Clinical Trials for Metastatic Breast Cancer
175 metastatic breast cancer trials indexed, 94 currently recruiting. Updated daily from ClinicalTrials.gov.
Understanding Metastatic Breast Cancer
Metastatic breast cancer is a stage of breast cancer where the disease has spread beyond the breast to other parts of the body. This spread often involves organs such as the bones, liver, lungs, or brain. The underlying biology involves cancer cells breaking away from the original tumor, traveling through the bloodstream or lymphatic system, and forming new tumors in distant tissues. Diagnosis typically involves imaging tests like CT scans, bone scans, or MRIs, alongside biopsies to confirm cancer cell presence in new sites. Blood tests may also support diagnosis by checking for tumor markers.
Common symptoms of metastatic breast cancer vary depending on where the cancer has spread. Bone metastases can cause pain or fractures, while lung involvement may lead to shortness of breath or coughing. Liver metastases might cause jaundice or abdominal swelling. The typical age of onset is usually in women over 50, but it can affect younger women as well. Risk factors include a history of early-stage breast cancer, certain genetic mutations such as BRCA1 or BRCA2, and hormone receptor status of the original tumor. Men can also develop metastatic breast cancer, though it is much rarer.
Metastatic breast cancer is a significant medical and social concern because it is the leading cause of breast cancer deaths. Approximately 20 to 30 percent of women with early-stage breast cancer eventually develop metastatic disease. It is estimated that about 168,000 women in the United States live with metastatic breast cancer at any given time. The economic burden is substantial, with treatments and supportive care costing billions annually. This stage of cancer requires ongoing management and affects patients’ quality of life and daily functioning.
The Metastatic Breast Cancer Treatment Landscape
The first-line treatment for metastatic breast cancer depends on factors like hormone receptor status and HER2 protein expression. For hormone receptor-positive cancers, endocrine therapies such as aromatase inhibitors or selective estrogen receptor modulators are commonly used. HER2-positive cancers are treated with targeted therapies like trastuzumab combined with chemotherapy. Treatment is often sequenced to balance effectiveness and side effects, starting with less aggressive options and moving to stronger therapies as needed. The goal is to control the cancer, relieve symptoms, and maintain quality of life.
Second- and third-line treatment options come into play when cancer progresses despite initial therapy. These options include chemotherapy drugs such as taxanes and anthracyclines. Targeted therapies like CDK4/6 inhibitors and PARP inhibitors may be used depending on the cancer’s genetic profile. Immunotherapy is also an option for certain patients, especially those with triple-negative breast cancer. The choice of treatment is personalized based on previous responses, side effects, and patient preferences.
Despite advances, there are still significant gaps in treatment for metastatic breast cancer. Some subgroups, like triple-negative breast cancer patients, often respond poorly to available therapies. Resistance to drugs develops over time, limiting long-term effectiveness. Side effects from treatments can be severe, affecting patients’ ability to continue therapy. Research is focused on overcoming resistance, finding treatments with fewer side effects, and developing therapies that target specific cancer mutations or the tumor microenvironment.
Why Clinical Trials Matter for Metastatic Breast Cancer
Clinical trials provide patients with access to new treatments that are not yet widely available. These trials can offer options when standard therapies have failed or are no longer effective. Participation also means closer medical monitoring and care from specialized teams. According to ClinicalTrials.gov, there are currently 175 metastatic breast cancer clinical trials indexed, with 94 actively recruiting patients. This shows the ongoing effort to find better ways to treat this condition.
Joining a clinical trial involves some risks. The effectiveness of the new treatment is not guaranteed, and some patients may receive a placebo or standard treatment instead of the experimental drug. Additional clinic visits and tests are often required, which can be time-consuming. Side effects may also be unknown or more severe than expected. Patients should discuss these factors carefully with their healthcare providers before enrolling.
Clinical trials are sponsored by a mix of academic institutions, pharmaceutical companies, and cooperative groups. Each sponsor plays a role in advancing research and ensuring rigorous study design. ClinicalTrials.gov serves as a public registry that helps patients and doctors find trials suited to their needs. It provides detailed information about ongoing studies, eligibility criteria, and locations, making it easier to explore available options for metastatic breast cancer treatment.
What to Look for in a Metastatic Breast Cancer Clinical Trial
Clinical trials are divided into phases 1 through 4. Phase 1 trials test a new treatment's safety and dosage in a small group of patients. Phase 2 trials focus on effectiveness and continue safety monitoring with more participants. Phase 3 trials compare the new treatment to the current standard to see which works better. Phase 4 trials take place after a treatment is approved, tracking long-term effects and safety. For metastatic breast cancer, the most common trial phase is Phase 2, with 55 trials. There are 54 Phase 1 trials, 25 Phase 3 trials, and 16 trials without a specified phase.
Inclusion criteria are the rules that decide who can join a trial. For metastatic breast cancer, participants often must be adults, usually 18 years or older. Trials may require specific prior treatments, such as chemotherapy or hormone therapy. Biomarkers like hormone receptor status or HER2 status are commonly used to select patients. The cancer stage must be metastatic, meaning it has spread beyond the breast. Some trials also require a certain disease duration or measurable tumor size to track treatment effects clearly.
Exclusion criteria are factors that prevent someone from joining a trial. These rules protect patient safety and ensure clear results. People with certain other illnesses, like heart or liver problems, may be excluded. Drug interactions are also a concern; patients taking certain medications might not qualify. Safety limits, such as low blood counts or organ function, are common reasons for exclusion. These criteria help researchers avoid risks and complications during the study.
Patients should consider practical factors before joining a trial. The length of the trial and how often visits occur can impact daily life. Some trials require frequent visits to the clinic, which may involve travel. Patients should ask the research team about the total time commitment and visit schedule. It is also important to ask about possible side effects, how the treatment is given, and what happens if the treatment does not work. Understanding these details helps patients make informed decisions about joining a trial.
Primary Sources and Further Reading
Finding reliable information about metastatic breast cancer and clinical trials is important for patients and caregivers. The following trusted sources offer detailed explanations, updates on research, and guidance on participating in clinical trials. These resources are useful for learning more about treatment options and clinical trial processes.
- National Cancer Institute: Metastatic Breast Cancer Research
- MedlinePlus: Breast Cancer
- ClinicalTrials.gov: Metastatic Breast Cancer Trials
- CDC: Breast Cancer
Latest Research and Emerging Treatments for Metastatic Breast Cancer (2026)
Metastatic breast cancer treatment continues to evolve with several Phase 3 trials exploring new drugs and combinations. One study (NCT06380751) is testing saruparib combined with camizestrant, comparing it to current standard therapies that include CDK4/6 inhibitors like abemaciclib, ribociclib, and palbociclib. Saruparib belongs to a class of drugs called PARP inhibitors, which work by blocking enzymes that help cancer cells repair their DNA. Camizestrant is an oral selective estrogen receptor degrader, which aims to reduce cancer growth driven by hormones. This trial focuses on patients with hormone receptor-positive, HER2-negative metastatic breast cancer who have specific genetic mutations.
Another important study (NCT06065748) is evaluating giredestrant, a selective estrogen receptor degrader, compared with fulvestrant, both combined with CDK4/6 inhibitors. CDK4/6 inhibitors help stop cancer cells from multiplying by blocking proteins involved in cell division. This trial targets patients whose cancer has become resistant to prior hormone therapies. Early data suggests that giredestrant might offer a different way to block estrogen receptors, potentially improving outcomes for some patients.
Research is also ongoing into adding capivasertib to standard treatments (NCT04862663). Capivasertib works by inhibiting a protein called AKT, which is part of a pathway that helps cancer cells survive and grow. Combining capivasertib with CDK4/6 inhibitors and fulvestrant may help delay disease progression in hormone receptor-positive, HER2-negative metastatic breast cancer. These new drugs for metastatic breast cancer reflect efforts to tailor treatments based on how cancer cells grow and resist therapy. For patients, these studies could mean more personalized options and better control of their disease in the near future.
Frequently asked questions about Metastatic Breast Cancer trials
How do I find Metastatic Breast Cancer clinical trials?
The authoritative source for Metastatic Breast Cancer clinical trials is ClinicalTrials.gov, maintained by the U.S. National Library of Medicine. 175 metastatic breast cancer studies are currently indexed. You can search by entering "metastatic breast cancer" as the condition, then filter by recruiting status, phase, and location. TrialsAlert scans ClinicalTrials.gov daily for new metastatic breast cancer trials and delivers a plain-language briefing every Friday explaining what changed.
What phase are most Metastatic Breast Cancer trials in?
Across the 175 metastatic breast cancer trials TrialsAlert indexes, the most common phase is Phase 2. Early-phase studies (Phase 1 and Phase 2) test safety and initial efficacy. Phase 3 trials compare a candidate treatment against the current standard of care in larger populations and generate the evidence regulators use to approve new therapies.
How many Metastatic Breast Cancer clinical trials are currently recruiting?
As of the latest scan, 94 metastatic breast cancer trials have a "Recruiting" status on ClinicalTrials.gov, out of 175 total indexed. The recruiting figure changes daily as studies open, fill enrollment, and close. TrialsAlert subscribers are notified when a new recruiting metastatic breast cancer trial matches their tracked condition.
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