Genentech has presented more promising late-stage data which suggests that its blockbuster Avastin, marketed with Roche, is indeed an effective treatment for breast cancer.

The US biotechnology firm says that a 1,237-patient Phase III study, called RIBBON 1, of Avastin (bevacizumab), in combination with taxane, anthracycline-based or capecitabine chemotherapies for first-line treatment of metastatic HER2-negative breast cancer, met its primary endpoint of increasing the time patients lived without their disease advancing, compared to the chemotherapies alone. The safety profile of Avastin was consistent with previous experience and no new safety signals were observed, Genentech noted.

Hal Barron, chief medical officer at Genentech, said the findings of this study, together with the positive PFS results from the E2100 and AVADO Phase III trials, “support Avastin’s ability to delay cancer progression with commonly used chemotherapies in metastatic HER2-negative breast cancer”. He added that the firm will discuss these data with the US Food and Drug Administration as part of its bid to get full approval of Avastin for advanced breast cancer.

In February, the FDA conditionally approved the drug providing Roche and Genentech file additional data. However, the RIBBON 1 study "should help to convert the accelerated approval granted in February to full approval and hence make marketing easier," said analysts at Deutsche Bank in an investor note.

Dr Barron added that Genentech plans to submit the data from RIBBON 1 and AVADO to the FDA by mid-2009. Analysts believe that full approval could push US Avastin sales for breast cancer alone could reach $1.3 billion.