(B-136) Utilization Trends of Methadone and Buprenorphine for Opioid Use Disorder in the US Medicaid population

Background: Buprenorphine and methadone are the most prescribed treatments for opioid use disorder (OUD) in the US. Medicaid, the largest US government program covering medications for opioid use disorder (MOUD), plays a critical role in addressing the opioid epidemic. However, the utilization trends of buprenorphine and methadone for OUD treatment among Medicaid enrollees are poorly described.

Objectives: To describe the utilization trends of buprenorphine and methadone for OUD treatment in the US Medicaid population

Methods: We conducted a descriptive study analyzing the prevalence of buprenorphine and methadone use for OUD treatment using a 100% Medicaid dataset from all 50 states. Methadone use was identified through Healthcare Common Procedure Coding System (HCPCS) procedure claims for administration at federally certified opioid treatment programs (OTPs). Buprenorphine use was identified through: (1) HCPCS procedure claims for administration in OTPs or other opioid treatment settings, and (2) National Drug Codes for buprenorphine products dispensed by pharmacies. For pharmacy-dispensed buprenorphine, we restricted the analysis to combination products with naloxone to infer their indication for OUD rather than pain. The estimated annual US Medicaid population was retrieved as denominators from the Medicaid and Children’s Health Insurance Program Payment and Access Commission Databook. We examined trends in MOUD prevalence from 1999 to 2020 across these three sources, and the trend in OUD prevalence among the US Medicaid population.

Results: The prevalence of OUD increased from 2.5 in 2000 (82,718), to 6.4 in 2010 (343,553), and to 17.8 in 2020 (1,314,644). From 1999 to 2020, methadone utilization at OTPs steadily increased, with prevalence per 1,000 patients rising from 0.5 in 2005 (n=21,146) to 1.3 in 2010 (n=71,540), to 3.1 in 2015 (n=213,272), and to 4.3 in 2020 (n=316,846). In contrast, buprenorphine administration at OTPs or other opioid treatment settings remained consistently low, with a prevalence less than 0.6 per 1000 patients annually throughout the period (n < 33,000). The prevalence per 1,000 patients of pharmacy-dispensed buprenorphine/naloxone increased from 0.2 in 2005 (n=10,817), to 1.6 in 2010 (n=87,196), to 3.7 in 2015 (n=254,526), and to 7.5 in 2020 (n=554,078).

Conclusions: There were large differences in utilization trends of methadone and buprenorphine. While methadone use at OTPs and pharmacy-dispensed buprenorphine/naloxone both showed substantial growth, buprenorphine administration in OTPs or other opioid treatment settings remained consistently low throughout the study period. Improving access to MOUD for untreated OUD patients remains critical in the Medicaid population.