Patients receiving Avastin did have more severe side effects (74 percent to 75 percent versus 67 percent in the chemotherapy-alone group).
Final data on overall survival is not yet available. According to Dr. Eric Weiner, director of the breast oncology center at Dana-Farber Cancer Institute in Boston and moderator of the Saturday news conference, "it is unlikely there will be a survival benefit."
The U.S. Food and Drug Administration tends to approve second and third-line drugs based on progression-free survival and drugs for the first-line setting on survival, Weiner said, adding that he "personally does not understand that approach."
Progression-free survival can be seen as a quality-of-life improvement. "Having the disease under control for longer, as long as the toxicity of treatment is not substantial, is something that is well worth it," Weiner said. "So a drug that can substantially improve profession-free survival is a drug that can at least, in some patients, make their lives that much better while they are dealing with this illness."
More information
The American Society of Clinical Oncology has more information on breast cancer.
