Pfizer's Lung Cancer Drug Receives Breakthrough Designation

The FDA has awarded Breakthrough Therapy status to Pfizer’s crizotinib (Xalkori) for ROS1-positive metastatic non-small cell lung cancer (NSCLC).

Xalkori is a kinase inhibitor currently approved in the United States for the treatment of NSCLC in patients whose tumors are anaplastic lymphoma kinase (ALK)-positive, as detected by an FDA-approved test. Now, Pfizer is seeking to expand the drug’s approved use to patients with ROS1-positive NSCLC, which occurs in about 1% of NSCLC cases.

The FDA granted Breakthrough Therapy designation to Xalkori for this potential indication after reviewing results from a global Phase 1 study demonstrating the drug’s anti-tumor activity in 50 patients with ROS1-positive advanced NSCLC.

“Xalkori pioneered precision medicine for ALK-positive metastatic NSCLC, and ROS1 represents a second molecular subgroup of NSCLC in which Xalkori has demonstrated a level of anti-tumor activity that can potentially make a real difference for patients,” said Mace Rothenberg, senior vice president of Clinical Development and Medical Affairs and chief medical officer for Pfizer Oncology, in a press release.

The most common adverse reactions to Xalkori include vision disorders, nausea, diarrhea, vomiting, and fatigue, while serious side effects observed in trials include pulmonary embolism, dyspnea, and pneumonia. In a phase 3 study of the drug, fatal adverse reactions occurred in 9 patients with previously treated ALK-positive metastatic NSCLC.