Abstract Methadone is a highly effective treatment for opioid use disorder (OUD), but many patients leave treatment prematurely, placing them at high risk of relapse and overdose. Extensive research shows that comorbid cocaine use is associated with poor retention in methadone treatment. The proposed study will examine a novel intervention designed to improve methadone treatment retention and other outcomes among people with opioid and cocaine polysubstance use. The design is a 2-arm randomized controlled trial conducted over a one- year period following methadone treatment entry. Retention (primary) and drug use (secondary) outcomes for methadone treatment as usual (TAU, n=120) will be compared with the addition of the DynamiCare Health Contingency Management app (TAU+DCM, n=120). DCM is a personal digital therapy tool provided as an app on the patient’s smart phone. Its central feature is the delivery of evidence-based contingency management therapy in a convenient, remote, and fully automated fashion that ensures validity of target behaviors and immediacy of reward delivery. Two target behaviors relevant to retention will be the primary focus of the DCM program: 1) abstinence from opiates and cocaine as verified via remote oral fluid testing, and 2) medication pickup from the methadone program as verified by clinic records. Participants in the TAU+DCM arm will receive financial rewards for achieving these pre-determined behavioral targets over a 48-week intervention period. Comprehensive assessment of all participants will be conducted at baseline, 3-, 6- and 12-months. Aim 1: To determine the relative effectiveness of TAU+DCM compared to TAU alone in improving methadone treatment retention through 12-months post treatment entry. Aim 2: To determine the relative effectiveness of TAU+DCM compared to TAU alone in terms of [AIM 2a] reducing opioid use and cocaine use; and [Aim 2b] improving other secondary outcomes including non-targeted substance use and quality of life through 12- months post treatment entry. Aim 3: To explore app use patterns, acceptability, and perceived value of the personalized treatment intervention through 12-months post treatment entry. Innovation lies in the platform and structure of CM delivery that ensures treatment fidelity with automation of remote behavioral monitoring and reward delivery without involvement of clinical staff. This project represents a novel application of digital therapeutics to enhance the effectiveness of OUD treatment with polysubstance use. Findings from this project can improve the public health impact of methadone treatment by identifying an effective and scalable approach to address polysubstance use among patients at heightened risk of treatment dropout.

Project Narrative The proposed study is innovative in that it will examine treatment delivery via new and novel digital technology that offers patient personalization, since it is portable and can be used at the convenience and discretion of patients. The proposed study has significant public health implications as it represents an innovative and potentially effective strategy that could be easily integrated within our existing national OTP service delivery process to more effectively address polysubstance use involving opioids and stimulants, making it simultaneously novel and practical. As insurers, including Medicare and Medicaid, expand coverage of digital therapeutics, apps such as DynamiCare for CM delivery are poised to enhance existing treatment programs in a scalable and sustainable way.