Pfizer's Xalkori was previously approved to treat NSCLC in patients whose tumors present with a different abnormal gene.
The latest approval will allow Xalkori to treat the roughly 1 percent of NSCLC patients who have an ROS-1 gene alteration, according to the FDA.
In a study of 50 patients, Xalkori was found to block the activity of the ROS-1 protein in tumors that possess an ROS-1 gene alteration, which may prevent NSCLC from spreading. Sixty-six percent of study patients had their tumors shrink while taking Xalkori.
NSCLC is a type of lung cancer. Lung cancer is a leading cause of cancer-related deaths in the US, the FDA reported.
Serious side effects of Xalkori include lung inflammation, liver problems, abnormal heart rhythm and vision loss. Patients also reported minor side effects.