Early end for AZ zibotentan study

AstraZeneca (AZ) has announced an early end to its phase III trial investigating zibotentan in prostate cancer patients due to negative results from an efficacy review.

The trial, which studied the effectiveness of zibotentan by itself in patients with non-metastatic castrate-resistant prostate cancer (CRPC), was halted after a review from an independent data monitoring committee indicated the drug was unlikely to meet its primary efficacy endpoints concerning progression free survival and overall survival.

A previous trial by AZ investigating zibotentan had already been stopped after negative results were recorded for use of the drug in men with CRPC that had metastasised. Both studies are part of the ENTHUSE programme.

A separate trial in the ENTHUSE programme, investigating the use of zibotentan in combination with chemotherapy in patients for whom the disease has metastasised, is set to continue. Results are expected in the second half of 2011.

The discontinuation of the trial follows the decision by the US Food and Drug Adminstration to deny approval for AZ's potential acute coronary syndrome therapy Brilinta (ticagrelor).

AZ also reported a decrease in profit of two per cent for the fourth quarter of 2010 in recent financial results.