Byetta, a diabetes drug sold by Indianapolis-based Eli Lilly and Co. and San Diego-based Amylin Pharmaceuticals Inc., may
be giving a “false sense of security” to doctors and patients about potential cancer risks, a top U.S. drug reviewer
Data on intravenous dosing and an extended-release form of Byetta “seem to give a similar signal” as cancers seen in rodent studies of Novo Nordisk A/S’s competing Victoza, chemically known as liraglutide, said Curtis Rosebraugh, head of the Food and Drug Administration’s Office of Drug Evaluation II, in a Jan. 25 memo posted Friday on the agency’s Web site.
Novo Nordisk, of Bagsvaerd, Denmark, won FDA approval for Victoza in January after 10 months of delay because of safety concerns. The agency recommended against using the daily shot as an initial treatment for diabetes until additional studies are completed to assess a potential risk of thyroid tumors.
“Our internal data indicates that the preclinical findings are not unique to liraglutide but will probably extend to all” similar long-acting diabetes drugs, Rosebraugh said. “So to condemn liraglutide would be to condemn them all.”
Kindra Strupp, a spokeswoman for Lilly, didn’t return a phone call seeking comment. Anne Erickson, a spokeswoman for Amylin, didn’t immediately return a voice-mail message for comment.
The FDA delayed a decision on a proposed once-weekly version of Byetta on March 15 and asked for more information on manufacturing, labeling and a risk-management plan. No new studies were ordered. The companies plan to sell the drug under the brand name Bydureon.
The drug approval is key for both companies. Byetta, taken as a twice-daily injection, has been successful for controlling blood-sugar levels in patients and helping some lose weight. It racked up $797 million in worldwide sales last year.
But analysts expect a once-weekly injection of Bydureon to be far more attractive because of its convenience. Analysts expect sales of Bydureon to reach as high as $2 billion by 2015.
Amylin's stock fell 24 cents, or 1 percent, to $23.65 per share Friday morning. Lilly shares rose 13 cents each, to $36.65.
Almost 24 million Americans have diabetes, caused by a lack of insulin needed to convert blood sugar into energy, according to the National Institutes of Health. Most have the Type 2 form of the disease linked to older age, excess weight and physical inactivity.
Both Victoza and Byetta, now sold as a twice-daily shot, belong to a new class of diabetes medicines that imitate a hormone called GLP-1 to stimulate the pancreas to produce more insulin after meals.