A powerful blood-clotting drug, NovoSeven, was approved by federal regulators in 1999 for a small number of patients with hemophilia or others who may bleed uncontrollably during surgery because they lack the gene that makes the clotting protein Factor VIIa.
A single dose of the drug, which is sold as NovoSeven, costs $10,000 but, The New York Times reports, it can be “a lifesaver” for these patients.
However, in the years since the Food and Drug Administration approved the drug for a narrow group of patients, doctors have widely prescribed it for “off label,” or unapproved, purposes. And that practice, according to two new studies by Stanford University researchers published in the journal Annals of Internal Medicine, raises the risk of many patients suffering a heart attack or stroke.
It is legal for doctors to prescribe drugs for purposes the FDA has not approved and, in the case of NovoSeven, many may feel there is a compelling reason to use it, because the medicine stops bleeding immediately. Still, researchers said its off label uses “far exceed” the purpose for which the agency sanctioned it. Consequently, the drug often is used in circumstances for which it has not been rigorously tested.
In one study, the Stanford researchers found that, in 2008, hospitals gave the drug 97 percent of the time to patients with other reasons for bleeding, such as heart surgery or a form of stroke, as well as body and brain trauma. “These patterns raise concern about the application of [the drug] to conditions for which strong supporting evidence is lacking,” the researchers wrote.
The other study analyzed the specific benefits and harms from five off-label uses of NovoSeven. The evidence from previous studies, it says, suggests “no mortality reduction” from those uses, while there is an increased risk of a blood clot in the heart or brain, resulting in a heart attack or the kind of stroke in which blood flow to a part of the brain is blocked.
In heart surgery, the researchers report, one out of every 20 people given the drug would be expected to have a serious clot in the heart or brain. “This is a powerful drug, and we don’t fully understand it,” Dr. Veronica Yank of Stanford, one of the authors on both papers, told the Times.
