Surrogate end-points in clinical practice: are we providing worse care?

摘要

In medicine, surrogate markers are biomarkers that substitute for clinical end-points known to predict clinical benefit or harm. A biomarker is a 'characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or phar-macologic responses to a therapeutic intervention'. The relationship of biomarker to surrogate is complex and is based on epidemiologic or clinical trial data or patho-physiological processes. The beauty of surrogate markers is in the relative ease and rapidity by which they may be acquired - imaging or biochemical tests as opposed to waiting years for clinical events to unfold. Surrogates can thus be used for diagnosis and staging as well as indicators of disease status and prediction or monitoring of response to an intervention.