For the first time in the Agency’s history, the FDA has approved a drug based on genetic abnormalities instead of the organ in which the disease is located. The FDA made the landmark decision for pembrolizumab, an antibody-based drug used for advanced solid tumors with microsatellite instability-high (MSI-H) or mismatch repair deficiency (dMMR) that have not responded well to previous treatments. Cells in advanced solid tumors with MSI-H or dMMR are unable to repair their own DNA errors, which can lead to cancer. MSI-H or dMMR cells are most commonly found in colorectal, endometrial and stomach cancers, and patients with these types of cancers generally do not respond well to chemotherapy treatments. The FDA’s decision was based on an “accelerated process,” which means that the Agency can revoke its approval if pembrolizumab is not successful in treating patients in clinical studies.

Usually, health care insurance providers hesitate in covering broad genetic tests for cancer, but the FDA’s approval of pembrolizumab is projected to serve as good news in encouraging insurance companies to do so more often. With increasing evidence of specialized medicines and treatments helping patients combat their illnesses, insurance providers will be more likely to pay for personalized tests. However, only a small percentage of patients respond to drugs such as pembrolizumab, and scientists are still researching why this is. By uncovering more biomarkers and genomic indicators to understand why the same cancer manifests differently in patients, researchers will be able to develop comprehensive treatments that would increase the odds of success in treating cancer patients.

Source: Xconomy