Study finds link between industry payments and prescription practices for two cancer types

Physicians who received payment from pharmaceutical companies for meals, talks and travel were more likely to prescribe those companies' drugs for two cancer types, a University of North Carolina Lineberger Comprehensive Cancer Center-led study has found.

The study was published Monday in the Journal of the American Medical Association Internal Medicine. The preliminary findings were presented last year at the American Society of Clinical Oncology's Annual Meeting.

"The main takeaway is that oncologists who received money from a pharmaceutical company were more likely to choose that company's drug the following year," said Aaron Mitchell, MD, a fellow in the UNC School of Medicine Division of Hematology & Oncology, and the study's lead author.

For the study, researchers analyzed prescriptions for Medicare patients with two cancers where there are multiple treatment options: metastatic renal cell cancer (kidney cancer), and chronic myeloid leukemia, a blood cancer.

The researchers used publicly available data from 2013 to 2014 that was reported through Open Payments, a provision of the federal Patient Protection and Affordable Care Act that required U.S. drug and device manufacturers to disclose transfers of financial value greater than $10 to physicians and teaching hospitals.

Compared to physicians who didn't receive any payments, those who received general payments for meals and lodging from a drug manufacturer had higher odds of prescribing that company's particular drug for metastatic renal cell carcinoma and for chronic myeloid leukemia. For metastatic renal cell cancer, physicians who received any general payment in 2013 had twice the odds of prescribing that company's drug, and for chronic myeloid leukemia physicians who received any general payment had 29 percent higher odds of prescribing that company's drug.

The researchers did not find a consistent relationship for physicians who received payments from pharmaceutical companies solely for research.

An analysis of the data by individual drug type found a statistically significant decrease in the use of the leukemia treatment imatinib when physicians received payments. The same manufacturer made both imatinib and another treatment, nilotinib, Mitchell said. Since imatinib was about to lose its patent protection, the authors interpreted this finding to mean that payments from this company have been oriented towards "switching" physicians from the older drug imatinib to the newer drug nilotinib.

The researchers said the "proof-of-principle" study was meant to investigate whether there was an association between industry payments and prescriptions for cancer care, but researchers caution that it does not show a cause-and-effect relationship.​