Weigh Roche cancer drug toxicity, say FDA staff

Weigh Roche cancer drug toxicity, say FDA staff
A laboratory researcher in a file photo. Sanofi-Aventis SA sees space in the market for several rivals to Roche Holding AG and Genentech Inc's blockbuster cancer drug Avastin, Sanofi's head of oncology said on Wednesday. (Sebastian Derungs/Reuters)WASHINGTON (Reuters) - The benefits of Roche Holding AG'scancer drug Avastin in breast cancer should be weighed againstsome toxic side effects including the potential for death, U.S.regulatory staffers said in documents released on Monday.
The U.S. Food and Drug Administration staff review comesahead of a Wednesday advisory panel on a bid by Roche and U.S.partner Genentech Inc to extend use of Avastin, alreadyapproved to treat lung and colon cancer, to patients withbreast cancer.
The expert panel will give advice to the FDA on broadeninguse of the drug as a first-line treatment for patients withbreast cancer whose disease has spread.
The drug already reaps blockbuster sales, $2.65 billion inthe first nine months of this year.
In a key trial, the drug failed to extend overall survival,although it did meet its primary goal of extending"progression-free survival," the probability that a patientwill remain alive, without the disease getting worse.
A 5-1/2-month improvement in progression-free survival"must be weighted against the increased toxicity, includingdeaths associated" with the drug, FDA staffers wrote in anexecutive summary, posted on FDA's Web site.
Patients in the study were given either a commonly-usedtreatment called paclitaxel, or paclitaxel combined withAvastin, known generically as bevacizumab.
Among 722 total patients, those in the Avastin group had a20 percent increase in serious toxicity, includinghypertension, blood clots, and heart attacks, among other sideeffects, the FDA staff said.
Death attributed to the drug by the FDA was about 1.7percent of the Avastin group, versus zero in the control group.
The FDA staff disagreed with Genentech's causes of death insome instances.
"Most importantly," staffers wrote, in the Avastin arm"five out of twelve deaths were found to be possibly/definitelyrelated to" treatment.
Roche participation certificates, its most widely tradedform of equity, were 2.5 percent lower at 210.10 Swiss francsby 1439 GMT. Shares of Genentech were down 2.2 percent to$74.57 in morning trade on the New York Stock Exchange.
The briefing documents for the advisory meeting can befound at:http://www.fda.gov/ohrms/dockets/ac/07/briefing/2007-4332b1-00-index.htm
(Reporting by Kim Dixon; Editing by Tim Dobbyn)