Economics of Counterfeit Avastin: A Geospatial and Statistical Analysis of Demographic Correlates to FDA Warning Letters

Purpose: Warning notices were sent by the FDA to medical practitioners that may have obtained counterfeited versions of the angiogenesis cancer drug Avastin. The purpose of this study was to find differences between areas with counterfeit warning notices and those without counterfeit warning notices in order to discover how to direct counterfeit surveillance efforts so that they are best suited to protect cancer patients.

Methods: Addresses for warning notices send to individual healthcare practitioners were obtained from the FDA and then geocoded. Demographic variables chosen for analysis were thought to be capable of providing insight into economic factors associated with counterfeit Avastin exposure. These data were collected from the US Census Bureau or the Center for Medicare and Medicaid Services. All variables were analyzed at the U.S. county level.

Results: Our analysis uncovered 401 distinct counties where FDA sent counterfeit Avastin notices. In a multiple logistic regression model, the receipt of a notice was not significantly associated with percent uninsured (p = 0.3121), but was significantly associated with percent Medicare enrollees (OR = 0.874 per 10% increase; p = 0.0121), proportion below federal poverty line (OR = 2.990 per 10% increase; p < 0.0001), and median household income (OR = 2.698 per $10,000 increase; p< 0.0001).

Conclusions: Our study uncovers that county-level economic and demographic factors are potentially associated with counterfeit Avastin receipt after controlling for total number of people in each county. These findings can inform efforts to improve drug safety surveillance and protect patient populations.