Disappointment for Sirtex Medical with a preliminary analysis of its SIRFLOX clinical trial showing that the primary endpoint has not been achieved.
The preliminary analysis released on Tuesday shows that adding the company's SIR-Spheres Y-90 resin microspheres to a current first-line systemic chemotherapy regimen for the treatment of non-resectable metastatic colorectal cancer (mCRC) does not result in a statistically significant improvement in overall Progression-Free Survival (PFS).
"Based on the preliminary analysis just completed, the primary endpoint of the SIRFLOX study was not achieved," Sirtex said in a statement on Tuesday.
The company's shares were down around 50 per cent in response to the announcement, coming off significant growth since the start of the year as investors anticipated positive results from the trial.
Sirtex did announce that the trial results showed a statistically significant improvement in progression free survival in the liver.
"This secondary study endpoint is important as liver tumours are commonly the only, or dominant, site of disease in patients with mCRC and are the major site of disease influencing survival," the company said. "Up to 90% of mCRC patients die of liver failure due to the local effects of the liver tumours."
The SIRFLOX study results and preliminary analysis will be verified and validated through a peer review process, before being presented later this year.