Generic utilization and cost-sharing for prescription drugs.

Purpose: The purpose of this study is to estimate the own- and cross-price elasticity of brand-name outpatient prescription drug cost-sharing for maintenance medications and to estimate the effects of changes in the price differential between generic and brand-name prescription drugs.

Methodology/approach: We first review the literature on the effects of an increase in brand-name drug patient cost-sharing. In addition, we analyze two examples of utilization patterns in filling behavior associated with an increase in brand-name cost-sharing for patients in employer-sponsored health plans with chronic illness.

Findings: We found that the own-price elasticity of demand for brand-name prescription drugs was inelastic. However, the cross-price elasticity was not consistent in sign, and utilization patterns for generic prescription fills did not always increase after a rise in brand-name cost-sharing.

Research Limitations: The empirical examples are limited to the experience of patients with employer-sponsored health insurance.

Practical Implications: The common practice of increasing brand-name prescription drug patient cost-sharing to increase consumption of generic drugs may not always result in higher generic medication use. Higher brand-name drug cost-sharing levels may result in discontinuation of chronic therapies, instead of therapeutic switching.

Originality/value Of Chapter: The value of this chapter is its singular focus on the effects of higher brand-name drug cost-sharing through a synthesis of the literature examining the own- and cross-price elasticity of demand for brand-name medications and two empirical examples of the effects of changes in brand-name cost-sharing.