Introduction: In 2017, funding disseminated through the US Substance Abuse and Mental Health Services Administration's Opioid State Targeted Response (STR) program accelerated the expansion of peer recovery support services across several states to engage emergency department patients presenting with opioid use disorder. While there is some literature on the initial implementation of these programs, little is known about their sustainability after the STR funding's end. Identifying what happened to these programs is a key component of understanding their ultimate impact and can inform future activities to develop, fund, or sustain similar efforts. Methods: We collected qualitative data from six organizations that participated in Indiana's STR-funded Recovery Coaching and Peer Support Initiative (RCPSI). The semi-structured interview guide was designed to gather data related to eight domains of sustainability (i.e., environmental support, funding stability, partnerships, organizational capacity, program evaluation, program adaptation, program evaluation, communications, and strategic planning). The analysts followed a deductive-inductive analysis approach, using the eight domains as an a priori coding structure and developing higher-level inductive themes. Results: A total of ten individuals (roles included 4 Program Supervisors, 2 Nurse Administrators, a Psychiatric Social Worker, a Mobile Treatment Manager, a Grant Coordinator, and a Vice President of Planning) participated in six interviews. Two programs did not sustain services, primarily because they lacked a sufficient volume of eligible patients to justify services. Factors identified as supporting sustainability in the other four programs included (1) identification of alternate funding sources, (2) evolving internal support for ED-based opioid use disorder treatment, and (3) investment in internal and external relationships. Furthermore, these themes operated across multiple sustainability domains. Conclusions: The findings illustrate a dynamic interplay between program context and multiple theorized sustainability domains that impacted the viability of RCPSI programs after the end of STR funding. Results indicate a need for a better understanding of the factors influencing the sustainability of programs supported by federal funding to mitigate the opioid crisis, and such findings will likely apply to a broader range of grant-supported programs.
