The US FDA has approved Xalkori (crizotinib) to treat people with advanced (metastatic) non-small cell lung cancer (NSCLC) whose tumors have an ROS-1 gene alteration, according to an agency announcement. Xalkori is the first and only FDA approved treatment for patients with ROS-1 positive NSCLC.

Lung cancer is the leading cause of cancer-related deaths in the United States, with an estimated 221,200 new diagnoses and 158,040 deaths in 2015, according to the National Cancer Institute.  ROS-1 gene alterations, thought to lead to abnormal cells, have been identified in various cancers, including NSCLC. ROS-1 gene alterations are present in approximately 1 percent of patients with NSCLC. The overall patient and disease characteristics of NSCLC with ROS-1 gene alterations appear similar to NSCLC with anaplastic lymphoma kinase (ALK) gene alterations, for which crizotinib use was previously approved. Xalkori was approved to treat certain patients with late-stage NSCLC that expresses an abnormal ALK gene in 2011.

“Lung cancer is difficult to treat, in part, because patients have different mutations, some of which are rare,” said Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “The expanded use of Xalkori will provide a valuable treatment option for patients with the rare and difficult to treat ROS-1 gene mutation by giving health care practitioners a more personalized way of targeting ROS-1 positive NSCLC.”

Xalkori is an oral medication that blocks the activity of the ROS-1 protein in tumors that have ROS-1 gene alterations. This effect on ROS-1 may prevent NSCLC from growing and spreading.