Surrogate markers

A surrogate marker (or surrogate end point) is term used in medical research for a change to the human body that is believe to be necessary to an eventual outcome or end point.Surrogate markers are used when it is unethical to look for the end point (e.g., death) in the experiment, or when the number of end point events is very small, thus making it impractical to conduct an experiment to look for the end point. The measurement of surrogate markers provides a way to test the effectiveness of a treatment for a fatal disease without having to wait for a statistically significant number of deaths to occur. the FDA will often accept evidence from clinical trials that show a benefit to surrogate markers instead of to end points.
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