For the millions of people living with HIV in high-tuberculosis-burden settings, the gap between clinical trial evidence and real-world outcomes has long been a critical unknown. This large multicountry analysis closes that gap meaningfully, demonstrating that tuberculosis preventive treatment retains its protective power even under the programmatic conditions of modern antiretroviral therapy rollouts — a finding with direct implications for how aggressively national health systems should prioritize TB prevention alongside HIV treatment.
The PROTECT study used target trial emulation — a rigorous epidemiological approach that mimics randomized trial design using observational data — to analyze electronic health records from six countries spanning Sub-Saharan Africa, the Caribbean, Eastern Europe, and West Africa: Haiti, Kenya, Nigeria, Uganda, Ukraine, and Zimbabwe. Enrolling people with HIV who initiated antiretroviral therapy between 2018 and 2022, the study defined TPT exposure during an 8-week grace period after ART initiation and tracked outcomes through 2023–2024. The primary endpoints were tuberculosis incidence and all-cause mortality. Adjusted hazard ratios were calculated individually per country and then pooled via meta-analysis — a design that accounts for the substantial heterogeneity in health systems, TB burden, and patient populations across these settings.
What makes this study particularly valuable is its contemporary scope. Previous randomized evidence on TPT was largely generated before the era of universal ART eligibility regardless of CD4 count, raising legitimate questions about whether the TB-preventive benefits would persist when patients are starting treatment earlier and with generally healthier immune profiles. This study suggests the answer is yes — TPT remains meaningfully effective in the modern treatment era. The target trial emulation framework strengthens causal inference beyond standard observational analysis, though residual confounding cannot be fully excluded. The cohort design also captures adherence and retention patterns reflecting real-world programmatic delivery, making these estimates arguably more actionable for policy than RCT results. Taken together, this is a confirmatory and programmatically significant contribution — not paradigm-shifting in concept, but important in validating TB prevention strategies at scale.