A trial of abiraterone acetate (CB7630) for breast cancer that has spread

Please note - this trial is no longer recruiting patients. We hope to add results when they are available.

Cancer type:

Breast cancer



This trial is looking at abiraterone acetate for breast cancer that is locally advanced or has spread to another part of the body and is either oestrogen receptor positive or androgen receptor positive. This trial is supported by Cancer Research UK.

Doctors often use hormone therapy to treat breast cancer. It works best for women who have oestrogen receptor positive breast cancer (ER positive). This means there are receptors on the surface of the cancer cells that are triggered by the female hormone oestrogen. It locks onto the oestrogen receptors and stimulates the cancer to grow. Androgen receptors are similar, but triggered by hormones called androgens. Researchers think that some breast cancer cells may also have androgen receptors. They call this AR positive breast cancer.

Abiraterone (also called abiraterone acetate or CB7630) is a new drug. It stops the body making androgens and oestrogen. It has already been looked at in trials for men with prostate cancer that is no longer responding to hormone therapy. In this trial, the researchers want to see if it helps women with breast cancer that does not respond to standard treatments or has become resistant Open a glossary item to them.

The aims of the trial are to find out

  • The best dose of abiraterone to give
  • What happens to abiraterone in the body
  • How well it works for breast cancer
  • What the side effects are

Who can enter

You can enter this trial if

  • You have breast cancer that is locally advanced and cannot be removed with surgery or breast cancer that has spread to other parts of the body (metastatic)
  • Your cancer is growing
  • Tests show that there are oestrogen receptors or androgen receptors on the surface of your breast cancer cells
  • You are at least 45 and have not had periods for a year or more, or you are any age over 18 and have had both your ovaries surgically removed
  • You are well enough to take part in the trial (performance status 0, 1 or 2)
  • You have satisfactory blood test results

You cannot enter this trial if you

  • Have breast cancer that has no hormone receptors for oestrogen or androgens (it is hormone receptor negative)
  • Have cancer that has spread to your brain or spinal cord (central nervous system)
  • Have had radiotherapy for breast cancer in the last 4 weeks, apart from radiotherapy to control symptoms (palliative radiotherapy)
  • Have had any hormone therapy, immunotherapy Open a glossary item or chemotherapy in the last 4 weeks (or 6 weeks if you have had a drug called mitomycin C or one of a group of drugs called nitrosureas)
  • Have had another experimental drug in the last 4 weeks as part of a clinical trial
  • Still have bad side effects from any other treatment
  • Have another type of cancer apart from non melanoma skin cancer or carcinoma in situ of the cervix that has been successfully treated with surgery, or any other cancer that has been in complete remission Open a glossary item for at least 5 years
  • Have had major surgery or a serious injury in the last 4 weeks
  • Have high blood pressure that cannot be controlled with medicine
  • Have heart problems that are a cause for concern
  • Have problems with your adrenal gland Open a glossary item
  • Have problems with your pituitary gland Open a glossary item
  • Have any condition that could make it difficult for you to swallow or absorb abiraterone capsules
  • Have an autoimmune disease Open a glossary item that may need treatment with steroids
  • Have had a blood clot in the last year or have any other medical condition that could affect you taking part in the trial
  • Are known to be HIV positive or have a weakened immune system

Trial design

The trial will recruit up to 74 people in London. The trial is in 2 parts. In phase 1, the researchers want to find the best dose of abiraterone. The first 6 people taking part will have the lowest dose of abiraterone. If they don’t have any serious side effects, the next patients will have a higher dose. The trial team will increase the dose up to 3 times, until they find the best dose to give. This is called a dose escalation study.

In phase 2, the researchers will be looking at how well abiraterone works for advanced breast cancer.

Everybody taking part will take abiraterone capsules for between 1 and 12 months. The length of time you take the capsules for depends on whether or not they help you. You take them every day, an hour before breakfast.

As part of the trial, the researchers will take an extra blood sample to study your genes. They want to learn more about how genes affect the way people respond to abiraterone. The samples will be stored safely and used only for research purposes.

They may also ask your permission to take extra tissue samples (biopsies Open a glossary item) from your tumour

  • Before you start the trial treatment
  • After 2 weeks of treatment
  • At the end of the trial

This is so they can learn more about how the drugs affect breast cancer cells. If you agree to this, your doctor will explain more about how they will take the biopsies. If you do not want to have these extra biopsies done, you don’t have to. You can still take part in the trial.

Hospital visits

Before you take part in this trial, a doctor will examine you and you will have some tests. The tests include

  • Physical examination
  • Blood tests
  • Urine tests
  • Chest X-ray
  • Heart trace (ECG Open a glossary item)
  • CT scan
  • Bone scan
  • A heart scan called a MUGA scan Open a glossary item

You will have to go to hospital to take your capsules for the first 2 days of treatment. After that, you can take them at home.

You see the trial doctors and have blood tests every week for the first 2 months, then every 2 weeks for as long as you take abiraterone. You have a CT scan every 2 months.

If you take part in phase 1 of the trial, you will have some extra blood tests on the first 2 days you take the capsules.

After you finish treatment you will see the trial doctors, have blood tests and a CT scan 4 weeks later. If you have side effects from the trial drug, you will continue to have follow up appointments until they get better.

Side effects

Abiraterone acetate is a new drug and there may be some side effects that doctors don’t know about yet. In trials so far, the most common side effects were

  • Tiredness
  • A rise in blood pressure
  • A low level of potassium in the blood
  • Poor appetite
  • Fluid retention

If you do have side effects, your doctor may give you a steroid drug called hydrocortisone, or another type of drug called eplerenone to help.

Recruitment start:

Recruitment end:

How to join a clinical trial

Please note: In order to join a trial you will need to discuss it with your doctor, unless otherwise specified.

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Chief Investigator

Prof Johann de Bono

Supported by

Cancer Research UK (Centre for Drug Development)
Cougar Biotechnology
Experimental Cancer Medicine Centre (ECMC)
National Institute for Health Research Cancer Research Network (NCRN)

Other information

This is Cancer Research UK trial number CRUKD/08/044.

Contact our cancer information nurses for other questions about cancer by:

Phone - 0808 800 4040

Last review date

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Harriet wanted to try new treatments

Picture of Harriet

“I was keen to go on a clinical trial. I wanted to try new cancer treatments and hopefully help future generations.”

Last reviewed:

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