Since the development of the first companion diagnostic for Herceptin was introduced more than 10 years ago, the development paths for these tests have followed the same formula: stratify patients by identifying a single marker that can predict the likelihood that a single therapeutic will or won’t be an effective form of treatment.

From a clinical standpoint, a companion diagnostic (CDx) seeks to close the gap between a “one size fits all” approach to using a drug and a tailored approach to using the drug in an individual patient. The bulk of the companion diagnostics available for clinicians target oncology drugs and have been developed as researchers have come to better understand the mechanisms, pathways, and manifestations of cancer, all helping to answer the age-old conundrum of why certain patients respond to therapy while others show no improvement.

In short, a companion diagnostic helps clinicians determine the safest and most effective use of a drug for only those patients who stand to benefit from it. On the flip side, it also helps avoid unnecessary treatment for patients who won’t respond, which allows doctors to seek alternate treatment routes right away—an especially important consideration for oncologists to avoid wasting time on ineffective treatment. A CDx test can also help identify patients that may have a significant adverse reaction to a drug.

For the rest of the story, click here.

Also of Interest