A new UK-based clinical trial will evaluate existing cancer drugs as potential treatments for women living with metastatic breast cancer.

The study, led by Professor Janet Brown at the University of Sheffield and run by the Clinical Trials Research Unit at the University of Leeds, will evaluate radium-223 and avelumab – marketed as Bavencio by Pfizer and Merck KGaA – for the treatment of patients with oestrogen receptor-positive HER2-negative breast cancer that has spread to other parts of the body.

The researchers will analyse if this treatment combination leads to an improved immune response to secondary breast cancer in the bones and other sites in the body.

Currently, avelumab is used for the treatment of certain forms of secondary renal, advanced bladder and secondary skin cancers, while radium-223 is used to treat prostate cancer when it spreads to the bones.

The trial is being funded by The Breast Cancer Now Catalyst Programme – as part of the programme, Pfizer has provided Breast Cancer Now with funding through an independent medical research grant and provided the charity’s researchers with access to several of the company’s medicines.

“Although radium-223 and avelumab are approved for the treatment of other cancers, they have not been previously used in combination for breast cancer patients. We hope that this trial will see this combination treatment improve the immune response to secondary breast cancer in the bones and other sites in the body, as earlier research has suggested it could,” said Professor Janet Brown, chair in Medical Oncology and professor of Translational Medical Oncology at the University of Sheffield.

“This trial is an exciting chance to see if we can make immunotherapy work better, causing tumours in the bone and other secondary sites to shrink, which would significantly improve outcomes for people with secondary breast cancer,” she added.