[Surrogate end points--somewhere between essential and not worth discussing].
1Zentrum für Sozialpolitik (ZeS), Universität Bremen, Bremen. gglaeske@zes.uni-bremen.de
Summary
Surrogate markers in medical care, especially drug therapy, often fail to reflect true patient outcomes. Rigorous validation is crucial, as many markers can lead to patient harm instead of benefit.
Area of Science:
- Clinical research methodology
- Pharmacovigilance
- Evidence-based medicine
Background:
- Surrogate markers are frequently used in clinical trials to predict treatment efficacy.
- However, their reliability in demonstrating true patient-related outcomes, particularly in drug therapy, is often questionable.
Purpose of the Study:
- To critically evaluate the utility and limitations of surrogate markers in assessing patient outcomes in medical care.
- To highlight instances where reliance on surrogate markers has led to adverse patient events.
Main Methods:
- Review of existing medical literature and clinical trial data.
- Analysis of case studies where surrogate markers were employed.
Main Results:
- Many surrogate markers show correlation but do not reliably capture treatment effects on true patient outcomes.
- Several examples demonstrate that treatments based on surrogate markers have resulted in increased harm and mortality (e.g., hormone therapy, vitamin supplements, osteoporosis treatments).
Conclusions:
- Most surrogate markers are inadequate for demonstrating patient-related outcomes and should be used sparingly.
- Rigorous validation of any surrogate marker is essential to prevent patient harm and ensure therapeutic benefit.
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