State X-Waiver Statutes and Buprenorphine Prescriber Rates After Federal X-Waiver Elimination, 2021-2023

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 those that did not retain such elements.

Using a 25% random sample from IQVIA PharMetrics Plus for Academics, data from January 2021 to October 2023 (analyzed from 2025 to 2026) were modeled using comparative interrupted time series models of monthly rates of unique buprenorphine prescribers per 10,000 eligible prescribers and jurisdiction fixed-effects generalized estimating equations. 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 3-month rolling opioid use disorder 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 in those without (96.84 vs 47.01 buprenorphine prescribers/10,000 eligible prescribers). No differences in either the level (-8.69 per 10,000 [95% CI= -19.96, 2.59; p=0.131]) or trend (+0.74 per month [95% CI= -0.92, 2.40; p=0.380]) of buprenorphine prescribers were found between jurisdiction-months with and without references to the X-waiver after 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 because structural barriers persist.