Testing new treatment with other drugs for advanced breast cancer

Recruting new patients

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    What is this study about?

    This study is exploring a new treatment for women with advanced breast cancer. It focuses on patients who have hormone receptor-positive, HER2-negative breast cancer and a specific genetic change (ESR1 mutation). About 300 women will participate. The study compares a new drug, AZD9833 in combination with a group of drugs called CDK4/6 inhibitors (palbociclib, abemaciclib, or ribociclib) with standard treatments (anastrozole or letrozole) in combination with CDK4/6 inhibitor. The aim is to see if AZD9833 works better than standard treatments in stopping cancer from growing.

    Learn more about this Trial

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      Where does the clinical trial take place?

      Graz , Austria

      Innsbruck , Austria

      Salzburg , Austria

      Wien , Austria

      Wien , Austria

      Leuven , Belgium

      Liu00e8ge , Belgium

      Namur , Belgium

      Haskovo , Bulgaria

      Panagyurishte , Bulgaria

      Pleven , Bulgaria

      Plovdiv , Bulgaria

      Sofia , Bulgaria

      Sofia , Bulgaria

      Sofia , Bulgaria

      Sofia , Bulgaria

      Sofia , Bulgaria

      Avignon Cedex 09 , France

      Brest , France

      Clermont-Ferrand , France

      Dijon , France

      Limoges , France

      Lorient cedex , France

      Lyon Cedex 08 , France

      Marseille , France

      Metz-Tessy , France

      Nimes , France

      Paris Cedex 5 , France

      Rouen , France

      Saint Herblain Cedex , France

      Saint-cloud , France

      Toulouse , France

      Tours , France

      Vandoeuvre les Nancy , France

      Vantoux , France

      Villejuif Cedex , France

      Ansbach , Germany

      Aschaffenburg , Germany

      Augsburg , Germany

      Bonn , Germany

      Chemnitz , Germany

      Dresden , Germany

      Erlangen , Germany

      Essen , Germany

      Freiburg , Germany

      Immenstadt , Germany

      Koblenz , Germany

      Leipzig , Germany

      Mannheim , Germany

      Mu00fcnchen , Germany

      Paderborn , Germany

      Ratingen , Germany

      Ravensburg , Germany

      Regensburg , Germany

      Stade , Germany

      Tu00fcbingen , Germany

      Ulm , Germany

      Budapest , Hungary

      Budapest , Hungary

      Miskolc , Hungary

      Szekszu00e1rd , Hungary

      Szolnok , Hungary

      Zalaegerszeg , Hungary

      Bergamo , Italy

      Bologna , Italy

      Firenze , Italy

      Meldola , Italy

      Milano , Italy

      Milan , Italy

      Misterbianco , Italy

      Napoli , Italy

      Padova , Italy

      Roma , Italy

      Rozzano , Italy

      Drammen , Norway

      Oslo , Norway

      Bydgoszcz , Poland

      Gdynia , Poland

      Koszalin , Poland

      Poznan , Poland

      Rzeszu00f3w , Poland

      Tomaszu00f3w Mazowiecki , Poland

      Warszawa , Poland

      u0141u00f3du017a , Poland

      Guimaru00e3es , Portugal

      Lisboa , Portugal

      Lisboa , Portugal

      Lisboa , Portugal

      Lisboa , Portugal

      Loures , Portugal

      Porto , Portugal

      Porto , Portugal

      Porto , Portugal

      Vila Nova de Gaia , Portugal

      Bansku00e1 Bystrica , Slovakia

      Bratislava , Slovakia

      Kosice , Slovakia

      Michalovce , Slovakia

      Partizanske , Slovakia

      Badalona , Spain

      Barcelona , Spain

      L’Hospitalet de Llobregat , Spain

      La Coruna , Spain

      Madrid , Spain

      Madrid , Spain

      Murcia , Spain

      Mu00e1laga , Spain

      Sant Joan Despi , Spain

      Sevilla , Spain

      Valencia , Spain

      Blackpool , United Kingdom

      Cambridge , United Kingdom

      London , United Kingdom

      London , United Kingdom

      Manchester , United Kingdom

      Nottingham , United Kingdom

      Portsmouth , United Kingdom

      Sheffield , United Kingdom

      Sutton , United Kingdom

      Taunton , United Kingdom

      Study Steps

      How Complex Will My Study Be and What Phases Will I Go Through?

      In this clinical trial, participants are required to follow these steps:

      1. Take their trial treatments over 28-day cycles. This involves taking a placebo and either AZD9833 or an aromatase inhibitor (AI) once daily by mouth for all 28 days.
      2. If taking abemaciclib, take it twice daily by mouth for all 28 days.
      3. If taking palbociclib or ribociclib, take it once daily by mouth for 21 days, then stop for the final 7 days of the cycle.
      4. Repeat the 28-day cycle receiving the trial treatment in the same way for as long as they are in the trial.
      5. Visit the trial site regularly throughout the trial. During these visits, trial doctors will check the health of the participants, take blood samples, and perform scans of the tumors.
      6. Continue taking the trial treatment until their cancer progresses or they decide to leave the trial.

      Diseases Under Investigation

      What Conditions Qualify Me for This Study?

      To join the study, you must have the following diseases:

      1. Advanced breast cancer that is not able to be treated with surgery or radiation.
      2. Breast cancer with an ESR1 mutation.
      3. Breast cancer that is hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative.

      Terms and conditions

      What Requirements I Have to Meet To Join This Study?

      When Am I Eligible to Join the Study?

      Below are the conditions you must meet to join the study along with explanations of medical terms where necessary:

      Inclusion Criteria:

      1. Advanced breast cancer: Your cancer cannot be treated with surgery or radiation.
      2. ESR1 mutation: This refers to a specific genetic change in the ESR1 gene that can affect how breast cancer grows.
      3. HR-positive and HER2-negative breast cancer: This means your cancer cells grow in response to hormones (HR-positive), but do not have a higher than normal amount of the HER2 protein on their surfaces (HER2-negative).
      4. On CDK4/6 inhibitor and AI treatment: You have been taking drugs called CDK4/6 inhibitors (e.g., palbociclib, abemaciclib, or ribociclib) and aromatase inhibitors (AI; e.g., letrozole or anastrozole) for at least 6 months.
      5. No cancer progression on AI and CDK4/6 inhibitor: Your cancer has not gotten worse after taking an AI and CDK4/6 inhibitor.
      6. Able to do daily activities: You do not have significant disability and can carry out everyday tasks.
      7. At least 18 years old.
      8. Proven diagnosis of adenocarcinoma of the breast: This is a type of breast cancer that originates in glandular tissue.
      9. Estrogen receptor positive (ER+)/HER2- breast cancer: Confirm this diagnosis through local laboratory results; this detail further specifies the type of breast cancer as explained in point 3.
      10. On specific AI + CDK4/6 inhibitor treatment: As mentioned in point 4, but also possibly taking LHRH (luteinizing hormone-releasing hormone) agonists as part of initial therapies for advanced disease.
      11. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1: This is a scale that assesses how your disease affects your daily living abilities. A score of 0 means you are able to carry out all normal activity without restriction. A score of 1 indicates you are restricted in physically strenuous activity but can walk and carry out light or sedentary work.
      12. ESR1 mutation detected by central testing: A central laboratory must verify the presence of the ESR1 mutation in your circulating tumor DNA (ctDNA).
      13. Willingness and ability to comply: You should be committed to and capable of attending the planned visits, adhering to the treatment plan, undergoing laboratory tests, and following other study procedures.
      14. Adequate organ and marrow function: Your organs must function well enough to tolerate the study treatments, and your bone marrow must be producing blood cells adequately.

      Please note that these criteria must be met without considering the exclusion criteria for the study.

      What Reasons Could Exclude Me from the Study?

      Here is a list of conditions that would exclude you from participating in the study along with explanations of medical terms where necessary:

      1. Advanced, symptomatic, visceral spread: If your cancer has spread extensively to internal organs and is causing symptoms, and there is a risk of life-threatening complications in the near future, you cannot participate.
      2. Known active uncontrolled or symptomatic CNS metastases: If the cancer has spread to your central nervous system (CNS), which includes the brain and spinal cord, and is not under control or causing symptoms, you are excluded from the study.
      3. Carcinomatous meningitis or leptomeningeal disease: If you have a condition where cancer cells have spread to the meninges (the protective membranes covering the brain and spinal cord), you cannot take part in the trial.
      4. Severe or uncontrolled systemic diseases: If you have serious or unchecked diseases that affect your whole body and, in the opinion of the investigator, could interfere with your participation in the study or adherence to the study protocol, you are excluded.
      5. Known or family history of severe heart disease: If you have, or there is a family history of significant heart problems, you cannot participate in the study.
      6. Previous treatment with AZD9833, investigational SERDs or fulvestrant: If you have previously been treated with the drug AZD9833, Selective Estrogen Receptor Degraders (SERDs), or the drug fulvestrant, you are excluded from the trial.
      7. Currently pregnant or breastfeeding: If you are pregnant, as confirmed by a positive pregnancy test, or if you are breastfeeding, you cannot take part in the study.

      Ensure you discuss any potential concerns with the clinical trial team or your healthcare provider to determine your eligibility.

      Investigational Medicinal Product

      What Products Are Being Used in This Study?

      The drugs involved in the study are:

      1. Letrozole: This is an aromatase inhibitor used in the treatment of hormonally-responsive breast cancer after surgery.
      2. Palbociclib: It is a selective inhibitor of the cyclin-dependent kinases CDK4 and CDK6 used in breast cancer therapy.
      3. Anastrozole: Similar to Letrozole, it is an aromatase inhibitor used in the treatment of breast cancer in post-menopausal women.
      4. Hormones (active substances may vary)
      5. Prolactin Release-Inhibiting Factors: These are substances that inhibit the release of prolactin, which has various roles including lactation postpartum.

      Please note that the term “Hormones” encompasses a wide range of active substances and the specific ones used in the study have not been listed. Therefore, no specific active substance can be provided for it.

      Have the Medicinal Substances Used in the Trial Been Previously Studied in Medicine?

      The clinical trial includes the following active substances:

      1. AZD9833: This substance is being used as a trial medication and is known as a next-generation oral Selective Estrogen Receptor Degrader (SERD). It is administered orally at a dose of 75 mg once daily.
      2. Anastrozole: Anastrozole is a well-known medication used in the treatment of breast cancer, particularly hormone receptor-positive breast cancer. It is used to reduce levels of estrogen in the body. Anastrozole tablets are administered orally in the trial.
      3. Letrozole: Letrozole is another medication regularly used for hormone receptor-positive breast cancer and serves a similar purpose as anastrozole, which is to decrease estrogen levels. Letrozole tablets are taken orally in the context of the trial.
      4. Palbociclib: Palbociclib is a medication approved for the treatment of specific types of advanced breast cancer. It is known as a cyclin-dependent kinase inhibitor, which works by slowing the growth of cancer cells. In the trial, palbociclib tablets/capsules are taken orally.
      5. Abemaciclib: This drug is also a cyclin-dependent kinase inhibitor like palbociclib, and it is used to treat certain types of breast cancer. Abemaciclib tablets are administered orally as part of the trial protocol.
      6. Ribociclib: Similar to palbociclib and abemaciclib, ribociclib is used to treat certain advanced or metastatic breast cancers, often in combination with other medications. Ribociclib tablets are given orally during the trial.

      All of the substances listed above are known to medicine and have been referenced in medical literature. They are being investigated in various combinations as part of the clinical trial.

      Study ID


      Recruitment status

      Recruting new patients

      Start of the trial

      3 years ago