Objectives: Clinical endpoints are defined as valid measures of clinical benefit or harm due to treatment, that describe the impact of treatment on how a patient feels, functions, and survives. The choice of endpoints and the manner in which they are reported have a major impact on the relative effectiveness assessment (REA) of pharmaceuticals. The aim of this article is to describe the guideline development process and the key findings that set a framework for appropriate use of endpoints in REAs in Europe.

Methods: A multi-health technology assessment (HTA)-agency collaborative process in EUnetHTA JA1 was used to scope, draft, and finalize methodological guidelines for REA in Europe.

Results: Patient-relevant clinical endpoints can be broadly categorized into: mortality, morbidity and health-related quality of life. A clinical endpoint is a main symptom or sign of a disease that is clinically relevant, valid, reproducible and responsive to change. Preference is for long-term or final endpoints whenever possible. Surrogate endpoints may be used when there is compelling evidence of a clear and consistent correlation of treatment effects on the surrogate and final outcome of interest.

Conclusions: The relevance and hierarchy of the different types of clinical endpoints depend on the research question, disease, and the treatment investigated. Not only the primary endpoint, but also other relevant endpoints are assessed in comparison to adequate comparator(s). This simultaneous assessment of all relevant endpoints is a hallmark of REA.