Text Me, Alexis! is a three-arm randomized controlled trial (RCT) to determine the optimal (considering effectiveness and cost-effectiveness) intervention, or intervention combination for advancement along the HIV Care Continuum among trans women living with HIV (N=195). After screening, informed consent, and baseline assessment, participants will be randomized (1:1:1) into one of three arms: Peer Health Navigation (PHN) alone (n=65), SMS (text messaging) alone (n=65), or PHN+SMS (n=65). The study uses repeated assessments at baseline and at 3-, 6-, 12-, and 18-months post-enrollment, via an "intent-to-treat" design, where all assessments are administered to participants regardless of their engagement or retention. All intervention content is tailored and culturally responsive to trans women living with HIV.

Peer Health Navigation (PHN) alone. PHN is based on the theoretical foundation of Social Cognitive Theory. Participant-centered PHN helps to: (1) identify barriers to HIV care; (2) identify and link participants into needed auxiliary services; and (3) increase participants' self-efficacy in working with HIV care providers and other social service and treatment facilities. PHNs do not provide counseling or psychotherapy; rather, they work with each participant to successfully navigate complicated healthcare and social service systems. The PHN intervention utilizes an individualized, Participant-centered Treatment Plan with the specific goal of removing multiple and complex barriers that can impede linkage-to and retention-in HIV care, as well as the sustainment of medication adherence to achieve and maintain virological suppression. Each participant will work with a PHN to develop a Participant-centered Treatment Plan and get linked to HIV care or other needed auxiliary physical, mental health, and psychosocial services (e.g., hormone therapy, dental care, hepatitis testing/care, tuberculosis testing/care, substance use disorder treatment, mental health treatment, legal services, job training/development). If necessary, the PHN transports and accompanies the participant to and from her HIV care appointments (provision of transportation falls under the purview of PHN activities). The Participant-centered Treatment Plan identifies actions for the participant and PHN that must be taken by the next scheduled meeting, to help achieve short- and long-term goals, including participant access to needed behavioral health services, and advancement across the HIV Care Continuum. A priority of the first session is to schedule an HIV care appointment for the participant, if needed. The PHN also works with each participant to establish HIV self-efficacy regarding her treatment plan. Participants are introduced to a PHN immediately following randomization. PHN sessions are unlimited for 90 days.

Simple Message System (SMS \[text messaging\]) alone. Text messages are based on, and equally distributed across, three theories: Social Support Theory (SST), Social Cognitive Theory (SCT), and Health Belief Model (HBM). Participants receive three daily, theory-based text messages for 90 days (270 unique scripted messages), evenly arrayed across the three theories and the HIV Care Continuum. Text messages are scripted across: 1) HIV Care Continuum (HIV Positivity/Physical and Emotional Health, Linkage/Retention in HIV Care, and Antiretroviral Therapy (ART) Adherence/Viral Load Suppression); and, 2) theoretical foundation (SST, SCT, or HBM). Thus, each day participants receive one HIV Positivity/Physical and Emotional Health, one Linkage/Retention in HIV Care, and one ART Adherence/Viral Load Suppression message; each of which will be based on a theoretical foundation (SST, SCT, or HBM). Text messages are transmitted through gradual automation administration daily, including weekends, in real-time, within a 10-hour period, every five hours (e.g., at 12:00 PM, 5:00 PM, and 10:00 PM). Optimum hours were determined to be daily from 12:00 PM to 10:00 PM, though participants may personalize the schedule to any 10-hour period, and can choose to have the text messages delivered through their cell phone or email inbox. The automated text message delivery system was developed by Dimagi (dimagi.com). Dimagi designs clinical interfaces, health information systems, and mobile technologies to perform patient-level disease management, clinical decision support, and health system monitoring. To maintain interest and enthusiasm for the intervention, messages are systematically varied by theory and content, and participants never receive the same message twice. At the completion of the enrollment visit, a Research Assistant (RA) orients the participant to the SMS intervention.

PHN+SMS combined. Participants in the PHN+SMS arm will receive the same PHN and SMS interventions described above, but in concert to determine the effectiveness of the combined intervention when compared to PHN or SMS alone.