A trial of BKM120 for advanced breast cancer that is hormone receptor positive and HER2 negative (BELLE 2)

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

Cancer type:

Breast cancer




Phase 3

This trial is looking at a drug called BKM120 for breast cancer that has spread into tissue surrounding the breast or to another part of your body and has got worse despite having a hormone therapy drug called an aromatase inhibitor Open a glossary item.

Breast cancer cells often have receptors for the hormones oestrogen or progesterone, or for a protein called HER2.

If there are a large number of hormone receptors, the cancer is called hormone receptor positive. In post menopausal Open a glossary item women, doctors can treat hormone receptor positive breast cancer with drugs called aromatase inhibitors. But breast cancer may stop responding to this type of treatment. If this happens, you may have another type of hormone therapy. Fulvestrant is a drug doctors can use.

If there are only small numbers of receptors for the HER2 protein, the cancer is called HER2 negative. HER2 negative breast cancer is unlikely to respond to drugs such as Herceptin and researchers are looking for new treatments to help women with this type of breast cancer.

In this trial, they are looking at a drug called BKM120 which is a type of biological therapy.  It is a cancer growth blocker.

The women taking part in this trial have breast cancer that is hormone receptor positive, HER2 negative, has spread into surrounding tissue or to a another part of the body, and has got worse despite having an aromatase inhibitor.

The aim of the trial is to see if BKM120 and fulvestrant is better than fulvestrant alone for this group of women.

Who can enter

You may be able to enter this trial if

  • You are a woman who has breast cancer that has spread into tissue surrounding your breast (locally advanced) and can’t be removed with surgery, or has spread to another part of your body
  • Your cancer is hormone receptor positive and HER2 negative
  • Your doctors can see that your cancer has come back or got worse since the last treatment you had
  • Your cancer came back or got worse while taking an aromatase inhibitor (AI) Open a glossary item– if you took an AI after surgery to remove early stage breast cancer, the cancer must have come back within a year of finishing it - if you took an AI as treatment for advanced cancer, the cancer must have started to get worse within a month of finishing
  • You have been through the menopause Open a glossary item
  • You are able to swallow medication
  • You have satisfactory blood test results
  • You are well enough to be up and about for at least half the day (performance status 0, 1 or 2)
  • You are at least 18 years old

You cannot enter this trial if you

  • Have cancer that has spread to your brain or spinal cord and is causing symptoms – you can take part if cancer spread to your brain was treated at least 4 weeks ago and is not causing symptoms
  • Are currently having any other cancer treatment, including experimental drugs
  • Have already had fulvestrant or drugs that target proteins called PI3K, AKT and mTOR – your doctor can advise you about this
  • Have had surgery in the last 2 weeks, or have not fully recovered from earlier surgery
  • Have had more than 1 type of chemotherapy for breast cancer that has spread that was stopped because your cancer got worse – this includes chemotherapy before or after surgery if your cancer got worse or came back while having the treatment or within 6 months of finishing it (12 months if the chemotherapy included a taxane drug Open a glossary item)
  • Have not recovered from the side effects of earlier treatment unless they are very mild (apart from hair loss)
  • Have had radiotherapy in the last 4 weeks (in the last 2 weeks if it was radiotherapy for symptoms given only to a small area of your body), or you haven’t fully recovered from the side effects of earlier radiotherapy treatment
  • Have had any other cancer in the last 3 years apart from non melanoma skin cancer or cervical cancer that was successfully treated
  • Take steroids Open a glossary item or any other medication that can damp down your immune system (steroid creams, eye drops and inhalers are allowed)
  • Take medication that can effect body substances called cytochrome P (CYP) enzymes – it is important that you don’t stop any medication without talking to your doctor
  • Have had mental health problems in the past, or have moderate to severe depression or severe anxiety– doctors use questionnaires to assess this
  • Have had a heart attack in the last 6 months, have certain other heart problems, or take medication that can affect your heart – the trial doctors can advise you about this
  • Have problems with your digestive system Open a glossary item that could affect how you absorb drugs
  • Are known to be very sensitive to anything in fulvestrant or BKM120
  • Have any other medical condition that the trial team think could affect you taking part
  • Are known to be HIV positive

Trial design

This phase 3 trial will recruit about 1,060 women around the world. Half the women taking part have fulvestrant and BKM120. The other half have fulvestrant and a dummy drug (placebo Open a glossary item).

The trial team need to get a sample of your tumour to look for changes to the cells (biomarkers Open a glossary item). If they can get a sample of tissue that was removed when you had surgery or a biopsy Open a glossary item in the past they will test this. But if there is not a sample available, they will ask you to have a new biopsy. You can’t take part in the trial if the team can’t get a sample of your breast cancer.

You have your first dose of fulvestrant while your tumour sample is being tested. You have fulvestrant as two injections - one into each buttock.

You are then put into 1 of 2 treatment group by a computer. This is called randomisation. Neither you nor your doctor will be able to decide which group you are in.  And neither of you will know which group you are in. This is called a double blind trial.

BELLE 2 trial diagram

You have 3 lots of fulvestrant injections 2 weeks apart, then you have them every 4 weeks after that. BKM120 (or the dummy drug) are capsules that you swallow each day.  You start taking the capsules when you have your second lot of injections.

As long as you don’t have bad side effects, you can carry on having treatment for as long as it helps you.

The trial team will ask you to fill out some questionnaires

  • Before you start treatment
  • 6 times in the first  3 months of treatment
  • Once every 4 weeks after that
  • When you finish treatment

Some of the questionnaires will ask about your mood and whether you feel depressed. Others will ask how anxious you are feeling.

Hospital visits

You see the trial team and have some tests before you start treatment. The tests include

If you have any cancer on your skin, your trial doctor may take a photograph. This will only show the cancer and the surrounding area. Your face will not be in the photograph and it will not be possible to identify you.

You see the trial team and have your first fulvestrant injections. Two weeks later, you start taking BKM120 (or the dummy drug). You go to hospital every week for the next 6 weeks, twice in the following 4 weeks and then once then every 4 weeks after that.

You have blood tests at each visit. You have a heart trace every 4 weeks and a heart scan every 4 months. You have a CT or MRI scan every 8 weeks during treatment.

When you finish treatment, you see the trial team within a week of the day you stop taking the capsules. You have a physical examination, blood tests, a urine test, a heart trace and a heart scan. You may also have a scan or X-ray.

Your trial doctor will phone you about a month later to see how you are. They will then phone you once every 3 months.

If you stop the trial treatment for any reason other than your cancer getting worse, you have a CT or MRI scan every 8 weeks until your cancer does start to get worse or you start another treatment. After that, the trial team will phone you every 3 months to see how you are getting on.

Side effects

BKM120 is a new drug so there may be side effects we don’t know about yet. The most common known side effects include

The most common side effects of fulvestrant include

  • Pain or swelling where you have the injections
  • Changes to the way your liver works
  • Feeling sick
  • Tiredness (fatigue)

We have more information about fulvestrant in our cancer drugs section.

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

Dr Andrew Wardley

Supported by

Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer

Questions about cancer? Contact our information nurses

Freephone 0808 800 4040

Last review date

CRUK internal database number:

Oracle 9940

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

Caroline took part in a clinical trial for breast cancer

“I had treatment last year and I want to give something back.”

Last reviewed:

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