Presentation (CTI)

OBJECTIVES: Indirect treatment comparisons (ITC) are frequently used to inform Health Technology Assessment (HTA) when direct head-to-head evidence is unavailable. However, their robustness and decision-making relevance depend on critical methodological and strategic choices. Indeed, appropriate choices can help address challenges such as cross-country variations in treatment practices, ethical constraints limiting global trials, and evolving treatment landscapes during trial conduct. This work provides practical guidance to support the design and conduct of ITCs in the context of HTA in France.
METHODS: A panel of experts in ITCs and French market access environment developed the present strategic guidance, informed by existing methodological frameworks, and challenges encountered in a systematic review of Transparency Committee opinions from the French National Authority for Health (HAS).
RESULTS: Recommendations are structured across three key pillars: planning, validity, and decision relevance. Early planning of ITC strategies is critical to ensure appropriate evidence generation aligned with HTA expectations. Ensuring internal validity requires systematic identification and justification of treatment effect modifiers, along with rigorous assessment of similarity and transitivity assumptions in randomized trial-based comparisons. For network meta-analysis, the structure of the evidence network should be adapted to the specific decision context, avoiding unnecessary complexity. For population-adjusted methods, maximizing decision relevance requires transparent reporting and careful interpretation of effective sample size, explicit discussion of limitations, and contextualized interpretation of results. When evidence relies on non-randomized clinical trials, external control arms may be considered, depending on the feasibility of conducting subsequent randomized studies, and provided that data comparability, bias mitigation, and methodological constraints are thoroughly addressed.
CONCLUSIONS: Robust and reliable ITCs require not only appropriate methods but also early planning and alignment with HTA expectations. This practical guidance offers actionable recommendations to strengthen evidence generation and HTA submission strategies in the French context.