ABSTRACT More than half a million patients receive treatment at opioid treatment programs (OTPs) around the country, 95% of whom receive methadone as a medication for opioid use disorder (OUD), which is the gold standard for treating OUD. Current clinical practice for methadone medication treatment of OUD follows long-established federal and state regulatory policies that are highly restrictive and require patients to present in-person to a registered OTP every day to receive their prescribed methadone dose, creating an enormous obstacle to treatment that disproportionately impacts rural populations and low-income communities where lack of clinics, limited transportation, and/or inflexible jobs can make daily appointments difficult to sustain. This compliance burden contributes to program drop-out rates and adds to the public stigma surrounding OUD. States, OTPs, and other stakeholders have reported that a relaxation of federal policy during the COVID-19 pandemic, which allowed OTPs to prescribe longer take-home doses of medication to stable patients, had positive impact, resulting in increased treatment engagement, improved patient satisfaction with care, and few incidents of medication misuse. As a result, the U.S. Substance Abuse and Mental Health Services Administration (SAMHSA) has proposed making the changes permanent. However, many care providers remain reluctant to prescribe the full amount of allowable take-home doses due, in part, to ingrained stigmas and fears regarding overdoses and diversion of medication. To help overcome provider reluctance and increase confidence in take-home medication compliance, this Fast-Track project proposes the development of an unobtrusive wearable biosensor device capable of detecting and remotely monitoring a patient’s taken doses of methadone to enable trustworthy take-home methadone treatment options that can expand access to OUD healthcare. The core of CARI Health’s remote medication monitoring (RMM) system is an electrochemical sensor that can detect and quantitate methadone and its metabolite EDDP in human interstitial fluid (ISF) using differential pulse voltammetry and a custom microneedle array. To date, CARI has successfully created and tested prototypes of the proposed sensor, microneedle array, and assay. This project proposes to integrate these components into a prototype device and develop an accompanying device data pipeline in Phase I (Aims 1-3), then develop a commercial grade product (Aim 4), at-scale manufacturing processes (Aim 5), and clear the CARI RMM for human wearable use (Aim 6) during Phase II to prepare for testing the CARI RMM in clinical studies (Aims 7, 8) It is expected that successful achievement of the above aims will facilitate FDA clearance of a de novo class II device and begin the commercialization process of the CARI Health monitoring system, a timely innovation that will help maximize the impact of SAMHSA’s efforts to update regulatory policies to meet the recognized needs of OUD patients.

PROJECT NARRATIVE The proposed project will help bring to market a wearable biosensor, just-in-time intervention software, behavioral therapy mobile app, and related technical support for a remote monitoring system to enable trustworthy take-home treatment options for patients receiving medication for opioid use disorders. The CARI Remote Medication Monitoring system will use an electrochemical sensor in a self-adhesive wearable device similar to a glucose monitor to detect and quantitate methadone in human interstitial fluid and report the results in real time to care providers. When commercialized, the CARI system will enable opioid treatment programs to not only confidently implement more lenient, convenient, and safer take-home policies but also to provide better, objective, data-informed individualized treatment, which will make treatment more compelling for new patients and result in higher program retention.