OPTIMIZING RETENTION, DURATION&DISCONTINUATION STRATEGIES FOR OPIOID USE DISORDER PHARMACOTHERAPY (CTN-0100). This contract is part of the NIH’s Helping to End Addiction Long-term (HEAL) initiative to speed scientific solutions to the national opioid public health crisis. The NIH HEAL Initiative bolsters research across NIH to improve treatment for opioid misuse and addiction. This study will continue to build the evidence-basis for better treatment of opioid misuse and addiction in order to stem the national opioid public health crisis.