Biomarkers, or biological markers, are signs that tell us something about the body. Examples include blood pressure, sputum, or levels of chemicals in the blood and urine.
Biomarkers tell us about how the body is working at a moment in time, and if there are signs of disease. Doctors and researchers often look at how biomarkers change over time. This can show if a person’s health is stable, improving or getting worse. Examples of biomarkers include blood pressure, sputum, or levels of chemicals in the blood and urine.
In clinical trials, biomarkers can show us if a treatment is working. They can also tell us about the safety of a treatment.