A trial looking at ZD4054 for prostate cancer that has spread to the bones

This trial compared different doses of a new drug called ZD4054 for prostate cancer that had spread to the bones.

Doctors usually treat prostate cancer with surgery, radiotherapy or hormone therapy. But sometimes the cancer continues to grow, and when this happens it can be more difficult to treat.

Endothelin 1 (ET1) is a growth factor made by the body. It attaches to receptors on prostate cancer cells called endothelin A receptors. When ET1 binds to the receptor, it encourages the cell to grow and divide.

ZD4054 is a new type of biological therapy. It is called an ‘endothelin A receptor antagonist’. This means it stops ET1 attaching to the endothelin A receptor. Doctors hoped that if the ET1 could not attach to the receptor, it would not be able to tell the cell to grow and divide. But they were not sure how well it would work.

The aim of this trial was to find out how well ZD4054 worked for prostate cancer that had spread to the bones. And to find out more about the side effects of ZD4054.