Physicians know FDA-OK'd uses for drugs half the time

A 2006 Archives of Internal Medicine study of 725 million prescriptions found that about one in five orders was written off-label -- that is, for a condition that has not received the Food and Drug Administration's approval as a safe and effective use of the drug. More than 70% of these off-label prescriptions were for indications in which the drug ordered had little or no scientific support.

The results of a new survey in the Aug. 21 Pharmacoepidemiology and Drug Safety add more cause for concern, experts said. Four in 10 doctors queried about 22 medications believed at least one of the drugs was FDA-approved for a given indication when it was not so labeled and lacked scientific evidence backing the prescribing decision.

For example, 51% of primary care physicians who prescribed budesonide-- marketed as Pulmicort by AstraZeneca plc -- for chronic obstructive pulmonary disorder wrongly believed it was FDA-approved for that condition. Such an order is not only off-label but contradicts peer-reviewed evidence of ineffectiveness.

The national survey of nearly 500 randomly sampled primary care physicians and psychiatrists found that 55% of the time, doctors correctly identified the FDA-label status of drugs for particular indications.

FDA labeling "is not the primary source of information that guides clinical prescribing, and in many cases this [off-label approach] may be appropriate," said study co-author G. Caleb Alexander, MD, assistant professor of medicine at the University of Chicago Pritzker School of Medicine. "But physicians' erroneous beliefs about FDA labeling are especially important in cases where drugs have been demonstrated to be ineffective or have unacceptable risks."

Particularly alarming, Dr. Alexander said, was that about one in five doctors who prescribed quetiapine -- marketed as Seroquel by AstraZeneca -- for dementia with agitation believed the FDA had approved the drug for that treatment. In fact, at the time of the survey the FDA had warned doctors against off-label use of the drug in patients with dementia.

An AstraZeneca spokeswoman said it has always been the company's policy "to promote its medicines in accordance with FDA regulations and to train its sales force to follow this policy."

All this information about indications can overwhelm physicians.

"It is terribly, terribly hard for an individual practitioner to keep abreast of all the thousands of indications," said Jerome L. Avorn, MD, chief of the division of pharmacoepidemiology and pharmacoeconomics at Brigham and Women's Hospital in Massachusetts.

Dr. Avorn, author of the 2004 book, Powerful Medicines: The Benefits, Risks, and Costs of Prescription Drugs, blamed the confusion over FDA labeling and the prescribing evidence base on industry marketing.

"Much of what doctors know about drugs comes from what they learn from the industry because the industry is out there actively communicating with doctors through sales reps or sponsoring continuing medical education programs," Dr. Avorn said.

Dr. Avorn runs the Independent Drug Information Service, which is active in Pennsylvania, Massachusetts and the District of Columbia.

High-profile cases show drugmakers get into trouble promoting off-label prescribing, he said. For example, in 2004, Pfizer Inc. and state and federal authorities reached a $430 million settlement over the company's marketing of Neurontin (gabapentin). Pfizer admitted no wrongdoing.

In January, the FDA issued clarifications on when and how drugmakers could reprint scientific articles showing evidence for off-label uses.

The American Medical Association responded to the guidelines when they were proposed last year. AMA Executive Vice President and CEO Michael D. Maves, MD, MBA, noted it's important for doctors to have "timely access to accurate and unbiased information about unlabeled uses of drugs and medical devices."

University of Chicago's Dr. Alexander said future efforts should concentrate on how to help doctors avoid dangerous drugs and make better clinical decisions. "We need to develop new methods of disseminating information regarding the evidence base of prescription drugs that will more effectively reach" physicians, he said.