Understanding whether the combination of a new kinase inhibitor and palbociclib could be used to treat triple negative breast cancer

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.

Around 15% of breast cancers are classed as triple negative. This form of breast cancer can be more aggressive than other forms of the disease. Triple negative breast cancer disproportionately affects younger women and black women. One of the key issues that patients face is that there are currently limited targeted treatments available for triple negative breast cancer. We urgently need to find new ways to treat this form of breast cancer.

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

A drug palbociclib is currently used to treat some forms of breast cancer. But it doesn’t work well to treat triple negative breast cancer. Dr Helfrid Hochegger, who is based at the University of Sussex, has discovered a way to make palbociclib more effective against triple negative breast cancer. Helfrid and his team want to better understand whether inhibition of an additional protein involved in cancer growth could be used together with palbociclib to treat people with triple negative breast cancer.

The researchers will find out how these two drugs work together to stop breast cancer growing. They will look at single breast cancer cells as well as laboratory models of the disease to better understand triple negative breast cancer. Helfrid and his team will also investigate how these two drugs can complement each other at the molecular level. They hope this knowledge will also help to understand whether the same treatment approach could be used for other breast cancers that are resistant to palbociclib.

Helfrid’s work will lay important foundations for understanding how a new combinatorial treatment with palbociclib could be used to treat triple negative breast cancer. It could also help to understand which triple negative breast cancers would be susceptible to this treatment. If results are positive, the hope is that this research could lead to clinical trials and eventually a new treatment to help improve the survival of people with triple negative breast cancer.