A First for FDA: Cancer Treatment Approved for Any Solid Tumor with a Specific Biomarker

The US Food and Drug Administration (FDA) on Tuesday granted accelerated approval to Merck’s Keytruda (pembrolizumab) for patients whose cancers have a specific biomarker.

FDA noted in a statement: "This is the first time the agency has approved a cancer treatment based on a common biomarker rather than the location in the body where the tumor originated."

Keytruda, an anti-PD-1 therapy that has been approved to treat a variety of cancers dating back to 2014, is now indicated for the treatment of adult and pediatric patients with unresectable or metastatic solid tumors identified as having a biomarker known as microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR).

According to FDA, MSI-H and dMMR tumors contain abnormalities that affect the proper repair of DNA and such tumors are most commonly found in colorectal, endometrial and gastrointestinal cancers, though also less commonly appear in breast, prostate, bladder, thyroid gland and other cancers.

Richard Pazdur, acting director of the Office of Hematology and Oncology Products in FDA’s Center for Drug Evaluation and Research and director of the FDA’s Oncology Center of Excellence, said: "This is an important first for the cancer community … Until now, the FDA has approved cancer treatments based on where in the body the cancer started—for example, lung or breast cancers. We have now approved a drug based on a tumor’s biomarker without regard to the tumor’s original location."

Further study is required by FDA to verify and describe anticipated clinical benefits of Keytruda, and the agency notes that Merck is conducting these studies in additional patients with MSI-H or dMMR tumors.

Merck’s application for this indication also received a priority review designation, which means FDA sped the review process to six months from the usual 10 months.