Pfizer Inc. released full results from the phase 2 trial of lorlatinib in non-small cell lung cancer patients who were ALK or ROS1-positive.
The study, which included 275 patients, showed that 90% of ALK-positive patients, who had not received prior therapy, achieved an objective response rate — a measure of patients whose tumors shrank.
The objective response was 69% for those who were previously treated with crizotinib; 33% for those previously treated with a non-crizotinib ALK inhibitor; and 39% for those previously treated with two or three prior ALK inhibitors.
For ROS1-positive patients, the objective response was 36% regardless of prior treatment.
Lorlatinib is Pfizer's next-generation ALK inhibitor.
The company said it had come up with the drug after patients developed resistance to Xalkori, the first drug approved for the disease, and other ALK inhibitors.
In April, the U.S. Food and Drug Administration granted breakthrough therapy designation to lorlatinib.