The day after a panel of experts advised the Food and Drug Administration to go ahead with plans to revoke approval of Avastin to treat breast cancer, European authorities moved in the opposite direction.

The European Commission gave the OK to an expansion of Avastin's approval to include using the drug in combination with Xeloda, a chemotherapy drug, to treat metastatic breast cancer, Genentech parent company Roche said Thursday.

The Europeans considered the same information that hasn't proved persuasive to U.S. regulators. Among other things, a study called RIBBON 1 found Avastin plus Xeloda increased progression-free survival of women by 2.9 months over women getting Xeloda alone.

 

In a statement, Genetech's Chief Medical Officer Dr. Hal Barron said the company is "pleased with this outcome because it means that women with metastatic breast cancer and their physicians will now have an additional treatment option in Europe."

The diverging decisions show how two regulators can reach different conclusions about the clinical significance of the same data.

In explaining its decision to seek the withdrawal of Avastin's fast-track approval for breast cancer, the FDA wrote last year about data from RIBBON 1 and other studies:

The addition of Avastin to chemotherapy resulted in only a small delay in tumor growth (i.e., progression-free survival, PFS), and the average time it took for tumors to progress seen in these trials was much shorter than had been expected based on the data from an earlier trial that led to accelerated approval.