What is a context of use (COU) for a biomarker?
The COU is a concise description of the biomarker’s specified use in in drug development. The COU includes two components: (1) the BEST biomarker category and (2) the biomarker’s intended use in drug development. Each biomarker qualification effort should identify a single COU.
A COU is generally written to be consistent with the following structure:
[BEST biomarker category] to [drug development use].
Examples of Biomarker Intended Use in Drug Development
- Defining inclusion/exclusion criteria
- Defining treatment allocation arms
- Cessation of a patient’s participation in a clinical trial
- Establishing a drug’s proof of concept in a patient population
- Supporting clinical dose selection
- Serving to enrich clinical trial for an event or population of interest
- Evaluating treatment response
Note that a drug development use may also include descriptive information such as the patient population, disease or disease stage or model system; stage of drug development; and/or mechanism of action of the therapeutic intervention.
See the graphic below for examples of how a biomarker category and drug development use are related.
BEST Biomarker Category and Examples of Corresponding Drug Development Uses
Examples of COUs
- Predictive biomarker to enrich for enrollment of a sub group of asthma patients who are more likely to respond to a novel therapeutic in Phase 2/3 clinical trials.
- Prognostic biomarker to enrich the likelihood of hospitalizations during the timeframe of a clinical trial in phase 3 asthma clinical trials.
- Safety biomarker for the detection of acute drug-induced renal tubule alterations in male rats
Important Information for Requestors
- Resources for Biomarker Requestors
- About Biomarkers and Qualification
- More About Biomarkers & Qualification
- General Biomarker Information
- 21st Century Cures Act
- Context of Use (COU)
- Biomarker FAQs
- BEST—a biomarker glossary
- Biomarker Qualification Submissions
- List of Qualified Biomarkers
- Letter of Support
Contact us at: CDER-BiomarkerQualificationProgram@fda.hhs.gov