CancerDrs

Breast Cancer clinical trials in California

97 actively recruiting breast cancer trials at 111 sites across California.

Data from ClinicalTrials.gov · last refreshed

Payments from drug makers to the doctors running these trials

For 2 of the trials on this page, the pharmaceutical company funding the trial also disclosed payments to the physicians leading it — public data from the federal CMS Open Payments database. Paying clinical-trial investigators for site work is expected and necessary for industry-funded trials; the scale and source are simply useful context when you're deciding whether to enroll. See the full breast cancer transparency page →

Phase 3 Recruiting Academic/Other

Evaluating the Addition of Adjuvant Chemotherapy to Ovarian Function Suppression Plus Endocrine Therapy in Premenopausal Patients With pN0-1, ER-Positive/HER2-Negative Breast Cancer and an Oncotype Recurrence Score Less Than or Equal to 25

This Phase III Trial will determine whether adjuvant chemotherapy (ACT) added to ovarian function suppression (OFS) plus endocrine therapy (ET) is superior to OFS plus ET in improving invasive breast cancer-free survival (IBCFS) among prem…

Sponsor: NRG Oncology
NCT ID: NCT05879926
Sites in California:
  • Kaiser Permanente-Anaheim — Anaheim, California
  • Kaiser Permanente-Deer Valley Medical Center — Antioch, California
  • Mission Hope Medical Oncology - Arroyo Grande — Arroyo Grande, California
  • PCR Oncology — Arroyo Grande, California
  • Sutter Auburn Faith Hospital — Auburn, California
Phase 3 Recruiting Network

Shorter Chemo-Immunotherapy Without Anthracycline Drugs for Early-Stage Triple Negative Breast Cancer

This phase III trial compares the effects of shorter chemotherapy (chemo)-immunotherapy without anthracyclines to usual chemo-immunotherapy for the treatment of early-stage triple negative breast cancer. Paclitaxel is in a class of medicat…

Sponsor: SWOG Cancer Research Network
NCT ID: NCT05929768
Sites in California:
  • Kaiser Permanente-Anaheim — Anaheim, California
  • Mission Hope Medical Oncology - Arroyo Grande — Arroyo Grande, California
  • PCR Oncology — Arroyo Grande, California
  • Sutter Auburn Faith Hospital — Auburn, California
  • Sutter Cancer Centers Radiation Oncology Services-Auburn — Auburn, California
Phase 3 Recruiting NIH

Adding an Immunotherapy Drug, MEDI4736 (Durvalumab), to the Usual Chemotherapy Treatment (Paclitaxel, Cyclophosphamide, and Doxorubicin) for Stage II-III Breast Cancer

This phase III trial compares the addition of an immunotherapy drug (durvalumab) to usual chemotherapy versus usual chemotherapy alone in treating patients with MammaPrint High 2 Risk (MP2) stage II-III hormone receptor positive, HER2 nega…

Sponsor: National Cancer Institute (NCI)
NCT ID: NCT06058377
Sites in California:
  • Sutter Auburn Faith Hospital — Auburn, California
  • AIS Cancer Center at San Joaquin Community Hospital — Bakersfield, California
  • Alta Bates Summit Medical Center-Herrick Campus — Berkeley, California
  • Tower Cancer Research Foundation — Beverly Hills, California
  • City of Hope Comprehensive Cancer Center — Duarte, California
Phase 3 Recruiting NIH

Testing Whether Hormone Therapy With Ribociclib is as Effective as Chemotherapy Followed by Hormone Therapy With Ribociclib for the Treatment of High Anatomic Stage Breast Cancer With Low Recurrence Risk, The RxFINE-Low Trial

This phase III trial compares standard of care hormone therapy plus ribociclib to chemotherapy followed by hormone therapy plus ribociclib for the treatment of patients with high anatomic stage breast cancer with low risk of the cancer ret…

Sponsor: National Cancer Institute (NCI)
NCT ID: NCT07391774
Sites in California:
  • Sutter Auburn Faith Hospital — Auburn, California
  • Alta Bates Summit Medical Center-Herrick Campus — Berkeley, California
  • Tower Cancer Research Foundation — Beverly Hills, California
  • UCI Health - Chao Family Comprehensive Cancer Center and Ambulatory Care — Irvine, California
  • Memorial Medical Center — Modesto, California
Phase 3 Recruiting Industry

Study of Sacituzumab Govitecan-hziy and Pembrolizumab Versus Treatment of Physician's Choice in Patients With Triple Negative Breast Cancer Who Have Residual Invasive Disease After Surgery and Neoadjuvant Therapy (ASCENT-05/AFT-65 OptimICE-RD/GBG 119/NSABP B-63)

The goal of this study is to find out if the experimental product, sacituzumab govitecan-hziy (SG) in combination with pembrolizumab given after surgery, is effective and safe compared to the treatment of physician's choice (TPC) which inc…

Sponsor: Gilead Sciences
NCT ID: NCT05633654
Sites in California:
  • Alta Bates Summit Medical Center — Berkeley, California
  • Community Cancer Institute — Clovis, California
  • PIH Health Whittier Hospital — Downey, California
  • Compassionate Cancer Care Medical Group - Inc — Fountain Valley, California
  • Los Angeles Cancer Network — Los Angeles, California
Phase 3 Recruiting Industry

A Study of Camizestrant in ER+/HER2- Early Breast Cancer After at Least 2 Years of Standard Adjuvant Endocrine Therapy

This is a Phase III open-label study to assess if camizestrant improves outcomes compared to standard endocrine therapy in patients with ER+/HER2 - early breast cancer with intermediate or high risk for disease recurrence who completed def…

Sponsor: AstraZeneca
NCT ID: NCT05774951
Sites in California:
  • Research Site — Anaheim, California
  • Research Site — Beverly Hills, California
  • Research Site — Concord, California
  • Research Site — Corona, California
  • Research Site — Fountain Valley, California
Phase 3 Recruiting Industry

A Study to Learn About the Study Medicine Called PF-07248144 in Combination With Fulvestrant in People With HR-positive, HER2-negative Advanced or Metastatic Breast Cancer Who Progressed After a Prior Line of Treatment.

The purpose of this study is to learn about the safety and effects of the study medicine PF-07248144 when given along with fulvestrant for the possible treatment of HR-positive, HER2-negative advanced or metastatic breast cancer. HR-positi…

Sponsor: Pfizer
NCT ID: NCT07062965
Sites in California:
  • Ventura County Hematology Oncology Specialists — Camarillo, California
  • Los Angeles Cancer Network - (Admin Only / Central IDS) - No Patients — Glendale, California
  • Los Angeles Cancer Network - Good Samaritan — Los Angeles, California
  • Los Angeles Hematology Oncology Medical Group — Los Angeles, California
  • Rolling Oaks Radiology - Oxnard — Oxnard, California
Phase 3 Recruiting Academic/Other

The CDK4/6 Inhibitor Dosing Knowledge (CDK) Study

The purpose of this study is to generate evidence on an alternative dosing strategy for CDK4/6 inhibitors to help more patients with Metastatic Breast Cancer (MBC) (age ≥ 60 years) tolerate side effects and stay on treatment longer, to der…

Sponsor: American Society of Clinical Oncology
NCT ID: NCT06377852
Sites in California:
  • Providence Medical Foundation — Eureka, California
  • Providence Medical Foundation — Santa Rosa, California
Phase 3 Recruiting Industry

Study of the Bria-IMT Regimen and CPI vs Physicians' Choice in Advanced Metastatic Breast Cancer.

This is a multicenter randomized, open label study to evaluate overall survival with the Bria-IMT regimen in combination with Checkpoint Inhibitor \[Retifanlimab\], versus Treatment of Patients'/Physicians' Choice (TPC) in advanced metasta…

Sponsor: BriaCell Therapeutics Corporation
NCT ID: NCT06072612
Sites in California:
  • Los Angeles cancer Network_Anaheim — Anaheim, California
  • Comprehensive Blood and Cancer Center — Bakersfield, California
  • Cedars-Sinai Cancer Beverly Hills — Beverly Hills, California
  • Los Angeles Cancer Network_Corona — Corona, California
  • Los Angeles cancer Network_Fountain Vallley — Fountain Valley, California
Phase 3 Recruiting Industry

ROSETTA Breast-01: The Effects and Safety of Pumitamig in Patients With Triple-Negative Breast Cancer

This is a Phase III trial where participants will be randomized to two treatment groups, which means participants will be assigned by equal chance to a treatment group. This trial will be double-blinded, which means neither the participant…

Sponsor: BioNTech SE
NCT ID: NCT07173751
Sites in California:
  • University Of California - San Diego Moores Cancer Center — La Jolla, California
  • Cancer and Blood Specialty Clinic (CBSC) — Los Alamitos, California
  • Cedar Sinai - Samuel Oschin Cancer Center — Los Angeles, California
  • Stanford University School of Medicine - Stanford Cancer Institute (SCI) - Stanford Women's Cancer Center — Palo Alto, California
  • University Of California Davis Health System — Sacramento, California
Phase 3 Recruiting Industry

A Phase III Study of Dato-DXd With or Without Durvalumab Compared With Investigator's Choice of Chemotherapy in Combination With Pembrolizumab in Patients With PD-L1 Positive Locally Recurrent Inoperable or Metastatic Triple-negative Breast Cancer (TROPION-Breast05)

This is a Phase III, randomised, open-label, 3-arm, multicentre, international study assessing the efficacy and safety of Dato-DXd with or without durvalumab compared with investigator's choice chemotherapy in combination with pembrolizuma…

Sponsor: AstraZeneca
NCT ID: NCT06103864
Sites in California:
  • Research Site — Duarte, California
  • Research Site — Fountain Valley, California
  • Research Site — Glendale, California
  • Research Site — Sacramento, California
  • Research Site — Santa Rosa, California
Phase 3 Recruiting Industry

A Clinical Study of Sacituzumab Tirumotecan (Sac-TMT, MK-2870) in People With Breast Cancer (MK-2870-032)

Researchers are looking for new ways to treat types of breast cancer that are both: * High-risk, which means the cancer may have a higher chance of getting worse or coming back after treatment * Early-stage, which means the cancer is in th…

Sponsor: Merck Sharp & Dohme LLC
NCT ID: NCT06966700
Sites in California:
  • Roy and Patricia Disney Family Cancer Center ( Site 0055) — Burbank, California
  • Community Cancer Institute ( Site 0100) — Clovis, California
  • Providence Medical Foundation ( Site 0080) — Fullerton, California
  • MemorialCare Health System - Long Beach Medical Center ( Site 9556) — Long Beach, California
  • El Camino Hospital Cancer Center ( Site 0096) — Mountain View, California
Phase 3 Recruiting Industry

A Study Evaluating the Efficacy and Safety of Inavolisib Plus CDK4/6 Inhibitor and Letrozole vs Placebo + CDK4/6i and Letrozole in Participants With Endocrine-Sensitive PIK3CA-Mutated, Hormone Receptor-Positive, HER2-Negative Advanced Breast Cancer

This study will evaluate the efficacy and safety of the combination of inavolisib plus a cyclin-dependent kinase 4 and 6 inhibitor (CDK4/6i) and letrozole versus placebo plus a CDK4/6i and letrozole in the first-line setting in participant…

Sponsor: Hoffmann-La Roche
NCT ID: NCT06790693
Sites in California:
  • Disney Family Cancer Center — Burbank, California
  • City of Hope - Lennar Foundation Cancer Center — Irvine, California
  • Scripps Health — La Jolla, California
  • City Of Hope — Long Beach, California
  • Cancer and Blood Specialty Clinic — Los Alamitos, California
Phase 3 Recruiting Industry

Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer

This phase 3 clinical trial compares the efficacy and safety of palazestrant with ribociclib to letrozole and ribociclib in women and men who have not received prior systemic anti-cancer treatment for advanced breast cancer.

Sponsor: Olema Pharmaceuticals, Inc.
NCT ID: NCT07085767
Sites in California:
  • Clinical Trial Site — Beverly Hills, California
  • Clinical Trial Site — La Jolla, California
  • Clinical Trial Site — Los Alamitos, California
  • Clinical Trial Site — Oakland, California
  • Clinical Trial Site — Roseville, California
Phase 3 Recruiting Industry

Saruparib (AZD5305) Plus Camizestrant or Plus Endocrine Therapy, Compared With CDK4/6 Inhibitor Plus Endocrine Therapy or Plus Camizestrant in HR-Positive, HER2-Negative (IHC 0, 1+, 2+/ ISH Non-amplified), BRCA1, BRCA2, or PALB2m Advanced Breast Cancer

The primary objective of the study is to measure efficacy of saruparib (AZD5305) plus camizestrant compared with physician's choice CDK4/6i plus ET in patients with BRCA1, BRCA2, or PALB2m, HR-positive, HER2-negative (defined as IHC 0, 1+,…

Sponsor: AstraZeneca
NCT ID: NCT06380751
Sites in California:
  • Research Site — Fountain Valley, California
  • Research Site — Glendale, California
  • Research Site — Los Angeles, California
  • Research Site — Newport Beach, California
Phase 3 Recruiting Industry

Phase 3 Study of RLY-2608 + Fulvestrant vs Capivasertib + Fulvestrant as Treatment for Locally Advanced or Metastatic PIK3CA-mutant HR+/HER2- Breast Cancer

This is a global, multicenter, open-label, randomized Phase 3 study comparing the efficacy and safety of RLY-2608 (zovegalisib) + fulvestrant to capivasertib + fulvestrant for the treatment of patients with HR+/HER2- ABC with PIK3CA mutati…

Sponsor: Relay Therapeutics, Inc.
NCT ID: NCT06982521
Sites in California:
  • Beverly Hills Cancer Center — Beverly Hills, California
  • City of Hope National Medical Center — Duarte, California
  • Cedars-Sinai Medical Center — Los Angeles, California
  • Stanford Women's Cancer Center — Palo Alto, California
  • University of California, Davis Comprehensive Cancer Center — Sacramento, California
Phase 3 Recruiting Industry

Phase 3 Study to Evaluate the Efficacy and Safety of HER2/Neu Peptide GLSI-100 (GP2 + GM-CSF) in HER2/Neu Positive Subjects

This is a prospective, randomized, double-blinded, placebo-controlled, multi-center, Phase 3 study of GLSI-100 immunotherapy in HLA-A\*02 positive and HER2/neu positive subjects who are at high risk for disease recurrence and have complete…

Sponsor: Greenwich LifeSciences, Inc.
NCT ID: NCT05232916
Sites in California:
  • City of Hope - Duarte Cancer Center — Duarte, California
  • Providence St. Jude Medical Center - Virginia K. Crosson Cancer Center — Fullerton, California
  • City of Hope - Orange County Lennar Foundation Cancer Center — Irvine, California
  • University of California San Diego - Moores Cancer Center — La Jolla, California
  • University of Southern California - Norris Comprehensive Cancer Center — Los Angeles, California
Phase 3 Recruiting Industry

A Study Comparing the Efficacy and Safety of Zanidatamab to Trastuzumab, Each in Combination With Physician's Choice Chemotherapy, for the Treatment of Participants With Metastatic HER2-positive Breast Cancer

The efficacy and safety of zanidatamab in combination with physician's choice of chemotherapy compared with trastuzumab in combination with physician's choice of chemotherapy will be evaluated for the treatment of participants with metasta…

Sponsor: Jazz Pharmaceuticals
NCT ID: NCT06435429
Sites in California:
  • The Oncology Institute Of Hope And Innovation — Cerritos, California
  • Los Angeles Hematology Oncology Medical Group Glendale — Glendale, California
  • USC-Norris Comprehensive Cancer Center - Investigational Drug Service IDS — Los Angeles, California
  • UCSF at Mission Bay MB — San Francisco, California
Phase 3 Recruiting Industry

A Study of Sacituzumab Tirumotecan (MK-2870) as a Single Agent and in Combination With Pembrolizumab (MK-3475) Versus Treatment of Physician's Choice in Participants With HR+/HER2- Unresectable Locally Advanced or Metastatic Breast Cancer (MK-2870-010)

The purpose of this study is to compare sacituzumab tirumotecan as a single agent, and in combination with pembrolizumab, versus Treatment of Physician's Choice (TPC) in participants with hormone receptor positive/human epidermal growth fa…

Sponsor: Merck Sharp & Dohme LLC
NCT ID: NCT06312176
Sites in California:
  • Providence Medical Foundation-Oncology ( Site 0020) — Fullerton, California
  • Moores Cancer Center ( Site 0059) — La Jolla, California
  • Cancer and Blood Specialty Clinic ( Site 0001) — Los Alamitos, California
Phase 2, Phase 3 Recruiting Industry

A Study of Izalontamab Brengitecan Versus Chemotherapy in Participants With Previously Untreated, Locally Advanced, Recurrent Inoperable, or Metastatic Triple-negative Breast Cancer Ineligible for Anti-PD(L)1 Drugs (IZABRIGHT-Breast01)

The purpose of this study is to assess the efficacy and safety of iza-bren, a bi-specific antibody-drug conjugate against EGFR and HER3 with a topoisomerase inhibitor payload versus treatment of physician's choice (TPC) (paclitaxel, nab-pa…

Sponsor: Bristol-Myers Squibb
NCT ID: NCT06926868
Sites in California:
  • Helios Clinical Research — Cerritos, California
  • Local Institution - 0307 — Cerritos, California
  • Local Institution - 0308 — Cerritos, California
  • Local Institution - 0309 — Cerritos, California
  • Local Institution - 0311 — Long Beach, California
Phase 3 Recruiting Industry

Evaluation of Lasofoxifene Combined With Abemaciclib Compared With Fulvestrant Combined With Abemaciclib in Locally Advanced or Metastatic ER+/HER2- Breast Cancer With an ESR1 Mutation

The goal of this clinical trial is to assess the efficacy, safety and tolerability of the combination of lasofoxifene and abemaciclib compared to fulvestrant and abemaciclib for the treatment of pre- and postmenopausal women and men who ha…

Sponsor: LeonaBio
NCT ID: NCT05696626
Sites in California:
  • Providence Medical Foundation - Santa Rosa, CA — Santa Rosa, California
Phase 3 Recruiting Industry

A Clinical Study of Patritumab Deruxtecan to Treat Breast Cancer (MK-1022-016)

Researchers are looking for other ways to treat breast cancer (BC) that is hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2-) and either unresectable locally advanced or metastatic. * HR positive (H…

Sponsor: Merck Sharp & Dohme LLC
NCT ID: NCT07060807
Sites in California:
  • Los Angeles Hematology Oncology Medical Group ( Site 0026) — Los Angeles, California
  • Hoag Memorial Hospital Presbyterian ( Site 0025) — Newport Beach, California
Phase 3 Recruiting Industry

Phase 3 Study of Gedatolisib as First-Line Treatment for Patients With HR-Positive, HER2-Negative Advanced Breast Cancer (VIKTORIA-2)

This is a Phase 3, open-label, randomized, clinical trial evaluating the efficacy and safety of gedatolisib and palbociclib plus endocrine therapy for the treatment of patients with locally advanced or metastatic HR+/HER2- advanced breast …

Sponsor: Celcuity Inc
NCT ID: NCT06757634
Sites in California:
  • City of Hope Medical Center — Duarte, California
  • Providence Medical Foundation — Fullerton, California
  • UCLA Hematology Oncology Santa Monica — Los Angeles, California
  • Cancer Care Associates — Redondo Beach, California
  • UC San Diego Moores Cancer Center — San Diego, California
Phase 2, Phase 3 Recruiting Industry

RO7771950 Versus Tucatinib in Combination With Trastuzumab and Capecitabine in People With Locally Advanced or Metastatic Breast Cancer That is Human Epidermal Growth Factor Receptor 2 (HER2)-Positive

The purpose of this study is to assess the efficacy and safety of RO7771950 in combination with trastuzumab and capecitabine, compared to tucatinib in combination with trastuzumab and capecitabine.

Sponsor: Hoffmann-La Roche
NCT ID: NCT07413939
Sites in California:
  • UCSF Helen Diller Family CCC — San Francisco, California
Phase 3 Recruiting Academic/Other

Fertility Preservation Using Tamoxifen and Letrozole in Estrogen Sensitive Tumors Trial

Latrogenic infertility as a result of cancer treatment has a profound effect on long-term quality of life in survivors of reproductive-age cancers. Oocyte cryopreservation prior to cancer treatment has been associated with improved quality…

Sponsor: University of California, San Francisco
NCT ID: NCT03011684
Sites in California:
  • University of California at San Francisco — San Francisco, California

Showing 25 of 97 trials with sites in California. See all breast cancer trials →

Medical disclaimer: This page aggregates public ClinicalTrials.gov data. It is not medical advice. Always confirm eligibility and enrollment details with the trial site or your oncologist.

Source: ClinicalTrials.gov API v2 · Last checked: 2026-10-12