The U.S. Food and Drug Administration on Friday approved an immunotherapy drug for the treatment of advanced non-small cell lung cancer.
Keytruda (pembrolizumab) can be used to treat advanced non-small cell lung cancer in patients whose disease has progressed after previous treatments and who have tumors that express a protein called PD-L1, the agency said.
"Today's approval of Keytruda gives physicians the ability to target specific patients who may be most likely to benefit from this drug," Dr. Richard Pazdur, director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research, said in an agency news release.
The Merck & Co. drug was approved for use with a companion diagnostic test that is the first designed to detect PD-L1 expression in non-small cell lung tumors, the FDA said in the news release.
By blocking what is called the PD-1/PD-L1 pathway, Keytruda may help the immune system fight lung cancer cells. In 2014, the FDA approved Keytruda to treat patients with advanced melanoma following treatment with Yervoy (ipilimumab), another type of immunotherapy.
The Keytruda approval is based on clinical trials that showed tumors shrank in 41 percent of patients, and the effect lasted between two and nine months.
The most common side effects of Keytruda included fatigue, decreased appetite, shortness of breath or impaired breathing, and cough. The drug also has the potential to cause severe immune system-related side effects involving the lungs, colon, hormone-producing glands, nervous system, as well as rash and blood vessel inflammation, the FDA said.
Pregnant or breast-feeding women should not take the drug because it may harm the fetus or baby, the agency noted.
Earlier this year, the FDA approved the Bristol-Myers Squibb drug Opdivo (nivolumab) -- which also targets the PD-1/PD-L1 pathway -- to treat squamous non-small cell lung cancer.
"Our growing understanding of underlying molecular pathways and how our immune system interacts with cancer is leading to important advances in medicine," Pazdur said.
Lung cancer is the leading cause of cancer death in the United States, with about 221,000 new cases and 158,000 deaths in 2015, according to the U.S. National Cancer Institute. Non-small cell lung cancer is the most common type of lung cancer.