Merck files for FDA approval of Keytruda in lung cancer

By Deena Beasley (Reuters) - Merck & Co Inc said on Sunday it has submitted an application to the U.S. Food and Drug Administration for its drug Keytruda as a treatment for advanced non-small cell lung cancer, the most common form of the disease. Keytruda, also known as pembrolizumab, is currently approved by the FDA for patients with advanced melanoma who are no longer responding to other therapies. The drug is part of a new class designed to help the body's own immune system fend off cancer by blocking a protein known as Programmed Death receptor (PD-1), or a related target known as PD-L1, used by tumors to evade disease-fighting cells. Merck said the FDA submission is based on trial data in patients for which testing showed that at least half of their tumor cells contained PD-L1. Those trial results will be presented later on Sunday at a meeting of the American Association for Cancer Research in Philadelphia. Keytruda was previously designated by the FDA as a "breakthrough therapy" for advanced NSCLC. Merck said it is seeking approval for use of the drug in patients whose disease has worsened after treatment with chemotherapy or other medications. Merck also said a pre-marketing authorization was submitted by Dako North America, a unit of Agilent Technologies Co, for a companion test to diagnose patient levels of PD-L1. (Reporting By Deena Beasley; Editing by Diane Craft)