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: Professor Bryan Hennessy and Dr Alex Eustace

Location: Royal College of Surgeons in Ireland, Dublin

The challenge

We need to find new targeted treatments for breast cancer that are more tailored to a person’s tumour than treatments like chemotherapy. This will improve the chances of survival for people with breast cancer and reduce potential side-effects.

Drug: Gedatolisib

  • Gedatolisib is a drug that blocks two proteins, PI3K and mTOR, which can help breast cancer cells to multiply uncontrollably
  • Gedatolisib is currently in early stage clinical trials to treat oestrogen receptor positive (ER+) breast cancer
  • Many other drugs that block PI3K are in various stages of development for breast and other cancer types

The science behind the project

Gedatolisib belongs to a group of drugs called PI3K inhibitors. They are currently being tested to treat a variety of different cancers with changes in a gene called PIK3CA.

Professor Bryan Hennessy, Dr Alex Eustace and their team have found that PI3K inhibitors could also be effective against breast cancer cells with changes in a group of genes called the ‘ERBB-family’. These genes are commonly mutated in breast cancer and other cancers. One of the four genes in the ERBB family, HER2, drives the disease in around 20% of breast cancers.

In this project, Bryan and Alex are further investigating what makes breast cancer cells sensitive to gedatolisib. Using a range of breast cancer cells grown in the lab, they study how changes in the ERBB-family genes and the PIK3CA gene, make breast cancer more susceptible to gedatolisib.

Bryan and Alex are also testing gedatolisib in combination with drugs such as lapatinib, which is used to treat secondary HER2 positive breast cancer. They believe HER2 positive breast tumours are also susceptible to gedatolisib.

Finally, the researchers will test gedatolisib and HER2-blockers in mice that carry samples of breast tumours donated by patients, to find the most effective combination which could be tested as a treatment for people with breast cancer in the future.


What difference will this project make?

Gedatolisib and other PI3K inhibitors are already being tested in people with breast and other cancers. Bryan and Alex’s research will help to identify which patients are most likely to benefit from gedatolisib. It will also reveal whether gedatolisib on its own or in combination with HER2-blocking drugs would be most effective. Ultimately their research could help provide a new targeted treatment to improve chances of survival for people with breast cancer.

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* Pfizer has provided funding and Pfizer compounds 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 this research study.