Background: Digital adherence technologies (DATs) with associated differentiated care are potential tools to improve tuberculosis (TB) treatment outcomes and reduce associated costs for both patients and healthcare providers. However, the balance between epidemiological and economic benefits remains unclear. Here, we used data from the ASCENT trial 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 with the standard of care in Ethiopia, with a difference of −0.4% (95% uncertainty interval (UI) −1.1%; +2.0%) incident TB episodes and −0.7% (95% UI −2.2%; +3.6%) TB deaths. However, our analysis also found large total provider and patient cost savings (US$163 (95% UI US$118; US$211) and US$3 (95%UI: US$1; US$5), respectively, over 2023–2035), translating to a 50.2% (95% UI 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% (95% UI 1.4%; 5.5%) reduction in incident TB and an 8.2% (95% UI 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.

Digital adherence technologies (DATs) could improve the person-centeredness of tuberculosis (TB) treatment. DATs are found to be acceptable, though evidence of their effectiveness is varied. Our objective was to understand the fidelity of DAT interventions within five cluster-randomized trials. Two DATs (smart pillbox, medication labels) were assessed, with real-time adherence data available to healthcare providers (HCPs) on a digital platform in Ethiopia, the Philippines, South Africa, Tanzania, and Ukraine. A framework assessed four components of implementation: inputs (training, support, mobile access), processes (SMS, home visits, platform usage), outputs (DAT engagement, manual dosing), and outcomes (people with TB (PwTB)–HCP relationship). Fidelity was evaluated by quantitative indicators, and content analysis of qualitative sub-studies supplemented some indicators. Engagement with DATs was high among PwTB. Pillbox users showed high levels of sustained engagement (box opening), with digitally recorded doses ranging from 82% to 91%. Differences were observed in login frequency by HCPs to the adherence platform. In Ethiopia, Tanzania, and Ukraine, there was at least one login to the platform on 71% of weekdays per facility compared with the Philippines and South Africa at 42% and 52%, respectively. Intervention fidelity varied among countries, suggesting a need for future work on optimizing implementation.