The Breast Cancer Now Catalyst Programme

To achieve our aim that by 2050 everyone who develops breast cancer will live and be supported to live well, we need to speed up the translation of research in the lab into new and effective treatments for patients. We’re bringing together leading researchers and top pharmaceutical companies to pool ideas and resources and ultimately stop people dying from breast cancer.

As part of the Breast Cancer Now Catalyst Programme, we have collaborated with leading pharmaceutical company Pfizer to give researchers unprecedented access to a number of Pfizer’s licensed and investigative drugs as well as vital funding for researchers to test these drugs. This allows us to combine the expertise of our researchers with Pfizer’s compounds and deliver new treatments to patients more quickly.

Project details

Researcher: Dr Saskia Wilting

Location: Erasmus MC - Cancer Institute, The Netherlands

The challenge

When breast cancer spreads, whilst it can be treated, the disease can’t be cured. Once breast cancer has spread, it’s possible to manage it using combinations of drugs. But some cancers don’t respond as well as others and we don’t know why this is. We need to understand this to ensure everyone is receiving the most appropriate treatment for them, and to avoid any unnecessary side effects of treatment.  

Drug: Palbociclib

  • Blocks the activity of proteins called CDK4 and CDK6, which prevents cells from multiplying
  • Currently in Phase III trials in combination with other drugs for high risk early breast cancer
  • Already used to treat oestrogen receptor positive (ER+) HER2 negative breast cancer that has spread, in combination with hormone (endocrine) therapy

The science behind the project

For some people with oestrogen receptor positive (ER+) breast cancer that has spread, combining hormone therapy with a drug called palbociclib can provide precious extra months before their disease worsens. Dr Saskia Witling wants to develop a method to identify patients who would benefit from receiving palbociclib and those whose cancer will not respond to the drug, to save them from unnecessary side effects.

Currently, it takes three months to determine whether someone’s cancer is responding to palbociclib. This means that some people may be experiencing side effects associated with taking the drug, without receiving any benefit.

The researchers want to see whether a new method could be used to evaluate how cancers are responding to treatment more quickly. They are analysing blood samples donated by women taking part in the SONIA trial in the Netherlands. This trial is investigating whether it matters if palbociclib is given alongside hormone therapy in the first or second line of treatment for secondary oestrogen receptor positive breast cancer. The researchers are testing the levels of ‘circulating tumour DNA’ – fragments of cancer DNA found in the blood – in blood samples donated by participants.

They will determine whether this technique could more accurately indicate if breast cancer is no longer susceptible to hormone therapy alone and needs to be treated with palbociclib. They will also test whether this technique is quicker than currently available tests to indicate which cancers aren’t responding to palbociclib.

Ultimately, the team want to understand why palbociclib doesn’t work to treat some oestrogen receptor positive cancers. They will look at whether any genetic changes are present in the DNA from these tumours and whether this can explain why tumours respond differently to this drug.

What difference will this project make?

This research could show that a new test could be used to monitor how cancers are responding to hormone therapy and indicate who requires palbociclib. It could also help quickly identify people with cancers that don’t respond to this drug, saving them from any unnecessary side effects. Additionally, this project will improve our understanding of how resistance to palbociclib occurs, which could lead to potential new treatments for people with secondary oestrogen receptor positive breast cancer.

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* Pfizer has provided funding for this research study as an Independent Medical Research grant as part of the Breast Cancer Now Catalyst Programme. Pfizer has no other involvement in allocating the grants or conducting the research studies funded by the Catalyst Programme.