Effects of televised direct-to-consumer advertising for varenicline on prescription dispensing in the United States, 2006-2009

background: Televised direct-to-consumer advertising (DTCA) for prescription drugs is controversial, especially for tobacco cessation products such as varenicline, given mixed evidence of varenicline’s effectiveness as well as safety concerns that arose only after its market approval. We aim to quantify the extent to which DTCA influenced varenicline use.

methods: We linked monthly Nielsen DTCA television ratings with monthly data from IMS Health’s National Prescription Audit to examine relationships between DTCA for smoking cessation aids and varenicline prescribing across 75 media markets. We used Poisson GEE models to analyze effects of exposures to DTCA for both varenicline and nicotine replacement therapies (NRT) on varenicline prescriptions among smokers, controlling for population characteristics and varenicline-related events.

results: Varenicline prescriptions increased dramatically following DTCA launch and declined sharply after safety risks were made public: sales dropped by 40% in 6 months after the FDA public health advisory. Varenicline DTCA had significant impact on new prescription volume in the subsequent month: before the FDA advisory, one additional exposure to varenicline DTCA was associated with a 1.8% higher rate of new prescriptions (p<.0001); while no effect was observed after the advisory (RR=1.0, p=0.95). Cross-product effects of NRT advertising on varenicline prescribing were significant after the FDA advisory (RR=1.015, p<.0001), while the effects were negligible before the advisory (RR=1.002, p=0.14).

conclusions: DTCA for varenicline had a significant impact on varenicline prescribing during a time when the drug’s safety profile was not fully understood, supporting arguments to limit DTCA for newly-approved products whose real-world safety is particularly unclear.