Impact of Medicaid Prescription Cap Policies on Treatment Outcomes for Opioid Use Disorder: A National Mixed Methods Study - PROJECT SUMMARY More than 2 million people have opioid use disorder (OUD) in the U.S. and opioids accounted for 70% of the nearly 100,000 drug-overdose deaths in 2020. Increasing OUD prevalence and opioid-involved overdose deaths underscore the urgent need for improved access to effective OUD treatments. Methadone, buprenorphine, and naltrexone are effective in treating OUD, yet these medications for OUD (MOUD) are underutilized, particularly among low-income Medicaid beneficiaries who represent a sizable portion of the U.S. population living with OUD. Prescription (Rx) caps represent a cost-containment strategy employed by some state Medicaid programs that limit the number of brand name drugs or total number of prescriptions that may be filled each month. Rx cap policies potentially exacerbate the opioid epidemic by impeding access to MOUD among financially constrained Medicaid beneficiaries, many of whom have comorbid chronic health conditions (e.g., mental illness, chronic pain, HIV), and who are forced to make tradeoffs between which medically necessary medications to fill. Though a few older studies have used Medicaid data to evaluate the impact of Rx caps on the health of the general population, until now, this has not been studied among people with OUD – an NIH priority population. The objective of this application is to examine whether and how Medicaid Rx caps affect the care and health of people with OUD and other chronic health conditions. Our long-term research goal is to develop an evidence base that can be used to revise medication utilization management policies in ways that balance budget priorities with improved patient and population health outcomes. Our central hypothesis is that Rx caps contribute to reduced uptake of and continuity with MOUD treatment, resulting in increased overdoses and mortality. The rationale for this hypothesis is that people with OUD frequently have co-occurring conditions and are likely to require several simultaneous prescriptions to manage their health, placing them at risk for exceeding the caps. Our skilled team of health services researchers, pharmacists, clinicians, and epidemiologists has extensive experience using Medicaid claims data and qualitative methods to study the impact of health policies on marginalized populations. We propose to analyze national Medicaid data to evaluate the impact of Rx cap policies on initiation and continuity of MOUD use among individuals diagnosed with OUD; and determine the impact of Rx cap policies on health services utilization, overdoses, and all-cause mortality among this population. We will then contextualize our quantitative findings via interviews with patients with OUD and providers who practice in states impacted by cap policies to elucidate their experiences with caps and identify best practices for navigating these policies. Completion of this research will help to close critical knowledge gaps by generating novel mixed-method findings on Rx drug coverage for OUD treatment and yield best-practice recommendations for navigating cap policies. As states continue to consider strategies to address the worsening opioid and overdose crises, due attention should be given to Medicaid benefit restrictions that can undermine individual and public health goals.