positive breast cancer with limited or no lymph node spread.
San Francisco, CaliforniaAges 18 years+ - NCT06058377RecruitingPhase 3
Adding immunotherapy to chemo for stage II-III breast cancer
This trial tests whether adding the immunotherapy drug durvalumab to standard chemotherapy works better than chemo alone for people with hormone receptor positive, HER2 negative breast cancer that is stage II or III and has a high-risk genetic score (MammaPrint High Risk 2).
Auburn, CaliforniaAges 18 years+ - NCT06492616RecruitingPhase 3
Elacestrant vs standard hormone therapy for high-risk early breast cancer
This trial tests a new hormone therapy pill (elacestrant) against standard hormone therapy for people with a common type of early breast cancer (ER+, HER2-) that has a higher chance of returning. You may qualify if you've already been on hormone therapy for 2 to 5 years and want to see if a different pill works better.
Bakersfield, CaliforniaAges 18 years+ - NCT05304962RecruitingPhase 1
Test drug RGT-419B for advanced ER+ HER2- breast cancer
This Phase 1 study tests a new drug (RGT-419B), given alone or with hormone (endocrine) therapy, in people with advanced ER-positive, HER2-negative breast cancer that has progressed after standard treatments. It looks mainly at safety and early signs of how well the treatment may work.
La Jolla, CaliforniaAges 18 years+ - NCT07647328RecruitingPhase 3
Camizestrant and ribociclib for advanced hormone-receptor-positive breast cancer
This trial tests a combination of two drugs (camizestrant and ribociclib) for advanced breast cancer that is hormone-receptor-positive and HER2-negative. The study aims to see if this combination helps patients whose cancer cannot be surgically removed or treated with radiation alone.
Duarte, CaliforniaAges 18–130 - NCT06042569RecruitingPhase 2
Lower-dose chemo for older women with HER2-negative breast cancer
This trial tests whether a lower dose of two chemotherapy drugs (docetaxel and cyclophosphamide) works well for women 65 and older with early-stage HER2-negative breast cancer. The goal is to maintain effectiveness while reducing side effects in this group.
Duarte, CaliforniaAges 65 years+ - NCT06065748RecruitingPhase 3
New hormone therapy for advanced breast cancer after prior treatment
This trial tests a new oral hormone therapy, giredestrant, against a standard hormone therapy (fulvestrant) when both are given with a CDK4/6 inhibitor. It is for people with advanced ER-positive, HER2-negative breast cancer that has come back after initial hormone therapy, and who have not yet had other treatments for advanced disease.
Auburn, CaliforniaAges 18 years+ - NCT05812807RecruitingPhase 3
Pembrolizumab versus monitoring after triple-negative breast cancer response
This trial checks whether giving pembrolizumab (an immunotherapy) after surgery helps people with triple-negative breast cancer reduce the chance of the cancer coming back, compared with close monitoring only. It’s for patients who had no remaining invasive cancer after neoadjuvant chemotherapy plus pembrolizumab.
Arroyo Grande, CaliforniaAges 18 years+ - NCT05929768RecruitingPhase 3
Shorter chemo plus immunotherapy without anthracyclines for early TNBC
This Phase 3 trial tests whether a shorter course of chemotherapy plus immunotherapy can work as well as standard treatment for early-stage triple-negative breast cancer. It avoids anthracycline drugs and may help reduce exposure to those medicines if the shorter plan is effective and safe.
Berkeley, CaliforniaAges 18 years+ - NCT06380751RecruitingPhase 3
New targeted therapy for BRCA/PALB2-mutated HR+ breast cancer
This trial tests a new combination of targeted therapies (saruparib plus camizestrant or hormone therapy) against standard treatments for people with a specific type of advanced breast cancer. It may be a good option if you have a BRCA1, BRCA2, or PALB2 gene mutation and have not yet had treatment for your advanced disease.
Fountain Valley, CaliforniaAges 18 years+ - NCT06790693RecruitingPhase 3
Inavolisib plus hormone therapy for advanced breast cancer
This trial tests a new targeted therapy, inavolisib, combined with standard hormone therapy and a CDK4/6 inhibitor for people with a specific genetic mutation (PIK3CA) in their hormone receptor-positive, HER2-negative advanced breast cancer that has not been treated before. It compares this combination to a placebo plus the same standard treatments.
Burbank, CaliforniaAges 18 years+ - NCT05564377RecruitingPhase 2
Find targeted cancer treatments using genetic testing
This study matches people with advanced solid tumors to targeted treatment plans based on genetic testing. It also requires tumor sample testing to help doctors choose the most promising therapy for your specific tumor changes.
Arroyo Grande, CaliforniaAges Any age - NCT06369285RecruitingPhase 2
Alisertib and hormone therapy for advanced breast cancer
This trial tests a new drug, alisertib, combined with hormone therapy for people with HR-positive, HER2-negative breast cancer that has spread or come back and is no longer curable. It may be an option if you've already tried at least two hormone therapies and a CDK4/6 inhibitor.
Beverly Hills, CaliforniaAges 18 years+ - NCT04305834RecruitingPhase 2
Abemaciclib plus hormone pills for metastatic breast cancer in older adults
This Phase 2 study tests whether abemaciclib combined with standard hormone (endocrine) therapy can better control metastatic breast cancer in people age 70 and older. It may help if your cancer has already grown despite prior hormone therapy and/or other cancer medicines.
South Pasadena, CaliforniaAges 70 years+ - NCT04585750RecruitingPhase 1/Phase 2
Study drug for TP53 Y220C-mutated advanced cancers
This early-phase study tests PC14586 (rezatapopt) in people with advanced or metastatic solid cancers that carry a specific TP53 mutation called Y220C. It mainly looks at safety and how well the treatment may work, sometimes combined with pembrolizumab.
Irvine, CaliforniaAges 12 years+ - NCT05216432RecruitingPhase 1
RLY-2608 for PIK3CA-mutant advanced solid tumors and breast cancer
This early study (Phase 1) tests RLY-2608, a targeted cancer drug for tumors with a PIK3CA mutation. It studies the drug alone and combined with hormone therapy (and sometimes CDK4/6 or CDK4 medicines) to see safety, dose, and whether it can shrink tumors.
San Diego, CaliforniaAges 18 years+ - NCT05508906RecruitingPhase 1
Test drug OP-1250 with other medicines in ER-positive breast cancer
This Phase 1b study tests OP-1250 (palazestrant) combined with other targeted medicines for ER-positive, HER2-negative advanced or metastatic breast cancer. It mainly looks at safety and correct dosing, but may also help shrink tumors or slow growth.
San Francisco, CaliforniaAges 18 years+ - NCT05524584RecruitingPhase 2
Anastrozole, fulvestrant, and abemaciclib for hormone-positive breast cancer
This trial tests whether combining three medicines can better control hormone-receptor–positive, HER2-negative metastatic breast cancer that cannot be cured with surgery or radiation. It may help shrink tumors and slow disease growth compared with standard hormone therapy approaches.
Orange, CaliforniaAges 18 years+ - NCT05579366RecruitingPhase 1/Phase 2
Study drug for advanced ovarian and other solid cancers
This Phase 1/2 trial studies Rinatabart Sesutecan to treat advanced cancers, with special focus on certain ovarian cancer types. It’s meant for people whose cancer has come back or has not responded to prior treatments.
Los Angeles, CaliforniaAges 18 years+ - NCT06445738Recruiting
Can some women safely skip radiation after breast cancer surgery?
This trial is for women 50 and older with early-stage, hormone-positive or HER2-positive breast cancer. It tests whether it is safe to skip radiation therapy after a lumpectomy if an MRI before surgery shows the breast tissue looks a certain way.
San Francisco, CaliforniaAges 50 years+ - NCT06533826RecruitingPhase 2
Testing two antibody drugs for HER2-low breast cancer
This trial tests two antibody-drug conjugates (Enhertu and Datroway) for breast cancer that is HER2-low or HER2-0. It aims to find the best treatment sequence for people whose cancer has stopped responding to prior therapy.
San Francisco, CaliforniaAges 18 years+ - NCT06568692RecruitingPhase 2
Study of PCS6422 with capecitabine for advanced breast cancer
This trial tests a new drug combination (PCS6422 plus capecitabine) for people with advanced or metastatic breast cancer that has not responded to other treatments. The goal is to see if adding PCS6422 can make the chemotherapy work better.
Oxnard, CaliforniaAges 18 years+ - NCT06625775RecruitingPhase 1
Study of BBO-10203 for advanced solid tumors
This trial tests a new drug called BBO-10203, alone or combined with other cancer treatments, for people with certain advanced breast, colorectal, or lung cancers. It aims to see if the drug is safe and effective.
Los Angeles, CaliforniaAges 18 years+
HER2-negative Breast Cancer trials by city in California
Where these studies are running in California
Institutions with a site for the recruiting her2-negative breast cancer studies listed above.
- University of California, San Francisco · 7 studies
- City of Hope Comprehensive Cancer Center · 6 studies
- City of Hope Orange County Lennar Foundation Cancer Center · 6 studies
- Cedars-Sinai Medical Center · 5 studies
- Sutter Medical Center Sacramento · 5 studies
- University of California, Irvine Medical Center / UC Irvine Health · 5 studies
- University of California, Los Angeles (UCLA) · 5 studies
- Alta Bates Summit Medical Center · 4 studies
What taking part in a her2-negative 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.
HER2-negative Breast Cancer trials in other states
Common questions
- Are there her2-negative breast cancer clinical trials in California?
- Yes. We're currently tracking 37 recruiting her2-negative 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 her2-negative 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 her2-negative 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 her2-negative 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.