Researchers at Stanford University, the University of Illinois-Chicago and the University of Chicago have proposed 14 widely prescribed medications they say most urgently need additional study to determine how effective and safe they are for off-label uses. Their study and proposals were published in the December Pharmacotherapy.
The study targeted drugs with high levels of off-label use without good scientific backing. At the top of the list was AstraZeneca's Seroquel for treating schizophrenia.
The researchers say it leads all other drugs on the list in its high rate of off-label uses with limited evidence. Other drugs on the list are warfarin, escitalopram (Lexapro and Cipralex), risperidone (Risperdal), montelukast (Singulair), bupropion (Wellbutrin), sertraline (Zoloft), venlafaxine (Effexor), celecoxib (Celebrex), lisinopril (Prinivil, Zestril), duloxetine (Cymbalta), trasodone (Desyrel), olanzapine (Zyprexa), and epoetin alfa (Procrit, Epogen).
“Off-label prescribing means that we're venturing into uncharted territory where we lack the usual level of evidence presented to FDA that tells us these drugs are safe and effective,” said Stanford University associate professor of medicine Randall Stafford, the senior author. “This list of priority drugs might be a start for confronting the problem of off-label use with limited evidence.”
The most common off-label use for six of the 14 drugs cited was for bipolar disorder. “Many of the drugs and the conditions on the list represent situations where inadequate response to treatment is common and where drug side effects are frequent,” Stafford said. “Not only are these areas where patients and physicians are naturally interested in trying off-label therapies, but (they are) areas targeted for expansion by the makers of these drugs. When the volume of off-label use of any drug reaches the magnitude that we're documenting, it suggests a role of the pharmaceutical industry in facilitating these types of uses.”