Promotion and market share in the proton pump inhibitor market: A case study

This case study of the proton pump inhibitor market examines prescription volume, promotional spending, and their interrelatedness between the years 2000 and 2004. Our results show that share of voice and share of market are strongly correlated (r² values from 0.79 to 0.91) and that the temporal relationship is clear: share of market follows share of voice. Exogenous market factors such as generic entry and over-the-counter entry disrupt the relationship between share of market and share of voice and influence the decision to advertise. For example, generic entry increased pantoprazole (Protonix®) advertising (p < 0.05) while over-the-counter availability decreased rabeprazole (Aciphex®) and pantoprazole advertising (p < 0.01 and p < 0.05, respectively). In comparing the different promotional media, direct-to-consumer advertising did not statistically significantly increase prescription volume, but physician-directed advertising was related to an additional 43,662 prescriptions for every 1% increase in share of voice (p < 0.001). For marketing managers, our study demonstrates the relationship between share of voice and share of market and sheds light on the relative effectiveness of advertising strategies in the proton pump inhibitor market.