FDA Expands Approval of Pfizer’s Xalkori
FDA has given expanded approval to Pfizer’s Xalkori (crizotinib) to treat people with metastatic non-small cell lung cancer (NSCLC) whose tumors have an ROS-1 gene alteration. This gene alteration is present in about 1% 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” in 2011, an agency release says. Xalkori works by blocking the activity of the ROS-1 protein in tumors that have ROS-1 gene alterations, it says, adding that this effect “may prevent NSCLC from growing and spreading.”
Expanded approval was based on data from a study involving 50 patients with ROS-1 positive metastatic NSCLC. Patients received Xalkori twice daily to measure the drug’s effect on their lung cancer tumors. “Results showed 66% of participants experienced a complete or partial shrinkage of their NSCLC tumors, an effect that lasted a median of 18.3 months,” the agency says.