The labelling for Genentech’s Avastin cancer drug has been expanded in the USA to include second-line treatment, in combination with chemotherapy, of patients with metastatic colorectal cancer.

Avastin (bevacizumab) had already been approved by the US Food and Drug Administration as a first-line treatment for metastatic colorectal cancer in combination with regimens based on 5-fluorouracil (5-FU).

“This new indication offers colorectal patients who have received a previous treatment regimen a new option to help fight their disease," said Hal Barron, Genentech’s chief medical officer.

The new indication will lend further momentum to Avastin, already emerging as the cornerstone of Genentech and partner Roche’s oncology portfolio. Roche reported sales of the drug were $1.3 billion last year, its first full year on the market, while Genentech said it booked $1.1 million from the drug.

In addition to colorectal Genentech has filed for approval of Avastin in advanced breast cancer in combination with taxane drugs – with Roche due to follow suit in Europe later this year – as well as non-small cell lung cancer, while the firms are also investigating Avastin's potential in ovarian, pancreatic and renal cell carcinoma.

The latest approval was based on results of an 829-patient Phase III trial (E3200) involving colorectal cancer sufferers who had already seen disease progression despite earlier treatment with irinotecan and 5-FU. Avastin plus the 5-FU-based chemotherapy regimen known as FOLFOX4 (oxaliplatin/5-FU/leucovorin) achieved a 25% reduction in the risk of death, equivalent to a 33% improvement in overall survival, compared to patients who received FOLFOX4 alone.

Median survival for patients receiving Avastin plus FOLFOX4 was 13.0 months, compared to 10.8 months for those receiving FOLFOX4 alone, according to Genentech.