AZ's oral prostate cancer drug fails another Ph3 trial

AstraZeneca's late-stage cancer drug zibotentan has tumbled against yet another hurdle. Investigators for the company say they have decided to write off a Phase III prostate cancer study after determining that non-metastatic patients taking the oral drug weren't likely to live longer than the patients on standard therapy. That follows another bad ending for a separate late-stage trial last fall, when AstraZeneca announced that it was tearing up plans for a regulatory filing.

However, the company has one more shot on goal. It is continuing a trial of zibotentan in combination with chemotherapy in patients whose prostate cancer has gone metastatic. But hopes for the drug, once considered a possible alternative to Dendreon's hot new prostate cancer therapy Provenge, appear to be dwindling fast. Researchers decided to make an early call on the second late-stage study as the data continued to mount against the drug.

"AstraZeneca felt it was prudent to take an early view on the progress of Study 15 following the announcement in September 2010 that ENTHUSE Study 14, evaluating zibotentan monotherapy, did not show a significant improvement in the primary endpoint of overall survival in patients with metastatic CRPC," the company said in a release.

Last fall, researchers reported that zibotentan's survival benefit in a Phase II study was actually narrower than had been first reported, dropping below the level of statistical significance. And the setbacks represent fresh trouble for AstraZeneca, which has also been hit with trial failures for Recentin in colon cancer and Vandetanib in non-small cell lung cancer.

Special Report:  Zibotentan - Top 10 Phase III Failures. Report 

- here's the AstraZeneca release
- get the Bloomberg report