Generics in Medicaid increased in price and shifted to larger manufacturers amid 2022-2023 amphetamine shortage.

INTRODUCTION

In late 2022, several manufacturers of immediate-release (IR) amphetamine-based stimulant drugs reported shortages to the FDA. Regulatory requirements for amphetamine and other controlled substances, such as manufacturer-specific quotas set on raw materials, may exacerbate shortage effects on price and quantity.

METHODS

Using 2018-2024 Medicaid State Drug Utilization Data, we studied the impact of the 2022-2023 amphetamine shortage on spending, spending per prescription (ie, prices), and dispensing of amphetamine products.

RESULTS

Despite a significant decline in prescriptions dispensed per enrollee following the shortage announcement, gross spending per enrollee increased by 7% between 2022-Q2 and 2023-Q1. Prices for generic IR products increased by 6% between 2022-Q2 and 2023-Q1 and accounted for more than half of spending growth. Changes in prescription volume varied significantly by manufacturer, with relatively stable trends through the shortage for larger generic manufacturers and sharp declines for smaller manufacturers.

CONCLUSION

Despite substantial government oversight in controlled substance markets, prices increased for generics during the shortage. Differences in dispensing across manufacturers implied that, in Medicaid, larger firms adapted more effectively to supply disruptions.