AstraZeneca has revealed that its Phase III study of zibotentan for the treatment of men with metastatic castration resistant prostate cancer (CRPC) did not meet its primary endpoint of overall survival.

Zibotentan is a once-daily tablet that blocks the endothelin pathway, which slows tumour growth and metastasis.

The placebo-controlled and randomised study, part of Enthuse clinical trials programme, evaluated zibotentan 10mg when added to the standard of care treatment in 594 men with CRPC.

Two other trials, designed to evaluate zibotentan in different CRPC settings, are being conducted as a part of the Enthuse clinical programme.

CRPC is a form of prostate cancer which is unresponsive to the treatments that block the testosterone action.