News that Roche and Genentech’s Avastin has failed to show efficacy in pancreatic cancer threw an obstacle into the path of the product’s upwards momentum, but is unlikely to have a major impact on peak sales, according to analysts.

The Phase III trial looked at Avastin (bevacizumab) given in combination with Eli Lilly’s standard pancreatic cancer treatment Gemzar (gemcitabine) as first-line treatment for patients with advanced disease, but failed to show any benefit over Gemzar alone on overall survival. The 602-patients study – CALGB 80303 – was being carried out by the US National Cancer Institute.

Avastin – which has been described as a ‘pipeline in a drug’ - is already on the market for colorectal and filed for approval in non-small cell lung and breast cancer, collectively three of the most common malignancies. It is already a major earner for Roche and Genentech: the Swiss drugmaker recorded sales of $1.3 billion from Avastin in 2005, while Genentech said it booked $1.1 billion from the product. Analysts have suggested that peak sales could be as high as $4 billion, with the lion’s share of revenues coming from the ‘big three’ cancers.

But while the commercial implications of the disappointment may be slight, the in pancreatic cancer are a crushing blow to oncologists and their patients, who desperately need to find therapies that can increase survival in this particularly aggressive and difficult-to-treat disease.

“We will be further evaluating the data to understand potential reasons why this combination therapy did not lead to a clinical benefit in this trial,” said Eduard Holdener, head of global development at Roche.

Avastin may still have a role to play in pancreatic cancer, as Roche is carrying out another study of the drug in combination with Tarceva (erlotinib) on top of standard therapy, as part of an ongoing clinical programme with the drug in around 25 different tumour types.

The AVITA trial is due to complete patient recruitment by the end of 2006, and an interim analysis in April led the independent data safety monitoring board to recommend that it continue as planned.