Safety Questions Arise on Blood Clot DrugJan 17, 2006 | AP
A hemophilia drug has been linked to deaths, strokes, heart attacks and other complications in patients given the medicine for other types of out-of-control bleeding, such as cerebral hemorrhages, according to FDA researchers.
The medicine, NovoSeven, is a clotting drug that was introduced in 1999 after being approved by the Food and Drug Administration to stop bleeding in hemophiliacs. But it has also shown promise in treating cerebral hemorrhages, a potentially lethal type of stroke involving bleeding in the brain.
Most of the reported complications followed off-label use that is, uses for which the drug was not specifically approved by the FDA. Off-label use is legal, but doctors have less information on possible side effects of such uses.
The report on the complications appears in Wednesday's Journal of the American Medical Association.
The authors, including Dr. Kathryn O'Connell of the FDA's Center for Biologics Evaluation and Research, called for rigorous safety studies of new uses for the drug, which is made by the Danish pharmaceutical company Novo Nordisk.
NovoSeven got fast-track approval as an orphan drug, which means the company received financial incentives to develop it because it treats a rare condition and was seen as having little potential for profit.
Novo Nordisk AS said in a statement that off-label use of NovoSeven has resulted in complications in older people and those with underlying heart disease and acute injuries. The risk for approved uses "is thought to be low," the company said.
The company changed the warning in the package insert in October to include information on side effects in patients without hemophilia. Novo Nordisk said it is conducting studies on the safety of NovoSeven in such patients.
The researchers analyzed 431 reports to the FDA of adverse events, ranging from nausea to death, during the first five years of the drug's use. Drug makers are required to report such side effects when they happen during research on the drug after its approval. Doctors report them voluntarily.
In 185 cases, the drug's clotting action may have led to problems such as strokes and heart attacks, according to the study. Most of those problems followed off-label uses and happened within 24 hours of the last dose.
When it was introduced, NovoSeven was thought to be helpful for only the 10 percent of hemophilia patients who do not respond to standard treatments. The genetically engineered drug cost about $7,500 per dose.
Doctors have since found more uses for NovoSeven, including stemming bleeding from surgery, injuries or strokes. Use increased from 349 patients in 2000 to more than 4,500 in 2004.
"You're seeing people grasping for what's on the shelf now, hoping the evidence will follow," said Dr. James Meschia, a neurologist at the Mayo Clinic in Jacksonville, Fla.
Meschia's clinic has used the drug in life-threatening emergencies to try to stop bleeding in patients taking the anti-clotting drug warfarin. Since 2002, the clinic has used the drug off-label for seven patients and it caused no clotting difficulties, Meschia said.
In an October financial statement, Novo Nordisk reported global sales of NovoSeven increased 15 percent to $598 million for the first nine months of the year over the same period the previous year.
Last year, a study funded by the manufacturer and published in the New England Journal of Medicine showed NovoSeven can help patients with bleeding strokes. That study also turned up some complications, including heart attacks and strokes caused by blood clots.