Companion diagnostic

A companion diagnostic is a diagnostic test used as a companion to a therapeutic drug to determine its applicability to a specific patient. This technology is an assay that is developed during or after a drug is made available on the market and is helpful in enhancing the therapeutic treatment available based on the individual. These companion diagnostics have incorporated the pharmacogenomic information related to the drug into their prescription label in an effort to assist in making the most optimal treatment decision possible for the patient.

According to the FDA, ″A companion diagnostic is a medical device, often an in vitro device, which provides information that is essential for the safe and effective use of a corresponding drug or biological product. The test helps a health care professional determine whether a particular therapeutic product’s benefits to patients will outweigh any potential serious side effects or risks.

Companion diagnostics are co-developed with drugs to aid in selecting or excluding patient groups for treatment with that particular drug on the basis of their biological characteristics that determine responders and non-responders to the therapy.

Companion diagnostics are developed based on companion biomarkers, biomarkers that prospectively help predict likely response or severe toxicity.

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Wikipedia