Objective: To analyze buprenorphine prescription distribution across states in Medicaid patients during 2019-2020. Methods: Buprenorphine prescriptions per Medicaid enrollee per state was calculated for 2019 and 2020. The totals of monoproduct buprenorphine were divided over the total of combination buprenorphine/naloxone in 2019 and 2020 to obtain the ratio of mono/combo. Data analysis was conducted with generic and brand name formulations of buprenorphine, and transmucosal buprenorphine/ naloxone combinations FDA- approved for OUD using Microsoft Excel. Formulations of buprenorphine indicated for pain were excluded. States outside 95% confidence intervals (mean +1.96*SD) were considered statistically significant. Results: The overall change in buprenorphine prescribing between 2019 and 2020 was modest (+3.6%) but highly variable with > 10% increases in 17 states (Iowa = +100.5%, p < 0.05) but > 10% decrease in nine states (Alabama = -68.5%, p < 0.05). Total amount reimbursed in 2019 increased (+9.9%) to $1.42 billion in 2020. Branded formulations accounted for two-fifths (39.5%) of prescribing but over two-thirds (66.8%) of spending in 2020. There was a 50-fold difference in prescribing between the highest (Vermont = 219.5 prescription / 1,000 enrollees, p < 0.05) and lowest (Texas = 4.4) states in 2019. This disparity increased in 2020 resulting in a 278-fold difference. Conclusions: The COVID-19 pandemic exacerbated state-level disparities in buprenorphine prescribing for OUD among Medicaid patients. Legislation on buprenorphine waivered providers and Medicaid expansion may explain the statistically significant percent changes in state buprenorphine prescriptions. Keywords Medication for OUD; pharmacoepidemiology; COVID-19; medication policy

BJP was (2019-21) part of an osteoarthritis research team supported by Pfizer and Eli Lilly. The other authors have no disclosures.

BP receives funding from Health Resources Services Administration (D34HP31025). SRD was supported by the Geisinger Summer Research Immersion Program. No other funding noted.

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