Modelling the epidemiological and economic impact of digital adherence technologies with differentiated care for tuberculosis treatment in Ethiopia

Background Digital adherence technologies (DATs) with associated differentiated care are potential tools to improve tuberculosis (TB) treatment outcomes and reduce associated costs for both patient and healthcare providers. However, the balance between epidemiological and economic benefits remains unclear. Here, we used data from a large trial (PACTR202008776694999) to estimate the potential long - term epidemiological and economic impact of DAT interventions in Ethiopia. Methods We developed a compartmental transmission model for TB, calibrated to Ethiopia and parameterised with patient and provider costs. We compared the epidemiological and economic impact of two DAT interventions, a digital pillbox and medication labels, to the current standard of care, assuming each was introduced at scale in 2023. We projected long - term TB incidence, mortality and costs to 2035, and conducted a threshold analysis to identify the maximum possible epidemiological impact of a DAT intervention by assuming 100% treatment completion for patients on DAT. Findings We estimated small and uncertain epidemiological benefits of the pillbox intervention compared to the standard of care in Ethiopia, with a difference of - 0.4% ( - 1.1; +2.0) incident TB episodes and - 0.7% (- 2.2; +3.6) TB deaths. However, our analysis also found large total provider and patient cost savings [$163 ($118; $211) and $3 ($1; $5) million respectively over 2023 - 2035], translating to a 50.2% (35.9%; 65.2%) reduction in total cost of treatment. Results were similar for the medication label intervention. The maximum possible epidemiological impact a theoretical DAT intervention could achieve over the same timescale would be a 3% (1.4; 5.5%) reduction in incident TB and a 8.2% (4.4; 12.8) reduction in TB deaths. Interpretation DAT interventions, while showing limited epidemiological impact, could substantially reduce TB treatment costs for both patients and the healthcare provider.