Novartis has suffered a setback with the news that a late-stage trial of its investigational prostate cancer treatment patupilone has failed to meet its primary endpoint.

The Swiss major says that patupilone, also known as EPO906, did not show a significant overall survival advantage in a Phase III trial of patients with advanced ovarian cancer who were refractory or resistant to platinum-based therapy The comparator arm in the study was Johnson & Johnson’s Doxil/Caelyx (pegylated liposomal doxorubicin).

The study, conducted in 168 sites in 22 countries, saw 829 patients randomly assigned to intravenous patupilone (10 mg/m2) once every three weeks or Doxil (50 mg/m2) once every four weeks and were evaluated for disease status by scans every eight weeks until disease progression. Novartis did not give any details about secondary endpoints included progression-free survival, safety and overall response rate but noted that no new or unexpected serious adverse events in the patupilone arm were identified in the trial.

However, the company said it does not plan to proceed with regulatory filings based on these data. Still, this may not be end of the road for the compound, which belongs to a class of microtubule stabilisers called epothilones. It is still being evaluated in ongoing trials in multiple tumour types, including metastatic colorectal cancer, brain metastases in non-small cell lung cancer and hormone-refractory prostate cancer.

Analysts had not held out any great hopes for patupilone but Novartis had expected to file the drug for ovarian cancer this year, giving special mention to the compound at a presentation of its oncology pipeline in December.