State X-waiver Statutes and Buprenorphine Prescriber Rates Following Federal X-waiver Elimination, 2021-2023.

Abstract

This study examined whether U.S. jurisdictions that retained elements of the X-waiver in their statutes after federal elimination had lower buprenorphine prescriber rates than jurisdictions that did not retain such elements. Using a 25% random sample from IQVIA PharMetrics® Plus for Academics, data from January 2021-October 2023 (analyzed from 2025-2026) were modeled using Comparative Interrupted Time Series (CITS) models of monthly rates of unique buprenorphine prescribers per 10,000 eligible prescribers and jurisdiction fixed-effects generalized estimating equations (GEE). Jurisdictions were classified by whether they incorporated X-waiver language into their statutes, at the jurisdiction-month level, per the Center for Public Health Law Research at Temple University. Models were adjusted for three-month rolling opioid use disorder (OUD) diagnosis rates and annual age-adjusted opioid overdose mortality rates. Analyses were stratified by provider type. Three sensitivity analyses tested an alternative specification and excluded jurisdictions with unstable buprenorphine prescribing rates and enrollment. Forty-nine jurisdictions and 1,558 jurisdiction-months were included. Mean buprenorphine prescriber rates were higher in jurisdictions with X-waiver references than without (96.84 vs 47.01 buprenorphine prescribers/10,000 eligible prescribers). No differences in either level (-8.69 per 10,000 [95% CI: -19.96 to 2.59; p=0.131]) or trend (+0.74 per month [95% CI: -0.92 to 2.40; p=0.380]) of buprenorphine prescribers were found between jurisdiction-months with and without references to the X-waiver following X-waiver elimination. Findings were consistent across strata and sensitivity analyses. Findings suggest that removing jurisdiction-level statutory X-waiver references is unlikely to expand access, as structural barriers persist.