August 5, 2005

Novartis and Schering AG are reevaluating the filing strategy for their experimental cancer treatment PTK/ZK after preliminary data from a Phase III trial showed the drug probably won't extend patients' lives.

The clinical setback occurred in the companies' CONFIRM 2 trial, which is examining PTK/ZK as a potential second-line treatment for metastatic colorectal cancer. A planned interim review of the trial by the companies' independent data safety monitoring board revealed a low probability that PTK/ZK would demonstrate an improvement in overall survival at final analysis, Novartis and Schering said.

PTK/ZK is widely considered one of Schering's most important drug candidates, as it is at the center of the company's previously announced strategy to build an oncology unit alongside its established gynecology/andrology, specialized therapeutics and diagnostics businesses. A setback would not be as costly for Novartis, which analysts say has a stronger pipeline than Schering.

The CONFIRM 2 results mark the second setback Novartis and Schering have suffered this year on PTK/ZK, which the companies were hoping would challenge the leading colorectal cancer treatment, Avastin (bevacizumab), marketed jointly by Roche and Genentech. In March, the companies posted disappointing interim results from its Phase III CONFIRM 1 trial, which failed to achieve its primary endpoint of performing better than standard chemotherapy in preventing colorectal cancer from worsening when administered in conjunction with chemotherapy. CONFIRM 1 is still ongoing with final overall survival results expected in the second half of the year.

In the wake of the CONFIRM 1 results, Novartis and Schering said they would delay their planned new drug application filing for PTK/ZK by a year to early 2007. A Schering spokesman said the companies will know more about the drug's filing status after they review further data to be released later this year.