Avastin, one of the world’s most popular cancer drugs, has been under intense scrutiny by the FDA while the agency works to determine whether or not to pull its approval of the drug as a treatment for breast cancer. In an effort to save one of its best-selling products, the drug’s manufacturer, Roche, has asked the FDA not to pull its approval until the pharmaceutical company can conduct additional studies to prove the effectiveness of Avastin when used along with another chemotherapy drug for the treatment of advanced breast cancer. In light of the recent controversy surrounding the drug, beginning on October 17, Blue Shield of California will no longer cover new Avastin prescriptions written for the treatment of breast cancer. Patients who are currently taking the medication will continue to be covered and exceptions could be made on a case by case basis, based on the findings of a panel of cancer experts. The California-based health insurer’s recent decision to stop covering Avastin for breast cancer is one of the more visible signs that Avastin may soon be difficult to come by. For the insurance company, the decision was prompted by a recent unanimous vote by an FDA advisory panel, in which Avastin was found to be ineffective and unsafe for the treatment of advanced breast cancer. Blue Shield is the largest health insurer thus far to stop covering Avastin, while three smaller insurance companies have also decided to stop their coverage of the breast cancer drug.