Factors Affecting Buprenorphine Utilization and Spending in Medicaid, 2002-2018

Objective: Buprenorphine is an essential medication for the treatment of opioid use disorder (OUD), but studies show it has been underused over the last 2 decades. We sought to evaluate utilization of and spending on buprenorphine formulations in Medicaid and to evaluate the impact of key market and regulatory factors affecting availability of different formulations and generic versions. Methods: We first identified all buprenorphine formulations approved by the Food and Drug Administration for OUD using Drugs@FDA. We then used National Drug Codes to identify each drug in the Medicaid State Drug Utilization Data and extracted annual utilization rates and spending between 2002 and 2018 by drug and according to whether a brand-name or generic version was dispensed. We compared these trends to market and regulatory factors that affected competition, which we identified through searching the Federal Register, Westlaw, PubMed, and Google News. Results: Brand-name buprenorphine-naloxone sublingual tablet and film formulations (Suboxone) were dispensed 2.7 times more (n = 634 213 140) and reimbursed 4.4 times more (n = $4 440 556 473) than all other formulations combined (n = 237 769 689; $1 018 988 133). We identified numerous market and regulatory factors that contributed to an estimated 9-year delay in generic versions of the tablet formulation and 6-year delay for generic versions of the film formulation. Conclusions: Brand-name buprenorphine formulations have been widely used in Medicaid, leading to substantial costs, in part because generic versions were delayed by multiple years owing to market and regulatory factors. Timely availability of low-cost generics could have helped encourage OUD treatment with buprenorphine during the height of the opioid crisis.