* What: FDA advisory panel to vote on Avastin
* When: Two-day hearing starts on Tuesday
* Lack of new evidence makes approval unlikely-analysts
* Almost $1 billion in Avastin sales at stake
* Private insurance may still pay, not Medicare-analyst
WASHINGTON, June 26 (Reuters) -- Drugmaker Roche Holding AG (ROG.VX) will try to convince U.S. regulators to reverse course on Avastin, the world's best-selling cancer medicine, and approve its use for breast cancer in a hearing this week.
But analysts say the Food and Drug Administration, which proposed removing the breast cancer indication in December, is unlikely to change its opinion without new evidence about Avastin's ability to help breast cancer patients live longer.
"There seems to be only a very slim chance that Avastin will stay on the market for breast cancer," said Tim Race, analyst at Deutsche Bank in London. "It would be a major U-turn for the FDA ... and there would be quite a lot of fallout from such a change of stance."
For Swiss-based Roche, a FDA decision could shave off almost a billion dollars in annual Avastin sales, according to analysts.
And for patients, an FDA rejection of the appeal could mean insurance companies would stop covering the expensive drug, potentially jeopardizing treatment for an estimated 17,000 women currently using the medicine, advocates say.
After skin cancer, breast cancer is the second-leading type of cancer among women, according to the Centers for Disease Control.
SURVIVAL VERSUS QUALITY OF LIFE
Avastin won U.S. clearance for breast cancer in 2008 based on a study showing the drug stalled cancer growth by 5.5 months. As part of an accelerated approval, the FDA required Roche to run follow-up studies to confirm the drug worked. For timeline, see [ID:nN1E75M15P]
Later studies found only a one- to three-month delay in breast cancer growth. And no studies showed Avastin extended the lives of patients with advanced breast cancer.
The drug also had side effects, including holes in the stomach and intestines, severe bleeding and blood clots.
In December, the FDA proposed revoking Avastin's clearance for breast cancer while keeping the drug on the market for colon, lung, brain and kidney cancers. For details, see [ID:nLDE6BF1T7]
Genentech, a Roche unit, has been fighting the decision, saying the extension of time without cancer growing was meaningful for patients with advanced breast cancer. At that stage, the disease cannot be cured and the goal is to stabilize patients as much as possible.
"We looked at metastatic cancer, where almost everyone will have a recurrence of their disease," said Dr. Philippe Bishop, head of global clinical development for Avastin. "We look for how long a patient can live without their disease getting worse."
Roche also claimed the rate of side effects was low, less than 4 percent in breast cancer trials.
Stripping the breast cancer indication for Avastin would not prevent doctors from using it. But without FDA approval, insurers may refuse to pay Avastin's $8,000-a-month price tag. And Genentech would not be able to promote Avastin for that use.
Many breast cancer groups and U.S. lawmakers were outraged by the FDA's December decision on Avastin, charging it was based on cost, something the FDA is forbidden from doing. They also accused the agency of trying to limit patient options and dictate medical care.
In a rare move, the FDA granted Genentech an appeal, allowing the company to make its case at a public hearing on Tuesday and Wednesday. It is the first time the agency has had an appeal hearing over its decision to withdraw the breast cancer indication under accelerated approval, the FDA said. [ID:nN24296745]
Dr. Stanley Waintraub, a chief of breast oncology at the John Theurer Cancer Center at Hackensack University Medical Center in New Jersey, plans to testify in favor of Avastin.
He said 17,000 women in the United States are currently using the medicine, including some of his patients.
"I have been a doctor since 1977, and I have been in oncology since 1982," he said. "I have watched too many patients die. This drug works. It doesn't work all the time. But nothing works all the time, not even an aspirin.
"If the FDA opposes this drug, it would be a horrible day in history for patients in this country."
FOCUS ON GENETIC MARKERS
Most analysts believe the panel will not change its mind, especially as five of the six panelists voted against Avastin's use in breast cancer at a hearing last July.
This time around, panelists will also have an option to keep Avastin's indication for breast cancer, pending further Roche studies that show a more significant clinical benefit.
"They do have an opportunity to say that there's not a lot of harm that can be done while we wait (to see) what happens with that additional trial," said Ira Loss, an analyst with Washington Analysis. He thinks it's possible the breast cancer use will not be removed completely.
Roche has also said it plans to run studies that could pinpoint genetic markers to identify who would best respond to Avastin. The FDA has said it is open to any new research that can identify specific types of women likely to benefit.
"Roche has been searching for years for the right biomarker. At this point, it would be an unexpected outcome if the FDA decided to preserve the label while they're waiting for that data," said Morningstar analyst Karen Andersen.
IMPACT ON SALES
Analysts estimate about $1 billion of Avastin's more than $6 billion in yearly sales come from breast cancer uses. The product used to be Roche's top-selling drug, and some expected it to become the world's biggest-selling drug by 2014.
But its prospects have dimmed after doubts about its benefits in breast cancer and after it failed in clinical trials for prostate and stomach cancer.
Morningstar's Andersen said her projections for Roche's overall earnings would not be greatly affected by the FDA's decision. Avastin is still used for breast cancer in other countries, and European authorities relaxed curbs on the drug in April after initially restricting use. [ID:nLDE73E12N]
An FDA revocation would likely see Medicare, the U.S. federal health insurer, cut coverage for the drug, shrinking U.S. sales by half in 2011 to $400 million, Andersen said.
She sees a 60 percent chance that private health insurers would still maintain coverage for Avastin on an off-label basis. (Reporting by Anna Yukhananov, additional reporting by Ben Hirschler in London; editing by Michele Gershberg and Jeffrey Benkoe)