Models of service delivery for optimizing a patient's first six months on antiretroviral therapy for HIV: an applied research agenda.

Differentiated models of service delivery (DSD models) for HIV treatment in sub-Saharan Africa were conceived as a way to manage rapidly expanding populations of experienced patients who are clinically "stable" on antiretroviral therapy (ART). Entry requirements for most models include at least six months on treatment and a suppressed viral load. These models thus systematically exclude newly-initiated patients, who instead experience the conventional model of care, which requires frequent, multiple clinic visits that impose costs on both providers and patients. In this open letter, we argue that the conventional model of care for the first six months on ART is no longer adequate. The highest rates of treatment discontinuation are in the first six-month period after treatment initiation. Newly initiating patients are generally healthier than in the past, with higher CD4 counts, and antiretroviral medications are better tolerated, with fewer side effects and substitutions, making extra clinic visits unnecessary. Improvements in the treatment initiation process, such as same-day initiation, have not been followed by innovations in the early treatment period. Finally, the advent of COVID-19 has made it riskier to require multiple clinic visits. Research to develop differentiated models of care for the first six-month period is needed. Priorities include estimating the minimum number and type of provider interactions and ART education needed, optimizing the timing of a patient's first viral load test, determining when lay providers can replace clinicians, ensuring that patients have sufficient but not burdensome access to support, and identifying ways to establish a habit of lifelong adherence.