Novel chemotherapies more often used on- than off-label

(HealthDay)—In contemporary practice, medical oncologists use novel anticancer agents on-label more often than off-label, according to a study published online Feb. 19 in the Journal of Clinical Oncology.

To examine the prevalence of off-label use of 10 commonly prescribed patent-protected anticancer drugs, Rena M. Conti, Ph.D., of the University of Chicago, and colleagues analyzed prescribing data from a pharmacy software provider maintaining a population-based cohort database including 570 medical oncologists in 122 medical oncology practices.

The researchers found that 70 percent of chemotherapy use was on-label, and 30 percent was off-label. Fourteen percent of chemotherapy use conformed to an off-label indication supported by the National Comprehensive Care Network (NCCN) recommendations. Ten percent of off-label use occurred at a U.S. Food and Drug Administration-approved cancer site but for a stage of cancer or line of therapy that was not recommended by the NCCN. Spending on these chemotherapies amounted to $2 billion for off-label and NCCN supported uses and $2.5 billion for off-label and NCCN unsupported uses, compared with $7.3 billion for on-label uses.

"The overall proportion of off-label use that the authors identified is not high, especially when taking into account NCCN-approved indications, but the variation by drug and the associated costs are high," write the authors of an accompanying editorial. "The ultimate goal should not be zero off-label prescribing, but rather that the entire system be designed to maximize the likelihood of an optimal risk-benefit ratio for both individual patients and the system as a whole."

One author disclosed financial ties to Genentech; a second author is an economic expert for plaintiffs in suit against the manufacturer of rituximab.