This study will last 4.5 years. Participants in this study will be randomly assigned to one of two treatment arms. Group 1 will receive LT-MAT with BUP/NX. Group 2 will receive ST-MAT with BUP/NX. An initial 4-week safety and feasibility phase will involve the first 50 participants at each site and will last approximately 30 weeks. Study visits will occur every week and will include a physical exam and blood and urine collection.