Dose Determination Trial for Evidence-Based Behavioral Counseling to Improve HIV Care Engagement and Treatment Adherence

INTRODUCTION: The life-prolonging benefits of antiretroviral therapy (ART) are undermined by poor retention in care and suboptimal ART adherence. Although behavioral interventions have demonstrated efficacy in clinical trials and are widely disseminated, scaling up evidence-based interventions is hampered by not knowing answers to basic implementation questions, such as the minimally effective dose/minimum effective dose (MED) of counseling and how the MED varies across patients. This trial aimed to answer these questions. METHODS: People living with HIV in the southeastern United States (N = 295) who were either not engaged in care, nonadherent (2 sessions (ie, early dropout) of counseling. The MED for behavioral counseling on HIV care, adherence, and viral load was 5 sessions, with an MED range of 4-6 depending on counseling facilitators (eg, social support) and barriers (eg, medication concerns). CONCLUSIONS: Behavioral counseling in previous trials may have been underdosed when delivered in 6 sessions, depending on patient characteristics that moderate dose-response relationships.