Priscilla Howard, who has metastatic breast cancer, has been taking the drug Avastin for a little more than two years and has seen a remarkable difference in the progression of her disease, she told a panel of experts at the U.S. Food and Drug Administration during the first day of a two-day hearing that pits the FDA's Center for Drug Evaluation and Research against Genentech, Avastin's manufacturer.
"I am progression free but not cancer free," said Howard, one of a handful of Avastin patients who gathered both inside and outside the FDA to fight for keeping Avastin on the market.
"I want every available weapon in my arsenal as I fight this devastating disease," Howard told the panel. The hearing will ultimately decide the fate of what some patients consider a lifesaving drug.
Although a handful of breast cancer patients testified Tuesday that Avastin helped in treating their metastatic breast cancer, a review of studies conducted by the FDA's Center for Drug Evaluation and Research suggests the risks outweigh the benefits of Avastin for treating breast cancer, FDA officials said at the hearing.
The FDA granted an accelerated conditional approval for Avastin in February 2008 to treat late-stage breast cancer patients. It had been suggested that the drug slowed the progression of the disease and improved overall survival.
But results from four trials that enrolled more than 3,000 women found no significant reduction in progression of the disease or improvement of death rates among those who took Avastin and underwent chemotherapy.
"The decision must be based on the totality of evidence in all clinical trials," Dr. Richard Pazdur, director of the FDA's Office of Oncology Drug Products, said at the hearing Tuesday. "The totality of data submitted to FDA shows it's not safe and effective [for treating] breast cancer."
The hearing is the culmination of recommendations to begin regulatory withdrawal of the drug for use on breast cancer patients. Some cancer specialists said the decision could hold huge implications for the way their patients will be treated.
"This decision [could] remove an option for patients," said Dr. Edith Perez, clinical oncologist at the Mayo Clinic.
American Cancer Society's deputy medical officer Dr. Len Lichtenfeld attended the hearing and tweeted "No one has asked the question: What do we say to all the patients and families who testified this morning?"
Crystal Hanna, 35, a mother of two from Parkersburg, W. Va., said she's certain she would not be alive today if it wasn't for Avastin. Hanna, who was diagnosed with stage 4 breast cancer in July 2010, said her cancer hadn't progressed and she was still taking Avastin.
"We're not just statistics," Hanna told ABC News. "I have a lot to live for. I am here to plead with them to have compassion for our life."
Doctors had previously reported seeing their patients benefit by taking Avastin, but it's not clear which patients it helps the most.
"We will be working hard to make sure that patients who are getting Avastin and seeing good control of their cancer will continue to get Avastin with their treatment," Dr. Gretchen Kimmick, medical oncologist at Duke University Medical Center, told ABC News in December.
Still, the FDA studies found no overall benefit from the drug, and even suggested that some patients increased their risk of death because Avastin is, in some ways, toxic.
The panel asked whether the FDA's experts who testified believed that some patients could benefit from Avastin.
"No, we do not agree," Dr. Patricia Keegan, director of the FDA's Division of Biologic Oncology Products in the Office of Oncology Drug Products, said.
"Despite the hopes of everyone inside and outside this room," Keegan testified, "there is no evidence that Avastin saves or extends lives."
ABC News' Lisa Stark contributed to this report