The study medicine, ARV-471 (also known as vepdegestrant), is a type of medicine called a PROTAC protein degrader. It is believed to work by targeting and degrading the estrogen receptor that is found in breast cancer cells. This prevents estrogen from connecting to the cancer cells which may block estrogen’s effects of helping the cancer cells grow. ARV-471 is taken by mouth once a day at the same time in the morning with food.
The TACTIVE-U clinical trial is researching how a study medicine, ARV-471 (also known as vepdegestrant), works and its safety when given with other breast cancer medicines in people with ER-positive, HER2-negative advanced or metastatic breast cancer.
As you explore possible next steps in your breast cancer treatment journey, we invite you to consider TACTIVE-U as a treatment option and appreciate your taking the time to learn more. Participants in TACTIVE-U will receive care from a dedicated team of healthcare providers who are seeking the next breakthrough in breast cancer treatment for people with advanced or metastatic breast cancer worldwide.
Who may participate
Thank you for considering the TACTIVE-U clinical trial. TACTIVE-U may be an option for you, if you:
Are 18 years old or older and have been diagnosed with advanced or metastatic breast cancer that
- Expresses estrogen receptors and is called ER-positive
- Does not express a marker, human epidermal growth factor receptor 2 (HER2) and is called HER2-negative
- Cannot be fully treated by surgery or radiation therapy
Has been treated with at least 1 prior round of treatment and no more than 2 prior rounds of treatment for advanced or metastatic disease.
- One (and only 1) of these rounds of treatment must have included a CDK4/6 inhibitor (e.g., KISQALI® (ribociclib), Verzenio® (abemaciclib), IBRANCE® (palbociclib))
- Is no longer responding to previous treatments
Other criteria may apply, which the study team will discuss with you.
If you don’t meet the requirements for this study, click here to learn more about other Pfizer breast cancer research opportunities.
Condition
ER-positive, HER2-negative locoregionally advanced or metastatic breast cancer
Age
18+ years
Sex
Male or Female
Each clinical study has its own guidelines for who can participate, called eligibility criteria. However, only the research study staff can determine if you qualify to enroll in the study.
Additional eligibility criteria
* Other eligibility criteria apply.
* Other eligibility criteria apply.
What to expect
TACTIVE-U is an “umbrella trial.” Umbrella clinical trials consist of smaller sub-studies, each testing different study medicine combinations in adults with advanced or metastatic ER-positive, HER2-negative breast cancer.
- TACTIVE-U Sub-study B will help us learn if ARV-471 is safe and effective when taken with the approved breast cancer medicine ribociclib (a CDK4/6 inhibitor)
- TACTIVE-U Sub-study C will help us learn if ARV-471 is safe and effective when taken with another study medicine, samuraciclib (a CDK7 inhibitor)
If you have met all eligibility criteria and agree to participate, you will take part in one of these sub-studies.
You will be given the study medicine (ARV-471) and another medicine as described above for you to take by mouth at home. There is no placebo given in TACTIVE-U and its sub-studies.
Length of study treatment
The time you can expect to be in the clinical trial depends upon a few things, including how you tolerate the study medicine, how your cancer responds, and your personal choice
Number of study visits
Varies – about once every 4 weeks once treatment underway, but more frequently when beginning treatment
Long-term follow up
You will be asked to attend a visit about a month after your last dose of the study medicine. You also may be contacted every 3 months to check on your health
About the study medicine
About the study medicine
Be Represented
Be Represented
Many factors, including genetics, race, ethnicity, and gender, can impact how people respond to a medicine. That is why it is so important that TACTIVE-U and each of its sub-studies include people of all backgrounds. The greater the diversity among clinical trial participants, the more we can learn about potential medicines, including how they work for different people.
By participating in TACTIVE-U, you are representing your community and could potentially help in the discovery of a treatment to help advanced or metastatic breast cancer patients around the world.
Frequently asked questions
Where can I find more information about this clinical trial?
Details about the study medicine and other treatments provided in the TACTIVE-U sub-studies will be answered during the informed consent process.
Will I receive active medicine?
Yes. All participants will receive active medicine. There is no placebo in this study.
What are the treatments in TACTIVE-U and how do they work?
The study medicine, ARV-471 (also known as vepdegestrant), is a type of medicine called a PROTAC protein degrader. It is designed to specifically target and destroy the estrogen receptor expressed by the breast cancer tumor cells. This prevents estrogen from connecting to the cancer cells which may block estrogen’s effects helping the cancer cells grow.
Ribociclib (given with ARV-471 in Sub-study B) is a CDK4/6 inhibitor that is approved for the treatment of ER-positive, HER2-negative advanced or metastatic breast cancer. CDK4/6 inhibitors are a type of medicine that block two proteins (CDK4 and CDK6) linked to the growth of ER-positive, HER2-negative advanced or metastatic breast cancer cells.
Samuraciclib (given with ARV-471 in Sub-study C) is a type of medicine called a CDK7 inhibitor, which blocks a protein (CDK7) linked to the growth of certain breast cancers. Samuraciclib is being studied for the treatment breast cancer.
Will I know which treatments I will receive?
Participants will know the sub-study they are taking part in, as well as the medicines and the doses of the medicines they are receiving. Medicine doses may vary across participants in order to find the best dosing options for treating advanced or metastatic breast cancer.
How should I take the treatments I receive in TACTIVE-U?
ARV-471 (also known as vepdegestrant) is taken by mouth once a day at the same time in the morning with food and should be taken prior to other study medicines.
Ribociclib (Sub-study B) is by mouth once a day taken with or without food. It is taken consecutively for 21 days followed by 7 days off treatment.
Samuraciclib (Sub-study C) is taken anytime during the day with or without food.
Do I need to provide tumor samples during the clinical trial?
You will be asked to provide a sample of your tumor from time of diagnosis or at the time of reappearance of your tumor locally or spread to your body after a period of improvement.
There will be an optional (not required) biopsy collected at the end of treatment if you have stopped the treatment because your cancer gets worse, if your study doctor considers the procedure safe for you, and if you agree to provide separate consent for this procedure.
The biopsy can be done with a needle or through a minor surgery, and it is usually done with local anesthesia (shots to numb the skin). You may or may not also receive sedation (medicines to help you be calm and comfortable). The study doctor will discuss with you the safest method and location to perform the biopsy.
How often do you assess my tumor?
Your tumor will be assessed every 8 weeks during the first year, and then every 12 weeks thereafter. This includes scans and measurement of skin lesions. Bone scans will be carried out every 24 weeks, if needed.
How long do study visits last?
Most study visits last for about 1-2 hours. There are some longer visits which will last about 5-6 hours, and a few visits for up to 8 hours. You will be given information in advance on which study visit will take longer.
Will I be reimbursed for clinical trial-related cost?
You may be reimbursed for any reasonable expenses that you may have as a result of taking part in this clinical trial. This may include parking, meals, or other travel-related expenses.
