Abstract
PURPOSE: In South Africa, an estimated 62% of female sex workers (FSW) are living with HIV. Oral HIV pre-exposure prophylaxis (PrEP) is effective, but FSWs' PrEP use typically declines rapidly post-initiation in service settings. We examined a pilot individualized case management (ICM) intervention aiming to increase PrEP adherence and persistence among cisgender FSW initiating PrEP in eThekwini, South Africa. To assess pathways of intervention influence and potential effectiveness, we characterize the support participants received from the case manager (CM) and the ways in which it influenced their PrEP adherence and persistence. METHODS: FSW initiating PrEP through a non-governmental key populations program (n = 29) participated in the pilot ICM sessions for 12 weeks, as well as semi-structured, in-depth interviews (IDIs) at baseline, month 1, and month 3. We triangulated the IDIs with CM observation notes and PrEP program refill data through month 4. We coded textual data thematically, and produced narrative summaries and time-ordered matrices to summarize themes, assess changes over time, and compare participants who continued versus discontinued PrEP by month 4. We employed the "capability, opportunity, and motivation - behavior (COM-B)" system in interpreting the pathways through which the CM's support influenced participants' PrEP adherence and persistence and considering potential intervention enhancements. RESULTS: The CM provided emotional, instrumental, and informational support that positively influenced participants' PrEP use capability, opportunity, and motivation. She bolstered participants' PrEP use capability by providing reminder tools and information to manage side effects and dispel misunderstanding; opportunity by helping strategize covert PrEP use in the face of stigma, and directly resolving pill access problems stemming from mobility and housing insecurity; and motivation by providing care and accompaniment. Experiences of care, accompaniment, and other emotional support from the CM were deeply felt in context of sex work stigma, and more prominent in the narratives of participants continuing PrEP at month 4 (20/29; 69%) versus those who discontinued. Still, 31% (9/29) of participants discontinued PrEP, and key influential forms of CM support required her ongoing presence. CONCLUSIONS: Findings suggest both pathways of potential ICM effectiveness and impact and sustainability shortfalls, calling for larger-scale evaluation and complementary structural approaches, such as those bolstering FSW social cohesion and tackling socio-economic barriers.