PROJECT SUMMARY/ABSTRACT For patients with advanced cancer, pain is a common and disabling symptom for which opioids remain a mainstay of treatment. The current epidemic of opioid misuse and addiction has led to widespread changes in opioid-related policies, including prescription drug monitoring programs (PDMPs) and laws limiting dose and duration of opioid prescriptions. Many such policies exclude patients with cancer; however, recent declines in opioid prescribing by oncologists and opioid use among patients dying of cancer highlight potential unintended consequences of opioid prescribing policies. Of particular concern is the potential impact on patients who are Black, low-income, elderly or reside in rural areas, since these groups are already at highest risk for inadequate pain treatment. To date, the impacts of opioid prescribing policies on patients with advanced cancer near end of life are not well understood. This represents a critical knowledge gap because understanding impacts of opioid-limiting legislation for patients with advanced cancer is essential to inform policies that effectively confront the dual public health crises of opioid misuse and inadequate pain treatment. This project investigates how state-level opioid policies can be structured to ensure safe and equitable opioid access for the roughly 600,000 adults who die from cancer annually in the United States. We will use over 10 years of claims data from Optum for national samples of patients with advanced breast, lung, and colorectal cancers near end of life. Patient data will be merged with detailed quarterly state policy data, which will be updated and synthesized with expert stakeholder input. In particular, we will examine the intended and unintended consequences of mandatory PDMP query laws, opioid prescribing cap laws limiting the dose/duration of opioid prescriptions, and state-specific cancer-related exemptions impacting opioid fills on patterns of use and pain-related outcomes. We will further investigate how state policy responses have impacted disparities in these outcomes. Finally, we will draw on stakeholder expertise to triangulate quantitative findings and inform policy recommendations. Our specific aims are to (1) assess impacts of state- level opioid prescribing policies on opioid access and end-of-life cancer pain management across a diverse national sample of decedents with advanced cancer using difference-in-difference models; (2) examine heterogeneity of policy impacts, with a focus on historically underserved patient groups; and (3) engage a stakeholder panel to inform, synthesize, and augment findings from Aims 1 and 2 and develop policy recommendations. This research will be the first analysis combining claims and policy data to comprehensively assess effects of state-level policies on opioid access, safety, and equity in this population. It will have a high impact because it will clarify impacts of wide-reaching opioid legislation for the more tha...